Back-to-Back PV Generation System and Its Control Strategy for Electrified Railway

Abstract

Integration of PV generation to traction power supply system helps to reduce energy consumption and emission of railway system and increase local accommodation of PV energy. This paper proposed a back-to-back PV generation system for electrified railway and a control strategy based on special characteristics of railway traction power supply system. The PV energy was output from DC side of the back-to-back converter and optimal current of each converter was calculated dynamically according to working conditions. In this way, two converters could be controlled independently and both reactive power and negative sequence were compensated with the redundant capacity of converters. In energy self-balance mode, local accommodation of PV energy was realized without influence on power quality of traction power supply system. Finally, a system simulation model was built and effectiveness of the proposed back-to-back PV generation system was verified.