Objective Bidirectional converter technology is an important direction in the application technology research of intelligent and green urban rail transit traction power supply. Due to the differences in external characteristics of bidirectio-nal converter devices and rectifier units, it is necessary to carry out relevant research and optimize the application scheme of bidirectional converter devices, thereby improving the matching performance of power supply to the traction network between the two.

Method Based on the current design specifications, a standard working system selection method applicable to bidirectional converter devices is proposed, and an equipment capacity configuration principle for traction substations with bidirectional converter devices is determined. Then, the '1+1' mode and '1+2' mode configuration schemes for bidirectional converter devices are put forward. Different main wiring schemes and their applicable scenarios are proposed and analyzed from the perspectives of power supply reliability and harmonic content. Taking a certain urban rail transit line as an example, the equipment capacity and main wiring scheme of the traction substation with bidirectional converter devices are reasonably selected, and simulation calculations are carried out for the line. Based on the simulation results, a technical and economic comparison is conducted between the '1+2' mode confi-guration scheme of bidirectional converter devices and the traditional rectifier unit configuration scheme.

Result & Conclusion The installation of bidirectional converter devices in the traction power supply system can enhance the utilization level of train regenerative braking energy, reduce electric energy loss of the catenary. Furthermore, it can significantly reduce electricity expenses during the service life, thereby reducing operation and maintenance costs.