开关磁阻电机最优分数阶PID^μ控制器设计

Design of optimal fractional-order PID^μ controller for switched reluctance motor

开关磁阻电机(SRM)调速系统中的PI控制器通常表现出动态性能差、控制精度低和转矩脉动大的问题,加入微分环节的PID控制器虽然可以有效提高控制性能,但因PID控制器具有微分环节,较大的系统噪声容易引起震荡,造成电机运行不稳定。针对这一矛盾,引入分数阶微分环节,设计了一种分数阶PID^μ控制器。选择系统的速度响应构建目标优化函数,采用灰狼优化算法整定控制器参数得到最优参数。搭建SRM双闭环调速系统仿真模型,速度环采用分数阶PID^μ控制方式,电流环采用电流斩波和脉冲宽度调制(PWM)分时控制方式。将转速突变和负载突变作为干扰,对PI控制器和分数阶PID^μ控制器的控制性能进行对比实验。结果表明,所设计的参数最优分数阶PID^μ控制器保留了PI控制器结构简单,设计方便的优点,同时表现出更快的响应速度和控制精度,对SRM转矩脉动具有很好的抑制作用。

In the switched reluctance motor speed control system, PI controllers often exhibit problems of poor dynamic performance, low control accuracy and large torque ripple. The PID controller can effectively improve the control performance, but because the PID controller has a differential link, a large system noise is likely to cause oscillation, resulting in unstable operation of the motor. To solve this problem, a parameter optimal fractional-order PID^μ controller is designed based on conventional PI controller. The speed response of the system is selected to construct the target optimization function, and the gray wolf optimization algorithm is used to adjust the controller parameters to obtain the optimal parameters. The double loop model of SRM speed control system is established, the fractional-order PID^μ controller is adopted in the speed loop and a compound current controller and PWM controller are adopted in current loop. The performance of conventional PI controllers and fractional-order PID^μ controllers is compared in the case of sudden changes in speed and load transients. Simulation experiments show that the fractional-order PID^μ controller retains the advantages of simple structure and convenient design of the PI controller. At the same time, it exhibits faster response speed and control precision, and has a good inhibitory effect on SRM torque ripple.