Sensorless BLDC Motor Control System Based On DsPIC30F2010 MCU

Due to the development of permanent magnet material, the permanent-magnet synchronism motor possesses many advantages of high efficiency, long service life, small volume, light in weight and simple structure, which has made it be widely applied in the fields of aeronautics and aerospace, military affairs, household electronic appliances and industry. Especially, the BLDC motor comes into wide use because it is simple in structure and control.With the rapid advancement of modern power electronics, the theory of control and microprocessor, the control technology of BLDC motor also has relatively gained great development. Although the BLDC motor has high power density, it also has some shortcomings. For example, the relatively poor operating performance limits its utility in high-performance environment. Therefore it will lay a firm foundation for the further applied of BLDC motor with qualities of simple structure and low cost that enhancing its performance in terms of the theory and technology of control. And this is the main purpose and significance of this thesis.This paper mainly researched on the sensorless control system of BLDC motors which were centering with microprocessor dsPIC30F2010, launched by Microchip Technology; It also strived to maintain the relatively simple control while improving the performance of the motor. It analyzed the inner structure, operational principle and control theory with circumstance in this paper. Besides, a relative mathematical model was built based on analysis. In addition, by the way of comparing with Rotor Position Detection, the zero-crossing point of fundameutal component based FIPS was put forward, which did the reversing control and velocity estimation to the BLDC motor. Moreover, the simulation result is counted and the feasibility of the system is verified by the simulation model of sensorless control system established by MATLAB/SIMULINK software platform. Integrating the utilized control tactics and functional module of microprocessor, the paper also researched hardware circuit, founded electric circuit cored with dsPIC30F2010, designed detection circuit of zero-crossing point, improved driving circuit of the power tube in three-phase bridge inverter,restrained the surge coursed by grid wave in power tube, which efficiently diminished the switching loss of power tube and meanwhile preserved the power tube.Finally, via testing the model machine, the paper gave out and analyzed the experimental result when the system was operated practically. The result had verified the validity and feasibility of sensorless control system.