BAB 6 Buku Standardisasi Spesifikasi Teknis Transformator Tenaga 30MVA (SK DIR NO.0632.K-DIR-2013)

BUKU STANDARDISASI SPESIFIKASI TEK NIS TRANSFORMATOR TENAGA PT PLN (Persero)

BUKU STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

PT PLN (PERSERO)

PT PLN (Persero) Lampiran I Keputusan Direksi PT PLN (Persero) Nomor : 0632.K/DIR/2013 Tanggal : 17 Oktober 2013

SAMBUTAN DIREK TUR UTAMA

Assalamualaikum Warahmatullahi Wabarakatuh Buku Standardisasi Spesifikasi Teknis Transformator Tenaga dan Penjelasannya ini merupakan himpunan spesifikasi teknis Transformator yang disusun dengan pertimbangan beragamnya spesifikasi Transformator tenaga di unit pembangunan dan pengelola penyaluran yang menyulitkan saat enjinering, pengadaan, konstruksi, operasi, pemeliharaan dan penyediaan material cadang. Dengan memperhatikan permasalahan di atas maka dirasa perlu untuk melakukan standardisasi spesifikasi transformator tenaga yang memperhatikan kualitas peralatan, kebutuhan sistem, keselamatan ketenagalistrikan, efisiensi, kemudahan konstruksi dan pemeliharaan penyaluran. Dengan terbitnya Buku Standardisasi Spesifikasi Teknis Transformator Tenaga ini maka spesifikasi teknis transformator tenaga yang dibuat oleh unit pengelola penyaluran dalam rangka pengadaan transformator tenaga harus mengacu pada standar ini. Pada kesempatan ini pula, disampaikan terima kasih yang sebesar-besarnya kepada seluruh anggota TIM Penyusun Buku Spesifikasi Transformator Tenaga PT PLN (Persero) yang telah bekerja keras dan meluangkan waktu, tenaga dan pikiran untuk menyelesaikan Buku Standardisasi Spesifikasi Transformator Tenaga ini. Semoga Allah SWT memberikan pahala dan berkah-Nya kepada seluruh anggota Tim. Wassalamualaikum Warahmatullahi Wabarakatuh

Direktur Utama

NUR P AMUDJ I

STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

1


TIM PENYUSUN BUKU STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

1.

Eko Yudo Pramono

NIP. 7094998 JA

2.

Djoko Mulyadi

NIP. 5886006 K3

3.

Jati Pharmadita

NIP. 8610306 Z

4.

Ratnasari Sjamsuddin

NIP. 6994025 P

5.

Nugraha Rohman

NIP. 6593070Z

6.

Sumaryadi

NIP. 6684317 K3

7.

Campy Hidayat

NIP. 6383022 LMK

8. 9.

Ahmad Muhaymin Ahmad Fauzan

NIP. 6294030 LMK NIP. 8510331 Z

10.

Tanjung Anggraini

NIP.8208459 Z

11.

M. Husen Hatala

NIP. 8109026Z

12.

Furqan ldris

NIP. 8408537 Z


2


DAFTAR ISI

SAMBUTAN DIREKTUR UTAMA ............................................................................................1 TIM PE NYUSUN ...................................................................................................................... 2 DAFTAR ISI ............................................................................................................................ 3 TECHNICAL PARTICULAR AND GUARANTEE ..................................................................... 5 1. TRANSFORMATOR DAYA 66/20 KV 30 MVA.............................................................. 5 2. TRANSFORMATOR DAYA 150/20 KV 30 MVA .......................................................... 17 3. TRANSFORMATOR DAYA 150/20/10 KV 60 MVA ..................................................... 29 4. INTER BUS TRANSFORMER 150/70/10 KV 60 MVA ................................................. 41 5. INTER BUS TRANSFORMER 150/70/10 KV 100 MVA ............................................... 53 6. INTER BUS TRANSFORMER 275/150/20 KV 83.3 MVA (KONVENSIONAL) ............. 65 7. INTER BUS TRANSFORMER 275/150/20 KV 83.3 MVA (AUTOTRANSFORMER) .... 79 8. INTER BUS TRANSFORMER 275/150/66 KV 167 MVA (AUTOTRANSFORMER) ..... 93 9. INTER BUS TRANSFORMER 500/150/71.5 KV 167 MVA (SINGLE PHASE) ........... 106 10. INTER BUS TRANSFORMER 500/150/71.5 KV 500 MVA (THREE PHASE) ............ 118 TECHNICAL SP ECIFICATIONS .......................................................................................... 130 1. GENERAL................................................................................................................ 130 1.1. WORK INCLUDED ................................................................................................... 130 1.2. QUALITY STANDARDS ........................................................................................... 130 1.2.1. GENERAL................................................................................................................ 130 1.2.2. STANDARDS ........................................................................................................... 130 1.2.3. CONFLICTS............................................................................................................. 131 1.3. SITE CONDITION .................................................................................................... 131 1.4. SERVICE CONDITION............................................................................................. 131 1.5. SUBMITTALS........................................................................................................... 131 1.5.1. LANGUAGE ............................................................................................................. 131 1.5.2. DOCUMENTS TO BE SUBMITTED.......................................................................... 131 1.6. 2. 2.1. 2.1.1. 2.1.2. 2.1.3. 2.1.4. 2.1.5. 2.1.6. 2.2. 2.2.1. 2.2.2. 2.2.3. 2.2.4.

TESTING INSPECTION ................................................................................... SPECIFICAND REQUIREMENTS ................................................................................... 132 132 TYPES AND MAIN PERFORMANCES ..................................................................... 132 FAULT CONDITIONS............................................................................................... 133 LOSSES .................................................................................................................. 134 VIBRATION AND NOISE.......................................................................................... 134 HARMONIC SUPPRESSION ................................................................................... 134 IMPEDANCE AND REGULATION ............................................................................ 135 TRANSFORMER GENERAL LAYOUT ..................................................................... 135 MAGNETIC CIRCUIT AND WINDINGS .................................................................... 137 MAGNETIC CIRCUIT ............................................................................................... 137 MAGNETIC POLARIZATION (FLUX DENSITY) ....................................................... 137 WINDINGS............................................................................................................... 137 INTERNAL EARTHING ARRANGEMENTS .............................................................. 138

2.3. 2.3.1. 2.3.2. 2.3.3. 2.3.4. 2.3.5. 2.3.6. 2.3.7.

TANKS ..................................................................................................................... 139 MAIN TANK ............................................................................................................. 139 CONSERVATOR TANK ........................................................................................... 141 PRESSURE RELIEF DEVICE .................................................................................. 141 OIL HANDLING FACILITIES .................................................................................... 141 JOINT FACES.......................................................................................................... 142 EARTHING TERMINALS.......................................................................................... 142 RATING PLATE ....................................................................................................... 142


3


2.4. 2.4.1. 2.4.2. 2.4.3. 2.4.4.

COOLING SYSTEM ................................................................................................. 143 GENERAL................................................................................................................ 143 RADIATORS/FORCED AIR COOLERS CONNECTED DIRECTLY TO TANK ........... 143 AIR BLOWERS ........................................................................................................ 143 COOLER CONTROL................................................................................................ 144

2.5. 2.5.1. 2.5.2. 2.5.3. 2.5.4. 2.5.5. 2.5.6. 2.5.7. 2.5.8. 2.6. 2.6.1. 2.6.2. 2.7. 2.8.

VOLTAGE CONTROL .............................................................................................. 144 GENERAL................................................................................................................ 144 ELECTRICAL REMOTE CONTROL ......................................................................... 145 INDICATION AND ALARMS..................................................................................... 146 AUTOMATIC VOLTAGE CONTROL......................................................................... 146 VOLTAGE REGULATION RELAY ............................................................................ 147 REMOTE CONTROL PANEL ................................................................................... 147 MARSHALLING BOX ............................................................................................... 148 CONTROL PRINCIPLE ............................................................................................ 149 PROTECTIVE DEVICES .......................................................................................... 149 TEMPERATURE INDICATING DEVICE ................................................................... 149 BUCHOLZ RELAY ................................................................................................... 150 DRYING OUT........................................................................................................... 150 BUSHING INSULATORS ......................................................................................... 150

2.9. CABLE TERMINATIONS.......................................................................................... 152 2.10. CABLES AND TERMINATIONS ............................................................................... 153 2.10.1. CABLE BOXES AND SEALING END CHAMBERS................................................... 153 2.10.2. DISCONNECTING CHAMBERS............................................................................... 153 2.10.3. TESTING ................................................................................................................. 153 2.10.4. SUPPLY OF CABLES .............................................................................................. 153 2.11. SPARE PARTS FOR S/S TRANSFORMERS ........................................................... 154 2.12. INSULATING OIL ..................................................................................................... 154 2.12.1. FILLING WITH OIL ................................................................................................... 154 2.12.2. SUPPLY OF TRANSFORMER OIL........................................................................... 154 2.13. PRE-APPROVED SUPPLIER LIST .......................................................................... 154 2.14. PREPARATION FOR TRANSPORT ......................................................................... 156 2.15. TESTS ..................................................................................................................... 156 2.16. SITE TESTS............................................................................................................. 163


4

LAMP IRAN I KE PUTUSAN DIREKS I PT P LN (PER SERO) Nomor : 0632.K/DIR/2013 Tanggal : 17 Oktober 2013

TECHNICAL P ARTICULAR AND GUARANTEE

Transformator Daya 150/20/10 kV 30 MVA


2.

TransformatorDaya 150/20 kV 30 MVA

TECHNICAL PARTICULAR AND GUARANTEE Transformator Daya 150/20/10 kV 30 MVA NO.

DESCRIPTION

UNIT

SPECIFIED

1

GENERAL

1.1

Standards

1.2

Factory

to be stated by bidder

1.3

Type and design number


1.4

Installation on site

1.5

Service conditions : a. Maximum altitude b. Temperature of ambient air and cooling medium c. Average monthly air temperature d. Average annual ambient temperature

1.6

IEC 60076 series, SPLN T3.002, SPLN 61 1997

Outdoor

meter

1000

°C

40

°C

30

°C

30

Installation environment a. Dust pollution rate b. Seismic disturbance

2

heavy or very heavy g

0,25

RATING AND PERFORMANCE

2.1

Number of phase per unit

3

2.2

Number of winding per phase

3

2.3

Purpose of tertiary winding

stabilizing

2.4

Vector group

YNyn0+d

2.5

Rated power (Sr) : a. For primary & secondary winding - Stage 1 (100% Sr) - Stage 2 (80% Sr) - Stage 3 (60% Sr) b. Tertiary winding - Stage 1 (100% Sr) - Stage 2 (80% Sr) - Stage 3 (60% Sr)

MVA

30

MVA MVA

N.A. 18

MVA

10

MVA MVA

N.A. 6


17


TECHNICAL PARTICULAR AND GUARANTEE Transformator Daya 150/20/10 kV 30 MVA NO. 2.6

2.7

2.8

2.9

DESCRIPTION

UNIT

SPECIFIED

Highest voltage (Um) for equipment : a. Primary winding

kV

170

b. Secondary winding

kV

24

c. Tertiary winding

kV

12

Rated voltage (Ur) : a. Primary winding

kV

150


kV

22

c. Tertiary winding

kV

10

point: a. Primary winding

kV

17,5


kV

24

Highest voltage (Um) for neutral

Tapping of primary winding (minimum) : a. Number of steps

16

b. Number of taps

17 (-8 to +8)

c. Numbering of tap positions

2.10

2.11

2.12

1 to 17

d. Tapping factor (Ud/Ur)

%

1,25

Short-circuit impedance (at 75 °C, rated power) a. At principal tap

%

12,5

b. At maximum tap

%


c. At minimum tap

%


% % %

to be stated by bidder to be stated by bidder to be stated by bidder

% % %


% % %


Voltage drop (or rise) as % of rated voltage at full load, At power factor 1 & 75 °C : a. At principal tap b. At maximum tap c. At minimum tap At power factor 0.8 & 75 °C : a. At principal tap b. At maximum tap c. At minimum tap Percent reactance drop at full load, power factor 1tap & 75 °C a. At principal b. At maximum tap c. At minimum tap


18



DESCRIPTION

UNIT

SPECIFIED

2.13

Percent resistance drop at full load, power factor 1 & 75 °C a. At principal tap b. At maximum tap c. At minimum tap

% % %


Rated current : a. Primary winding

A

115,5


A

787,3 (at 22kV)

c. Tertiary winding

A

333,3 (phase current)

a. Primary winding b. Secondary winding

kV kV

650 125

c. Tertiary winding

kV

75

Switching impulse withstand voltage: a. Primary winding

kV

N.A.


kV

N.A.

c. Tertiary winding

kV

N.A.

