Dynamic Voltage Restorer Appied for Urban Rail Power Supply System

To solve the voltage sag problem in metro escalators, Dynamic Voltage Restorer (DVR) for urban rail power supply system is proposed in this paper. Firstly, the Dynamic Voltage Restorer designed in this paper draws energy from the DC traction network without additional energy storage elements, which solves the energy storage problem of the conventional Dynamic Voltage Restorer. Secondly, a single-phase full-bridge inverter circuit is used to achieve phase-independent voltage compensation so that various voltage sag can be handled. Thirdly, an improved proportional-resonant(PR) composite control strategy is selected to realize the voltage tracking of the DVR. Finally, A Hardware-in-the-loop simulation platform is used to conduct simulation experiments in this paper, and the simulation results show that the model proposed in this paper can accurately realize the effective compensation of voltage sag on the metro escalator and ensure the normal operation of the escalator.