Smooth switching mechanism-based adaptive integral terminal SMC for PMSM servo system with stator voltage saturation and unknown disturbances

关键词:  Smooth switching mechanism · Integral terminal SMC · PMSM servo system · Disturbance suppression · Stator voltage saturation

Key words:  Smooth switching mechanism · Integral terminal SMC · PMSM servo system · Disturbance suppression · Stator voltage saturation

摘要:

This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor (PMSM) with stator voltage saturation and unknown load. A smooth switching mechanism is presented to structure the adaptive integral terminal sliding mode control (SMC) strategy. The control design consists of compensation control and nominal control, which improves the rapidity and accuracy of trajectory tracking. The smooth saturation model based on the error function is applied to approximate the voltage saturation phenomenon. Additionally, to deal with the adverse effects of various unknown disturbances, including model parameter uncertainties and unknown external load disturbances, an improved disturbance observer (DO) is proposed. This observer effectively suppresses the fluctuations caused by fixed gain during the starting period of the system. Finally, the experimental results under different conditions show that the proposed strategy has good tracking and disturbance suppression performances.

Abstract:

This article investigates the anti-disturbance and stabilization problems for the nonlinear uncertain permanent magnet synchronous motor (PMSM) with stator voltage saturation and unknown load. A smooth switching mechanism is presented to structure the adaptive integral terminal sliding mode control (SMC) strategy. The control design consists of compensation control and nominal control, which improves the rapidity and accuracy of trajectory tracking. The smooth saturation model based on the error function is applied to approximate the voltage saturation phenomenon. Additionally, to deal with the adverse effects of various unknown disturbances, including model parameter uncertainties and unknown external load disturbances, an improved disturbance observer (DO) is proposed. This observer effectively suppresses the fluctuations caused by fixed gain during the starting period of the system. Finally, the experimental results under different conditions show that the proposed strategy has good tracking and disturbance suppression performances.