Exciter Model: AC2C
Following checks and corrections are applied during Validation and AutoCorrection.
- If 0 < Te < Mult*TimeStep then Te = Mult*TimeStep
- If 0 < Tf < Mult*TimeStep then Tf = 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 < Tb < 0.5*Mult*TimeStep then Tb = 0, ElseIf 0.5*Mult*TimeStep < Tb < Mult*TimeStep then Tb = 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 Ka = 0 then Ka = Mult*TimeStep
- If Kb = 0 then Kb = Mult*TimeStep
- If EFEmax < EFEmin then swap the values
- If Vamax < Vamin 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 Va > Vamax, then Vamax = Va limits or if Va< Vamin, then Vamin = Va
- If EFE > EFEmax, then EFEmax = EFE limits or if EFE limits < EFEmin, then EFEmin = EFE limits
Model Equations and/or Block Diagrams
Parameters:
| OEL | OEL input: if = 2, LV gate; if < 2, subtract from error signal |
| UEL | UEL input: if = 2, HV gate; if < 2, add to error signal |
| SCL | SCL input: if = 2, LV gate; if < 2, subtract from error signal |
| Tr | Filter time constant, sec |
| Tb | Time constant, sec |
| Tc | Time constant, sec |
| Ka | Voltage regulator gain |
| Ta | Voltage regulator time constant, sec |
| VaMax | Maximum control element output, pu |
| VaMin | Minimum control element output, pu |
| Kb | Exciter field current controller gain, pu |
| Eefmax | Maximum exciter field voltage, pi |
| Eefmin | Minimum exciter field voltage, pi |
| Te | Exciter field time constant, sec |
| Vfemax | Exciter field current limit parameter, pu |
| Kh | Exciter field current feedback gain, pu |
| Kf | Rate feedback gain, pu |
| Tf | Rate feedback constant, sec |
| Kc | Rectifier loading factor proportional to commutating reactance |
| Kd | Exciter internal reactance, pu |
| Ke | Exciter field resistance constant, pu |
| E1 | Field voltage value, 1 |
| SE1 | Saturation factor at E1 |
| E2 | Field voltage value, 2 |
| SE2 | Saturation factor at E2 |
| Vemin | Minimimum exciter output voltage, pu |
| Spdmlt | If not zero, multiply output (Efd) by generator speed |