永磁同步电机扩展滑模观测器设计

Design of Extend Solid-Mode Observer for Position Sensorless PMSM

为了提高永磁同步电机无位置传感器控制系统的转子位置估算精度,研究一种以反电动势信息作为扩展变量的扩展滑模观测器(ESMO)。根据李雅普诺夫稳定性定理设计了一种简化的滑模系数的设计方法,并着重分析了系统的抖振现象与反馈增益之间的关系。不同于传统的滑模观测器,本文采用一种新型的切换函数,通过合理的设计切换函数的参数,可以有效的减少稳态误差和抑制抖振现象。最后利用软件锁相环结构来提取电机位置信息和转速。经仿真验证,设计的观测器能够获得满意的跟踪性能。

An extended sliding mode observer（ ESMO） is proposed to improve the precision of the rotor position estimation,where back electromotive force is selected as extended variable. According to Lyapunov principle,a simplified sliding coefficient designing method was presented,the correlation between chattering and sliding mode gain was especially analyzed. Different from traditional sliding mode observer,the alternative switching function was introduced and the reasonable parameter was adjusted to reduce the steady-state error and avoid steady-state high frequency flutter simultaneously. Finally,the soft phase lock is employed to calculate rotor position and speed. Simulations show that the proposed observer can achieve satisfactory track performance.