Research On The Regenerative Braking Energy Feedback Absorption System Of Subway

Urban rail transportation has advantages of safety, punctuality,energy, speed, great capacity and protection of the environment and so on.The general consensus has formed around the world: The effective way to solve the problem of urban public transport is to build rail transport as the core of the public transport system. In recent years, with the rapid pace of urbanization in China, urban rail transportation has been developing.Subway has some characteristics,such as a short distance of the stations,the big run density.The frequent braking process for the train will produce a very rich renewable energy. Subway is mainly the research object In the paper. To solve the recycling problem of the subway train braking energy,the master-slave control strategy of inverter- resistor regenerative braking is proposed.First, several solutions of train regenerative braking energy were analyzed, and their advantages and disadvantages were compared, the paper chose the master-slave control strategy of inverter-resistor regenerative braking. In addition, according to the principle of dynamics,regenerative braking energy produced by subway train were calculated.Second, a simulation model of 24-pulse rectifier train unit and AC drive system are built. Through the simulation, power supply systems and the subway running condition include traction, coasting and braking were analyzed.Then, according to the basic principle of the inverter feedback devices, the simulation model of the inverter feedback system is build.The active damping LCL filter parameters, PI parameters of PLL phase-locked loop and control parameters of voltage outer and inner current loop are designed. Through the simulation of inverter network model, the inverter output voltage waveform, LCL filter output voltage waveform and traction network voltage waveform are obtained, and then changes from each waveform are analyzed.Finally, according to the principle of master-slave control strategy of inverter- resistor regenerative braking, the simulation model isestablished. Combined with the actual operation of the subway,the scheme of breaking energy used for the 0.4kV lighting system was simulated and verified in different situations, such as one train or multiple trains running at different initial velocity.