Disturbance Rejection Control Method Based on Adaptive Composite Disturbance Observer for Permanent Magnet Synchronous Motor

The vehicle electronic scroll compressors exhibits significant speed fluctuations during low-speed and heavy-load operation. The periodic fluctuation of load torque leads to speed fluctuations. The limited sensitivity gain of traditional disturbance observers results in poor performance in suppressing periodic disturbances. In response to this issue, this study adopts an adaptive composite disturbance observer to estimate and compensate for load disturbances, in order to reduce speed fluctuations in the low-speed range. The adaptive composite disturbance observer has achieved simultaneous and adaptive observation and estimation of periodic and aperiodic slow varying disturbances. An adaptive notch filter (ANF) based on variable step-size quantize least mean square (VSQLMS) algorithm is used to estimate the fundamental frequency of periodic disturbances. Through simulation experiments, the method proposed has improved the control accuracy and dynamic response performance of the system, and has enhanced its robustness.