ECE 576 POWER SYSTEM DYNAMICS AND STABILITY Lecture 5 Synchronous Machine Dynamics Professor Pete Sauer Department of Electrical and Computer Engineering © 2000 University of Illinois Board of Trustees, All Rights Reserved

Change from “motor” to “generator” notation. Per unit variables and parameters (scaling) Change from “motor” to “generator” notation. Modify the flux linkage current relationship to account for the non power invariant “dqo” transformation.

where VBABC is rated RMS line-to-neutral stator voltage and

where VBDQ is rated peak line-to-neutral stator voltage and

where the rotor circuit base voltages are and the rotor circuit base flux linkages are

Assume sinusoidal steady state

These algebraic equations can be written as complex equations, Using These algebraic equations can be written as complex equations,

Now assume a linear magnetic circuit

L12 = 0 L12 = + maximum L12 = - maximum

Recall the reciprocity conditions Etc.

Define new variables

Substitute new variables and solve for rotor currents

Final complete model

Nonlinear magnetic circuits