Application of Distribution Network Current Differential Protection Based on Ubiquitous Internet of Things in Line Selection and Location of Small Current Grounding System

Abstract

In order to find the fault point of one-phase grounding in distribution network as soon as possible and prevent instantaneous fault from developing into permanent fault or inter-phase short circuit, Tongxiang Electric Power Company of Jiaxing, Zhejiang Province adopts neutral point flexible grounding system, which solves the difficulty of fault location and avoids the malpractice of frequent tripping of the system. Based on the communication mode of power wireless private network, the feasibility of implementing fast differential protection in distribution network by using improved mutation algorithm is analyzed through MATLAB simulation. Under the influence of overhead line, cable line, the first or the end of line and transition resistance in flexible grounding system, differential protection can effectively reduce the extension of fault range, improved the relay protection level of distribution electric network to meet the reliability requirements of power supply system.