Quick and stable speed control of SPMSM based on current differential signal for voltage saturation region

In AC servo system, the output voltage is restricted by inverter output limitations. Voltage saturation occurs as a result of this limitation. The settling time of current and speed increases because of voltage saturation. This paper proposes a new control system for improving the transient response of surface permanent magnet synchronous motor (SPMSM) by using the proposed flux-weakening control based on current differential signal. As a result of considering the current differential signal, the suppression of voltage saturation is realized with optimal d-axis current in a transient state. The proposed speed control system realizes the quick and stable speed and current response. The effectiveness of proposed control method is confirmed by the numerical simulation results and the experimental results.