Improved Deadbeat Predictive Current Control for SPMSM based on Multi-Step Prediction

In this paper, a multi-step accurate deadbeat predictive current control (MADPCC) algorithm is proposed to improve the current loop’s dynamic performance of the surface-mounted permanent magnet synchronous motor (SPMSM). Under high speed and heavy load conditions, the motor’s back electromotive force is large and the actual output voltage is limited, which cannot provide sufficient current change rates. Therefore, the traditional single-step prediction algorithm is difficult to achieve the optimal transient process because the current cannot reach its reference value in one control cycle and the variation of the voltage vector’s angle is also neglected during the prediction process. To solve this problem, the proposed MADPCC method first establishes an accurate discrete model of the SPMSM, and estimates the control step length required to reach the given reference current through a simple algorithm. Then the single-step prediction is extended to multi-step prediction. Simulation results show that the dynamic performance of MADPCC is improved compared with the single-step DPCC method.