CT饱和对继电保护动作的影响分析  

The influence of CT saturation on the operating of relay protection

作　　者：张吕根 

机构地区：[1]望亭发电厂,江苏苏州215155

出　　处：《电力系统保护与控制》2003年第S1期21-25,共5页Power System Protection and Control

摘　　要：电流互感器(CT)饱和时,电流继电器能不能正确动作,一直存在二种载然不同的观点。在实际运用和设计中,也存在这种状况。电流互感器到底允许不允许饱和,饱和倍数达到多大时,电流继电器就不能正确动作,事实上这个问题长期以来是没有解决。从正弦波电流面积积分这一角度出发,通过计算推导出当CT的-10％误差倍数K和继电器定值A已知时,能使继电器动作的最大CT电流倍数C与K、A之间的数学关系式为:A≤C≤(4A^2+K^2)/4A。从而找到了这个问题的数学答案。There are two different points of view on whether current relay operates correctly or not, when CT saturates. Such kind of thing also esists in the practical application and design. Is CT saturation allowed ? How many times of CT saturation does the current relay not operate at correctly ? In fact the problem has never been solved. This article gets a formula: A≤C≤ basing on integral calculation of sine wave current area. The formula indicates a range in which current relay operates correctly, while K is the times of - 10% error of CT, A is the set value of relay, C is the maximum current times of CT. And this is the math result of the problem.

关 键 词：CT饱和 电流型继电器 电磁型保护 微机型保护 

分 类 号：TM77[电气工程—电力系统及自动化]