Research And Simulation Of Urban Rail Transit Super Capacitor Energy Storage System

In recent years, the subway construction entered the stage of rapid development with the economy of our country continuously developing, and our country will put more subway lines and subway trains into operation for the next few years. Facilitative urban rail system has brought great convenience for citizens, but also brought a rapid increase in energy consumption. Since China is a country where energy is relatively short, it become urgent and necessary to explore ways of subway train energy saving based on the analysis of energy consumption.In this paper, the energy storage system of urban rail super capacitor has been studied. First, we made research about the principles and characteristics of super capacitor energy storage system based on introducing regenerative braking energy absorption system, then proposed its equivalent model and voltage balancing strategy.Secondly, this paper described the current application status of super capacitor energy storage system, analyzed the regenerative braking energy absorption devices general design, the general hardware and software design. The general hardware design includes a sampling circuit design, hardware failure detection and protection circuit, the general software design includes its general structure and software flowcharts. A discussion about the working principle of super capacitor energy storage system in urban rail transport from both hardware and software aspects in detail has been proposed.Meanwhile, bidirectional DC-DC topologies are analyzed in detail in this paper, which designed a bidirectional DC-DC circuit of complementary PWM control mode, made bidirectional DC-DC converter by mathematical modeling, and made simulation by using MATLA-B/SIMULINKE software, and made analysis under the control status super capacitor’s charge-discharge characteristics.At the end of this paper, a double closed-loop structure of urban rail super capacitor energy storage system control strategy proposed, based on considering the super capacitor’s charge-discharge characteristics, and using MATLAB/SIMULINKE simulation software to build the system model, approximately simulate the real operation of urban rail conditions. Simulation results show that the designed super capacitor energy storage system and the control strategies achieved better objective control and functional requirements, with energy storage, network voltage stability traction usage, got engineering value in some degrees.