Transformer Gen Protection

Generator protectio Relays used 50BF 87G 64R 37 59N 32R 21 60FL

Circuit Breaker Failure I Differential Protection Rotor Earth fault Low Forward Power Stator Earth fault 90%/95% Reverse Power(high/low) Min. Impedance Fuse Failure

40

Under Excitation/Loss of  Excitation/def. time protection/ +with time integrator

51N 59 81 81 50/27 46

Over current Over Voltage Frequency Stage 1 Frequency Stage 2 Inadvertand energization Unbalanced Load/negative Sequenc

Out of Step/pole slip(slip in 78 generator/slip in grid(if allowed) 24(59/81) Over Ex Excitation U/ U/F 59N( 59 N(DC DC)/ )/64 64Dc Dc DC -Volt -Voltag age e 74 TC Trip circuit supervision GCB 27 Under Voltage 49 Over Load 80 DC supply Failure 86 G Generature Lock Out 94 Trip Relay

67 59N.1/2

Directional phase overcurrent Bus earthfault protection(if cb open

n with 100% redundancy  Trip Trip Alarm/Trip/fault 64S1-90%& 64S2 100%

ok ok ok ok ok ok

Unbalance Voltage

Alarm/Trip/fault Trip Trip Alarm

1&2

alarm stat/Trip stat/Trip dyn ok

I>/I>>,over current & short circuit Max1 & Max 2

Trip Trip Trip Trip Trip max1 & Max 2(def. time/alam-inverse tialarm/trip

ok ok ok ok ok ok

loss of syncronization stg1 trip/stg2 trip Over Flux/saturation inverse time(V/Hz)Over Excitation U/F DC Earth Fault Alarm

ok

Trip

ok ok ok

ok

can be superceed in the configration GEN,GCB & T/f as taken care by 64 earth fault protection ,cbclose2)

ok

50BF 87G 64R 64G 32R 21 60FL

40

51V 59 81 81 50/27 46

78 24 59N(DC) 74 TC 27

Circuit Breaker Failure II Trip Differential Protection Trip Rotor Earth fault+Sensitive Rotor E/F Alarm/Trip/fault Low Forward Power Stator Earth fault 100% Alarm/Trip/fault Reverse Power Trip Impedance Trip Fuse Failure Alarm

Under Excitation

alarm stat/Trip stat/Trip dyn voltage restrained overcurrent protection

Over current Over Voltage Frequency Stage 1 Frequency Stage 2 Inadvertand energization Unbalanced Load

Trip Trip Trip Trip Trip alarm/trip

Out of Step Over Excitation U/F DC -Voltage Trip circuit supervision GCB Under Voltage

stg1 trip/stg2 trip Over Excitation U/F Alarm

Step up Transformer-BAT Buchholz Relay Pressure Relief Device OLTC 22O KV Substation Protection chan 2 Fire Protection From Generator Protection chan 2 Winding Temp. Oil Temp.

Trip Trip

Unit Aux. Trans-BBT 63T

49T 26T

Buchholz Relay Pressure Relief Device Fire Protection Winding Temp. Overload device Oil Temp.

Unit Aux. 90T Trip Trip Trip Trip Trip 71T

BAT 870A 50/51 50/51N 50/51 50/51N 50/51 50/51N

Differential Overcurrent 1 phas breaker failure Over current 1 Ie>Ie>> Overcurrent 2 phase Over current 2 Ie>Ie>> Overcurrent 3 phase Over current 3 Ie>Ie>> 27 under voltage 59 Over Voltage 59N Bus Earth Fault-Over Voltage 24/(59/81) Over Excitation U/F-Over flux

Trip Trip Trip Trip

Alarm Alarm/Trip

870A 50/51 50/51N 50/51 50/51N 50/51 50/51N 87N 59N 24

Buchholz Relay Pressure Relief Device OLTC 22O KV Substation Protection chan1 Fire Protection From Generator Protection chan 1 Winding Temp. Oil Temp.

Trip Trip Trip Trip Trip Trip Trip Trip

rans-BBT NLTC Buchholz Relay Pressure Relief Device Fire Protection Winding Temp. Oil Temp. OIL LEVEL

Trip Trip Trip Trip Trip Trip

Differential Overcurrent 1 phase Over current 1 Ie>Ie>> Overcurrent 2 phase Over current 2 Ie>Ie>> Overcurrent 3 phase Over current 3 Ie>Ie>> Restricted E/F 1

Trip Trip

Bus Earth Fault Over Excitation U/F

Alarm

Trip