Design And Implement Of BLDC Motor Controll System Based On ST7FMC

The permanent magnet brushless DC motor is a DC motor using electronic communication in place of mechanical communication in fact, so it has excellent characteristic of DC motors, for example good start and timing performance. It simplifies the motor's structure and overcomes the friction disadvantages of ordinary DC motor, because it doesn't use mechanical communication. It is extensively used in aviations, robots, digital machine tool and so on. These years along with the development of power-electronics technique and micro-control technique, permanent magnetic brushless DC motor is characterized by small volume, light weight, high efficiency, low noises, big stand-alone capability and reliability appeared and matured. So it is hopeful to become new generation electric propulsion motor.The great development of digital signals processors and hardware chips help to realize permanent magnetic brushless DC motor's fast and reliable control. STMicroelectronics offers a new 8-bit controller ST7FMC1K2, specifically designed for the needs of digital motor control. This chip integrated many BLDC motor control periphery circuit, suited specially in BLDC motor control, which provide reliable and the highly effective signal processing and the control hardware for the high performance, it had the very high performance to price ratio.Taking the actual request of BLDC motor controller of electrically operated bicycle as a background, BLDC motor classic PID control system was designed and implemented in this article. Hardware design of BLDC motor control system including the basic expand of ST7FMC1K2, drive circuit and current-detecting circuit and software design of the digital PID algorithm are used in the system. Finally the experimental confirmation has been carried on to the entire control system, the question was analyzed in the experiment and the improvement method was proposed. Fuzzy approach control system of BLDCM is simulated. Above all, the approach of Fuzzy PID controller is designed, especially the confirming of the fuzzy control rules. Relative to classical PID controller of which three parameters are fixed .Fuzzy PID controller can regulate the three parameters in the dynamic control according to controlled object. The result of simulation shows, the adoption of Fuzzy PID controller can make the system have better performances such as quicker response, smaller over shoot and the steady-state error. The simulation has some value to the real system.