Design And Simulation Research Of Fuzzy Control System For BLDC Based On DSP

Brushless DC motor(BLDCM) is a kind of electromechanical integration machinery, and it has been rapidly developing in recent years with the help of the development of power electronic technique and the appearance of new type of permanent magnet material. The use of sensorless control reduces the size of BLDCM, lowers its costs and reinforces its interference immunity, thereby widening its application areas. As a consequence, the research on position-sensorless control for BLDCM has been a hot spot all along in recent years.Based on analyzing and summarizing some problems existing in former BLDCM control system, we introduce one kind of sensorless control system for brushless DC motor based on DSP. This new family of DSP TMS320F2812 enables cost-effective design of intelligent controllers for brushless motors which can fulfill more conditions, consisting of fewer system components which can fulfill more conditions, consisting of fewer system components, lower system cost and increased performances. This thesis establishes the whole simulation model for the sensorless BLDCM Drives, A new back electromotive force (EMF) detection method was presented for the sensorless control system of BLDCM; the control structure, technology, strategy and chip are confirmed by the timing principle; The hardware circuit is designed based on TI's DSP-TMS320F2812 and IR's driving chip-IR2133; Working out initialization programmed of some main components and the whole frames, the software programs is written with assemble language of DSP and C.In following parts, there is a detail description of controller's design about BLDC motor. In controller's design parts, the characteristics of Fuzzy-PID controller are presented in detail. And in the Matlab environment Fuzzy-PID controller with self-adjusting parameters is designed and modeled.The end is modeling and simulation research of control system. In Matlab/Simulink environment, the isolated functional blocks, including BLDC general block (including BLDCM block, torque computation block, rotation speed computation block, the back EMF block), Current hysterics control block, Speed control block, rotor position computation block, voltage source inverter block etc, have been modeled. By the organic combination of these blocks, the model of BLDC can be established easily. In the double loop of control system, a Fuzzy-PID controller with self-adjusting parameters is adopted in the speed outer loop and a current hystersis controller is adopted in the inner loop. The reasonability and validity have been testified by the simulation results and also verified that Fuzzy-PID controller with self-adjusting parameters is superior to traditional PID controller and the former has fast response speed,little overshoot and good stability and tracking performance. This novel method offers a new throughway for designing and debugging actual motor control system.