Application Of Lightning Protection Technology To220kV Multi-circuit Transmission Lines Of The Same Tower In Dongguan Grid

Located in South China coastal areas, Dongguan has obvious characteristics of oceanclimate, whose Lightning density Forefront of the province and the country, and belongs tothe strong lightning activity. Furthermore, the lightning activity showed a general upwardtrend in recent years.Within the above-mentioned objective environment of strong lightning activity, the tripfault in Dongguan Grid occurs yearly because of lightning.Through the statistics of transmission lines’s lightning trip cases in Dongguan area inrecent years, results indicate that the total numbers of lightning trip show an upward trend inrecent years within Dongguan area, especially the total numbers in2009and2010is higherthan that of in other years. It is often that the trip occurs during critical period of the summerpeak, so as to make a great impact on the supply for covered area.The operation experience of the above-mentioned lines shows that the lightning trip onMulti-circuit Transmission Lines of the Same Tower has made up a great proportion of totallines lightning trip faults. Because the high Transmission capacity on Multi-circuitTransmission Lines of the Same Tower, the lightning trip at the same time will result inserious load loss, system instability and the scope of the accident expansion. So that, it isnecessary to keep a look-out on lightning flashover rate and the simultaneous lightning triprate.This paper will make study on the technology application of lightning protection in220kV multi-circuit transmission lines of the same tower, including simultaneous lightningflashover characteristic of multi-circuit transmission lines of the same tower in differentvoltage level, evaluating on the operation characteristic of multi-circuit transmission lines ofthe same tower, to develop countermeasures to reduce the rate of lightning fault.Aiming at the optimal configuration of countermeasures for the simultaneous lightningtrip of multi-circuit transmission lines of the same tower, this paper will establishes systematictheories and guiding principles to supply reference for improving the level of lightningprotection on multi-circuit transmission lines of the same tower.The countermeasures configuration of reducing the lightning flashover rate, proposed bythis paper, can provide technical guidance on lightning protection design and renovation andhas broad application prospects and significant economic benefits. By applying the above countermeasure, the technical level of lightning protection inDongguan grid will be improved, especially that of study and prevention on the simultaneouslightning trip of multi-circuit transmission lines of the same tower.