Research On Speed Regulating System Of Brushless DC Motor Vehicle For Mine

Brushless DC motor is a new type of AC motor developed after the brush DC motor. It is named by the characteristics which are no phase inverter on the rotor and no brush on the stator. It inherites the tradition of a wide range of DC motor speed, strong overload capacity and good starting characteristics, etc. And it also has a simple structure, never wear, low failure rate, energy efficiency and high reliability, which have broad application prospects in mining transport system.DTC is a new type of variable frequency speed control technology after vector control technology. DTC uses the analysis method of voltage space vector. By directly controlling the stator flux and electromagnetic torque, the frequency conversion speed regulation makes come true. It not only saves the complex vector transform and the processing of the mathematical model of the BLDCM, but also can realize the optimal control of the power switch tube in the three-phase drive circuit. And it has a simple and reliable structure, control directly without encumbrance, etc, which become a main developing direction of modern motor control system.The main research object is brushless DC motor vehicle.First, it introduces the ontology of BLDCM, basic working principle of rotor rotation and the three phase full bridge driving circuit in detail. Secondly, this chapter introduces the balance equation of voltage, the electromagnetic torque equation, the motion equation and transfer function model. The control principle of the direct torque control strategy is analyzed in detail. The simulation model is built by MATLAB/Simulink, and the waveform of phase current, phase voltage and motor speed are analyzed. Thirdly, This paper focuses on the hardware circuit of BLDCM vehicle. The hardware circuit uses TMS320F28335 as the main controller and it takes the rotor position detection circuit, the protection circuit and the auxiliary power supply as peripheral circuit. These designs can make BLDCM speed control system own the advantages of reasonable structure, easy to realize and control stability. After the completion of the circuit design, it simulates the operating environment of BLDCM vehicle. The motor speed is set to 1000r/min. The waveform of the pulse signal and the phase voltage of the power switch tube are measured by the oscilloscope. Then, it analyzes its rationality. Then, by designing the Software flow charts of the main program, the timer interrupt subroutine, the A/D and D/A subroutine and the liquid crystal display subroutine, it can achieve the positive, stop, reverse running and frequent acceleration and deceleration of the function in the BLDCM speed control system in the end. Lastly, summary of the full text, and set the future research direction and research objectives.