Abstract: Metro platform screen door is an important part of urban rail transit system. To ensure power supplying of screen door control system is an essential requirement for metro operating with safety and reliability. According to the demand of direct current uninterrupted power system (DC UPS) for the metro platform scree doors, a DC/DC power supply module based on the LLC half-bridge resonant topology is firstly designed to fulfil the soft-switching in full load range. The module has the virtues of high conversion efficiency, high power density and well regulation, etc. Secondly, a piecewise nonlinear droop control strategy is proposed to realize autonomous and adaptive current sharing between the power supply modules and thus improving the trade-off design between current sharing and output voltage regulation. The design procedure for main parameters of the LLC DC/DC power module is described, and two power modules prototypes with rated power of 600 W are built to validate the design of power modules and their autonomous current sharing performance.