Study of Reduced-order Models of Squirrel-cage Induction Motors

Abstract This article examines several reduced-order models of squirrel-cage induction motors. The full-order model and its reduced-order models are used to calculate motor speed behavior during symmetrical voltage sags. The stability predicted by several reduced-order models of induction motors during symmetrical voltage sags with different depths and durations is also explored. Moreover, simulations of 36 motors of different power ratings are performed, and results are compared with simulations made with the classical fifth-order single-cage model and its corresponding reduced-order models. The main conclusion is that for speed stability evaluation purposes, even the reduced first-order double-cage model gives better results than the fifth-order single-cage model, which neglects the deep-bar effect.