Study On Brushless DC Motor Velocity Adjustment Control System Based On Fuzzy PID Optimized By PSO Algorithm

Brushless DC Motor has not only the advantages of simple structure,reliable operation and easy maintenance of DC Motor, but also has the advantages of high efficiency,no excitation loss and easily adjusting speed of AC Motor.It has been widely used in the small and medium-sized power of the speed controll system of the industry control domain. However, it has the state of torque ripple and unstable speed.Based on this consideration,the research of the Brushless DC Motor speed control technology and methods has been done in order to obtain the more reasonably control effect in this paper.The traditional PID controller and fuzzy control technology have been widely applied in theory and practice. Combining both of these advantages,fuzzy control technology can be used to adjust the parameters of PID online. It is the basic thought of self-adaptive fuzzy PID controller. But fuzzy controller is a nonlinear controller based on expert experience essentially,which is devoid of effective design and adjustment method to determine control rules and membership functions of every fuzzy sets accurately.So, this paper proposes a design method of self-adaptive fuzzy PID based on PSO(PFPID). The PSO is a kind of evolutive calculational methods based on group brainpower. This algorithm is straightforward and easy to be implemented,and can obtain the optimal solution in the complicated spatial. The PSO algorithm is applied in the design method of fuzzy controller,which can on line adjust the quantization factors Ke,Kec and scale factor Ku automatically, then adjust the three parameters——kp,ki and kd of PID controller.It can realize fastest non -overshoot dynamic performance of the system very well.Therefore, this paper first introduces the basic component parts,the basic running principle and the mathematical model of the Brushless DC Motor in detail.By analyzing the problems that the traditional PID control and fuzzy control algorithm faced,and using advantages of PSO algorithm, according to the requirement of speed regulation system,an self-adaptive fuzzy PID controller based on PSO is designed.Then in matlab2009a/simulink window,the simulation model of Brushless DC Motor speed control system based on self-adaptive fuzzy PID optimized by PSO is established. Startup,controling-speed and changing-load performance of the motor has been studied. Contrasting to the conventional PID controller,the system has a better static and dynamic performance,and also has a strong adaptability for changes of the parameters and the load disturbance,and obtains the good control effcet.