直流系统故障支路综合保护与隔离技术研究

Research on Comprehensive Protection and Isolation Technology of Fault Branch Circuit in DC System

直流支路是变电站直流系统最常发生故障的区域,现有的绝缘监测系统只能进行故障报警,故障定位和隔离主要还是依赖专业人员借助检测装置手工完成。为此,提出了适用于变电站直流系统故障支路的综合保护与隔离技术,并进行了保护装置的设计与开发。通过实验验证,该综合保护装置在直流支路发生短路故障时能迅速切断短路电路,发生环网故障、绝缘降低、交流窜入和接地故障时,能将故障限制在故障支路内,保证直流母线的正常运行。

The DC branch is the most frequently faulty area in the DC system of the substation.The existing insulation monitoring system can only perform fault alarm,and fault location and isolation mainly rely on professionals to complete manually with the help of detection devices.Therefore,a comprehensive protection and isolation technology suitable for the faulty branch of the substation DC system is proposed,and the protection device is designed and developed,which is verified by experiments.The comprehensive protection device can quickly cut off the short-circuit circuit when a short-circuit fault occurs in the DC branch,and can limit the fault to the faulty branch when a ring network fault,insulation drop,AC intrusion and grounding fault occur to ensure the normal operation of the DC bus.