永磁同步电机抗扰高阶滑模观测器设计

Design of Robust High Order Sliding Mode Observer for Permanent Magnet Synchronous Motors

永磁同步电机高精度矢量控制需要准确的电机转速与转子位置信息。考虑到传统观测器中的参数摄动和抖振现象,在保持算法简单、易实现的基础上,将一种基于高阶滑模的超螺旋方法引入到永磁电机观测器的设计中。通过非线性方法证明了电机在一定条件下的可观测性,充分考虑实际系统中参数变化的影响,在静止两相坐标系上建立相应的数学模型,设计超螺旋算法观测电机反电动势值,并采用软件锁相环结构估算电机的速度。理论上验证了该算法的稳定性和有限时间收敛性。实验结果表明,所提出的观测器具有良好的跟踪性能,对电机参数摄动有很强的鲁棒性。

High precision vector control of permanent magnet synchronous motor drive requires accurate motor speed and rotor position. Taking chattering and parameter perturbations in conventional sliding mode observer and easy realization into consideration, a novel high-order sliding mode observer by using super twisting algorithm(STA) is proposed. Observability of PMSM under certain conditions is proved by the nonlinear method. Considering the impact of changes in the actual system parameters, corresponding mathematical model in stationary two-phase coordinate is established. Based on above model, STA control scheme is formulated to estimate back electromotive force of PMSM and software phase lock loop is designed to estimate the rotor speed. In theory, the stability and finite time convergence performance of STA are verified. Experimental results show that the novel strategy has good tracking performance and strong robustness to parameter perturbation.