Minimum-copper-loss Operation of an IPM Synchronous Machine for HEV/FCV Applications

This paper presents an algorithm to control an interior permanent-magnet synchronous machine in minimum- copper-loss operation for hybrid electric vehicle/fuel cell vehicles. The d- and q-axis current references in the rotor reference frame are generated from each two-dimensional look-up table whose inputs are torque command and inversed flux magnitude. The effect of a stator resistance on the voltage limit condition depending on motoring/regenerating operation is taken into account when the inverse flux magnitude is calculated to generate current references. Considering magnetic saturation, this work also describes how to obtain two more look-up tables whose inputs are each axis current and whose outputs are the corresponding axis flux linkage, respectively. An averaged simulation model for the drive system takes advantage of simpowersystems for Simulinkreg. Simulation and test results show characteristics of the proposed method.