电力系统保护与控制2011，Vol.39Issue(3)：40-45,6.
20Hz注入式定子接地保护在扩大单元接线发电机组上的应用
Application of injecting 20 Hz source-based stator ground fault protection for generators in expanded unit connection
摘要
Abstract
At present, the stator ground fault protection of generator through injecting 20 Hz voltage cannot be used in generators connected to expansion units due to lack of selectivity. This paper proposes an improved protection scheme to realize the selectivity. The proposed scheme firstly calculates the ground resistance value of generators to determine whether ground fault occurs. When the ground fault is detected, the 20 Hz differential current between the neutral and terminal of each generator can be obtained. The phase relationship between the 20 Hz differential current and injected 20 Hz voltage is derived. The new protection scheme can determine the fault generator according to the phase relationship, so that it can achieve a selective shutdown. The simulation results verify the accuracy ofcalculating the grounding transition resistance and selecting the fault generator, which realizes the application of the injecting stator ground fault protection in the generators connected to expanding units.关键词
扩大单元接线/发电机/注入式/定子接地保护/接地变压器Key words
expansion unit connection/ generator/ injecting source/ stator ground fault protection/ earthing transformer分类
信息技术与安全科学引用本文复制引用
刘春秋,葛宝明,毕大强..20Hz注入式定子接地保护在扩大单元接线发电机组上的应用[J].电力系统保护与控制,2011,39(3):40-45,6.基金项目
中国电机工程学会电力青年科技创新项目资助 （）
