Electronic Pole-Changing Strategy with Cosine-Response for Multiphase Induction Motor Based on PR Controller

The multiphase induction motor (MIM) suffers the problems of unsmoothness and slow dynamic response during the process of electronic pole-changing. To solve this issue, a cosine-response strategy based on proportional resonance (PR) current controller is proposed. Firstly, a current switching strategy with cosine-response is designed, which makes the MIM work more smoothly while switching between two planes. Then, the PR controller based on static coordinate system is adopted to replace the traditional proportional integral current loop controller, which realizes the zero steady-state error tracking of the current and improves MIM's dynamic response. Experiments on a five-phase induction motor verify that the proposed strategy can reduce the fluctuations of the torque, speed, and total harmonic distortion of phase current. Besides, it can improve the dynamic response of the torque and speed when the pole-changing is switched.