Research on five-phase flux-intensifying permanent magnet motor drive system based on new active sensorless strategy

For the sensorless control system of the five-phase interior permanent magnet (IPM) motors, its saturation effect greatly affects the estimated accuracy of rotor position, which will not meet the requirement of multi-operating conditions for electric vehicles (EVs). To solve the saturation effect problem, a new active sensorless control strategy is proposed from the perspective of the motor drive system. Based on the analysis of the influence of the saturation effect on the rotor position observation, a five-phase flux-intensifying fault-tolerant interior permanent magnet (FIFT-IPM) motor is proposed with the enhanced reverse saliency effect. Thus, the cross-coupling and parameter variation caused by the saturation effect can be suppressed. Furthermore, from the perspective of the control algorithm, a secondary harmonic suppression method based on adaptive-band filtering (ABF) is proposed to further improve the dynamic and steady-state performance of the five-phase FIFT-IPM motor drive system without position sensor control. Finally, the correctness and effectiveness of the proposed strategy is verified by experimental results.