Research On Fuzzy Control Method Of Permanent Magnet Synchronous Motor Based On Model Reference

Permanent magnet synchronous motor(PMSM) has been widely used in the field of CNC machine tools, aerospace and electric vehicle because of its simple structure, high power factor,reliable operation and easy maintenance. In this paper, the salient pole permanent magnet synchronous motor and its control system are studied. The main research include how to suppress the influence of parameters and load disturbance on the system control performance,improve the system response speed and enhance the robustness of the system:(1) Firstly, the paper reviews the research status of control strategy and control algorithm about PMSM by making research of a large number of related references, then analyzes the development course of PMSM speed control system and expounds the background and significance of the research.(2) Secondly, the paper introduces the classification structure and working principle of PMSM and analyses the basic principle of vector control, then establishes the mathematical model of permanent magnet synchronous motor by means of coordinate transformation in three different coordinate systems and analyses the operation principle of double closed loop permanent magnet synchronous motor based on vector control. The engineering design method is used to determine the parameters of the speed regulator and current regulator.(3) Thirdly, the paper analyses the principle of model reference adaptive control based on adjusting gain, then analyses the basic principle of PID and fuzzy control and presents the design method of the fuzzy PI controller. The fuzzy PI adaptive control is introduced in the model reference control structure which is suitable for the control of nonlinear systems, then the paper establishes approximate two order model of the motor and designs the anti windup PI feedback controller by using limit integral weakening method and designs model reference adaptive fuzzy PI speed controller(MRFAC) which using fuzzy adaptive output to dynamically adjust the speed loop gain of feedback PI controller. Lastly, the paper build simulation model of PMSM control system with MRFAC and test control characteristics of the designed control scheme in response speed and anti disturbance.(4) In order to further enhance the adaptive ability of system, the paper analyses and introduces the sensitivity of model theory which is used to describe influence of parameters on the system, then designs a self-learning mechanism to dynamically adjust the fuzzy controllerparameters based on the sensitivity function. Lastly, a self-organizing fuzzy speed controller based on sensitivity function(SLFLC) is designed and applied to PMSM speed control system.The paper writes the sensitivity function program with S function builds the simulation model of the designed system with the help of software Simulink. The comparative analysis of two kinds of control scheme show that the MRFAC scheme has high control accuracy and good stability, it is suitable for low speed control occasions. SLFLC scheme has the advantages of faster response speed and stronger anti disturbance ability, and is suitable for high speed control occasions, the two kinds of control scheme both have good robustness.