Power frequency withstand voltage: a. Primary winding

kV

275

2.14

2.15

2.16

2.17

2.18

2.19

2.20

Lightning impulse withstand voltage:


kV

50

c. Tertiary winding

kV

28

Symmetrical short-circuit withstand current (2 seconds) : a. Primary terminals

kA

40

b. Secondary terminals

kA

25

c. Tertiary terminals

kA

N.A.

Minimum efficiency (at 75 °C, 50 Hz, continuous rated power, at principal tap) : a. power factor 1

%

99,75

b. power factor 0.8

%

99,65

Highest efficiency and its load point - Stage 1 (100% Sr)

%

(> point 2.19.a) at . . . . %

% %

(> point 2.19.a) at . . . . % (> point 2.19.a) at . . . . %

- Stage 2 (80% Sr) - Stage 3 (60% Sr)


19



2.22

DESCRIPTION

UNIT

SPECIFIED

Maximum no-load current at principal tap : a. For rated voltage

% In

0,2

b. For 105 % of rated voltage

% In


c. For 110 % of rated voltage

% In


Maximum no-load loss at 50 Hz,

kW

18

a. At principal tap, excluding fan loss b. At minimum tap

kW kW

65 to be stated by bidder

c. At maximum tap

kW


d. Power for cooling fans

kW

2

e. Power for cooling pumps

kW

N.A.

at rated voltage & principal tap 2.23

Maximum load loss at continuous rated power (75 °C, 50Hz, power factor 1) :

2.24

Hot spot factor

2.25

Maximum temperature rise (refer to point 1.5 d) a. Average winding

K

55

b. Top oil

K

50

c. Hot spot

K

68

Maximum winding hot spot temperature (refer to point 1.5 d) a. Long Emergency overload

°C

120

b. Continous loading

°C

98

dB

71

dB

N.A.

dB

67

mm

Grain Oriented Hi-B silicon steel, Laser or Non Laser steel AK Steel / POSCO Steel / Nippon Steel / ThyssenKrupp Steel/ JFE 0.23 / 0.27

2.26

2.27

3 3.1

Sound pressure level at 100% rated voltage: - Stage 1 (100% Sr), measuring distance 2 m - Stage 2 (80% Sr), measuring distance 2 m - Stage 3 (60% Sr), measuring distance 0,3 m

1,3

CORE Core Materials (IEC 60404) a. Steel Sheet material b. Name of factory of sheet steel c. Thickness


20



DESCRIPTION

UNIT

SPECIFIED

Tesla

1,85

Watt/kg

max 0.95

3.2

Minimum Magnetic polarization for H = 800 A/m

3.3

Maximum specific core loss at 1.7 Tesla, 50 Hz

3.4

Maximum flux density a. Continuous rated power

Tesla

1,7

b. Worst emergency condition

Tesla

1,88

ton


3.5

4 4.1

Minimum weight of core

WINDINGS Conductor a. Conductor material b. Conductor manufacturer - Primary winding

ASTA / Metrod / Essex / Shenyang

- Tertiary winding


- Secondary winding

disc / helical disc / helical multi layer / layer / disc / helical

e. Winding insulation - Primary winding - Secondary winding - Tertiary winding


Insulation paper a. Insulation material c. Class of insulation d. Minimum degree of polimerization after Oven process

4.4


- Tertiary winding

b. Insulation paper manufacturer

4.3


- Secondary winding c. Minimum total conductor weight including insulation d. Winding configuration - Primary winding

4.2

high purity copper

Uniform/graded design of winding insulation : a. Primary winding

thermally upgraded paper Weidmann / Munksjö / Pucaro (Class A) 900

` graded


uniform

c. Tertiary winding

uniform

Winding Arrangement



21


TECHNICAL PARTICULAR AND GUARANTEE Transformator Daya 150/20/10 kV 30 MVA NO. 4,5

4,6

4,7

5

DESCRIPTION Maximum current density : a. Primary winding

UNIT

SPECIFIED

A/mm²

2,5


A/mm²

2,5

c. Tertiary winding

A/mm²

3,25

Phase connections : a. Primary winding

star


star

c. Tertiary winding

delta

Connection of OLTC

primary windings at the neutral side

ON LOAD TAP CHANGER

5.1

Design

5.2

Type

5.3

Construction : a. selector switch

yes

b. diverter switch & tap selector

yes

c. change over selector

yes

Driving mechanism : a. manual operation below cover

yes

b. motor drive

yes

c. with o/c circuit breaking

yes

5.4

5.5

Motor drive unit type

5.6

Completed with transducer for tap position indicator

6

in-tank mounted MR Vacutap (Germany)

MR ED 100 yes

OIL

6.1

Main tank and on load tap changer oil type

6.2

Oil manufacturer

Nynas Libra / Shell S2 - ZU I / Total Isovoltine II

6.3

Corrosive sulphur

Non-corrosive (IEC 60296)

6.4

Oil preservation system a. Rubber bag manufacturer b. Dehydrated breather manufacturer

-

-

Uninhibited Certified Nepthanic Base

Rubber Bag + Maintenance free dehydrating breather Pronal / Fujikara / Musthane MR - MTraB / Comem


22



DESCRIPTION

6.5

Volume of Oil (min)

7

TERMINATIONS

7.1

UNIT

SPECIFIED

kl


Termination for phases : a. Primary b. Secondary

oil to air or oil to SF6 or oil to oil bushing oil to air bushing

c. Tertiary 7.2

7.3

oil to air bushing

a. Termination for primary and secondary neutrals b. Terminations for one corner of delta tertiary winding

bushings bushings

Primary and Secondary bushings

Primary

Secondary

a. Name of Manufacturer & Type

HSP / ABB - Micafil / ABB / Alstom

NGK / HSP / Knobel / Comem / Cedaspe / Alstom Porcelain

b. Insulator

Porcelain

c. Type of insulation d. Internal conductor : - Type - Cross section

mm²

- Outer terminal - Material of outer terminal - Connection details

to be stated by bidder to be stated by bidder to be stated by bidder Cylindrical stud

Copper

Copper

Draw Rod Yes Copper

Copper

kV

170

24

A min.

1250

2500

kA

40

- Material of bottom contact

g. Rated short-time current (2 seconds) h. Dry impulse withstand voltage

non-condenser

to be stated by bidder Yes

- Bottom contact e. Highest voltage(Um, r.m.s. values) f. Rated current

Resin Impregnated Paper to be stated by bidder to be stated by bidder to be stated by bidder Cylindrical stud

≥

16

kV

750

145

i. Switching impulse withstand voltage j. Power-frequency test voltage

kV

N.A.

N.A.

1 min wet (r.m.s. values) k. Maximum dielectric dissipation factor (tan delta) at power frequency l. Completed with test tap

kV %

325 0.5

50 N.A.

yes

N.A.


23



7.5

7.6

DESCRIPTION

UNIT

Dimension

Primary

Secondary

a. CT Space / facility (L4)

300

b. Flange to bottom end nut (L1)

720

c. Flange Diameter (D3)

335

d. Hole to Hole diameter (D2)

290

to be stated by bidder to be stated by bidder to be stated by bidder to be stated by bidder

Bushing current transformer a. Core 1

Primary N.A.

Secondary N.A.

b. Core 2

N.A.

N.A.

c. Core 3

N.A.

N.A.

d. Core 4

N.A.

N.A.

Tertiary 1

Tertiary 2

NGK / HSP / Knobel / Comem / Cedaspe


b. Insulator c. Type of insulation

Porcelain non-condenser

Porcelain non-condenser

d. Internal conductor :



Tertiary bushings a. Name of Manufacturer & Type

- Type - Cross section

mm²

- Outer terminal - Material of outer terminal

Copper

Copper



Copper

Copper

kV

12

12

A min.

1600

1600

- Connection details - Bottom contact - Material of bottom contact e. Highest voltage(Um, r.m.s. values) f. Rated current g. Rated short-time current (2 seconds) h. Dry impulse withstand voltage i. Switching impulse withstand voltage j. Power-frequency test voltage 1 min wet (r.m.s. values) k. Dielectric dissipation factor (tan delta) 7.7

SPECIFIED

kA

16

≥

16

kV

75

75

kV

N.A.

N.A.

kV

28

28

%

N.A.

N.A.

Neutral bushings : - Manufacturer and type - Highest voltage

≥

kV

Primary

Secondary



52

24


24



DESCRIPTION

UNIT

SPECIFIED

8

COOLING SYSTEM :

8.1

Cooling method a. Stage 1 (100% Sr)

ONAF

b. Stage 2 (80% Sr) c. Stage 3 (60% Sr)

N.A. ONAN

8.2

Radiator mounted on tank

8.3

Radiator height

8.4

Number of group of radiator

8.5

Number of radiator per group

8.6

Radiator and tube bundle rust protection

8.7

Number of group of cooling fan

8.8

Number of cooling fan per group

8.9

Cooling fan motor : a. Nominal voltage (1ph. / 3 ph.)

V

230 / 400

b. Nominal power of each motor

kVA


8.10

Life of cooling fan (operating hour)

hour


8.11

Number of cooling pump

8.12

yes Higher than main tank with swan neck type to be stated by bidder pcs

hot dip galvanized and painting

to be stated by bidder pcs

9.1

Cooling pump motor :

N.A.

a. Nominal voltage (1ph. / 3 ph.)

V

b. Nominal power of each motor

kVA

N.A. N.A. N.A.

MAIN TANK AND CONSERVATOR Main tank materials : a. Name of factory


b. Design c. Grade of steel

cover type to be stated by bidder

d. Thickness (top /wall/base) 9.2


N.A.

c. Operation hour counter

9


mm


The minimum withstand-pressureof main tank : a. Positive internal pressure

kg/mm²

normal pressure + 35 kPa

b. Vacuum

kg/mm²

Full vacuum


25



9.3

DESCRIPTION

UNIT

Conservator tank design : (main & oltc oil separated) a. Name of factory


b. cylindrical/box-type

cylindrical

c. Grade of steel d. Thickness (top/wall/base)

to be stated by bidder mm

e. Oil level indicator type 9.4

SPECIFIED

to be stated by bidder visual window and magnetic type

Conservator tank mounting : a. attached above main tank

yes

b. For delivery : separated

yes

9.5

Air-sealed conservator with dehydrated breather (Rubber Bag)

yes

9.6

Type & number of construction of oil drain assembly (for oil sampling, online DGA, filtering, vaccuum)


9.7

Type and number of construction of slide valves


9.8

Type of sealings and gaskets : a. asbestos fibre


b. oil-proof rubber 9.9

yes

Tank rust protection : a. rust-proofing

yes

b. marine coated painting

yes

c. name & type of paint


d. colour 9.10

10

RAL 7032

Bottom base design

skid

CONTROL AND INDICATION

10.1

Marshalling box degree of protection

IP 55

10.2

Control and Indication

10.3

DC Supply for control and indication

Vdc

110

10.4

Supply voltage for motor of on load tap changer, fan, and pump

Vac

230 / 400

local & remote ; manual & electrical


26



10.5

10.6

DESCRIPTION

UNIT

Temperature monitor a. Oil temperature

OTI

b. Winding temperature

WTI

c. Hot spot temperature

fiber optic for type test unit only

Fiber optic temperature sensor a. Sensor manufacturer

Neoptix / Luxtron

b. Sensor type / designation


c. Completed with temperature monitor b. Number of sensors

11 11.1

SPECIFIED

yes 3 at each HV, LV, and TV windings (9 total)

PROTECTION Buchholz relay : a. manufacturer & Type

EMB / COMEM / Qualitrol

b. waterprof contacts and microswitches c. Maintenance Valves at both sides

yes Required

d. Protection functions

gas accumulation, insulation liquid loss insulation liquid flow surge

e. Gas collector for buchholz relay 11.2

yes

Overpressure relay for on load tap changer : a. manufacturer & Type b. waterprof contacts and microswitches c. maintenance valves at both sides

MESSKO / Qualitrol yes

11.3

Provision for fire prevention system

yes

11.4

Pressure Relief Device a. Type

MESSKO / Qualitrol

b. Completed with cover

yes

Ingress protection rating of relays and terminals box

IP66

11.5

12

yes

WEIGHT AND DIMENSION

12.1

Weight of tank and fitting

ton


12.2

Weight of active part

ton


12.3

Maximum total weight

ton

120


27



DESCRIPTION

UNIT

SPECIFIED

12.4

Height of the top point

m


12.5

Total length

m


12.6

Total width

m


12.7

Maximum height of lifting during assembly or maintenance

m


12.8

Largest package : - Weight - Dimensions (H x L x W)

ton mxmx

to be stated by bidder to be stated by bidder

m 12.9

Heaviest package : - Weight - Dimensions (H x L x W)

ton mxmx m

to be stated by bidder to be stated by bidder


28

LAMP IRAN I KE PUTUSAN DIREKS I PT P LN (PER SERO) Nomor : 0632.K/DIR/2013 Tanggal : 17 Oktober 2013

TECHNICAL SPECIFICATION


TECHNICAL SPECIFICATIONS

POWER TRANSFORMER 1. 1.1.

