Motor Starting Study Exercise 1. Exercise 1: System Setup – additional data for MS based on SC study files • Source and Branch Parameters Same as load flow and short-circuit studies. •
Switching Motor Data for Static MS Element Accel T Accel T No Load Full Load
Mtr 1 Mtr 2 Syn 1
2 1 2
St Load*
Final Load
T Begin
T Final
100 100 25
100 100 90
0 0 1
0 0 5
4 2 4
* Set starting category data for Category 1, 2, and 3. * Check data for Mtr4 and Mtr5. •
Switching Motor Data for Dynamic Acceleration MS Element
Mtr 1 Mtr 2 Syn 1
Mtr Model *
Load Model
Single 2, HV-HS-LT, MV500HP2P Charac., LV-HS-HT, LV200HP2P Single 2, HV-HS-HT, MV1000HP2P
FAN a k**3 Recip. Comp
* In Motor Parameter Update Dialog, uncheck all boxes. •
Starting Category Element Normal Back Up
ETAP Workshop Notes 5.0
Mtr Model Mtr 1, Mtr 4 Mtr 2, Mtr 3
Page 1 of 5
H 0.4 0.2 .5
Motor Starting Study Exercise 2. Exercise 2: Motor Starting Case 1 • Set up Study Case: MSCase-1 • Using Design Load, No load diversity factor. • Run simulation for 15 Seconds. • Include XFMR LTC in Pre-starting Load Flow, not during simulation. • Acceleration motor model based on Mechanical Load. • Use default settings on Adjustment and Alert Pages. Check all alert options with minimum violation span = 0.2 second. • Use Normal configuration. • Action sequence: Time 0.2 second
Study Case: MSCase-1 Parameter Setting Start Mtr 5, at 60% load and ramp load from 60% to 100 % in 3 seconds. Switch on static load Load 2, Loading Category: Design
3 second
Start all motors in the system belong to Normal Category
•
Run Static Motor Starting • Check results from OLV display, plot and report. • Is system voltage ok? Is the problem real or is it related to user entered acceleration time and sequencing?
•
Run Dynamic Motor Starting • Check results from OLV display, plot and report. • Is system voltage ok? • Can all the motors be started? • Solution to solve problem with motors failing to start (to increase acceleration torque): • Change starting sequence • Change pre-starting voltage • Use XFMR LTC • Use Starting device – What type of starter should be used here? (Cap) • Use larger motor • Try to change Mtr4 Starting Load from 60% to 40% -- Can Mtr 4 be started? • Check for low voltage problem – Is there a voltage problem? How to solve it?
ETAP Workshop Notes 5.0
Page 2 of 5
Motor Starting Study Exercise 3. • • • •
Exercise 3: Starting Devices Run Dynamic Motor Starting Configuration: Tie-Open, Study Case: MSCase-1 ( Change simulation duration to 15 seconds) Check bus voltage for starting motors. (Mtr1 V < 80%) How can you solve the problem? ( Re-sequencing, start at reduced load, using starter?)
• • •
Try Using Starting Device What type of starting device to use? Try current control soft starter and Capacitor bank at motor terminal. Is it a good way of solving problem?
Speed 0 2 2 95 95 •
Current Control Setting 400% 400% 200 or 250% 400%
Type Fixed Fixed Ramp Fixed Remove
Starting Device Capacitor at Bus/Terminal Speed Setting Type 0 1000 kvar Fixed 95 Remove
Try voltage control soft starter.
ETAP Workshop Notes 5.0
Page 3 of 5
Motor Starting Study Exercise 4. Exercise 4: MOV Starting • Set up MOV data • Both MOVs have Hammer Blow. • Both MOVs do not have Micro Switch. • Both MOVs have Vlimit = 80. • T = 0.5 second for Start, Full Speed, Seating/unseating, and Stall periods. • 5 seconds for Travel period. •
Set up Study Case MSCase-2 and MSCase-3 • Using Design Load, No load diversity factor. • Run simulation for 15 Seconds. • Include XFMR LTC in Pre-starting Load Flow, not during simulation. • Acceleration motor model based on Mechanical Load. • Use default settings on Adjustment and Alert Pages. Check all alert options with minimum violation span = 0.2 second. • Use Normal configuration. • Action sequence:
3 second
Study Case: MSCase-2 Parameter Setting Start all motors in the system belongs to Backup Category Switch on static load Load 1, Design category Start OpenMOV and ClosedMOV
Time 0.2 second 3 second 5 second
Study Case: MSCase-3 Parameter Setting Switch on static load Load 1, Design category Start OpenMOV and ClosedMOV Start all motors in the system belonging to Backup Category
Time 0.2 second
•
Run Dynamic Motor Starting with MSCase-2 • Check results from OLV display, plot and report. • Check MOV starting process.
•
Run Dynamic Motor Starting with MSCase-3 • Check results from OLV display, plot and report. • Check MOV starting process.
ETAP Workshop Notes 5.0
Page 4 of 5
Motor Starting Study Exercise 5. Exercise 5: Load Transition • Set up Load data • All Motor: Design -- 100%, Normal – 90%, Winter -- 75. • All Static Load: Design -- 100%, Normal – 80%, Winter -- 90. • Mtr 1: Design -- 100%, Normal – 80%, Winter – 0%. • Mtr 2 & 3: Design -- 100%, Normal – 0%, Winter – 90%. •
Set up Study Case MSCase-4 • Using Design Load, No load diversity factor. • Run simulation for 10 Seconds. • Include XFMR LTC in Pre-starting Load Flow, not during simulation. • Acceleration motor model based on Mechanical Load. • Use default settings on Adjustment and Alert Pages. Check all alert options • Use Normal configuration. • Action sequence:
Time 0.2 second 3 second
•
Study Case: MSCase-4 Parameter Setting Switch to Normal Load Category Exclude MV loads >= 5000 kVA Switch to Winter Load Category Exclude MV loads >= 1200 kVA Exclude MV loads >= 1000 kVA
Run Dynamic Motor Starting with MSCase-4 • Check results from OLV display, plot and report. • Check bus load change. • Check if any motors are started or stopped.
ETAP Workshop Notes 5.0
Page 5 of 5
