Predictive direct torque control for permanent-magnet synchronous machines based on duty ratio modulation

In this paper, Two-step model predictive control based on duty ratio modulation of permanent magnet synchronous machine (PMSM) is proposed. There is a large amount of computation in the two-step predictive control. In this paper, a fast vector selection method is proposed to solve the problem of computational complexity. The proposed voltage vector selection method avoids the complete enumeration for testing all feasible voltage vector, and the calculation method of duty are discussed. This control method achieves a constant switching frequency, and the torque fluctuation is smaller, inheriting the advantages of predictive control response speed. To investigate the effectiveness of the proposed method, two-step predictive direct torque control based on duty ratio modulation (TSPTC-DM), comparison of one-step predictive direct torque control based on duty ratio modulation (OSPTC-DM) and finite control set model predictive torque control (FCS-MPTC) is shown. (paper)