GENERAL WORK INCLUDED The Work includes design, manufacturing, tests and inspection, packing and shipping, foundation guide design, guarantee as specified of substation power transformers including accessories, and the followings if specified: custom clearance, inland transportation, site assembly and site test.

1.2. 1.2.1.

QUALITY STANDARDS GENERAL Equipment/materials testing, cleaning, services and reports to meet the general and specific requirements including technical particulars and drawings (if any) of this specification, specified standards, codes and other applicable standards.

1.2.2.

STANDARDS In summary the equipment/materials shall conform to the latest applicable standards of sponsor organizations not limited to the followings: SNI : Standard Nasional Indonesia SPLN : Standar Perusahaan Listrik Negara SPLN 8 (Series) : TransformatorTenaga SPLN 61 : SpesifikasiTransformatorTenagaTeganganTinggi SPLN T3.002 : TeganganPengenalTransformatorTenaga Dan JangkauanPenyadapanPengubahSadapanBerbebanPada System 66 kV, 150 kV, 275 kV, dan 500 kV Unless specified otherwise or modified herein, all IEC standards (e.g. with the following series numbers) are directly or indirectly applicable, including parts and addenda: 60060 60076 (Series) 60137 60214 (Series) 60270 60296 (Series) 60404 (Series) 60567

: : : : : : : :

60599

:

60616 60529 61033

: : :

High voltage test techniques Power transformers Insulating bushings for alternating voltages above 1000V On-load tap-changers Partial discharge measurements Specification for insulating oils Magnetic materials Oil-filled electrical equipment – Sampling of gasses and of oil for analysis of free and dissolved gases – Guidance. Mineral oil-impregnated electrical equipment in service Guide to the interpretation of dissolved and free gases analysis Terminal and tapping markings for power transformers Degrees of protection by enclosures (IP Code) Test methods for the determination of bond strength of impregnating agents to an enameled wire substrate.


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1.2.3.

CONFLICTS a. If conflicting requirements among applicable standards exist, the most stringent one shall govern. b. specification If this specification conflicts in any applicable standard(s), this shall take precedence andway shallwith govern.

1.3.

SITE CONDITION The equipment shall be suitable for operation under site service condition as specified in Technical Particulars and Guarantees (TPG).

1.4.

SERVICE CONDITION The equipment will be installed outdoor and will be subject to the minimum and maximum environmental conditions asspecified in Technical Particulars and Guarantees (TPG). The equipment shall be suitable for operation under the ambient conditions specific to their respective location while in service.

1.5.

SUBMITTALS

1.5.1.

LANGUAGE All documents are to be written inBahasa Indonesia and/or English

1.5.2.

DOCUMENTS TO BE SUBMITTED The following data shall be submitted: When Bidding a. Preliminary outline drawings showing dimensions and arrangement/

b. c. d. e. f. g. h.

position of major external features including conservator, terminals, cooling equipment and other essential appurtenances. These drawings shall show parts and masses to be removed for transportation. Technical particulars and guarantee Type test certificate for each type of transformers and accessories for the same rating (Voltage and Capacity) or higher Technical literature on the equipment Satisfactory Operation Statement Letter from users Certificate of ISO-9001 (Latest Version) Quality Manual for Review & Acceptance Other data if requested during evaluation.

After the Award of the Contract a. Foundation guide drawings b. or Outline and detail as requested fordrawings approval referring to appropriate engineering practices c. Calculation note: - Losses - Temperature Rise - Short Circuit - Impulse withstand d. Copy of raw material Certificate of Origin e. QA/QC Report STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

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f.

Method of Inspection and Testing - Type Test and Routine Test Procedure - Factory Acceptance Test Procedure - Site Acceptance Test Procedure g. Test report (Type Test and Routine Test) in hard copy and soft copy before h. delivery Transportation procedure and acceptance criteria i. As built drawings in hard copy and soft copy j. Operating and maintenance instructions in hard copy and soft copy.

1.6.

TESTING AND INSPECTION The equipment is subject to inspection and test by the Purchaser/Engineers during the course and on completion of manufacture to ensure compliance with this specification and to provide the necessary data. The Bidder may submit type test certificate of test which has been carried out on identical equipment. Not withstand any provision in standard the Purchaser/Engineers shall have the right to reject such certificate in lieu of the specified test. During the manufacturing process, Purchaser has the right to audit the transformer manufacturer and component suppliers according to Quality Assurance / Quality Control procedure of PLN, on Purchaser’s expense if necessary. Audit result can be used by the Purchaser to accept or reject the transformers. Factory Acceptance Test (FAT)shall be carried out by the Manufacturer and will be witnessed by the Purchaser or Purchaser Engineers. The Manufacturer shall prepare all completed transformers (including accessories) of each batch ready for routine test to be witnessed by Purchaser or Purchaser Engineers. All costs or expenses in all cases of Factory Acceptance Test shall be borne by the Bidder. The Bidder shall guarantee that the Manufacturer will provide all things necessary for the carrying out the required tests including electric power, instruments, temporary connections, etc. All instruments used in tests shall carry calibration certificates from an accredited testing laboratory and shall perform within the limits of error necessary to carry out the tests satisfactorily. The instruments are subject to the approval of the Purchaser Engineer. The Bidder shall supply to the Purchaser, as soon as practicable after tests, necessary copies of the relevant test certificates which shall contain details of each test performed, records, results and calculations shall also be provided. If any item fails to comply with the requirements for a test, the Purchaser may reject the item or defective component thereof whichever he considers necessary and after replacement, adjustment or modification as directed by the Purchaser, the Bidder shall repeat the tests as necessary to demonstrate compliance with the specification at his extra cost.

2. 2.1.

SPE CIFIC REQUIREMENTS TYP ES AND MAIN PERFORMANCES The transformers shall be core type, oil immersed, suitable for outdoor installation and capable for continuous operation without injurious heating when delivering


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winding currents at nominal and highest/rated voltages of 3 phase 50 Hz power system. The transformers shall comply with the quality standards specified (clause 1.2) and their current carrying capacity shall be limited only by the capacity of the core and coils, not by other current carrying components such as on-load tap changer or bushings. The voltages between phases on the higher and lower voltage windings measured at no load shall be those corresponding to the normal ratios of transformation. On load tap changer shall be provided at the primary side for varying the ratio of transformation using tapping as stipulated on the technical particular and guarantee. The transformer shall have capacity and other ratings as specified at the ambient temperature 30°C and shall comply with IEC 60076-2 as regards the corrected temperature rise (maximum 55°C for windings and 50 °C for oil) and IEC 60076-7 for over loads on all tapping irrespective of power flow direction and with secondary voltage winding at the specified nominal voltage. Each transformer shall be fitted with tank mounted coolers capable of dissipating the at continuous maximum spotlosses temperature exceeding 98°C. rating (CMR) without the measured winding hot In more detail, the requirements are listed in the Technical Particulars and drawings (if any).

2.1.1.

FAULT CONDITIONS It is to be assumed that the amount of generating plant simultaneously connected is such that normal voltage will be maintained on one side of any transformer when there is a short circuit between phases or any phase to earth on the other side. The winding shall be capable of withstanding the forces to which it is subjected under all conditions, particularly the forces due to a short circuit between terminals or between any terminal and earth, with full voltage maintained on all other windings intended for connection to external sources of supply and allowing for any feed back through windings connected to rotating machines. Evidence shall be submitted with the proposal to prove with calculations according to IEC 60076-5 the ability of each type of transformer to withstand, on any tapping, fault conditions as described below: •

Thermal ability to withstand short-circuit Average temperature of each windings shall not exceed 200⁰C with the duration of symmetrical short-circuit current to be used for calculation of the thermal ability to withstand short circuit shall be 4 seconds.

•

Dynamic effects of short circuit Theoretical evaluation of the ability to withstand dynamic effects of short circuit shall result force or stress figures which are 30 % less than values stipulated in

A ofshall IECinclude 60076-5:2006. TheAnnex proposal a brief description of those transformers or parts thereof which have been subjected to short circuit tests or for which short circuit calculations are available. It is preferred that this information relates to designs comparable with the transformers offered but in the event this is not so the Purchaser reserves the right to require calculations to prove that the design of transformers offered will satisfactorily comply with this Clause; such calculations being in accordance with


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IEC 60076-5.

2.1.2.

LOSSES The Bidder shall complete the Technical Particulars form, values for components of losses comprisingnoload loss, load loss at continuous maximum rating (C.M.R.) and auxiliary loss if any. The total losses shall be as low as is consistent with transport restrictions, reliability and economic use of materials. The Bidder shall state the maximum losses including tolerance. If the losses measured on test exceed the guaranteed values, then the Contract Price for the transformer shall be reduced in proportion to the amount by which the losses measured on tests exceed the guaranteed losses. The cost of losses: No-load loss at Rupiah per kW

Rp86.063.698,-

Load lossat Rupiah per kW

Rp55.080.766,-

Cooling fanat Rupiah per kW

Rp21.515.924,-

Any transformer shall be rejected after Factory Acceptance Test (FAT) if the losses exceed the guaranteed value by an amount in the following: Total Losses

10%

Component Losses 15% (unless the total loss exceed 10%)

2.1.3.

VIBRATION AND NOISE The transformers shall be so designed and constructed that harmful vibration is eliminated and that no avoidance noise will occur at any operating conditions. The level of vibration shall not adversely affect any clamping or produce excessive stress in any material and the noise must be as low as possible. Measurement of noise level of any transformer and auxiliaries shall be in accordance with the IEC 60076-10whichever the lowest and the measured values shall not exceed the figures specified in the Technical Particulars. Noise level tests to be carried out on all transformers.

2.1.4.

HARMONIC SUPPRESSION Transformers shall be designed with particular attention to the suppression of harmonic voltages, especially the third, fifth,and seventhharmonics and to minimize the detrimental effects or interference with communication circuit resulting therefore. Tertiary Winding (for 150/20 kV and 150/66 kV transformers): The tertiary or stabilizing winding is required for the purpose of suppressing harmonics. To avoid2the effect of(for over-voltage, one corner of on thisthe winding to will be brought out through bushings test and measurement) tank is and be directly grounded. Due to the shifting of one corner to earth point, the insulation of tertiary windings to all part including to tapping winding shall be designed adequately.


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2.1.5.

IMPEDANCE AND REGULATION The Bidder shall state in the Schedule of Technical Particulars and Guarantee the values of impedance measured on principal and extreme tapping and the voltage regulation from no load to C.M.R. at unity power factor and at 0.8 lagging power

2.1.6.

factor with constant voltage across the higher voltage windings. TRANSFORMER GENERAL LAYOUT Transformers shall be designed with general layout as following: 1. 2. 3. 4. 5. 6. 7. 8.

