Research Of Mining Accumulator Locomotive Speed Control System Based On SMO

The battery locomotive used in coal mine as the main transportation equipment plays a crucial role in coal mine production. As the main traditional mining electric locomotive traction device, the performance of DC motor directly affects the efficiency of electric locomotive. With the development of variable-frequency speed regulation technology and power electronics, compared with the DC speed control system, AC speed control system has such advantages as high efficiency, good dynamic performance and maintenance. Therefore, AC speed control system has begun to replace the traditional dc speed control system gradually. As a new type of ac speed control system, switched reluctance motor speed control system is suitable for locomotive traction because this control system has such advantages as simple structure, flexible control, low failure rate and high efficiency.By studying the working mode and mathematical model of switched reluctance motor(SRM), a new type of switched reluctance motor speed control-system based on direct torque control is proposed for the reason for the disadvantage of higher torque ripple in the slow running process of switched reluctance motor. The performance of the control system is studied by simulation with MATLAB, and the results show that the switched reluctance motor speed control system based on direct torque control has the characteristics of low torque pulsation and fast response.Rotor-position sensors plays an important role in switched reluctance motor speed control system,but the high failure rate of the rotor-positon sensors has become the important factors that limit the development of SRM. An approach of SRM speed regulation without position sensors based on sliding mode variable structure control technique is proposed in this paper. By building nonlinear inductance model of the SRM and using sliding mode observer (SMO) to estimate the rotor positon for SRM, SRM speed regulation without position sensors is achieved. The system simulation shows that the method has high precision, great robustness and adaptability for rotor position estimation.Finally, the paper completes the hardware and software design of the motor speed control system for mine which is based on the high performance processing chip STM32F103VET6ARM kernel. The prototype experiment results show that the direct torque control system based on SMO effectively reduces the failure rate, improves the operational efficiency of motor speed control system for mine and can fit in with different complicated environments very well.