Description

This model is based on the IEEEX1 excitation system model [1]. It includes transducer, transient filter, voltage regulator, exciter, and damping feedback models to maintain voltage stability under varying conditions, essential for power system stability studies.

Mask and Parameters

Exciter Parameters

Se(Efd) uses a piece-wise linear function to compute the feedback gain:

Name	Description	Unit
Tr	Transducer time constant (lag)	s
Tb	Transient filter time constant (lag)	s
Tc	Transient filter time constant (lead)	s
Ka	Voltage regulator gain	-
Ta	Regulator time constant (lag)	s
Vrmax	Maximum voltage regulator output	pu
Vrmin	Minimum voltage regulator output	pu
Te	Exciter time constant (lag)	s
Ke	Linear gain of exciter feedback	-
Efd1	Field voltage at the first breakpoint	pu
Se1	Gain at the first breakpoint	-
Efd2	Field voltage at the second breakpoint	pu
Se2	Gain at the second breakpoint	-
Kf	Excitation control system stabilizer gain	-
Tf	Excitation control system stabilizer time constant (lag)	s

Initial Values

Efd0 can be manually set by entering a numerical value. It can be set as "=SM1.EFD_Init" if a pu standard or pu fundamental machine is used.

Name	Description	Unit
Efd0	Exciter output voltage initial value	pu

Inputs, Outputs and Signals Available for Monitoring

Inputs

Name	Description	Unit

Name	Description	Unit
E_C	Output of terminal voltage transducer and load compensation elements	pu
V_UEL	Underexcitation limiter output	pu
V_OEL	Overexcitation limiter output	pu
V_othsg	Stabilizer output	pu
V_REF	Voltage regulator reference voltage	pu

Outputs

Name	Description	Unit

Name	Description	Unit
EFD	Exciter output voltage	pu

Reference

[1] Computer representation of excitation systems, IEEE Transactions on Power Apparatus and Systems ( Volume: PAS-87, Issue: 6, June 1968)