Study on the Influence of Aging and High Impedance Faults on Line Loss of 10kV Distribution Line

Abstract

With the rapid development of economy in China, the distribution network structure of China tends to be complicated. The overhead line is affected by environmental factors so that aging and high impedance faults occur, which increases the line loss and is not conducive to reliable and economic operation of the power system. In order to analyse the influence of aging and high impedance fault on the line loss of distribution network, this paper firstly establishes the mathematical model of the aging of 10kV distribution line, in which the impedance variation of each type of line with different operating years is obtained based on the actual measurement data. Then, the high-impedance grounding additional loss model under different grounding medium is established by experimental statistics. Finally, taking a distribution network as an example, the equivalent resistance method is utilized to calculate and analyse the influence of aging and ground faults on the distribution network loss. The results of the example show that on the one hand, the line loss of the distribution network increases exponentially with the operating period, and the line loss rate of the line with a long operating period easily exceeds the line loss standard; on the other hand, the high impedance fault will greatly increase the line loss rate for distribution network of smaller scale.