关键词: 滑模控制, 不匹配负载扰动, 转矩脉动观测器, 降噪滤波, 三点取样法, 分离提取, 前馈补偿

Abstract: When the servo drive system contains umcertainties and mismatch load disturbances, conventional PI control and traditional sliding mode control(SMC) cannot obtain better control performance, a novel torque ripple observer is proposed tolimit torque ripple of sliding mode control. The expression of sliding mode controller and the waveform of the load torque were analyzed under its control, and it was obtained that the characteristic of load torque was periodic pulsation. According to the torque equation and motion equation of the permanent magnet synchronous motor, the torque value estimated by utilizing the speed value and q-axis current value was filtered by noise reduction.According to the characteristics of the SMC torque ripple, the algorithm ofthree point sampling method was proposed to extract stable load torque from the noise reduced load torque and then, the load torque ripple was separated to generate the ripple compensation, which was utilized by feed-forward compensation of the servo system. The results of simulation and experiments demonstrate that the novel torque ripple observer designed form the perspective of separation and extraction with the torque ripple tolimit load torque ripple is feasible.

Key words: sliding mode control(SMC), mismatch load disturbances, torque ripple observer, noise reduction filtering, three point sampling method, separation and extraction, feedforward compensation