关键词: 超级电容, 容量配置, Buck-Boost, 控制策略

Abstract:

Supercapacitor energy storage devices are used to realize the regenerative braking energy absorption functions in rail transit projects. These devices can be effectively used to solve the problem that the inverter feedback-type energy-saving device transmits the regenerative energy to the 110-kV main substation. Based on the train operation parameters in the actual project, mechanical and electrical analyses of the train-braking process are conducted. Further, an overall designs scheme of the energy-saving device with capacitor energy storage is proposed. The energy-storage-type energy-saving device includes a two-way chopper and a supercapacitor bank. The main circuit of the chopper adopts a staggered parallel two-way buck-boost circuit, and the supercapacitor bank adopts a series and parallel scheme. According to the voltage and current requirements of the energy storage device, several series and parallel configurations are designed for a supercapacitor bank. Based on the train model, rectifier unit, and energy storage device, a control strategy is designed for the chopper circuit in the energy storage device to realize energy storage during train braking and energy release during traction. Finally, the pulse-width modulator rectifier in its power-source mode is used as the train simulation source to simulate the traction and braking processes of the train. The control strategy of the chopper circuit and the charging and discharging characteristics of the supercapacitor are verified through experiments. Results show that the control strategy of the chopper circuit and the capacity configuration scheme of the power bank of the energy storage scheme satisfy the requirements of the source device.

Key words: super capacitor, capacity configuration, Buck-Boost, control strategy