Research on Short-Circuit of Fault-Tolerant Permanent Magnet Rim Driven Motor Based on SPSRF-MPCC Algorithm

The conventional double-vector model predictive current control based on rotating reference frame (RRF-MPCC) which used in fault-tolerant permanent magnet rim driven motor (FTPM-RDM) has the problems of large output torque ripple and long selection time of optimal voltage vector. Therefore, two novel MPCC algorithms based on six-phase stationary reference frame (SPSRF) without coordinate transformation are proposed in this paper to reduce torque ripple and computation burden. Both methods use the simplest computational steps to achieve the most effective control. The first method is the single-vector SPSRF-MPCC algorithm which groups alternative voltage vectors according to the magnitude of load torque. The second method is an improved double-vector combination optimal SPSRF-MPCC algorithm which makes two independent rounds of current prediction for each stator winding and goes through 61 space voltage vectors only 30 times compared with 122 times of conventional double-vector SPSRF-MPCC which also requires coordinate transformation. In addition, the fault-tolerant control of one-phase short-circuit is carried out with the current vector fault-tolerant control strategy. Finally, through the comparison and verification of simulation and experiment results, it is found that the double-vector SPSRF-MPCC algorithm can effectively reduce the torque ripple and current fluctuation, and it can improve the stability and robustness of the system.