Theory and Comparison of Reduced Order Models of Induction Machines

Three methods of deriving linearized, reduced order models of induction machines are presented and compared. The first is the familiar method of neglecting stator transients (p¿terms). Although the development of the second method is similar to the first, it yields a model with substantially different dynamic characteristics. In the third method, only the fast components of the stator flux linkages are neglected in the solution of the slower rotor variables rather than neglecting the rate of change of stator flux linkages (p¿terms). This refinement markedly improves the accuracy of the resulting reduced order model. The improvement is demonstrated by comparison of the response characteristics predicted by the three reduced models with that predicted by the complete or detailed model.