The Research Of Bldc Motor Nonlinear Dual Mode Switch Control

Brushless DC motor not only has characteristics of simple structure, reliable operationand easy maintenance like AC motor, but also has features of high operating efficiency, noexcitation loss and good speed control performance like DC motor, meanwhile, it hasflexible control method. Therefore it is used more widely. Control accuracy, stability andanti-jamming capability is an important factor to measure the level of overall systemperformance, and to make the system has high control accuracy, stability and stronganti-interference ability, the choice of control method is very important. In order to furtheroptimize the motor control performance, it is necessary to design appropriate controllerand reasonable controller parameters.In the industrial production process, the PID control is a control algorithm which isthe most widely used by far. The traditional PID control has simple algorithm, goodrobustness and high reliability, which is applicable to build the deterministic controlsystem of an accurate mathematical model. However, in modern industrial productionprocess, the system often meet delay link, and delay seriously affects the stability ofsystem, which leads to big change of system overshoot, the lengthening regulating time,even appear oscillation, divergent, and make the system dynamic quality drop greatly.Brushless DC motor is a complex system which is multi-variable, nonlinear, time-varying,and strong coupling. If still using the conventional PID controller, it is more difficult toadjust the PID parameters, which is difficult to meet the dynamic response and requirementof high performance and high precision. In order to solve this problem, this thesis designs adual mode switch controller, which is intelligent control method of combination of fuzzyPID control and sliding mode variable structure control. This control mode, realizingreducing chattering at the same time, not only has strong robustness to the modeluncertainty and external disturbance, but also has fast convergence and higher controlaccuracy, which can satisfy the control requirement of brushless DC motor.Finally, the brushless DC motor control system will be designed, which is based on TMS320LF2407A DSP of TI Company, including the system hardware and softwaredesign. At the same time, in the Maltab/Simulink platform, the simulation result not onlydemonstrates that the intelligent control is better than the PID, and the former hascharacteristics of the faster response speed, smaller overshoot, and better stability, andshow that the proposed scheme is feasible, and controller design is reasonable, and it hascertain practical value.