A novel deadbeat predictive current control of permanent magnet synchronous motor based on oversampling scheme

Abstract

AbstractWhen the speed of permanent magnet motor is relatively high, the fundamental frequency of stator voltage and current will rise. However, due to the limitation of switching frequency of power electronic devices, the switching times of power devices will be greatly reduced in a fundamental cycle of stator voltage. For the traditional control method with constant switching frequency mode, the control algorithm is executed only once in a carrier wave cycle, which will result in a low control frequency operating condition for the PMSM control system. At this time, the dynamic and steady‐state control performance of stator current will be decreased. In response to above problem, this paper proposed a deadbeat predictive current control method based on oversampling scheme, which the core algorithm of current loop operated four times and updated the PWM duty twice in one switching cycle. The number of control times of the proposed method is greater than that of the conventional method when the conventional deadbeat method and the proposed method adopt the same switching cycle. Therefore, the control method does not increase the switching frequency of power devices, but improves the dynamic and stable performance of the system, especially under the high‐speed condition.