Analysis of magnetic saturation in induction motor drives

The purpose of this paper is to provide a numerical method for identification of the mutual inductance and leakage inductances of an induction motor operating either in open-loop or closed-loop drives. This paper presents a numerical method for computing steady-state and dynamic performances of a saturated induction motor. Input parameters of this method are unsaturated inductances and corresponding saturation curves. Computation of steady-state performance is based on an iterative numerical procedure. Computing dynamic states assumes that leakage inductance and mutual inductance depend on the values of the motor currents. This paper also presents a conventional indirect rotor field oriented (RFO) control system, where mutual inductance is identified in two ways. The first way identifies the mutual inductance depending on the rotor flux reference. The second way identifies the mutual inductance upon the value of the magnetizing current. These results ensure utilization of the indirect RFO control system at variable magnetizing levels. A comparison of these two methods is presented The effectiveness of the proposed method is verified through simulation and experimentation. Copyright (c) 2008 Praise Worthy Prize S.r.l - All rights reserved.