Application Research On Inverter Feedback Device In Urban Rail Transit

As urbanization continues to accelerate, the increase of urban population leading to exacerbate of urban traffic congestion, which affects people’s daily work and life seriously. As a new city subway transport, which is high speed, stop short distance, frequent starting and braking characteristics, has become an effective way to solve the city’s rapid transit. But domestic metro widely uses resistance regenerative braking energy absorbing device, which causes a lot of energy waste, tunnel temperature and other issues, so the paper studies on regenerative braking energy absorption devices.First of all, according to the working principle and characteristics of current domestic consumption resistance, capacitive energy storage, flywheel energy storage and inverter feedback regenerative braking energy absorption mode, the paper adopts inverter feedback type of regenerative braking energy absorption. By comparing completely replace, partial replace with new added inverter feedback device, the paper adopts an independent new program from consideration of the technical, reliability and economy.Then, the main circuit of feedback device is designed, and main circuit power switching elements, DC side capacitor, AC side inductance is calculated and chose. According to the mathematical model of the main circuit PWM converter, outer voltage, current inner double closed loop control system is designed. Its current loop is PI control based on synchronous rotating coordinate system, and pulse width modulation technology uses SVPWM technology. On this basis, the control system voltage outer PI and current inner PI parameters are set.Finally, by MATLAB software a simulation model of the inverter feedback device is established. Inverter feedback device that can inverter locomotive braking energy to the medium voltage network has good static and dynamic response, and inverter voltage and current can meet the GB/T14549-93 standard. Inverter feedback device applied to the single vehicle and large bilateral traction power supply systems, which can quickly inverter locomotive braking energy, and DC voltage is stabled in a safe range.