HV Bushing HVN Bushing LV Bushing LVN Bushing TV Bushing Marshalling Kiosk Conservator Tap Changer

9. Tap Changer Motor Drive Unit 10. Radiator 11. Fire Protection 12. Base Plate

3 phase transformer


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1 phase transformer

1 phase autotransformer


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2.2.

MAGNETIC CIRCUIT AND WINDINGS

2.2.1.

MAGNETIC CIRCUIT The design of the magnetic circuit shall be such as to avoid static discharges, development of short circuit paths internally earthen structure, and the production of flux components normalortoto thethe plane of theclamping laminations. Each lamination shall be insulated with a material stable under the action of pressure and hot oil. The winding structure and major insulation shall be designed to permit an unobstructed flow of cooling oil through core cooling oil ducts to ensure efficient core cooling. The magnetic circuit shall be insulated from all structural parts, and shall be capable of withstanding a test voltage to core bolts and to the frame of 2500 volts rms for one minute.

2.2.2.

MAGNETIC POLARIZATION (FLUX DENSITY) Core shall be sheets constructed of non-aging, high permeability cold minimum rolled grainmagnetic oriented silicon steel of the Hi-B or higher grade having polarization value of 1.85 Tesla at 800 A/m and maximum specific total loss 0.95 1 Watt/kg at 1.7 Tesla and 50 Hz. Adequate evidence for the supply from the steel sheets manufacturer shall be provided before/during inspection/tests. The steel sheets shall be properly annealed after cutting to suitable sizes and rolled to insure smooth surfaces at the edges. Both sides of each sheet shall be carlite-coated and insulated with heat resisting varnish to minimize eddy current losses. The cores shall be carefully assembled and rigidly, strongly enough clamped to insure adequate mechanical strength to support the windings and to prevent shifting/displacement of laminations during shipment, transportation, operation, short circuit or other stresses and also to reduce vibration/noise to a minimum under operating conditions. The clamping frames must be insulated against the sheets.

2.2.3.

WINDINGS The transformer windings shall be constructed from high conductivity copper and assembled in a manner as best suited for the particular application. The application of ZnO is not allowed in any part of the windings. Proper consideration shall be given to all factors of service such as high dielectric and mechanical strength of insulation, coil characteristics and minimum restrictions to the free circulation of oil. Coil shall be made up, shaped and braced to provide for expansion and contraction due to temperature changes in order to avoid abrasion of insulation and to provide rigidity to resist movement and distortion caused by abnormal operating conditions, and shock during shipment and transportation. Adequate barriers shall be provided between windings and core and between high voltage and low voltage windings. End coils shall have additional protection against abnormal line disturbances. The entire design, construction and treatment of the windings and their assembly on the core shall embody the latest improvements. Stabilization treatment for winding stacks shall be made to manufacture windings


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which are made mechanically stable and solid. The assembled core and coils shall be dried under a vacuum condition, immediately impregnated, and immersed in dry oil. The 150 kV star connected windings shall have thermally upgraded paperaccording to IEC-60076-7. Thermally upgraded paper is cellulose-based paper which has been chemically modified to reduce the rate at which the paper decomposes. Ageing effects are reduced either by partial elimination of water forming agents (as in cyanoethylation) or by inhibiting the formation of water through the use of stabilizing agents (as in amine addition, dicyandiamide). A paper is considered as thermally upgraded if it meets the life criteria defined in ANSI/IEEE C57.100; 50 % retention in tensile strength after 65 000 hours in a sealed tube at 110 °C or any other time/temperature combination given by the equation (see IEC 60076-7). All transformer windings below 150 kV shall have uniform insulation as defined in IEC-60076-7. The neutral terminal shall be permanently connected to earth, directly or through a current transformer, but without any intentionally added impedance in the connection. The separate source AC withstand voltage shall be at least 38 kV for one minute. The insulation shall be provided against attack by mouldsand other tropical effect and shall be tropicalized according with the related standards. The transformers shall be designed to withstand the impulse voltage levels and the power frequency voltage tests specified in the Schedule of Technical Particulars. The windings shall be located in a manner which will ensure that they remain electrostatically balanced and that their magnetic centers remain coincident under all conditions of operation. The windings shall also be thoroughly seasoned during manufacture by the application of axial pressure at a high temperature for such length of time as will ensure that further shrinkage is unlikely to occur in service. All electrical connections within windings shall be brazed to withstand the shocks which may occur through rough handling and vibration during transport, switching and other transient service conditions. Coil clamping rings shall be of non magnetic steel or insulating material built up from flat laminations. Axially laminated material other than bakelised paper is not to be used. Where bakelised paper rings are used with the layers of paper lying in the axial direction, the rings may be relied upon to provide the major insulation between the windings and frame, subject to there being adequate creepage distance. Any metal pieces in contact with laminated rings shall be designed and secured so that they do not weaken the electrical or the mechanical properties of the rings. If the winding is built up of sections or of disc coils separated by spacers, the clamping arrangements shall ensure that equal pressures are applied to all columns of spacers.

2.2.4.

INTERNAL EARTHING ARRANGEMENTS All metal parts of the transformer, with the exception of the individual core lamination, core bolts, and associated individual clamping plates, shall be maintained at some fixed potential.


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The top main core clamping structure shall be connected to the tank body by a copper strap and the bottom main core clamping structure shall be earthen by one or more of the following methods: (a)

by connection through vertical tie rods to the top structure.

(b)

by direct metal-to-metal contact with the tank base maintained by the weight of the core and windings.

(c)

by connection to the top structure on the same side of the core as the main earth connection to the tank.

The magnetic circuit shall be earthen to the clamping structure at one point through a removable link placed in an accessible position just beneath an inspection opening in the tank cover and which, by disconnection, will enable the insulation between the core and clamping plates, etc. to be tested at voltages up to 2.5 kV for the purpose of checking deterioration during service. The connection to the link shall be on the same side of the core as the main earth connection. These requirements are compulsory. Magnetic circuits having an insulated sectional construction shall be provided with a separate link for each individual section and the arrangement of the connections shall be subject to the approval of the Purchaser/Engineer. Where oil ducts or insulated barriers parallel to the plane of the laminations divide the magnetic circuits into two or more electrically separate parts, the ducts and insulating barriers which have the thickness greater than 0.25 mm are to be bridged with tinned copper strips so inserted as to maintain electrical continuity. Where coil clamping rings are of metal at earth potential, each ring shall be connected to the adjacent core clamping structure on the same side of the transformer as the main earth connection. Main earthing connections shall have a cross-sectional area of not less than 80 sqmm but connections inserted between laminations may have cross-sectional areas reduced to 20 sqmm when in close thermal contact with the core.

2.3. 2.3.1.

TANKS MAIN TANK Each transformer shall be enclosed in a suitably stiffened welded steel tank such that the transformer can be lifted and transported without permanent deformation or oil leakage. The construction shall employ weldable structural steel. Lifting lugs shall be provided suitable for the weight of the transformer including core and windings, fittings, and with the tank filled with oil. Each tank shall be provided with at least four jacking lugs, and with lugs suitably positioned for transport on a beam transporter. They must be rated for the most unfavourable load distribution on two diagonals. The base of the tank shall be so designed that it is possible to move the complete transformer unit in any direction without injury when using rollers, plates or rails. Transformers shall have skid bases. Detachable under-bases must not be used. If wheelbases are requested, the device for fastening the rollers on the rails is part of delivery. The rails shall also be supplied of the quality at least St 37 and finished with hot dip galvanization. All joints, other than those which may have to be broken shall be welded. Defective welded joints may be re-welded subject to the written approval of the Purchaser/Engineer. The transformer shall be provided with a suitable steel tank of substantial


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construction which will be oil-tight and gas-tight. For bell type design of the tank, the bottom joint between the tank and base shall be provided with suitable flanges and gaskets having sufficient and properly spaced bolts so that the assembly will be oil-tight and gas-tight. All gaskets shall be made of high quality material, which will not deteriorate under tropical and site service conditions specified. The tank shall have sufficient strength, not distort when lifted and to withstand an internal pressure and also external pressure under a vacuum without damage or permanent deformation. The transformer tank shall be capable of withstanding without deflection exceeding the values stated in clause 2.15. vacuum of 508 mm of mercury less than atmospheric pressure when empty of oil, or the vacuum required by the recommended drying-out procedure, whichever is the greater. The tank and cover shall be designed in such a manner as to leave no external pockets in which water can lodge, no internal pocketsin which oil can remain when draining the tank or in which air can be trapped when filling the tank, and to provide easy access to all external surfaces for painting. The interior surface of the tanks shall be painted with an oil resistant coat, the exterior surface with a primer and two finish coats. Each radiator bank shall be connected to the main tank through flanged valves mounted on the tank at top and bottom, and each bank shall be fitted with drain valve and air release plug. Inspection openings shall be provided to give access to the internal connections of bushings, winding connections and earthing links. Each opening shall be currently located and must be of ample size for the purpose for which it is intended. All inspection covers shall be provided with lifting handles. It must be possible to remove any bushing without removing the tank cover. Pockets shall be provided for a stem type thermometer and for the bulbs of temperature indicators. These pockets shall be located in the position of maximum oil temperature and it must be possible to remove any bulb without lowering the oil level in the tank. Captive screwed caps shall be provided to prevent the ingress of water to the thermometer pockets when they are not in use. Whether accommodation shall be provided for bushing current transformers or for outdoor weatherproof neutral current transformers for primary/secondary side of each type are specified in the Technical Particulars. The transformer shall be provided with globe-type or butterfly-type valves as required for: - Drain valve - Oil sampling incl. facilities - Lower filter press connection. - Upper filter press connection - Isolating each radiator (in-let) - Isolating each radiator (out-let) -Isolating the both sides of bucholz - Isolating the both sides of OLTC relays - Filter press connection for compartment of diverter switch of OLTC. All oil valves shall be specially designed for use with insulating oil and will hold hot


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oil without leaking. The transformer shall be provided with pressure release device(s), a ladder for inspection with anti-climbing plate, cable conduits for wiring of relay and current transformer circuits, and rod type thermometer shall be mounted in a well so that it can be changed without lowering oil in the tank. To facilitate installation, center marks, level marks and center of gravity marks shall be provided at suitable portions of the tanks or bases. The Contract shall include the design of transformer foundation pads.

2.3.2.

CONSERVATOR TANK Each transformer shall be provided with an overhead conservator tankformed of substantial steel plates and arranged above the highest point of the oil circulating system. Connections to the main tank shall be at the highest point to prevent the trapping of air or gas under the main tank cover. The capacity of each conservator tank shall be adequate for the expansion and contraction of oil in the whole system under the specified operating conditions. Conservator tanks shall also be provided with a cleaning door, filling cap, drain valve with captive cap, and magnetic oil level gauges for main tank oil & OLTC oil. The conservator tank shall be so located that it does not obstruct the passage of high voltage conductors immediately above the transformer. Each conservator shall be fitted with an oil seal type breather with rubber bag and silica-gel containers sized as listed below. The breather shall be mounted at a height of approximately 1.4 meters above ground level. The breather shall be maintenance free dehydrating breather type.

2.3.3.

PRESSURE REL IEF DEVICE An approved pressure relief device of sufficient size for rapid release of any pressure that may be generated in the main and OLTC tank, and designed to operate at a static pressure lower than the hydraulic test pressure specified shall be provided. The relief device is to be mounted on the tank cover and means are to be provided to deflect gas accumulation into the Buchholz relay and not to collect in the relief device. The device shall not permit the ingress of moisture. Visible means/alarm shall be provided for indicating that the relief device has operated. Provision shall also be added to trip the HV side CB for serious conditions following oil surge. Pressure relief devices must be full covered with lateral openings for transformer tank and OLTC. The trip contacts (IP65) must be directly activated by a selflocking signal pin. Release time must be within 2ms. All important parts like trip contacts, springs, must be mounted inside.

2.3.4.

