Adaptive flying start strategy for sensorless permanent magnet synchronous motor

Flying start is one of the key technologies in the control of position sensorless permanent magnet synchronous motor (PMSM) systems. The common method is to short-circuit the motor by triggering short-circuit pulses to achieve a flying start. In this paper, we propose an adaptive adjustment of the parameters of short-circuit pulse time and short-circuit pulse interval for the difficult selection of the parameters of the short-circuit pulse time and short-circuit pulse interval. The method estimates the approximate speed of the idling motor by adding a test short circuit under the idling condition. It adaptively adjusts the parameters of short-circuit pulse time and short-circuit pulse interval according to the above speed. The method solves the problem of low estimation accuracy due to the determination of parameters of the traditional two-short-circuit current method. It significantly improves the effectiveness of the two-short-circuit current method. Simulation and experimental validation of the above method are carried out, and the results show the correctness and effectiveness of the present method