Post-Fault Model Predictive Control Of Asymmetrical Six-Phase Permanent Magnet Machine With Improved Mathematical Model

Multiphase machines are superior to three-phase machines with high reliability and large power capability. In the post-fault operation when one phase of an induction machine is open circuit, model predictive control has been proved to have rapid current, torque and speed response. However, the mathematical model in post-fault operations of multiphase permanent magnet (PM) machines is quite different from induction machines and it has rarely been analyzed before, so it still needs further study. This paper looks deeply into the post-fault model of an asymmetrical six-phase PM machine and its drive system, and proposes an improved modeling method in which the phase voltages and inductance matrix are amended. Thus the concision of the prediction process can be maintained the same as in normal operations. Simulation results are given and proves the efficiency of the proposed method in both dynamic and steady states of post-fault operation.