Simple Rotor Polarity Reversal Recovery in EV Traction Motor Sensorless Control

This paper presents a simple method to detect and recover rotor polarity reversal in sensorless traction motor control for electric vehicles (EVs). This rotor polarity reversal may happen during the sensorless control due to severe noise in the controller or the change in rotor position faster than bandwidth for position estimation. Although it can lead to the dangerous accident because torque is generated in the unintended direction, previous studies have lacked effective solutions to address this issue in real-time. The proposed method offers its prompt and reliable solution at any operating speed of traction motor. In addition, it is easy to implement and computationally efficient, making it suitable for accident prevention of EVs. Results from simulation and hardware-in-the-loop tests demonstrate the effectiveness of proposed method in recovering polarity reversal and improving the safety of EVs.