The Mechanism Research On Lightning Tripping And Assessment Of Lightning Performance In 10kV Distribution Lines

10k V distribution line is important in power system. With the development of society and economic, requirement for power supply’s reliability has been increasing. As it has complex truss structure and low insulation level in 10 k V distribution line, power failure often happens by direct lightning and induction lightning. Therefore, the study of lightning protection measures for improvement of the circuit and accurate assessment of the lightning resisting level in transmission line is of great importance in reducing lightning accidents and increasing power supply’s reliability.Firstly, this article analyzes the l0 k V distribution line’s basic and operating parameters in the Guangdong province. It then studies the distribution network lightning tripping’s mechanism, which concludes that the insulation level and the grounding method are main factors that affect the lightning tripping in the 10 k V distribution. Next, major factors of lightning tripping are analyzed. In addition, this article studies and analyzes the calculation method and characteristics of the induced overvoltage.Secondly, this paper introduces the grid structure between high voltage lines and distribution lines, the different feature of lightning protection. It compares the defending effects of the six frequently-used measures and methods of high voltage lines and distribution lines, pointing out measures that improve lightning withstand level. Also, it provides the evidence for assess power lightning protection.Finally, the article is based on the improved analytic hierarchy process(AHP) with new scale and fuzzy comprehensive evaluation method(FCEM). Considering the reduction of trip-out rate, the impact of engineering cost, the effect of the target, as well as the ease of maintenance, service life and other factors, this article constructs a suitable lightning protection assessment model of distribution network to evaluate the lightning protection measures of actual lines. The results show that the evaluation system can effectively assess the distribution lines, and determine the optimal rehabilitation of lightning protection.