The Design Of DSP Control System Applied To Three Phase Brushless DC Motor

The advancement of electronics technology, motor technology and microcontroller technology accelerate the development of the electro-mechanical industry. Since the brush abrasion and arc-shaped mechanism for phase exchange are avoid, the system with Brushless DC motor controlled by microcontroller is more stable and has longer natural life than one with brush DC motor that commonly used. The application of power electronics devices greatly reduces the volume of control system. So this kind of control structure is used extensively in industry and civilian projects and with a wonderful view in the field of servo system.Hereby, the operation principle of three phase brushless DC motor is analyzed; the mathematics model of BLDC motor and the dynamic model of the control system are set up. Find out why the torque ripples appear and how to eliminate them.The hardware and the software of DSP control system applied to the three phase brushless DC motor of 48V/800W are designed. The hardware includes the system power, three Phase inverter circuit and minimum system taking TMS320LF2407 as the core. The software includes the generation of the PWM signal,the position sensor signal input and velocity modulator. At the same time a great deal of experiments for the selection of the power devices and the design of the drive circuit are made, as well as how to generate the SPWM signal and how to design the modulator of PID on DSP are studied.The whole and the half bridge modulation experiments aimed at the diverse work modes of inverter circuit are separately made, using the PWM to modulate velocity. In conclusion, the experimental results are analyzed and the comparison between this system and the MC33035 motor control system on their performances is made.The paper is to make some tracking research work based on the latest application of the motor control, facilitating the future scientific research. The experimental results show that the system controlled by BLDC motor run well, and upgraded easily, which supplies the reference for the following research work.