Abstract: In the context of constructing energyefficient urban rail transit systems in China, it is necessary to study the utilization of electrical energy generated by regenerative braking in urban rail transit power supply system. Method: Taking an actual line in Xuzhou Metro equipped with BC (bidirectional converter) devices as example, the external characteristics including constant voltage and droop for rectifier unit and BC device synergistic working scheme (rectifier+BC scheme) are analyzed. The running performance measurement analysis on the scheme that completely adopts BC devices (all BC scheme) is carried out. The reactive power compensation in depot equipped with BC devices is also analyzed. Result & Conclusion: Under external characteristics of constant voltage, as the starting voltage increases from 1 550 V to 1 650 V, the rectification output power of the BC device increases while the rectifier unit output power decreases under the same conditions. The rectification output power decreases progressively when the BC device collaborates with 12pulse and 24pulse rectifier units. The BC device can replace the rectifier unit and operate independently, performing rectification and inversion functionality. When the reactive power compensated by BC device increases to 0.5 MVar and 1.00 MVar respectively, the average capacitive reactive power on main substation 110 kV side decreases sequentially by 0.49 MVar and 1.00 MVar, verifying the effectiveness of the BC device reactive power compensation function.