Research on and Application of Fault Disposal in Flexible Interconnection Distribution Network

The application of flexible DC technology in distribution network can realize closed-loop operation of multiple feeders and flexible regulation of power flow. It provides a new solution for large-scale distributed power friendly access and high reliability power supply. This paper introduces the model and control method of back-to-back flexible DC in detail. According to the operation characteristics of the flexible interconnected distribution network, a cooperative fault recovery strategy among the master station, flexible DC control system and protection devices is proposed. The power supply capacity analysis model of flexible DC device with passive load is established. Finally, based on the actual situation of the flexible DC in Suzhou, a typical fault is taken as an example to elaborate the fault disposal process. This paper provides references and experiences for the operation of other AC-DC hybrid distribution networks.