基于三相解耦SVPWM的六相游标永磁电机开相故障自然容错控制以降低转矩脉动

The multiphase vernier permanent magnet motor (VPMM) has attracted increasing attention due to its high torque density and superior fault-tolerant capability. In order to make full use of the fault-tolerant capability and avoid fault diagnosis errors or delays and the complexity of reconfiguration process, a three-phase decoupling space vector pulse width modulation (TPD-SVPWM) based natural fault-tolerant control (NFTC) is proposed to realize a smooth transition from healthy to fault-tolerant operation under open-phase faults for a symmetrical six-phase VPMM. Through the TPD-SVPWM technique, the voltage vectors of the six-phase voltage source inverter (VSI) are readily decomposed into ones of two three-phase VSIs to reduce the number of voltage vectors. Importantly, compared with the existing model predictive current control (MPCC) based NFTC, the deviation between actual output voltage vector and desired reference voltage vector is decreased due to adopting the SVPWM technique instead of the virtual vector selection of finite control set MPC, thereby conducive to the torque ripple suppression. The results show that the proposed TPD-SVPWM-based NFTC can provide satisfactory steady-state and dynamic performance, and make the torque ripple reduce from 22% to 10% compared with the MPCC-based NFTC.