OIL HANDLING FACILITIES Each transformer shall be fitted with the following valves as a minimum requirement:

Main tank: (a) One 50 mm bore filter valve located near to the top of the tank. (b) One 50 mm bore filter valve located near to the bottom of the tank and diagonally opposite to the filter valve required against (a). (c) One 50 mm drain valve with such arrangements as may be necessary inside STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

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(d) (e) (f)

the tank to ensure that the tank can be completely drained of oil as far as is practicable. One valve for oil sampling incl. sampling facilities. Two valves for isolating both sides (in-let & out-let) of each radiator. One valve for isolating bucholz relay.

Main Conservator Tank: (e) One drain valve for oil conservator tank so arranged that the tank can be completely drained of all oil and sampling facilities. (f) One valve to cut off oil supply to the bucholz relay. OLTC Conservator Tank: (g) One valve for oil drain and sampling facilities. (h) One valve to cut off oil supply to the OLTC tank OLTC Tank: (i) Oil drain and sampling facilities. (j) One valve in oil surge relay pipe-work where appropriate. Valves shall be of the sluice type, have non-rising spindles and shall be closed by turning the hand-wheel in a clockwise direction. They shall have machined flanges and provision for locking in the closed and open positions. Details of the locking devices shall be clearly shown on the general arrangement drawing. Every valve shall be provided with an indicator to show clearly the positionof the valve, and each hand-wheel shall be fitted with a non-corrosive nameplate with engraved and filled letters or figures to provide an approved inscription which will indicate the purpose of the valve. Blank flanges, plates or captive screw caps shall be fitted to all valves and pipe ends not normally connected in service. The omission of any of, or the provision of alternative arrangements to, the aboverequirements will not be accepted unless approved in writing by the Purchaser/Engineer before manufacture.

2.3.5.

J OINT FACES All joint faces shall be arranged to prevent the ingress of water or leakage of oil with a minimum of gasket surface exposed to the action of oil or air. Oil resisting synthetic rubber gaskets are not permissible except where the synthetic rubber is used as a bonding medium for cork or similar material or where metal inserts are provided to limit compression. Gaskets are to be as thin as possible consistent with the provision of a good seal, and full details of all gasket sealing arrangements shall be shown on the Plant drawings.

2.3.6.

EARTHING TERMINALS Two earthing terminals, each capable of carrying the full lower voltage fault current for a period of not less than 30 seconds, shall be provide. They shall be located one on either side, and near to the bottom of the transformer to facilitate connection to the local earthing system.

2.3.7.

RATING PLATE The following stainless steel plates, or an approved combined plate, in accordance with General Technical Requirements (Label) shall be fixed to each transformer


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tank at an approximate height of 1.5 m above ground level:

2.4. 2.4.1.

(a)

A rating plate bearing the data specified in IEC 60076-1. This plate shall also include a space for the Purchaser's serial number

(b)

A diagram plate showing in an approved manner, the internal connections and the voltage vector relationship of the several windings with the transformer voltage ratio for each tap and, in addition, a plan view of the transformer giving the correct physical relationship or the terminals.

(c)

A plate showing the location and function of all valves and air release cocks or plugs. This plate shall also warn operators to refer to the Maintenance Instructions before applying the vacuum treatment specified in clause 2.3.1. above.

COOLING SYSTEM GENERAL All radiators shall be detachable and isolating valves shall be provided to allow removal of radiators with the transformer tank full of oil. The radiators shall be cleaned and treated in accordance with General Technical Requirements for finishing. Radiators shall be designed so that all painted surfaces can be thoroughly cleaned and easily painted in situ with brush or spray gun. The design is to avoid pockets in which water can collect. Capability of radiator to withstand the pressure test is also required.

2.4.2.

RADIATORS/FORCED AIR COOLERS CONNECTED DIRECTLY TO TANK Radiators connected directly to the tank on transformers shall be detachable. Plugs shall be fitted at the top and at the bottom of each radiator for filling and draining and an isolating valve shall be provided on the tank at each point of connection to the tank to permit removal of radiator. At the nominal power, dismantling of one of the radiators shall be possible without causing the temperature to rise above permissible values.

2.4.3.

AIR BLOWERS At nominal power, switching off one blower shall be possible without causing temperature to rise above permissible values. Air blowers for use with oil coolers shall be of approved make and design, be suitable for continuous operation out of doors and shall be capable of dealing with the maximum output and head required in service. They shall also be capable of with-standing the stresses imposed when brought up to speed by the direct application of full line voltage to the motor. Air blowers shall be complete with all necessary air ducting, and to reduce noise to the practical minimum, motors shall be mounted independently from the coolers or alternatively, an approved form of anti-vibration mounting shall be proved. It shall be possible to remove the blower complete with motor without disturbing or dismantling the cooler structure frame-work. Blades shall be of galvanized steel unless otherwise approved. Ducts and Blower casings shall be made of galvanized steel of thickness not less than 2.6 mm and shall be suitable stiffened by angles or tees. Galvanized wire mesh guards shall be provided to prevent accidental contact with


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the blades. Guards shall be designed such that neither blades nor other moving parts can be touched by the test finger illustrated in IEC 60529.

2.4.4.

COOLER CONTROL Where in multiple fan cooling usingpreferably small single-phase employed, the motors each cooling bank shall be groupedmotors so as toisform a balanced three-phase load. Each motor or group of motors shall be provided with a three-pole electrically operated contactor and with control gear of approved design for starting and stopping manually. Where forced cooling is used on transformers, provision shall be included under this contract for automatic starting and stopping from the contacts on the winding temperature indicating-device as specified in clause 2.6.1. The control equipment shall be provided with a short time delay device to prevent the starting of more than one fan, or group of fans in case of multiple-fan cooling, at a time. Where small motors are operated in groups, the group protection with alarm shall be arranged so that it will operate satisfactorily in the event of a fault occurring in a single motor. The control arrangements are to be designed to prevent starting of motors in total more than 15 kW simultaneously either manually or automatically. All contacts and other parts need periodic inspection, renewal, or adjustment shall be readily accessible. All wiring for the control gear accommodated in the marshaling kiosk together with all necessary cable boxes and terminationsand all wiring between the marshalling kiosk and the motors shall form part of the Contract Works.

2.5. 2.5.1.

VOLTAGE CONTROL GENERAL The transformers shall be provided with on-load tap changing equipment for varying the effective ratio while on load, but without producing phase displacement. The tap changer shall be connected at the neutral side of HV (primary) winding and shall be of the high-speed resistor transition type. On-load tap selectors shall be contained in separate tanks mounted in the main transformer tank through the top, in an accessible position. The same oil type will be used as for the main tank. On-load tap changers shall be suitable for specified power flow in both directions. All variables and aspects required for reliable operation at site such as step voltage, breaking capacity, rated through current, voltage class, etc. shall be fulfilled. Only design which has been type tested in accordance with IEC 60214 will be accepted. The tap selector shall be so arranged as to permit easy access for maintenance and repair of the equipment thereon, without the necessity of lowering the oil level in the main transformer tank. Oil in tap selector tanks separate from the main transformer tank shall be under a slight head of pressure from the conservator tank and the design shall ensure that any gas formation or air leaving the tap selector tanks will pass through a protection relay. Current making and breaking switches integral with the tap selector equipment


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shall be contained in a separate tank designed in a manner to make it impossible for the oil therein to mix with oil in the tap selector and main transformer. The head of oil in this tank may be maintained by a separate compartment of the main conservator or by a separately mounted tank. Oil surge detector relays and oil level gauges shall be provided. The tap changing design is still to use the conventional principle with main path and transition path, but there shall be an improvement with insertion/addition of an encapsulated vacuum interrupter/switch in each path and connected in series to each tap selector contact. The design shall eliminate the arcing process at the tap selector contacts and the arc quenching shall take place during the closing of the transition interrupter and during the opening of the main interrupter, both in each vacuum encapsulation. The interval between maintenance for tap changer with Vacuum Interrupters shall be at least 250,000operations under rated load. The service life of the mechanical gears has to be adjusted accordingly. All rotating parts shall be lubricated through grease nipples. The driving motor shall be rated for 400/230 Vac and shall be equipped with overload protection to be installed in the motor drive cubicle. Proper working of the driving motor shall be ensured even at voltages up to 25 % below the rated voltage.

2.5.2.

ELECTRICAL REMOTE CONTROL Equipment for local (manual & electrical), remote and lockable operation shall be provided in a suitable weather, vermin, and insect proof cubicle. Electrical remote control equipment shall also be supplied. The controls shall comply with the following conditions: (a)

It must not be possible to operate the electric drive when the manual operating gear is in use.

(b)

It must not be possible for two electric control points to be in operation at the same time.

(c)

Operation from the local, remote or supervisory control switch shall cause one tap movement only unless the control switch is returned to the off

(d)

(e)

position between successive operations. It must not be possible for any transformers operating in parallel with one or more transformers in a group to be more than one tap out of step with the other transformers in the group. All electrical control switches and local manual operating gear shall be clearly labeled in an approved manner to indicate the direction of tap changing.

The equipment shall be so arranged as to ensure that when a tap change has been initiated, it will be completed independently of the operation of the control relays and switches. If a failure of the auxiliary supply during tap change or any other contingency would result in that movement not being completed, an approved means shall be provided to safeguard the transformer and its auxiliary equipment. Tap changing shall be prevented when the transformer is carrying a load above a predetermined maximum or when on short circuit. Nevertheless, during switching the OLTC shall be able to withstand, without damage, the maximum short circuit current (according to circuit voltage on the HV side) attained by the proper selection of transformer impedance.


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2.5.3.

INDICATION AND ALARMS Following apparatus shall be provided for each transformer: (a)

Mechanical indication at the transformer and electrical indication at the remote control point for the number of the tap in use. The indicator at the remote control point is to show the voltage ratio in kV simultaneously with the winding tap in use.

(b)

Contacts to provide electrical indication, separate from that specified above, of tap position at the remote supervisory point.

(c)

A tap change in progress lamp at the remote control point, this indication to continue until the tap change is completed.

(d)

Alarm and indication at the remote control point with contacts for repeat alarm at the supervisory control point when the units of a group of transformers operating in parallel are operating at more than one tap apart.

(e)

Indication at the tap change mechanism of the number of operations completed by the equipment (6 digit counter).

(f)

Indication and alarm of a partial or a complete failure of the voltage transformer supply to voltage regulating relay by means of an illuminated lamp at the remote control point. The alarm shall be so arranged that it is inoperative when the circuit breaker controlling the lower voltage side of the transformer is open and also that it is disconnected when the tap changer is on control other than automatic control.

All indication devices shall operate normally at any voltage between 80% and 110% of the nominal value. Limit switches shall be provided to prevent over-running of the tap changing mechanism. These shall be directly connected in the operating motor circuit. In addition, mechanical stops shall be fitted to prevent over-running of the mechanism under any conditions. For on-load tap change equipment these stops shall withstand the full torque of the driving mechanism without damage to the tap change equipment. Thermal devices or other approved means shall be provided to protect the motor and control circuit, this equipment shall be mounted in the transformer marshalling cubicle. A permanently legible lubrication chart shall be provided and fitted inside the tap change mechanism chamber.

2.5.4.

AUTOMATIC VOLTAGE CONTROL Approved means shall be provided for automatically maintaining within adjustable limits, a predetermined voltage at the secondary voltage bus-bars. Control switches shall be provided to select remote or local direct electrical control, or automatic or non-automatic remote control. It must not be possible to operate any tap changer by remote or local (electrical/hand) control while the equipment is switched for automatic operation. For automatic voltage regulation an electronic voltage regulator shall be supplied for each transformer suitable for voltage regulation without hunting. The regulators shall be installed in the control board and meet the following minimum requirements: Sensitivity Response time value

+/- 0.4 to 6 % of transformer voltage 0.15 to 4 min. referred to 1 % deviation from desired


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Range of set point Current-response raising of set point Limitation of current effect

90 to 115 % Un(adjustable) 0 to 16 % Un

Overvoltage Umax. UndervoltageUmin. Overcurrent Imax.

