Open-Winding Fault-Tolerant Three-Vector Current Control Based on Current Ripple Reduction

In order to further improve the operation performance of the common DC bus open-winding permanent magnet synchronous motor (OW-PMSM) system under a phase open-circuit fault, this paper designs a three-vector current model predictive control strategy for the single-phase open-circuit fault of the OW-PMSM. First, the mathematical model under phase loss in the open-winding configuration is analyzed, and a new dq-axis decoupled voltage equation is provided. Then, within a single sampling period, the predicted current values of the 6 valid voltage vectors are calculated and sequentially substituted into the cost function. The voltage vector corresponding to the predicted current value that minimizes the cost function is selected as the first optimal voltage vector. Next, the current error vector's sector is determined, and the second optimal vector is chosen based on the angle comparison. Finally, the zero vector is added to adjust the amplitude. This method can cover any direction and any amplitude, and simultaneously achieves deadbeat control for the dq-axis currents. Experimental results demonstrate the feasibility and effectiveness of the proposed method.