A new separate-identification method of two stator equivalent core-loss resistances corresponding to hysteresis and eddy-current losses for Parallel-type mathematical models of AC motors

This paper proposes a new unified method for identifying equivalent stator core-loss resistance of AC motors, which can be Applied to both induction and synchronous motors. In order to realize AC motors that exhibit high performance such as precise torque generation and/or efficient energy transmission, stator core loss cannot be neglected in designing vector control systems. It is common to model stator core loss in magnetic circuits as loss caused by equivalent resistance in electrical circuit. One of the best mathematical models for controlling AC motors with core loss is a kind of parallel-type model that succeeds in modeling both eddy-current and hysteresis losses. The newly proposed method succeeds in identifying separately and simultaneously two kinds of equivalent core-loss resistances on the model corresponding to eddy-current and hysteresis losses. The practical usefulness of the method is evaluated and confirmed through experiments using two induction motors of 5.5 and 2.0 kW having relatively high core losses and a permanent magnet synchronous motor of 750 W having relatively low core losses. (C) 2003 Wiley Periodicals, Inc.