Flux Weakening Control of Dual Five-Phase Hybrid Excitation Permanent Magnet Synchronous Motor

This article proposes a new flux-weakening (FW) control strategy for a dual five-phase hybrid excitation permanent magnet synchronous motor (DF-HEPMSM). The core innovation lies in achieving optimized FW current regulation through precise FW condition judgment. Because of its special dual-stator structure, the DF-HEPMSM has three FW regions: region I for main drive FW, region II for main drive excitation by auxiliary drive, and region III for main drive FW and excitation by auxiliary drive. By constructing the three FW regions, the speed range of motor operation is further enhanced precisely. Moreover, in order to achieve smoother region switching, the proposed strategy implements a torque threshold comparison mechanism, i.e., the output torque is compared to the critical torque to decide if entering FW control is necessary. This approach solves the issue of the traditional voltage feedback, which can easily enter a saturation or oversaturation state and cause system instability. Finally, the proposed control strategy is compared with the conventional voltage feedback FW control for the DF-HEPMSM. The experimental results demonstrate the effectiveness of the proposed method in terms of system response stability and speed range.