Abstract: It is very important to obtain the rotor position in the permanent magnet synchronous motor drive system, which affects the safety and stability of the system. Its position sensor often fails due to the poor working environment, mismatches between signals and other reasons, which can not provide effective rotor position information for the drive control system. Based on the control method of direct torque control, this paper constructs a sliding film observer based on the back electromotive force, which is used for the fault diagnosis of surface-mounted permanent magnet synchronous motor. The sliding mode observer is constructed by reasonable sliding film gain value and switching function, the rotor position information is extracted by arctangent function, and the simulation model is built in MATLAB/Simulink for verification.

Key words: Surface permanent magnet synchronous motor; Back electromotive force; Rotor position estimation; Fault diagnosis

摘要： 永磁同步电机驱动系统中转子位置的获取至关重要，影响着系统运行安全与稳定性。 其位置传感器常常因为工作环境较为恶劣，信号间的不匹配等原因产生故障，无法为驱动控 制系统提供有效的转子位置信息。文章基于直接转矩控制的控制方法，构建了一种基于反电 动势的滑膜观测器，用做表贴式永磁同步电机故障诊断。通过合理的滑膜增益值与切换函数 构建滑模观测器，通过反正切函数提取转子位置信息，并在 MATLAB/Simulink 中搭建仿真模 型进行验证。

关键词: 表贴式永磁同步电机；反电动势；转子位置估计；故障诊断