Excitation System Models

Simple Excitation System

Figure 1: Simple Exciter Model Block Diagram

Figure 2: IEEE Type 1 Model Block Diagram

Parameter	Units	Description
T_R	Seconds	Transducer time constant
T_A	Seconds	AVR time constant
T_E	Seconds	Exciter time constant
T_F	Seconds	Field voltage feedback time constant
K_A	pu	AVR gain
K_E	pu	Exciter K_E
K_F	pu	Field voltage feedback gain
V_{R Max}	pu	AVR limit max
V_{R Min}	pu	AVR limit min
E₁	pu	Saturation voltage point 1
E₂	pu	Saturation voltage point 2
S( E₁ )	pu	Saturation at E₁
S( E₂ )	pu	Saturation at E₂

Figure 3: IEEE Type 2 Model Block Diagram

Parameter	Units	Description
T_R	Seconds	Transducer time constant
T_A	Seconds	AVR time constant
T_E	Seconds	Exciter time constant
T_F1	Seconds	Field voltage feedback time constant 1
T_F2	Seconds	Field voltage feedback time constant 2
K_A	pu	AVR gain
K_E	pu	Exciter K_E
K_F	pu	Field voltage feedback gain
V_{R Max}	pu	AVR limit max
V_{R Min}	pu	AVR limit min
E₁	pu	Saturation voltage point 1
E₂	pu	Saturation voltage point 2
S( E₁ )	pu	Saturation at E₁
S( E₂ )	pu	Saturation at E₂

Figure 4: IEEE Type AC1A Model Block Diagram

Parameter	Units	Description
T_R	Seconds	Sensor time constant
T_A	Seconds	Main AVR time constant
T_B	Seconds	Second block AVR lag time constant
T_C	Seconds	Second block AVR lead time constant
T_E	Seconds	Exciter time constant
T_F	Seconds	Feedback lag time constant
K_A	pu	First block main AVR gain
K_C	pu	Exciter K_C – Field current feedback
K_D	pu	Exciter K_D – Field current feedback
K_E	pu	Exciter K_E
K_F	pu	Feedback gain
V_AMax	pu	AVR control max
V_AMin	pu	AVR control min
V_RMax	pu	Regulator max - Amplifier
V_RMin	pu	Regulator min - Amplifier
E₁	pu	Saturation voltage point 1
E₂	pu	Saturation voltage point 2
S(E₁)	pu	Saturation at E₁
S(E₂)	pu	Saturation at E₂
V_UEL	pu	Fixed Under Excitation Limit
V_OEL	pu	Fixed Over Excitation Limit

Figure 5: IEEE Type AC6A Model Block Diagram

Parameter	Units	Description
T_R	Seconds	Sensor time constant
T_K	Seconds	First block lead time constant
T_A	Seconds	First block lag time constant
T_B	Seconds	Second block lag time constant
T_C	Seconds	Second block lead time constant
T_E	Seconds	Exciter time constant
T_J	Seconds	Feedback lead time constant
T_H	Seconds	Feedback lag time constant
K_A	pu	First block gain
K_C	pu	Exciter K_C – Field current feedback
K_D	pu	Exciter K_D – Field current feedback
K_E	pu	Exciter K_E
K_H	pu	Feedback gain
V_FELim	pu	V_FE limit value
V_HMax	pu	Feedback max
V_AMax	pu	AVR control max
V_AMin	pu	AVR control min
V_RMax	pu	Regulator max - Amplifier
V_RMin	pu	Regulator min - Amplifier
E₁	pu	Saturation voltage point 1
E₂	pu	Saturation voltage point 2
S(E₁)	pu	Saturation at E₁
S(E₂)	pu	Saturation at E₂

Figure 6: IEEE Type AC8B Model Block Diagram

Parameter	Units	Description
T_R	Seconds	Transducer time constant
T_A	Seconds	Main AVR time constant
T_E	Seconds	Exciter time constant
T_DR	Seconds	Differential time constant for PID control
K_PR	pu	Proportional gain for PID control
K_IR	pu	Integral gain for PID control
K_DR	pu	Differential gain for PID control
K_A	pu	Main AVR time constant
K_C	pu	Exciter K_C – Field current feedback
K_D	pu	Exciter K_D – Field current feedback
K_E	pu	Exciter K_E
V_{R Max}	pu	Regulator max - Amplifier
V_{R Min}	pu	Regulator min - Amplifier
V_{E Max}	pu	Exciter max
V_{E Min}	pu	Exciter min
E₁	pu	Saturation voltage point 1
E₂	pu	Saturation voltage point 2
S(E₁)	pu	Saturation at E₁
S(E₂)	pu	Saturation at E₂

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Dynamic Stability
Stability Data Parameters