变压器套管CT极性测试方法分析

Transformer bushing CT polarity test method

主变套管电流互感器的极性关系到二次主变差动保护方向,现行的测试方法,直流感应法测量不准确、测量难,存在产生过电压的隐患。本文从从直流感应法存在的问题出发,提出了新的测量方法:电容放电测量法,利用LC阻尼震荡产生的正弦波,通过电路转换成方波型号,进行测量,通过MATLAB仿真,进一步验证了结果,采用此方法设计了一种新的变压器套管CT极性测试仪。

Main transformer bushing polarity of current transformer is related to the second direction of main transformer differential protection, the current test method, dc induction method measuring inaccurate and dififcult, existence of overvoltage hazard. This paper starting from the problems existing in the dc induction method, puts forward a new measurement method： capacitance discharge measurement method, using the LC is shaken damping sine wave, by ChengFangBo circuit conversion model, measure, through MATLAB simulation, further verify the results, this method was adopted to design a new kind of transformer bushing CT polarity tester.