Analysis on fault of loose connection of terminals in secondary circuit of current transformer

Abstract

Abstract: Abstract:A false trip accident of generator differential protection, which was caused by poor contact of secondary circuit of current transformer, was described. Using the circuit model of current transformer, the mechanism of overvoltage fault caused by opencircuit of secondary winding of current transformer was analyzed. The opencircuit test of secondary circuit of current transformer was carried out in laboratory. The relationship between the overvoltage and the primary current was verified qualitatively. At last, several methods to check the poor contact of secondary circuit of current transformer were given.

Key words: Keywords:current transformer, secondary circuit, overvoltage, differential protection, false trip, poor contact

WANG Song1, WU Pengyue2, SUN Ganghu2, WANG Zhigao1, GAN Jianghua3. Analysis on fault of loose connection of terminals in secondary circuit of current transformer[J]. Huadian Technology, 2015, 37(4): 19-21.

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Analysis on fault of loose connection of terminals in secondary circuit of current transformer

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