Model Predictive Direct Duty-Cycle Control for PMSM Drive Systems With Variable Control Set

Abstract

Finite control set model predictive control has received extensive attention because of its excellent dynamic performance; however, it still needs to be studied in terms of torque ripples reduction and parameter robustness. To reduce the steady-state torque ripples and maintain the appropriate antiparameter perturbation ability, in this article, we propose a model predictive direct duty-cycle control (MPD2C) strategy based on “variable control set (VCS).” In the proposed strategy, the direct mapping relations between the electromagnetic torque, flux, and three-phase duty cycles have been established by exploring the dual relationship of vector synthesis and duty cycles. On this basis, the novel predictive model and VCS that uses the three-phase duty cycles as the key variable are constructed. Finally, the proposed strategy determines the three-phase duty cycles from VCS by employing a two-stage optimization mechanism, which means the proposed strategy can generate virtual vectors with multiple insulated gate bipolar transistor (IGBT) switching patterns. Then, the high-precision torque and flux adjustment would be achieved. The experimental results show that VCS-MPD2C has excellent static and dynamic control performance, acceptable execution efficiency, and relatively good parameter robustness.