电力建设2018，Vol.39Issue(6)：49-55,7.DOI:10.3969/j.issn.1000-7229.2018.06.007
一种基于极性判别的环状直流配电网线路后备保护方法
Study on the Back-up Protection Method for Loop DC Distribution Lines Based on Polarity Discrimination
摘要
Abstract
Longitudinal differential protection methods applied to DC lines are widely used in transmission and distribution systems in our country because of their high reliability and good operation results have been obtained.However,with the rapid development of distributed generation in the distribution network,the threshold value is not easy to be set when high-impedance fault occurs,and the reliability of the protection action is poor.Traditional protection method for distribution network is not suitable for the ring DC distribution system.In this paper,a method of longitudinal protection based on the slope of sudden current change is proposed.First of all,the direction of the sudden current change at both ends of DC distribution line are analyzed.Then,it is proposed to introduce the slope direction into the direction detection of the sudden current change.Using the polarity relationship of the fault current signal in the low frequency band,a backup protection method capable of accurately operating for the DC distribution line is realized.Finally,a simulation model is built in MATLAB / SIMULINK.Simulation results show that this method has strong capability free from jamming and the affection of transition resistance,and to accurately identify the fault range and to improve the backup protection reliability to a certain extent.关键词
多端环状直流配电/纵联差动保护/电流突变量斜率/后备保护Key words
multi-terminal loop DC distribution/longitudinal differential protection/slope of sudden current change/back-up protection分类
信息技术与安全科学引用本文复制引用
孙丽敬,张海,刘瑛琳,罗国敏,吴鸣..一种基于极性判别的环状直流配电网线路后备保护方法[J].电力建设,2018,39(6):49-55,7.基金项目
国家自然科学基金项目(51507008) （51507008）
国家电网公司科技项目(EPRIPDKJ[2016] 2252)This work is supported by National Natural Science Foundation of China(No.51507008) （EPRIPDKJ[2016] 2252）
State Grid Corporation of China Research Program (No.EPRIPDKJ[2016] 2252). （No.EPRIPDKJ[2016] 2252）
