Exciter Model: ST4C

Following checks and corrections are applied during Validation and AutoCorrection.

• 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 < Tr < 0.5*Mult*TimeStep then Tr = 0, ElseIf 0.5*Mult*TimeStep < Tr < Mult*TimeStep then Tr = Mult*TimeStep
• If 0.0 < Tg < 0.5*Mult*TimeStep then Tg = 0, ElseIf 0.5*Mult*TimeStep < Tg < Mult*TimeStep then Tg = Mult*TimeStep
• Kpm and Kim: Kpm can't be 0 if Kim = 0, if true then Kpm changed to 1.
• Kpr and Kir: Kpr can't be 0 if Kir = 0, if true then Kpr changed to 40.
• If Vrmax < Vrmin then swap the values
• If Vmmax < Vmmin 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 Vr > Vrmax, then Vrmax = Vr or if Vr < Vrmin, then Vrmin = Vr
• If Vm > Vmmax, then Vmmax = Vm or if Vm < Vmmin, then Vmmin = Vm
• If Va > Vamax, then Vamax = Va or if Va < Vamin, then Vamin = Va