| Brushless DC motor has many advantages such as simple in structure, reliable operation, high operating efficiency, no excitation loss, excellent speed adjusting performance etc. These traits make brushless DC motor has wide application prospect and research value in computer peripherals, office automation equipment, household appliances, automobiles, medical equipment and other areas. TMS320F28x series are DSP produced by TI corp. and are specially used in industrial area which has powerful digital signal process ability and several on-chip peripherals which is very suitable for BLDC control system.In this paper, a relatively complete mathematical model of brushless DC motors is built based on the knowledge of brushless DC motor structure and working principle. Referring to the home and abroad research situation of Brushless DC motor, the paper brings about the DSP-based high-speed (100000rad/min) high-power (5kw), Brushless DC motor intelligent control system design, containing hardware circuit and the software programming towards the high voltage and current.TI's TMS320F2812 controller chip is used as the system control core. The system use Hall element as a position feedback mechanism. In order to achieve closed-loop control of motor speed, the system gives speed control to Brushless DC motor while constantly collecting feedback from the motor actual speed Hall to amend the control of speed. The system hardware architecture is divided into control, drive, power supply, display five blocks circuits, and magnetic coupling is used to isolate circuit boards. Control board is the core of the whole system, and it undertake the system's control functions, including motor speed detection, control and perimeter protection of electrical safety work to start the additional equipment, etc. It contains the DSP interface circuit, MAX485 communication circuits, fault alarm circuit and so on. On the driver board, we mainly use the power driver IC IR2181 to drive three Simon Kang SKM100GB128D modules in order to control motor speed. At the same time the hardware system also contains digital keyboard and LCD screen to implement real-time control and display motor running status.The software design of the system consists of two parts, DSP software design and host computer software design. DSP software design includes DSP motor control module in program design, MyBIOS operating system design and related design of the interrupt service subroutine. Motor speed control algorithm used in this system is PID algorithm. By collecting motor speed and comparing with the command speed, the PID algorithm is used to control speed and constantly modify the value given, in the end motor speed can be stable on the feature we set. VB programming is used to prepare the operation of motor control interface on the host computer, and apply RS485 communication programming to achieve data exchange. The computer interface contains all the necessary control of motor function keys. Through the operation on a computer, control instructions can be easily given to control the brushless DC motor.In the end of this paper, the brushless DC motor intelligent control system was debugged and tested, and a BLDCM prototype is completed. On the base of prototype, a serial of test has been done and at the same time the result and analysis of the test is exhibited. Experiment indicates that the prototype can work stable, has high control accuracy and good load ability. It can be widely used in some field.
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