Abstract: The 7-phase IM has drawn more attention because of its typical operation performance under open-phase fault recently. Under open-phase fault circumstance, it’s difficult to get the rigorous decomposition model and conventional SVPWM because of the asymmetrical structure and vector distribution. So a simple model is adopted including one d-q fundamental wave subspace and （5-n） harmonic wave subspaces. To get a round shape rotor flux and minimized harmonic component of stator currents, a new vector control strategy is proposed with modified UVM for 7-phase IM under open-phase fault. Besides double fuzzy PI controller is designed to get better dynamic performance of electromagnetic torque and less harmonic component of stator currents. Simulation results verify the correctness of the model and the superiority of the control strategy.

Key words: 7-phase induction motor, open phase, eliminate harmonic, vector control, fuzzy PI

摘要： 七相感应电机因缺相运行具有代表性而受到关注。在缺[n]相情况下，电压矢量幅值及分布不均匀，获取严格的空间解耦模型及常规SVPWM较为困难，故建立了[d-q]基波子空间+（5-n）个谐波子空间的缺相简化模型，通过追加令谐波子空间电压为零的约束条件，提出一种通用性较强的消除定子谐波电流的改进型UVM矢量控制方法，用以获得缺相后转子磁链为圆形同时定子电流谐波最小的控制效果。由于在所缺相数较多时，系统转矩动态响应及定子电流的谐波消除效果受到PI调节参数影响，又采用了双模糊PI控制器分别对转矩调节器和定子电流谐波调节器进行改进。仿真结果表明了缺相简化模型及控制算法的正确性和有效性。

关键词: 七相感应电机, 缺相故障, 消除谐波, 矢量控制, 模糊PI