分布式小电流接地保护研究与应用

Research and Application on Distributed Small-current Grounding Protection

提出了一种分布式小电流接地保护方案,在35kV及以下线路保护装置中集成以暂态量为主、稳态量为辅的单相接地检测功能。装置基于本间隔信息完成本线路是否发生单相接地故障的初步判别,并通过既有的站控层网络共享判别结果,各装置综合比较本装置和其他装置的判别结果,并完成智能跳合闸操作。该方案不仅可以降低设备投资、简化二次回路、优化运维管理,而且可以提升接地选线的准确性和普及率。

A distributed small-current grounding protection scheme is proposed, which integrates the single-phase grounding detection function with the transient amount as the main and the steady-state quantity as the auxiliary in the line protection device of 35 kV and below. The device performs the preliminary determination of whether the single-phase ground fault occurs on the line based on the interval information, and shares the discrimination result through the existing station control layer network. Each device comprehensively compares the discrimination results of the device and the others, and completes the intelligent trip and close operation. This solution can not only reduce equipment investment, simplify secondary loop, optimize operation and maintenance management, but also improve the accuracy and penetration rate of grounding line selection.