Exciter Model: EXAC4
Following checks and corrections are applied during Validation and AutoCorrection.
- If 0.0 < Tr < 0.5*Mult*TimeStep then Tr = 0, ElseIf 0.5*Mult*TimeStep < Tr < Mult*TimeStep then Tr = Mult*TimeStep
- If 0.0 < Tb < 0.5*Mult*TimeStep then Tb = 0, ElseIf 0.5*Mult*TimeStep < Tb < Mult*TimeStep then Tb = Mult*TimeStep
- If 0 < Ta < Mult*TimeStep then Ta = Mult*TimeStep
- If Vrmax < Vrmin then swap the values
- If Vimax < Vimin 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 Vi > Vimax, then Vimax = Vi or if Vi < Vimin, then Vimin = Vi
Model Equations and/or Block Diagrams
Parameters:
| Tr | Filter time constant, sec |
| ViMax | Maximum error, pu |
| ViMin | Minimum error, pu |
| Tc | Time constant, sec |
| Tb | Time constant, sec |
| 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 |