Research on the circulating current suppression strategy of parallel operation of multiple cophase supply devices

摘要

At present, the traction supply system of electrified railways has adopted phase rotation power supply technique, the power supply mode results in electrical phase-splitting of the contact line, which reduces the capacity and safety of electric locomotive. By ensuring the output voltage strict accordance of each phase power supply device, smooth cophase power supply system can be constructed, completely cancel the electric phase-splitting, but multiple cophase power supply device through the parallel power supply will bring line circulation problem. Therefore, this paper analyzes the parallel circulation problem of the electric railway in cophase power supply system, using the control theory of non reciprocal connections, a general circulation suppression strategy is proposed for the parallel operation of multiple cophae power supply devices. The simulation results show that the parallel control strategy can effectively restrain the circulating current in traction network, which can greatly improve the capacity of the line.