电力系统保护与控制Issue(16)：133-138,6.
CT过饱和特性及对过流速断保护的影响
Characteristics of CT over-saturation and its influence on over-current/instantaneous trip protection
胡家为 1葛荣尚 1尹明铉 1李明1
作者信息
- 1. 北京紫光测控有限公司，北京 100084
- 折叠
摘要
Abstract
In order to improve the reliability of over-current/instantaneous trip protection under CT over-saturation condition and avoid protection operation-failure, this paper presents a useful analysis method of the variation trend of the measurement value of the protection along with short current. The transfer characteristic and output waveform feature as well as measurment performance of relay protection device during CT over-saturation condition are analyzed. It is shown that when fault current is several times larger than CT rated accurate limit primary current (i.e. CT is over-saturated), the characteristic value on the CT secondary side monotonously increases slowly, but the measurement value of the protection devices may decrease along with the increase of the fault current, which causes the failure of the protection. The analysis method calculates the measurement variation trend of the short-circuited current to verify the reliability of the setting values of instantaneous over-current protection, therefore, some proper measures can be taken to avoid the protection failure under this condition. It will have good economy benefits in the real applications.关键词
电流互感器/准确限值电流/过饱和/测量值/过流速断保护/整定值Key words
current transformer(CT)/rated accuracy limit primary current/over-saturation/measurement value/instantaneous over-current protection/setting values分类
信息技术与安全科学引用本文复制引用
胡家为,葛荣尚,尹明铉,李明..CT过饱和特性及对过流速断保护的影响[J].电力系统保护与控制,2013,(16):133-138,6.
