带负载转矩估算的非线性观测器内嵌式永磁同步电机无位置传感器控制策略

Nonlinear Observer With Load-Torque Estimation for Sensorless Control Strategy of Interior Permanent Magnet Synchronous Motor

针对内嵌式永磁同步电机无位置传感器控制系统中转子位置和转速估算精度不高的问题,提出一种带有负载转矩估算的非线性观测器方法。基于合成反电动势建立了内嵌式永磁同步电机的数学模型,在静止坐标系下设计了非线性观测器,通过状态矫正控制策略,使非线性观测器收敛到期望的平衡点。依据扰动理论建立了负载转矩估算方程,在线估算负载转矩,以消除由机械模型误差引起的转子位置和转速的估算误差。在无位置传感器控制实验平台上进行了实验验证,实验结果表明所提出的方法能够在稳态和动态条件下准确估算转子位置和转速。

For the estimated rotor position and speed were inaccurate in sensorless interior permanent magnet synchronous motor（IPMSM） control system, a nonlinear observer method with load torque estimation was proposed. Mathematical model for IPMSM was built based on synthetic back EMF, and the nonlinear observer was designed in stator-fixed coordinate frame. Then, a state-adjust strategy had been supplemented to force the nonlinear observer to converge to the expected equilibrium point. Based on the disturbance theory, load torque estimating equation was designed, and by on-line estimating for the load torque, estimation errors in rotor position and speed induced by mechanical model uncertainty was eliminated. Experimental tests implemented on the testing platform for sensorless control had demonstrated that accurate estimation for rotor position and speed during steady-state and transient period can be obtained with the proposed method.