100toto100 136%%Un Un 50 60 to 120 % In

0 to 16 % Un

The voltage regulator shall contain at least the following main items: Match transformer, rms. converter with integrator, limiter stages for higher and lower, set point adjuster, timing stages for command duration, amplifier, current compensation, compensation limiting, max. and min. limiter stages, auxiliary voltage transformer. Voltage drop compensation for the active and reactive voltage component shall be provided. In addition, the voltage regulators shall be provided with a manual/auto selector. The regulators will be installed in the separated Remote Regulating Control Panel in the control room.

Parallel Operation: If specified in the Schedule of Technical Particulars and Guarantee, the transformer for each substation shall be designed identical to and able to be operated in parallel with the existing one. For transformers to be operated independent/master/follower control.

in

parallel

the

control

shall

permit

All equipment necessary for this purpose shall be included in the offer/contract.

2.5.5.

VOLTAGE REGULATION REL AY Automatic voltage control shall be initiated by a voltage regulating relay of an approved type and suitable for flush mounting. The relay shall operate from the nominal reference voltage of 57.7 V derived from a voltage transformer in the transformer secondary having Class 0.5 accuracy to IEC 60186. The relay bandwidth shall preferably be adjustable to any value between 1.5 times and 2.5 times the transformer tap step percentage, the nominal setting being twice the transformer tap step percentage. The relay shall be insensitive to frequency variation between the limits of 47 Hz and 51 Hz. The relay shall be complete with a time delay element adjustable between 10 and 120 seconds. The relay shall also incorporate and under voltage blocking facility which renders the control inoperative if the reference voltage falls below 80% of the nominal value with automatic restoration of control when the reference voltage rises to 85% of nominal value.

2.5.6.

REMOTE CONTROL PANEL Remote regulating control cubicle shall be provided for each transformer, separated from the 150 kV switchgear IED control. Each shall be equipped to provide the control features specified and in addition shall be equipped with voltmeters for indication of the voltage at the HV & LV terminals of the transformer. Auxiliary switches, relays, changeover switches and terminations as necessary for the following supervisory control shall be provided:


147


A.

Indication and Alarm

(i)

Tap position indication

(ii)

Auto/manual control indication.

(iii)

Tap changecontrol 'on substation local' indication.

(iv)

Coolers on/off indication

(v) Annunciator for individual alarms and individual tripping of transformer protection

B.

Control

Tap change raiser/lower in either auto or manual conditions (the auto/manual selector switch is to transfer the supervisory control channel to the appropriate automatic or manual control).

2.5.7.

MARSHALLING BOX A marshalling cubicle shall be provided for the ancillary apparatus of each transformer. The cubicle shall contain: (a) Temperature indicators, test links and ammeter for the winding temperature indicator circuits in accordance with Clause 2.6.1. (b)

Control and protection equipment for the tap change gear including an isolating switch in the incoming circuit capable of carrying and breaking the full load current of the motor and of being locked in the open position. Provision shall also be made for termination of secondary wiring of current transformers where specified.

(c)

Terminal boards and gland plates, for incoming and outgoing cables.

Temperature indicators shall be so mounted that the dials are not more than 1700 mm from ground level and the door(s) of the compartment shall be provided with glazed windows of adequate size to permit the indicators to be viewed without opening the door(s). The temperature indicators shall be removable complete with capillary tubing and bulbs without disturbance to other apparatus. Mechanical protection shall be provided and sharp bends avoided where the capillary tubes enter the kiosks. All internal wiring shall be in conduits cleated near the side of the cubicle and so placed as not to obstruct access. All incoming cables shall enter from the bottom and must be bounded with stainless cable tie. Removable cable gland plates shall be provided and sufficient free space shall be allowed for 15 percent excess cables beyond those to be accommodated initially. All three-phase relays, contactors, isolating switches and thermal devices shall be marked with appropriate phase colours. Apparatus in which the phase elements are mounted horizontally shall be coloured red, yellow, black from left to right when viewed from the front of the panel, and when mounted verticallytheyshall be coloured red, yellow, black from top to bottom. The kiosk shall be fitted with a 15 ampere, 2 pole and earth switched socket outlet of approved design for 230 volts ac supply. It shall be mounted externally to provide auxiliary supply and shall be connected to the cubicle heater supply circuit through a 15 ampere fuse in the 'live' lead.


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2.5.8.

CONTROL PRINCIPLE Open circuit current system, i.e. the coil (relay) is energized when the contact open. The contacts shall be suitable for use in DC 110 V circuit.

2.6.

PROTECTIVE DEVICES

2.6.1.

TEMPERATURE INDICATING DEVICE Each transformer shall be provided with 3 (three) approved devices for indicating the hottest spot temperatures of primary & secondary windings and oil. Each device shall have a dial type indicator and, in addition, a pointer to register the highest temperature reached. On each device two separate sets of contracts shall be fitted, one of which shall be used to give an alarm and the other to trip the associated circuit breakers. The sets of contacts on the first device shall be connected in parallel with those on the second device and will be used to activate the cooling fans. To simulate indication of the hottest spot temperature of the windings each device shall comprise a current transformer associatedwith one phase only and a heating device designed transformer c.m.r. current together withtoa operate sensingcontinuously bulb installedatin130 an percent oil tight of pocket in the transformer top oil. One CT shall be installed in each winding termination. The tripping contacts of the winding temperature indicators shall be adjustable to close between 80 ºC and 150 ºC and to re-open when the temperature has fallen by not more than 10 ºC. The alarm and cooling fan contacts shall be adjustable to close between 50 ºC and 100 ºC and to re-open when the temperature has fallen by a desired amount between 15 ºC and 30 ºC. All contacts shall be adjustable to a scale and must be accessible on removal ofthe cover. alarm and trip circuit contacts shall be suitable for making or breaking 150 VA between the limits of 30 volts and 250 volts ac or dc and of making 500 VA between the limits of 100 and 250 V dc. The temperature indicators shall be housed in a tank mounted cubicle and shall be so designed that it is possible to move the pointers by hand for the purpose of checking the operation of the contacts and associated equipment. The working parts of the instrument shall be made visible by the provision of cut-away dials and glass-fronted covers. Terminals, links and a 63 mm moving iron ammeter shall be provided in the marshalling kiosk for each temperature indicator for: a)

Checking the output of the current transformer.

b)

Disconnecting the bulb heaters from the current transformer secondary circuit to enable the instrument to be used as an oil temperature indicator.

A diagram and instruction plate showing the connections of devices and arrangement of the CT's etc. shall be provided inside the marshalling kiosk. Maintenance instructions shall be included to show: i)

The heater coil current and temperature indicator reading when the transformer is operating at CMR with a top oil temperature of 55ºC.

ii)

The current injected from an external source and the indicator reading when the transformer is isolated and when the oil temperature is 20 ºC.


149


2.6.2.

BUCHOLZ RELAY Each transformer shall be fitted with gas and oil-actuated relay (Bucholz relay) equipment having alarm contacts which close on collection of gas or low oil level, and tripping contacts which close on following oil surge conditions. Each gas and oil-actuated relay for main and OLTC oil shall be provided with a test cock to take a flexible pipe connection for checking the operation of the relay. To allow gas to be collected at ground level, a pipe shall be connected to the gas release cock of the gas and oil-actuated relay and brought down to a point approximately 1.4 m above ground level, where it shall be terminated by a cock which shall have provision for locking to prevent unauthorized operation. A straight run of pipe shall be provided for a length of five times the internal diameter of the pipe on the tank side of the gas and oil-actuated relay and three times the internal diameter of the pipe on the conservator side of the gas or oil-actuated relay. The design of the relay mounting arrangements, the associated pipe-work and the cooling plant shall be such that mal-operation of the relays will not take place under normal service conditions. The pipe-work shall be so arranged that all gas arising from the transformer will pass into the gas and oil-actuated relay. The oil circuit through the relay must not form a delivery path in parallel with any circulating oil pipe, nor is it to be teed into or connected through the pressure relief vent. Sharp bends in the pipe-work shall be avoided.

2.7.

DRYING OUT All transformers shall be dried by an approved method at the manufacturer's works and so arranged that they may be put into service without further drying out on site. The Supplier shall submit to the Purchaser/Engineer for approval, details of the recommended method for drying out the transformers on site should it prove necessary to do so. Clear instructions shall be included in the Maintenance Instructions regarding any special precautionary measures (e.g, strutting of tap changer barriers or tank cover) which must be taken before the specified vacuum treatment can be carried out. Any special equipment necessary to enable the transformer to withstand the treatment shall be provided with each transformer. The maximum vacuum which the complete transformer, filled with oil, can safely withstand without any special precautionary measures being taken is also to be stated in the Maintenance Instructions.

2.8.

BUSHING INSULATORS The outdoor type bushing insulators shall comply with IEC 60137. The minimum creepage distance for outdoor bushings shall be very heavy degree of pollution for coastal and industrial area, while for other locations shall be heavy degree of pollution (refer to Book A I Clause 1.2). Bushings shall be of sealed construction, but attention is particularly drawn to the very humid conditions at Site and in addition, to the very rapid cooling of equipment exposed to direct sunlight when this is followed by sudden heavy


150


rain-storms. The Bidder may be required to prove satisfactory hermetic sealing by special test of each bushing type. Typical sections of bushing insulators showing the internal construction, method of securing the top cap, and methods of sealing or breathing shall be provided. 52 kV (and above) bushing insulators shall be resin impregnated paper type and there is to be no communication with the oil in the transformer. All porcelain shall be sound, free from defects and thoroughly vitrified. The glaze must not be depended upon for insulation. The glaze shall be smooth, hard, of a uniform shade of brown and shall cover completely all exposed parts of the insulator. Outdoor insulators and fittings shall be unaffected by atmospheric conditionsdue to weather, proximity of the coast, fumes, ozone, acids, alkalis, dust or rapid changes of air temperature between 15 ºC and 65 ºC under working conditions. The porcelain must not engage directly with hard metal and where necessary, gaskets shall be interposed between the porcelain and the fittings. All porcelain clamping surfaces in contact with gaskets shall be accurately ground and free from glaze. All fixing material used shall be of suitable quality and properly applied and must not enter into chemical action with the metal parts or cause fracture by expansion in service. Cement thickness is to be as small as and as even as possible and proper care is to be taken to center and locate the individual parts correctly during cementing. The shed profile of all porcelain insulators shall be plain and designed to facilitate cleaning. Special precautions shall be taken to exclude moisture from paper insulation during manufacture, assembly, transport and erection. The surfaces of all paper insulators shall be finishedwith approved non-hygroscopic varnish which cannot easily be damaged. Each porcelain bushing or insulator, and resin impregnated paper bushing, shall have marked upon it the manufacturer's identification mark and such other mark as may be required to assist in the representative selection of batches for the purposes of the sample tests stated in the schedule of Tests. These marks shall be clearly legible and visible after assembly of fittings andshall be imprinted and not impressed. For porcelain pads the marks shall be imprinted before firing and for paper bushings before varnishing. When a batch of insulators bearing a certain identification mark has been rejected, no further insulators bearing this mark shall be submitted and the Supplier shall satisfy the Purchaser that adequate steps will be taken to mark or segregate the insulators constituting the rejected batch in such a way that there can be no possibility of the insulators being resubmitted for the test or supplied for use of the Purchaser. Bushing insulators shall be mounted on the tank in a manner such that the external connections can be taken away clear of all obstacles. Neutral bushings shall be mounted in a current positiontransformer from whichwill a connection be this takencontract, to the transformer tank. The be suppliedcan under provision shall be made on the tank for mounting to the Purchaser/Owner's requirements. A flexible pull-through lead suitably sweated to the end of the winding copper shall be provided for 150 kV voltage bushings and is to be continuous to the connector which is housed in the helmet of the bushings. When bushings with an under-oil end of a re-entrant type are used, the associated STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

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flexible pull-through lead is to be fitted with a suitably designed gas bubble deflector. The bushing flanges must not be of re-entrant shape, which may trap air. Clamps and fitting made of steel or malleable iron shall be galvanized and all bolt threads shall be greased before erection. Every HV bushing shall be completed with online monitoring (tan δ and capacitance) with Fail-Safe safety feature. Online monitoring shall be done through test tap according to IEC 60137. The connection to test tap shall be accessible from bushing flange through online monitoring device that shall be fit on properly manner with test tap. The test tap is connection, accessible from outside the bushing, insulated from the flange or other fixingdevice, made to one of the outer conducting layers of a capacitance graded bushing in orderto allow measurements of dissipation factor, capacitance and partial discharge whilst theflange of the bushing is earthed NOTE 1 This connection should be earthed directly when it is not used. NOTE 2 When the test tap is used for condition monitoring, in service, care should be taken to avoid an opencircuit.

