配网灵活接地保护策略研究

Research on Flexible Grounding Protection Strategy of Distribution Network

本文提出全新的灵活接地保护控制策略。通过引入接地选线以及选线跳闸技术,解决高阻接地时零序保护不能动作跳闸的问题;通过为小电阻控制增加故障累积法策略,解决持续短时接地故障;通过为小电阻控制增加"后加速"投入策略,解决与线路保护以及各级DTU/FTU保护时序配合的问题。新保护控制策略及控制系统的应用,可以有效弥补当前灵活接地系统的运行盲区,使灵活接地系统发挥其应有效能。

A new flexible grounding protection control strategy is proposed in this paper. Through the introduction of grounding line selection and line selection tripping technology, the problem that zero sequence protection can’t act and trip when high resistance grounding is adopted;adding fault accumulation method strategy for small resistance control to solve continuous short-term grounding fault;adding "post acceleration" input strategy for small resistance control to solve the problem of coordination with line protection and DTU/FTU protection sequence at all levels. The application of the new protection control strategy and control system can effectively make up for the operation blind area of the current flexible grounding system, and make the flexible grounding system play its effective role.