Predictive Torque Control for Open-End Winding PMSM With Common DC Bus Based on Weighting Factorless and Finite Control Set Optimization

Abstract

The conventional predictive torque control (PTC) for three-phase open-end winding permanent magnet synchronous motor (OEW-PMSM) has the following disadvantages: tedious tuning of weighting factors, large ripples of zero-sequence current, electromagnetic torque, and stator flux. To overcome the above problems, a PTC based on weighting factorless and finite control set (FCS) optimization is proposed in this article. First, a deadbeat control strategy is proposed to convert the control of zero-sequence current, electromagnetic torque, and stator flux into the control of stator voltage vector. Since the equivalent control objects have the same unit, the weighting factors are not required. Second, a two-step optimization scheme for FCS is proposed to reduce the ripples of zero-sequence current, electromagnetic torque, and stator flux. Finally, an optimized pulsewidth modulation (PWM) strategy, which can help to reduce the switching frequency, is proposed. The feasibility and effectiveness of the proposed PTC strategy is verified by experiments on a 1-kW OEW-PMSM.