Study On Supercapacitor Energy Storage System Based On Urban Rail Transit Vehicle

In urban rail transit system, how to stabilize DC electric network fluctuation has been important study subject. An energy storage medium is much concerned about as primary method. Supercapacitor which is rapidly charged and discharged, offers long life, maintenance-free, low pollution and high efficiency, has been developed in wide range. Therefore, we carried out studies about supercapacitor energy storage system on board and presented control method to stabilize electric network. All of this is prepared for actual application of supercapacitor in urban rail transit.In urban rail transit, in powering or accelerating, supercapacitor is discharged, and the DC electric network voltage heighten; In inertia running, supercapacitor keeps the state; In braking and decelerating, supercapacitor is charged, and rest energy in DC electric network is stored. By switching amount three states above, DC electric network voltage avoid huge fluctuation and improve electrical energy qualityIn this paper, we study and produce experiment platform of supercapacitor energy storage system. By controlling the load of DC motor, it can simulate fully traction power supply diagram of urban rail transit. Based on that, math module is established, and after analyzing the transfer function, double loops of voltage and current is put forward.The double loops of voltage and current control scheme designed in the paper is simulated by Matlab. The result indicate that it not only stabilize DC electric network voltage but also ensure stability, rapidity and precision performance. In final, a series of experimental study proved that hardware design of supercapacitor energy storage system is wished.