永磁同步电机滑模变结构转速直接观测器

A Direct Sliding Mode Speed Observer of PMSM

提出一种基于滑模变结构的永磁同步电机(PMSM)转速直接观测器(DSMSO),在直接转矩控制(DTC)系统中,利用观测器估算得到的转速实现电机无速度传感器控制。根据李亚普诺夫稳定性原理,推导出PMSM滑模观测模型的收敛条件,从而可直接估算出电机转速,去掉了转速间接观测器常用的低通滤波器和位置微分环节。仿真和实验结果表明,提出的DSMSO与现有转速间接观测器相比,在中高速和低速稳态运行情况下转速稳态观测精度有所提高,同时变速阶段的转速动态观测精度和误差收敛速度均有所提高。

A direct sliding mode speed observer （DSMSO） of permanent magnet synchronous motor（PMSM） is pre- sented.The estimated speed of DSMSO is used in a sensorless direct torque control（DTC） system.According to Lyapunov stability analysis, convergency condition of sliding mode observer is derived, from which the motor speed can be estimated directly without low pass filter and position differential used in indirect speed observer.Simulation and experimental results comfirm that, compared with indirect speed observer, steady accuracy of DSMSO at middle-high and low speed is improved as well as dynamic accuracy and convergency rate during acceleration and deceleration.