Dynamic Performance Evaluation of a Nine-Phase Flux-Switching Permanent-Magnet Motor Drive With Model Predictive Control

Abstract

Multiphase flux-switching permanent-magnet (FSPM) motor drives are nowadays considered for various applications due to numerous advantages when compared with their three-phase counterparts. In principle, stator-flux-oriented control of a nine-phase flux-switching permanent-magnet (FSPM) (9P-FSPM) motor can be realized theoretically by using four pairs of synchronous current controllers in conjunction with eight conventional proportional-integrals (PIs), for alleviation of the coupling effects and unwanted low-order stator current harmonics. In practice, however, drive performance will deteriorate if the PI-based current controller is not well tuned for optimum response to every dynamic scenario due to nonlinearity. In order to enhance dynamic performance of the drive system, a fully-decoupled model predictive control algorithm with fixed switching frequency is developed for the 9P-FSPM motor. The main contribution is comprehensive and detailed description of precise modeling of the 9P-FSPM motor and the controller design process. Also, some practical hints are given for implementation, such as the elimination of low-order harmonic currents and the selection of active voltage vector in the nine-phase drive system. Both simulation and experimental results are presented to validate the effectiveness of the developed current controller and the high dynamic performance of the 9P-FSPM motor drive.