2.9.

CABLE TERMINATIONS Cable boxes and sealing end chambers shall be designed to accommodate all the cable joint fittings or sealing ends required by the manufacturer of cables, including approved means of controlling the voltage stress of the terminal insulation of cables.

Oil filled cable sealing end chambers shall be provided with removable links for testing purposes. The chamber shall have a removable cover and the design of the chamber is to be such that ample clearances are provided to enable either the transformeror each cable to be subjected separately to high voltage tests. The oil level in the sealing end chambers shall be maintained from the main conservator tank by means of a connection to the highest point of the chamber, this connection shall be controlled by suitable valves. A connection to the conservator shall be made so that any gas leaving the chamber must pass through the gas and oil- actuated relay. An earthing terminal shall be provided in each disconnecting or sealing end chamber to which the connections from the transformer winding can be earthen during cable testing. The medium voltage cable boxes and disconnecting or sealing end chambers shall be capable of withstanding for 15 minutes both at the time of the first test on the cables and at any subsequent time as may be required between phases & to earth a test of 48 kV dc or 32 kV ac. During these tests the links in the disconnecting or sealing end chamber or cable box will be withdrawn and the transformer windings with connections thereto will be earthen. All cable boxes and disconnecting chambers shall have oil-tight joints and are to be tested with oil having a viscosity not greater than that of insulating oil when at a temperature of 15ºC at a pressure of 6.87 N/sqcm for 12 hours, no oil leakage is to occur and no permanent deformation is to take place in the structure.


152


2.10.

CABLES AND TERMINATIONS

2.10.1. CABL E BOXES AND SE ALING END CHAMBERS For GIS (if any), facilities shall be provided at the transformer primary/HV side for terminating insingle XLPE The Cu cable (of specified dimension) cables perbushing phase individually cable core end boxes. end boxes and the transformer specified shall be interchangeable. Means shall be provided on the transformer tank side for supporting cables. All cable boxes shall have oil-tight joints and are to be tested with oil having a viscosity not greater than that of IEC 60296 insulating oil when at a temperature of 15 ⁰C at a pressure of 69 kN/sqm for 12 hours, no oil leakage is to occur and no permanent deformation is to take place in the structure.

2.10.2. DISCONNECTING CHAMBERS Where specified in the schedule of technical particulars, an oil-filled cable disconnecting chamber with removable links shall be provided for testing purposes. Barriers shall be provided on both sides of the disconnecting chamber to prevent ingress of the oil used for filling the chamber into the cable box or the transformer. It must only be necessary to remove part of the oil in the chamber itself when making the necessary testing connections.

The disconnecting chamber shall have a removable cover and the design of the chamber is to be such that ample clearances are provided to enable each cable to be subjected separately to high voltage tests. The oil level in the disconnecting chamber shall be maintained from the main conservator tank by means of a connection to the highest point of the chamber and this connection shall be controlled by suitable valves. A connection to the conservator shall be made so that any gas leaving the chamber must pass through the gas and oil-actuated relay. An earthing terminal be provided disconnecting sealing end chamber to which theshall connections from in theeach transformer windingorcan be earthen during cable testing.

2.10.3. TESTING The cable boxes and disconnecting or sealing end chambers shall be capable of withstanding for 15 minutes both at the time of the first test on the cables and at any subsequent time as may be required, between phases and to earth a test voltage equal to: 2E kV DC or an AC test equal to 1.3E kV Where:

E = system voltage between phases in kV(rms).

During these tests the links in disconnecting or sealing end chamber or cable box will be withdrawn and the transformer windings with connections thereto will be earthen.

2.10.4. SUPP LY OF CABL ES Auxiliary power and multi-core control cables between the all parts/equipment of the transformer contract (among transformer, marshalling kiosk or tank mounted cubicle, remote regulating control panel, fire protection system (if any, ancillary STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

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equipment) shall be installed, glanded and have individual cores identified and terminated under this Contract. Cables from each transformer scope to auxiliary supply switchboards and interconnections with other transformers will be supplied, glanded and have individual cores identified and terminated under this Contract. Supply of cables shall be of the shielded/armoured type with sufficient dimensions and subject to approval.

2.11.

SP ARE PA RTS FOR S/S TRANSFORMERS The following typical set of spare parts and other special tools (if any) shall be proposed separately as optional and to be quoted with appropriate quantity in the schedule of recommended spare parts in the Bidding Document – Book C: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19.

2.12.

HV bushing LV bushing HV neutral bushing LV neutral bushing TV bushing Gaskets Thermometers Oil level indicators Motor for tap changer Cooling fan with motor Buchholz and OLTC relays AVR incl. voltage regulation relay Magnetic contactors & auxiliary relays Molded-case breaker Contact elements of tap changer diverter switches Valves and plugs Silicagel for dehydrating breather Final coating paint with solvent Each kind of signal lamp

INSULATING OIL

2.12.1. FILLING WITH OIL Before filling with oil, the transformer coil assembly, tank, radiators and all internal parts shall bethoroughly cleaned of all dirt, grease and loose items. The tank shall be filled from the bottom valve under vacuum conditions with transformer oil of Uninhibited Certified Nepthanic Base and complying with IEC 60296 for acceptance tests. Certificate of Mixability Test with Shell Diala B shall be issued by PT PLN (Persero) PUSLITBANG and shall be submitted with the Bid.

2.12.2. SUPP LY OF TRANSFORMER OIL Oil shall be supplied separatelyin drums (200 litres/drum). The amount of oil shall be oversupplied sufficiently.

2.13.

PRE-APPROVED SUP PL IER LIST


154


The following suppliers have been pre-approved as acceptable suppliers for the nominated equipment at the time of preparation of this specification and evidence of satisfactory in service performance has been proven to the Purchaser’s satisfaction. Manufacturer who wishes to supply ancillary product which meet the above criteria shall provide Purchaser with a proposal which contains complete specification, Material Safety Data Sheet for the product, a statement with assessment of in-service performance and a reference list of users who can attest to the claimed in-service performance. The proposal is subject to Purchaser’s approval.

NO

COMPONENT / ACCES SORIES

VENDOR

1

Silicon Steel

2

Copper Wire

AK Steel POSCO Steel Nippon Steel ThyssenKrupp Steel Asta Metrod

COUNTRY OF ORIGIN USA Korea Japan Germany China Malaysia

3 4

OLTC Insulation Paper and transformer Board

5

RIP Bushings

6

Non-Condenser Bushing

7

Buchholz Relay

Essex MR – Vacutap Weidmann Munksjö Pucaro TRENCH HSP ABB – Micafil ABB Components NGK HSP Knobel Cedaspe EMB

China Germany Switzerland, China Sweden Germany France, Switzerland Germany Switzerland Sweden Japan Germany Germany Italy Germany

8

Pressure Relief Device

9

Rubber Bags

10

Dehydrating Breather

Italy Germany USA France Japan Germany

11

Cooling Fan

12

Fiber Optic Thermometer

13

WTI/OTI

COMEM MESSKO Qualitrol Pronal Fujikara MESSKO-MTRAB COMEM Ziehl-Abegg Krenz Neoptix Luxtron MESSKO AKM Qualitrol

14

Conservator Oil Level Indicator

Italy Germany USA

15

Insulating Oil

COMEM MESSKO Qualitrol Nynas Libra Shell Diala B Total

Germany USA Canada USA Germany Sweden USA


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2.14.

PREP ARATION FOR TRANSPORT On completion of the work test and inspection the transformersshall be drained of oil, bushings and accessories removed and prepared for transport. The transformer tanks shall be completely sealed and filled with Nitrogen. The Nitrogen pressure shall be maintained with a pressure bottlefitted with a pressure valve and secured to the side of the transformer. A reserve bottle of Nitrogen shall be piped up to the system.

2.15.

TESTS Tests shall be made at the manufacturer’s works. All external components and fittings that are likely to affect the performance of the transformer during the test shall be in place. All measuring systems used for the tests shall have certified, traceable accuracy and be subjected to periodic calibration. The manufacturer shall provide the copy of calibration certificates before the testing begins. COMPLETED TRANSFORMER Routine, type and special tests shall be carried out in accordance with IEC 60076 and summarized as the following:

NO

TESTS ITEM

TEST METHOD STANDARD

PL N ACCEPTAN CE CRITERIA *)

ROUTINE TEST IEC 60076-1 ±0,5% of declared ratio 1 Voltage Ratio and Phase Displacement (clause 10.3) Check IEC 60076-1 2 Winding Resistance (clause 10.2) IEC 60076-1 • Load Loss: Max +10% from 3 Load Loss and (clause 10.4 Impedance Voltage guaranteed value and 10.7) • ±7,5% of declared impedance • Impedance measurement on all tappings IEC 60076-1 • +10% from guaranteed no4 No-Load Loss and (clause 10.5) no-load current load loss value • +30% of the declared noload current value IEC 60076-1 Less than the guaranteed 5 Harmonics of The (clause 10.6) value No-Load Current IEC 60076-1 Sequence of operations shall 6 Test on On-Load (clause 10.8) be performed without failure Tap Changer IEEE C57 7 Measurement of Insulation Resistance of The STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

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NO

8 9 10

11

12

TESTS ITEM Windings Polarization Index Dielectric Test of Core to Earth Separate Source Voltage Withstand Test Short-duration AC withstand voltage test (ACSD), phaseto-earth test Short-duration AC withstand voltage test (ACSD), phaseto-phase test with earthed neutral (Partial Test) Discharge

13

15 16

17

Determination of Capacitances windings-to-earth and between windings, and Tan δ of The Windings Functional Test of Accessories Dielectric Test of Auxiliary Wiring to Earth Lightning Impulse Test

TEST METHOD STANDARD


IEEE C57 IEC 60076-3 No collapse of the test voltage occurs IEC 60076-3 (clause 12.3)

•

No collapse of the test voltage occurs

IEC 60076-3 (clause 12.3)

•

No collapse of the test voltage occurs The continuous level of ‘apparent charge’ at U2 during the second 5 min

•

does not exceed 70 pCon all measuring terminals • The partial discharge behavior does not show a continuing rising tendency IEC 60076-1 Tan < 0.5% IEEE C57

-

-

IEC 60076-1 No collapse of the test voltage occurs

IEC 60076-3

•

•

18 19

20

SFRA Measurement Breakdown Voltage and Dissipation Factor of The Insulating Oil Dissolved Gas Analysis

The test impulse shall be a full standard lightning impulse: 1,2 s ± 30 %/50 s ± 20 % The absence of significant differences between voltage and current transients recorded atreduced voltage and those recorded at full test voltage constitutes evidence that the insulationhas withstood the test.

