克服母线差动保护汲出电流的对策  

Countermeasures to Overcome Outflow Current for Bus Differential Protection

作　　者：杜丁香[1] 周泽昕[1] 王兴国[1] 艾淑云[1] 周春霞[1] 李仲青[1] 

机构地区：[1]电网安全与节能国家重点实验室,中国电力科学研究院,北京市100192

出　　处：《电力系统自动化》2014年第24期86-90,共5页Automation of Electric Power Systems

摘　　要：针对母线比率差动保护的大差元件在区内故障有汲出电流情况下,由于元件动作灵敏度下降可能导致保护整组动作速度减慢或拒动的问题,提出了改进判据及具体实现方案。首先,分析了对于双母线及双母线双分段接线形式母线汲出电流对常规母线保护的影响。然后,提出了新型比率差动判据中制动电流的计算方法,并分析了区内、区外故障时新判据的特性。最后提出了与小差元件配合的具体实现方案,并通过动模实验验证了算法及方案的有效性。The outflow current during an internal fault on the bus will decrease the sensitivity of the relays for the overall differential element and even lead to operation refusal or trip time delay for the total protection. To solve the problem, improved criteria and a concrete implementing scheme are put forward. First, the influence of outflow current on conventional bus protection for double-bus and double-bus double-segment connection modes is analyzed. Then, the restraint current calculation method of the new ratio differential criterion is proposed and the characteristics of the new algorithm during internal and external faults are analyzed. Finally, the implementation scheme matching small range differential relay is put forward and the validity of scheme is verified by dynamic simulation test.

关 键 词：母线保护 汲出电流 比率差动 差动保护 

分 类 号：TM773[电气工程—电力系统及自动化]