低速大转矩永磁同步电机矢量控制研究

Study on Vector Control of Low-speed and Large-torque Permanent Magnet Synchronous Motor

低速大转矩永磁同步电机调速系统在负载频变时存在动态响应慢的问题,本文分析了永磁同步电机数学模型、无传感器控制和自抗扰控制原理后,提出了一种基于滑模观测的自抗扰控制方法,并将其应用于矢量控制中,以提高永磁同步电机的运行性能。与传统滑模观测器相比,该方法的观测器是采用饱和函数sat作为开关函数,并引入锁相环得到转子位置估计值的方法,来减小估计误差。此外,再对滑模观测器的输出值进行动态跟踪与实时补偿来设计出适用于永磁电机的自我补偿型自抗扰控制器,并将该方法应用到永磁同步电机矢量控制系统中。仿真结果表明:采用自抗扰控制器的矢量控制系统具有更好的抗扰动能力和跟踪精度,电机满载启动时无超调,负载转矩突然变化时,系统能快速响应。

The low-speed and large-torque permanent magnet synchronous motor speed control system has the problem of slow dynamic response when the load frequency changes. This paper analyzes the permanent magnet synchronous motor mathematical model, sensorless control and active disturbance rejection control principle. An active disturbance rejection control method based on sliding mode observer is proposed and applied to vector control to improve the operating performance of permanent magnet synchronous motors. Compared with the traditional sliding mode observer, the observer of this method uses the saturation function as the switching function, and introduces a phase-locked loop method to obtain the rotor position estimation value to reduce the estimation error. In addition, dynamic tracking and real-time compensation are performed on the output value of the sliding mode observer to design a self-compensating active disturbance rejection controller suitable for permanent magnet motors. And this method is applied to the vector control system of permanent magnet synchronous motor. The simulation results show that the vector control system with active disturbance rejection controller has better anti-disturbance ability and tracking accuracy. There is no overshoot when the motor starts at full load, and the system can respond quickly when the load torque changes suddenly.