Research On Permanent Magnet Motor Drive And Energy Feedback System For Mine Electric Locomotive

The mine electric locomotive is an important transportation tool in the mine.Its working performance and transportation efficiency play a key role in the production and development of the mine.Most of the current mining electric locomotives are driven by DC motors,but DC motors have many shortcomings,including slow starting speed,series resistance starting,high energy loss,large size and difficult to maintain.In order to solve these problems,this article Permanent Magnet Synchronous Motor(PMSM)is used instead of DC motor as the drive motor,and Direct Torque Control(DTC)strategy is used to control the operation of the motor.Braking energy feedback technology is also used to reduce the The electric locomotive is reused after the energy feedback during braking.First,construct the mathematical models of the permanent magnet synchronous motor mining electric locomotive under different coordinate systems,and use the DTC strategy to control the permanent magnet synchronous motor.Introduce the basic principle and switch vector table of the traditional six-sector PMSM-DTC system,and then analyze the proposed 12-sector PMSM-DTC system with sector subdivision and compare it with the traditional six-sector PMSM-DTC system.Comparing simulations,it is found that the proposed control strategy can significantly reduce the torque ripple produced by the permanent magnet synchronous motor,and has a better dynamic response in the control of the flux linkage,and it can be started with a large torque.Secondly,the braking energy feedback system is studied,the four-quadrant operation characteristics of the motor are analyzed and the equivalent model of Supercapacitor(SC)is constructed.The new hybrid energy storage braking energy feedback system is composed of the proposed switching quasi-Z-source bidirectional DC/DC converter connected to a super capacitor and connected in parallel with a battery.The converter proposed in this system adopts voltage/current double closed-loop control when it is electric,and adopts a constant current-to-constant voltage control method during energy feedback.Under this control strategy,the operation of the mine electric locomotive in the starting,constant speed and braking states is The braking system is simulated.It is found that the converter proposed can effectively reduce the voltage stress of the switching tube during the operation of the system,increase the bus voltage and suppress its voltage fluctuation;the super capacitor in the system can effectively recover braking energy through the converter proposed to increase the cruising range,and Extend battery life.Finally,with TMS320F2812 DSP as the core processor,the software and hardware design of the motor drive and energy feedback system of the mine electric locomotive was carried out,and the experimental platform of the motor drive and energy feedback system was built,and some experimental waveforms were recorded through experiments.From the experimental waveforms,it is concluded that the dynamic response of the acceleration and deceleration of the PMSM-DTC strategy in the motor drive and energy feedback system is better and there is no overshoot,which ensures the efficient and safe operation of the motor.Figure[59]Table[9]Reference[71]...