GE SR345 Instruction Manual page 172

S2 SYSTEM SETUP
6–60
Courtesy of NationalSwitchgear.com
MAGNITUDE, PHASE ANGLE, AND ZERO SEQUENCE COMPENSATION
Transformer magnitude, phase angle, and zero-sequence compensation calculations
Complete magnitude, phase angle, and zero sequence compensation is as follows:
Winding 1 compensated currents:
Winding 2 compensated currents:
where:
- magnitude, phase and zero sequence compensated winding w phase currents
- magnitude compensation factor for winding 2 (see previous sections)
- phase and zero sequence compensated winding phase currents (see earlier).
In our example, the following phase and zero-sequence compensation equations would
be used:
For Winding 1 (Wye – grounded neutral):
For Winding 2 (Delta):
The complete compensated winding 1 and winding 2 currents would be as follows:
345 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 6: SETPOINTS