High Performance Sensorless Control Strategy of IPMSM Drives Based on High Frequency Square-Wave Voltage Injection

Abstract

In order to improve the dynamic performance of sensorless Interior Permanent Magnet Synchronous Motor (IPMSM) position observation at low speeds, this paper proposes a position error extraction method based on Luenberger observer and combined with deadbeat predictive current control (DPCC) strategy. To improve the robustness of the position observation, a high frequency square-wave voltage is injected into the d-axis to generate a high frequency current signal with position information. Then the actual current is subtracted from the observed signal to obtain the high frequency current error. The motor position information is calculated by position error decoupling and phase-locked loop. To improve the rapidity of the current loop, a DPCC strategy is adopted to obtain the predicted value of the motor current using the observer. Finally, the simulation results show that the proposed control method can reduce the overshoot of position observation error and the dynamic performance of the motor controller is improved.