Design Of Brushless DC Motor Controller Based On Nine-point Controller

Brushless DC moter is a new motor accompanied by the rapid development of the power electronics and pernemant magnetic materials technology. Because of its simple structure, high reliability, good speed-moduling performance,it has been widely used in many fields.Conventional control methods have shortages as design complexity, complex debugging, robustness. The nine-point controlling algorithm combines the advanteages of easy design, good stability, anti-interference ability between logic control and non-linear control method.In this paper,I use DSP Builder hydrid modeling design method with the FPGA as controlling core,to desgin a brushless DC motor control system based on the nine-point controlling algorithm.In the paper, according to the development and work theory of brushless DC motor,many methematical models of brushless DC motor such as multy-phase voltage equation, electromagnetic torque equation, motion equation had been disgussed and researched to establish the framework of th entire system.Comparing with the PID contronling theory, the dynamic and static performence have been researched and analysised,based on the nine-point controlling theroy,to support farther controlling system disgussion.In the system designing,the design of the hardware platform with the core of high-performence FPGA have been made, which includes the current detection circuit, speed detection circuit, PWM and the dead-zone protection circuit, photoelectric coupling circuit.With the designing of controller,the hybrid modeling desigin method using the Simulink/DSP Builder has been used to build brushless DC motor model with MATLAB/Simulink standard library,build the controlling module with DSP Builder library.After the complex algorithm design with DSP Builder, the data acquisition and controlling module intergration on FPGA controlling chip.The system modeling and simulation experiment finished in the MATLAB/ Simulink.Comparing with the PID contril method,the simulation waves show the nine-point controlling method performs a better dynamic and static performence.