基于振荡中心电压的对称性故障开放新判据  

New Power Swing Unblocking Criterion of Symmetrical Fault for Line Protection Relay based on Oscillation Center Voltage

作　　者：李斌 郑玉平 陈瑞俊 

机构地区：[1]江苏省电力公司检修分公司,南京210000 [2]南瑞集团,南京210000

出　　处：《电气技术》2017年第6期59-63,共5页Electrical Engineering

摘　　要：本文利用计算电压为一余弦函数且在系统振荡时等于振荡中心电压、而在三相短路时的其值不大于电弧电阻上的压降的特征,并考虑在振荡时的一个较短的时间内,可认为计算电压是匀速变化的特点,提出了一种振荡中对称性故障开放判据。当计算电压在0附近小区间内停留的时间超过计算获得的预期时间时,说明发生了对称性故障,开放保护动作。新判据与振荡周期自适应,易于整定,易于实现。仿真结果证明了该判据的正确性和有效性。A new Power Swing Unblocking Criterion of Symmetrical Fault for line Protection Relay is presented in this paper. The defined calculated voltage is equal to the voltage at the swing center during power swing, while it keeps less than arc voltage when a Symmetrical Fault is occurring. What is more, The defined calculated voltage can be considered as uniform changing in a short range, which makes the stay time of calculated voltage in the range can be calculated. According to these characters, An adaptive power swing unblocking criterion is presented. The new criterion is easy to use in current relay protection.

关 键 词：线路保护 振荡闭锁 对称性故障 余弦函数 自适应 

分 类 号：TM711[电气工程—电力系统及自动化]