电工电气
電工電氣
전공전기
Electrotechnics Electric (Jiangsu Electrical Apparatus)
2015年
10期
16-20,28
,共6页
周斌%卜京%汤雪松%游步新
週斌%蔔京%湯雪鬆%遊步新
주빈%복경%탕설송%유보신
电流互感器%虚拟制动%相对磁链积累%差动保护
電流互感器%虛擬製動%相對磁鏈積纍%差動保護
전류호감기%허의제동%상대자련적루%차동보호
current transformer%virtual brake%relative lfux linkage accumulation%differential protection
为解决利用时差法识别区外故障后闭锁差动保护期间发生区内故障,导致保护延时动作的问题,结合虚拟制动电流采样点检测CT饱和方法,提出了引入相对磁链积累变化情况及交流量幅值特征作为开放保护的辅助判据,并利用相对磁链累积一周波内的方差来代表变化情况以及最小二乘法拟合得到二次电流的交流幅值,以达到正确识别转换性故障的目的。通过四种工况仿真表明,该法提高了抗区外故障的饱和能力,保证了保护的可靠性和灵敏性。
為解決利用時差法識彆區外故障後閉鎖差動保護期間髮生區內故障,導緻保護延時動作的問題,結閤虛擬製動電流採樣點檢測CT飽和方法,提齣瞭引入相對磁鏈積纍變化情況及交流量幅值特徵作為開放保護的輔助判據,併利用相對磁鏈纍積一週波內的方差來代錶變化情況以及最小二乘法擬閤得到二次電流的交流幅值,以達到正確識彆轉換性故障的目的。通過四種工況倣真錶明,該法提高瞭抗區外故障的飽和能力,保證瞭保護的可靠性和靈敏性。
위해결이용시차법식별구외고장후폐쇄차동보호기간발생구내고장,도치보호연시동작적문제,결합허의제동전류채양점검측CT포화방법,제출료인입상대자련적루변화정황급교류량폭치특정작위개방보호적보조판거,병이용상대자련루적일주파내적방차래대표변화정황이급최소이승법의합득도이차전류적교류폭치,이체도정학식별전환성고장적목적。통과사충공황방진표명,해법제고료항구외고장적포화능력,보증료보호적가고성화령민성。
To solve the delay action of protection when the external faults change to be the internal faults during the block of differential current protection, based on the method of testing current transformer saturation at virtual brake current sampling point, this paper proposed to introduce the characteristic of relative lfux linkage accumulation and the amplitude of the current as a new criterion to open the protection, using the relative lfux linkage accumulation variance at one cycle and the real-time least square (RLS) algorithm to obtain the amplitude of secondary current, so as to distinguish the transferring faults accurately. Four kinds of working conditions simulation shows that this method resists external faults saturation more strongly to ensure the reliability and sensibility of protection.