基于无传感器的PMSM电流控制策略的研究

Research on Sensorless PMSM Current Control Strategies

提出一种新型的滑模观测器,并分别研究在4种不同的电流控制策略下,基于该新型滑模观测器的PMSM伺服系统的控制问题。该新型滑模观测器引进了Sigmoid函数作为控制函数用来抑制抖振,并根据PMSM的反电动势模型构建了反电势观测器来提取所需的连续信号,因此取消了传统的一阶低通滤波器和相角补偿环节。为了对电机的转子位置和转速进行更加精确的估算,引入了转子位置锁相环结构。在Matlab/Simulink平台基础上建立了4种不同的电流控制策略,基于新型滑模观测器PMSM无位置传感器三闭环控制系统仿真模型,分别对反电动势估算、速度估算、位置估算和突加负载扰动进行了仿真分析。仿真结果表明,该新型滑模观测器在4种不同的电流控制策略下,对电机转子位置和转速的估算、电磁转矩以及定子三相电流有着不同的影响,验证了该新型滑模观测器算法的可行性。

To achieve the vector control of permanent magnet synchronous motor（PMSM） lies in obtaining accurate information of the rotor position and speed. A new sliding mode observer（SMO） based on the current strategies is proposed to investigate the control of PMSM servo system. To solve the problems of the high frequency chattering phenomena and the phase delay of back-EMF（ electromotive force） estimation in the conventional SMO, the new SMO introduces sigmoid function as the control function which is used to restrain chattering, and a back-EMF observer is constructed to extract the required continuous signal based on the PMSM back-EMF model. The low-pass filter and phase compensation are deleted. To estimate motor rotor＇s position and speed more precisely, the rotor position phase-locked loop structure is introduced. Based on the current control strategies and the same controller, a MATLAB/Simulink simula- tion model of PMSM three loop control system using the new SMO is given, and the back-EMF of the new SMO, velocity, position esti- mation and load disturbance are simulated. Simulation results show that the new SMO based on the four different current control strategies have different effects on motor rotor position, velocity estimation, stator three phase current and electromagnetic torque, and simulation results also verify the feasibility of the new SMO algorithm.