Anti-Motoring (Reverse Power) - GE DGP Series Instruction Manual

2 CALCULATION OF SETTINGS
C2
Figure 2–7: MHO CHARACTERISTICS FOR 40-1 & 40-2 FUNCTIONS
The 32-1 and 32-2 anti-motoring reverse power level settings 804: REV PWR and 903: REV PWR (optional,
not available in DGP***ABA models) can be set from 0.5 to 99.9 W each.
The reverse power levels (REV PWR) of 32-1 and 32-2 should be set at 30 to 70% (depending on power factor
following the turbine trip) of the turbine-generator motoring power .
Integrating type timers are associated with anti-motoring to achieve high level of dependability when the power
is around the REV PWR setting, particularly at high power factor. If Setting 803: SQ TR EN (sequential trip
enable) is set to YES, a value of three seconds or less is suggested for the timer TL1 associated with 32-1. If
SQ TR EN is set to NO, Setting 805: TL1 should be identical to Setting 904: TL2 described below.
Timer TL2, associated with 32-2, should be set to override the power swings expected during normal system
operations. A setting of 10 to 60 seconds is suggested.
Setting 803: SQ TR EN can be set to YES or NO, depending on the generator tripping strategy used.
GE Power Management
X
C1
R1
40-1
R2
40-2
C1 = Center of 40-1
= (Zb + X'd)/2
R1 = Radius of 40-1
= Zb/2
C2 = Center of 40-2
= (Xd + X'd)/2
R2 = Radius of 40-2
= Xd/2
Zb = Base impedance of the machine
X'd = Transient reactance of the machine
Xd = Synchronous reactance of the machine
DGP Digital Generator Protection System
2.3 PROTECTION FUNCTION SETTINGS
X'd/2
Zb
Xd

2.3.6 ANTI-MOTORING (REVERSE POWER)

R
2
2-
21