不受汲出电流影响的方向式四分段双母线保护  

Directional 4-segment double-bus protection immune to outgoing current

作　　者：姜宪国 王增平 李琛 

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京102206

出　　处：《电力系统保护与控制》2012年第20期68-72,78,共6页Power System Protection and Control

基　　金：国家自然科学基金重点项目(50837002);高等学校博士学科点专项科研基金项目(20110036110003)~~

摘　　要：提出了一种不受汲出电流影响的方向式四分段双母线保护方案。分析了四分段双母线内部故障时汲出电流对传统母差保护和方向式母线保护的影响。针对二者存在的缺陷,提出一种母线连接支路等效方法,将可能产生汲出电流的支路等效为一条支路。利用正序故障分量方向元件测量各支路中的故障方向,在此基础上提出了母线保护的动作逻辑,实现故障判断,并分析了母线相继故障时的应对方案。仿真分析表明,该方向式四分段双母线保护不受母线故障汲出电流影响,需要同步数据量少,能够抗CT饱和、系统振荡和过渡电阻的影响,保护可靠性高,动作特性良好。A directional 4-segment double-bus protection scheme immune to the outgoing current is proposed. The effect of the outgoing current flowing from a fault bus on the traditional bus differential protection and directional bus protection is analyzed. To cope with the drawbacks of the two kinds of bus protection, a branch equivalent method is proposed. The branches which may emerge outgoing current are combined into one branch. The positive sequence fault component directional element is used to identify fault direction. Based on that, a bus protection action logic is presented to identify faults. In addition, the countermeasure to the successive bus fault is discussed. Simulation analysis demonstrates that this bus protection scheme is immune to the outgoing current when a fault occurs on the bus, needs less synchronization data than the current differential scheme, and has good performance to overcome the impacts of CT saturation, system oscillation and transition resistance. The protection is reliable with favorable operation characteristics.

关 键 词：汲出电流 四分段双母线 母线保护 正序故障分量方向元件 同步数据 

分 类 号：TM773[电气工程—电力系统及自动化]