Loss-Optimization Method of Permanent-Magnet Synchronous Motor Based on Precise Stator Iron Loss Model
Haitao Zhang, Manfeng Dou, Changliang Dang
Abstract
Traditional stator iron loss models lack precision when they are used for loss optimization of permanent-magnet synchronous motor (PMSM), because nonuniform distribution and nonsinusoidal waveform of the flux density in stator core are not fully considered. In this article, a new model is developed with a higher precision, in which the nonuniform flux density in stator core is observed through two virtual coils wounded on the yoke and tooth of a finite element model. Then, the stator iron loss is calculated depending on induced voltages of the coils. Moreover, nonsinusoidal waveform of the flux density is considered in the development. Based on this model, a loss-optimization method is proposed, in which the optimal current reference is determined by minimizing the stator loss under a constraint of ripple-free torque. Limitations of DC voltage supply and current amplitude are also considered to improve robustness of the method. Finally, precision of the iron loss model and performance of the loss-optimization method are validated experimentally on a 3.8-kW PMSM setup.