Exciter Model: AC8C

 

Following checks and corrections are applied during Validation and AutoCorrection.

  • If 0 < Te < Mult*TimeStep then Te = Mult*TimeStep
  • If 0.0 < Ta < 0.5*Mult*TimeStep then Ta = 0, ElseIf 0.5*Mult*TimeStep < Ta < Mult*TimeStep then Ta = Mult*TimeStep
  • If 0.0 < Tdr < 0.5*Mult*TimeStep then Tdr = 0, ElseIf 0.5*Mult*TimeStep < Tdr < Mult*TimeStep then Tdr = Mult*TimeStep
  • If 0.0 < Tr < 0.25*Mult*TimeStep then Tr = 0.0

    ElseIf 0.25*Mult*TimeStep < Tr < 0.5*Mult*TimeStep then Tr = 0.5*Mult*TimeStep
  • If Vrmax < Vrmin then swap the values
  • If Vpidmax < Vpidmin then swap the values

Mult represents the user-specified value Minimum time constant size as multiple of time step option on the Validation page of the Transient Stability Dialog

TimeStep represents the integration time step being used as described on TimeStep

Following treatment is handled during the transient numerical simulation

  • If Vr > Vrmax, then Vrmax = Vr limits or if Vr < Vrmin, then Vrmin = Vr

Model Equations and/or Block Diagrams

Parameters:

OEL OEL input: if < 2, add to error signal; if = 2, LV gate 1; if = 3, LV gate 2
UEL UEL input: if < 2, add to error signal; if = 2, HV gate 1; if = 3, HV gate 2
SCL SCL input: if < 2, add to error signal; if = 2, LV gate 1; if = 3, LV gate 2
VOS PSS input: if = 1, add to error signal; if = 2, add after HV gate 1
SW1 Logical switch 1 (1 = Position A, 2 = Position B)
Tr Filter time constant, sec
Kpr Proportional gain, pu
Kir Integral gain, pu
Kdr Regulator derivative gain, pu
Tdr Derivative gain washout time constant, sec
Vpidmax PID maximum limit
Vpidmin PID minimum limit
Ka Voltage regulator gain
Ta Voltage regulator time constant, sec
Vrmax Maximum exciter control signal, pu
Vrmin Minimum exciter control signal, pu
KC Rectifier loading factor proportional to commutating reactance
Kd Exciter internal reactance, pu
Ke Exciter field resistance constant, pu
Te Exciter field time constant, sec
Vfemax Exciter field current limit parameter, pu
Vemin Minimimum exciter output voltage, pu
E1 Field voltage value, 1
SE1 Saturation factor at E1
E2 Field voltage value, 2
SE2 Saturation factor at E2
Kp Potential source gain, pu
Ki Potential circuit (current) gain coefficient
XL Reactance associated with potential source
ThetaP Potencial circuit phase angle, degrees
KC1 Rectifier loading factor proportional to commutating reactance
Vbmax Maximum available exciter field voltage
Spdmlt If not zero, multiply output (Efd) by generator speed