IEC 60156 and IEC 60247 IEC 60599


157


NO 21

TESTS ITEM Oil Leakage / Pressure Test

22

Measurement of Power Taken by Fans 23 Measurement of insulation paper DP value TYP E TEST 1

Temperature Rise Test

2

Noise Level Test

3

Measurement of Zero Sequence

4 5

TEST METHOD STANDARD -


IEC 60076-1 +10% from guaranteed value DP > 900, measured on paper sample after drying process

IEC 60076-2 Hot Spot Temperature Rise < 68 K measured by fiber optic sensor IEC 60076- Less than guaranteed value 10 IEC 60076-1

Impedance Auxiliary Losses Vacuum Test

-

*) based on SPLN, O&M Standard, and best practices The tapping connection to be used for the impulse tests shall be the one on which the highest voltage stresses occur. Verification of the correct choice of tapping shall be provided. Impulse tests shall be applied by direct application to each line terminal in turn except where, by agreement with the Engineer, the transferred surge method of test may be adopted for tests on lower voltage windings. The tapping connection to be used for the impulse tests shall be the one on which the highest voltage stresses occur. Verification of the correct choice of tapping shall be provided. Impulse tests shall be applied by direct application to each line terminal in turn except where, by agreement with the Engineer, the transferred surge method of test may be adopted for tests on lower voltage windings. VOLTAGE CONTROL EQUIPMENT: Routine Tests - each finished tap changer is to be subjected to the mechanical and dielectric routine tests specified in IEC 60214. Type Tests - to IEC 60214 or type test certificates submitted in lieu. BUSHINGS: Routine, type, sample and special tests shall be carried out in accordance with IEC 60137. The following special test shall be made: Short time current test: Each type of bushing being provided shall be subjected to a short time current test of 3 seconds at the fault rating specified in the schedule of technical particulars, the test procedure being in accordance with that of IEC 60056. CABLE BOXES AND DISCONNECTING CHAMBERS:


158


Routine test: Oil tightness - All cable boxes and disconnecting chambers shall be tested with oil, having a viscosity not greater than that of IEC 60296 insulating oil when at temperature of 15 °C, at a pressure of 70 kN/m² for 12 hours; during this time no leakage shall occur nor shall there be any permanent set when the pressure is released. TANKS AND COOLERS: Routine tests: Oil leakage: All tanks, conservators and oil filled compartments including all forms of radiator shall be tested, before painting, for oil tightness by being completely filled with oil of a viscosity not greater than that of IEC 60296 insulating oil at a temperature of 15 °C and subjected to a pressure equal to the normal pressure plus 35 kN/m². This pressure shall be maintained for a period of not less than 24 hours, during which time no leakage shall occur. The tap changer barrier shall be subjected to normal oil pressure head for 24 hours, during which time there shall be no leakage from the panel or bushings. Type tests: Unless type test certificates can be produced for test carried out on similar equipment, the following tests shall be done for tank, conservator, radiator and pressure relief device: Vacuum test: The equipment shall be subjected to a vacuum of 508 mm of mercury less than atmospheric pressure when empty of oil. The permanent deflection of plates or stiffeners on removal of vacuum is not to exceed the following values.

Major dimension of plate between stiffeners Less than1300 mm 1300 to 2500 mm Greater than 2500 mm

Max permanent deflection

3 8 12.7

mm mm mm

Pressure test: The equipment is to withstand pressure corresponding to normal pressure plus 35 kN/m² for 12 hours. The permanent deflection of plates or stiffeners on removal of pressure is also not to exceed the values stated in respect of the vacuum test in the above table. This test may be combined with a routine oil leakage test. The tap changer barrier shall be shown to withstand an over pressure test of normal pressure plus 35 kN/m2 for 12 hours. For pressure release device, it shall be subjected to increasing oil pressure and shall operate just slightly before reaching normal pressure plus 35 kN/m². The operating pressureshall be recorded on the test certificate.


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COOLING PLANT WITH FORCED OIL CIRCULATION Routine tests: Air/oil coolers: All coolers using forced oil circulation shall be filled with oil of a viscosity not greater than that of IEC 60296 insulating oil at a temperature of 15 °C and subjected to a pressure equal to twice the maximum working pressure at the inlet to the cooler under service conditions which shall be maintained for a period of not less than 24 hours; during this time no leakage shall occur. Water/oil coolers: The oil and water compartments of all water cooled oil coolers shall be tested separately to withstand a hydraulic pressure of 350 kN/m2 for 15 minutes after which the pressure shall be reduced to twice the maximum working pressure at the inlet to the cooler under service conditions and shall be maintained for a period of not less than 24 hours during which time no leakage shall occur. Type tests: One forced-oil of each type shall be subjected, when empty of oil, to that vacuum test level specified. There shall be no permanent deformation or distortion of any part of the cooler. PUMPS, MOTORS, PIPE WORK, OIL SAMPLING DEVICES AND VALVES Routine tests: Oil filled equipment: The bodies of all oil pumps complete with submerged motors, if any, and the oil pipe work, oil sampling devices and valves shall withstand a hydraulic pressure of 140 kN/m2 for 15 minutes.

Water filled equipment: Water pumps, water pipe work and valves shall withstand a hydraulic pressure of 700 kN/m2 for 15 minutes after which the pressure shall be reduced to twice the maximum working pressure, at the inlet to the cooler under service conditions and shall be maintained for a period of not less than 24 hours during which time no leakage shall occur. Control gear: All control gear shall be subjected to the tests specified inthe appropriate IEC. Motors: Each motor shall be subjected to the following tests where applicable: Measurement of winding resistance (cold). -

No load test at rated voltage for determination of fixed losses. An overvoltage test at 1.5 times rated voltage applied with the machine running at no load, for a period of 3 minutes, to test inter-turn insulation. High voltage in accordance with IEC 60034.

Type tests: Motors: Performance tests shall be in accordance with IEC 60034 however, certificates of STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

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type tests in accordance with IEC will be accepted. Except for non-return valves, all valves and oil sampling devices, which are subject in service, or during maintenance to oil pressure shall withstand, when empty of oil, absolute pressure not exceeding 350 mbars. In the case of valves this test is to be applied to the body only. This type test shall subsequently be followed by a repeat oil leakage test. OIL Sample test: Sample of oil from each consignment shall be tested in accordance with IEC 60296 before dispatch. Subject to the agreement of the Engineer a test certificate, confirming that the oil from which the consignment was drawn has been tested in accordance with IEC 60296, may be accepted. Before commissioning any reactor, the electric strength of its oil shall be check-tested and the result approved by the Engineer. GAS AND OIL ACTUATED RELAYS A.

ROUTINE TESTS: The following tests shall be made on relays when completelyassembled. Where oil is referred to it shall have a viscosity not greater than that of IEC 60296 insulating oil at 15°C. Oil leakage: The relay, when filled with oil shall be subjected to an internal pressure of 140 kN/m2 for 15 minutes. No leakage shall occur either from the casing or into normally oil free spaces, such as floats, within the casing. Gas collection: a.

With the relays mounted as in service and at a rising angle of 5 degrees (tank to conservator) and full of oil, gas shall be introduced into the relay until the gas collection contacts close. The oil level contacts shall not close when gas is escaping freely from the relay on the conservator side. These contacts shall, however, close when the pipe-work is empty of oil.

b.

The empty relay shall be tilted, as if mounted in pipe-work rising from tank to conservator, at an increasing angle until the gas collection contacts open. The angle of tilt shall then be reduced and the gas collection contacts shall close before the angle is reduced to less than 13 degrees to the horizontal.

c.

With the relay mounted at a falling angle of 16 degrees to the horizontal and full of oil, the gas collection contacts shall be open. Oil surge: With the relay mounted as in service and full of oil at approximately 15 °C, the surge contacts shall close within the steady oil flow limits specified in the schedule. This operation shall not be adversely affected when the gas collection contacts have already closed and gas is escaping freely. Voltage: With the relay empty of oil, a voltage of 2.5 kV shall be applied in turn STANDARDISASI SPESIFIKASI TEKNIS TRANSFORMATOR TENAGA

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between each of the electrical circuits and the casing for one minute, the remaining circuits being connected to the casing. Operation: With the transformer assembled with its cooling plant as in service, tests shall be made to demonstrate that the relay does not operate whilst the oil pump motors are being started or stopped. B.

SAMPLE TEST: At the discretion of the Engineers, the following tests shall be made: Variation of performance with mounting angle with the mounting conditions as in service, the mounting angle shall be varied within the rising angle limits 1° and 9° and tests repeated in the manner prescribed for the routine tests.

SECONDARY WIRING: All secondary wiring, including panel wiring and control circuits and all apparatus connected thereto shall be subjected to the following tests. Routine tests: Voltage: 2.5 kV applied for one minute. Insulation resistance: By megger of not less than 500 volts. GALVANIZING: Sample tests: Samples selected by the Engineers of all galvanizing materials shall be subjected to the galvanizing test set out in BS 443- "Testing of Zinc Coating on Galvanized Wires", or BS 729- "Testing of Zinc Coating on Galvanized Articles other than Wire", whichever is applicable. WELDING Welder’s qualification tests: All welders engaged on fabrication either in the manufacturer's works or on site and on any weld repairs subsequently found shall, before undertaking welding, satisfactorily complete procedure andnecessary qualification tests in the presence of the Engineer. The minimum requirement for the testing of welders engaged on structural steel would be as follows: Butt welds (manual): Test plates to be of average thickness for the Contract. Two test required: horizontal/vertical and vertical. From each test weld made are to be prepared one forward and one reverse bend test and one macro specimen. The bend tests are to be taken through 180 degrees over a former of diameter equal to three times the thickness of the plate. Fillet welds: The size of fillet weld must be an average of those called for on the Contract. Two tests are required: horizontal/vertical and vertical. From each test weld, nick break and macro specimens are to be prepared. Butt welds (machine welding):


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On full penetration butt welds, the first two seams welded are to be witnessed with 'run on' and 'run off' plates attached. From these plates are to be prepared a forward bend, a reverse bend and a macro. The bend requirements are as for the manual test. On partial penetration butt welds the first two seams are to be witnessed and macro specimens are to be prepared from the 'run on' and 'run off' plates in addition to the ends of the actual weld. The extent of penetration is the comply with the approved drawing. The Shop Tests shall alsoinclude the followings:

2.16.

a.

Visual checks for completeness of the equipment and accessories

b.

Functional tests on all system

c.

Interchangeability of removable elements of corresponding rating

SITE TESTS The Bidder shall implement the following procedures of site tests: a.

The Purchaser/Engineer shall be notified in writing as soon as any section of the Contract Works has beencompleted and ready for site testing. Site test program is to be prepared and approved by the Purchaser/ Engineer to satisfy the requirements and operating conditions of the Purchaser's system.

b.

The tests shall be carried out by the Bidder in cooperation with and in the presence of the Purchaser/Engineer. Additional tests that may be required by the Purchaser/Engineer have also to be carried out to prove that the equipment has the capacity to work under the most onerous site conditions. Subject to agreement the tests could be carried out by the Purchaser and supervised by the Manufacturer's site supervisor(s). Certificates and records of the Purchaser/Engineer for approval.

c.

tests

shall

be

submitted

to

the

The Bidder's representative must be present when any item of equipment is made alive for the first time.

Minimum acceptable site tests: The tests shall include, but not limited to the followings: -

Visual checks for completeness of the equipment and accessories.

-

Point-to-point wiring continuity check on all circuits to confirm the final connections agree with the panel wiring diagrams.

-

Insulation resistance of all secondary circuits.

-

Insulation resistance of core and windings.

-

Insulation resistance between core and tank.

-

Insulation resistance test on bushings.

-

Sweep Frequency Response Analyzer (SFRA) test.

-

Tan Delta test.

-

Dielectric strength of oil samples. Ratio and no-load current at low voltage (e.g. 400V) on all tapping.


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-

Vector/Phase relationship test.

-

Polarity tests and where feasible magnetism characteristics on transformers.

-

Calibration check of temperature instruments, including secondary current injection and proving contact settings.

-

Check operation of all relays, instruments, alarms and trips. Air injection tests of gas/oil-actuated relays.

-

Setting check of oil-level, oil-flow devices.

-

Complete functional tests of cooling equipment and tap change equipment, including manual/automatic sequences, indications, alarms and interlocks, measurement of motor currents, adoption of suitable motor protection settings and proof of protection operation for stalled or single phasing conditions.

-

Operational test “maintenance free dehydrating” type breathers.

-

Functional testing of all equipment.

-

Final checks before energizing: Venting, position and locking of valves, earthing of star-point(s) and tank, state of breathers and pressure-release devices, oil levels, absence of oil leakage, operation of kiosk heaters, resetting of maximum temperature indicators, final proving of alarms and trips.

-

Energizing of all circuits.

-

Tests when energized: OLTC operation throughout range (subject to not exceeding 1.1 p.u. volts on any winding) and maintenance of 1.1 p.u. volts on untapped windings for 15 minutes (but not exceeding this value on tapped winding).

-

Tests on load: Temperature instrument readings and measurement of WTI CT secondary currents.

-

Other tests that required for commissioning


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BAB 6 Buku Standardisasi Spesifikasi Teknis Transformator Tenaga 30MVA (SK DIR NO.0632.K-DIR-2013)

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