Research and application of power grid capacitance current plus signal singlerate measuring method

WANG Zhijin，WANG Zongxin

( Department of Infrastructure, Hebei University of Engineering,Handan 056038,China)

Abstract: When highvoltage power system grounded for singlephase,the current flowing through the point of failure increases dramatically, this resulted in a very strong ground overvoltage arc gap. In order to solve this problem,the method of capacitive current plus signal power measurement was analyzed in detailed,the necessity of measurement of the power capacitor current was  fully demonstrated and the additional signal power singlefrequency capacitive current method of measuring the controller was reserved, the plus singlefrequency signal measurement with the other methods of measure was comparedThe results show that the capacitive current plus singlefrequency signal measurement is more accurate, especially when the large power system damping, or the displacement of lowQ circuit voltage is very small, singlefrequency signal is applied to show the advantages of measurement better,laying the foundation for the design and application of the grid capacitive current measurement

Key words: grid; capacitive current; external signal; singlefrequency measurement