电力系统自动化Issue(16)：126-131,6.DOI:10.7500/AEPS20150116003
一种距离保护Ⅲ段防过负荷误动的方法
A Method of Distance Protection Zone Ⅲ Capable of Preventing Overload Maloperation
摘要
Abstract
In view of the inability of traditional distance protection zone Ⅲ to correctly identify the difference between overload and fault,this paper specifically analyses the differences in electrical characteristics such as overload and fault from current asymmetry degree,Ucos φ and the variation of voltage phase.A new method for identification of overload and fault is proposed,which is based on current asymmetry degree and the difference between fault arc voltage and the minimum system voltage and voltage phase change.This method not only realizes the identification of symmetric overload and fault,but also solves the identification of the asymmetric overload and the high resistance grounding fault by comparison of changes in voltage phase.Through real-time digital system (RTDS) simulation,the results show that the method is capable of preventing maloperation of distance protection zone Ⅲ caused by overload while unblocking distance protection zone Ⅲ when fault does happen.关键词
潮流转移/距离保护Ⅲ段/电流不对称度/过负荷Key words
power flow transfer/distance protection zone Ⅲ/current asymmetry degree/overload引用本文复制引用
李辉,宋斌,胡钰林,李友军..一种距离保护Ⅲ段防过负荷误动的方法[J].电力系统自动化,2015,(16):126-131,6.基金项目
国家电网公司大电网重大专项资助项目(SGCC-MPLG003-2012)。This work is supported by State Grid Corporation of China,Major Projects on Planning and Operation Control of Large Scale Grid(No.SGCC-MPLG003-2012) （SGCC-MPLG003-2012）
