一种新型的三相异步电机控制方法

A novel control way of three-phase asynchronous motor

三相异步电机通过坐标变换可实现定子励磁电流分量和转矩分量的相互解耦,但是不能改变其为一个多变量、非线性被控对象的本质,并且传统的三相异步电机PI的参数在运行中固定不变,不能使控制系统随着外界因素的变化而适时跟踪变化。针对这一问题,在传统的矢量控制系统中引入了模糊的PI控制思想,利用模糊控制理论设计出了一种新型适用的模糊PI控制器。模糊控制不依赖被控对象精确的数学模型,能够克服系统非线性因素和电机运行时外界因素的影响,并对被控对象的参数变化具有较强的鲁棒性。在仿真和实验时还采用了多采样率转子磁链观测控制,多采样率能改善系统的稳态性能。采用多采样率的模糊控制三相异步电动机,通过仿真和实验验证可知,该控制方法能改善电机的静动态响应性能,提高系统的鲁棒性。

Three-phase asynchronous motors can achieve the mutual decoupling of the stator excitation current and torque component through the coordinate transformation, but can not change its nature of multi-variable, non-linear controlled object, and the PI parameters of conventional three-phase asynchronous motor are fixed in operation, and it can not make the control system in real time track changes with the changes of environmental factors. To solve this problem, fuzzy PI control method was introduced into the traditional vector control system, using fuzzy control theory to design a new type of suitable fuzzy PI controller. Fuzzy control as an intelligent control method does not rely on the precise mathematical model of controlled object, able to overcome the nonlinear factors and the effects of environmental factors when motors operates, and has strong robustness to the parameters changes of the controlled object. Multi sampling rate rotor flux linkage observation control improving the static performance was used in simulation and experiment. The results show that the fuzzy control method can improve motor static and dynamic response performance and the robustness of the system.