Research of sensorless control for multiphase induction motor based on high frequency injection signal technique

This paper introduces multiphase induction motor drives system under sensorless conditions, which is simulated and analyzed by utilizing its multiple control freedoms in the mode of high frequency signal injection. In this method, because nine phase induction motor have four orthogonal d-q planes compared to traditional three phase induction motor, so high harmonic plane can be used for other applications, for example, extracting rotor position based on high frequency injection signal technique. In the multiphase induction motor, inductance value is smaller in the high harmonic plane contrast to fundamental plane, in other words, it can get larger current signal amplitude under the same voltage amplitude, reducing the difficulty of the position signal extraction. changing rotor slot numbers will affect the air-gap length distribution, and it can be concluded that there is a saliency in the d₇-q₇ plane through modulation of rotor slots. The module is simulated in the environment of simulink and ansoft.