ADRC-based Model Predictive Current Control for PMSMs fed by Three-phase Four-switch Inverters

A novel automatic disturbances rejection control (ADRC)-based model predictive current control (MPCC) strategy is developed for permanent magnet synchronous motors (PMSMs) fed by three-phase four-switch inverters, an after-fault-topology for fault-tolerant three-phase six-switch inverters. The mathematical model of a PMSM fed by a three-phase four-switch inverter is built firstly. Then the ADRC and MPCC are respectively designed, with the former being used to realize disturbance estimation and disturbance compensation while the latter being used to reduce stator current ripple and improve the quality of the torque and speed control. The resultant ADRC-based MPCC PMSM fed by an unhealthy inverter has fault-tolerant effective with dynamical performance very close to an ADRC-based MPCC PMSM fed by a healthy inverter. On the other hand, compared with PI-based MPCC PMSM fed by an unhealthy inverter, it possesses better dynamical response behavior and stronger robustness as well as smaller THD index of three-phase stator current in the presence of variation of load torque. The simulation results validate the feasibility and effectiveness of the proposed scheme.