Research On Lightning Protection Measures Of 35kV Yingjiang Transmission Line

Lightning stroke is the main reason to cause line tripping and service interruption, meanwhile, lighting surge wave, which introduced by lightning stroking to transmission line, invading into substation over the line also is the key factor which impact on the safe operation of the substation equipment. So the study on the lighting protection of the transmission line is very popular all around the world.In China, 35kV line mostly adopt neutral non-grounding mode of operation and the system will not trip while the single-phase ground fault happens, it's difficult to analyze and calculate the lightning protection perfonnance using classical prescriptive method of China. So, in this thesis, aiming at the fact that a 35kV line stroked by lightning frequently in Chongqing, ATP-EMTP simulation program is applied to simulate and analyze the lightning back-flashover performance and shielding failure performance of two typical types of pole in 35kV transmission line and the lightning invasion wave performance of 35kV substation. The lightning back-flashover performances for the various spans of line, the various surge ground-resistances of poles, the various heights of poles, the various insulation levels and installing or not installing line gap are learned. This research can offer a thesis-support for the operation and the lightning protection design of 35kV power systems.The results of this research suggests that, the lightning back-flashover perfonnance and shielding failure perfonnance will be improved better with the decreasing of span, the decreasing of surge ground-resistance, the decreasing of pole heights and the increasing of insulators, height rising of poles and it will be improved much better when the line gaps are installed; the shielding failure trip radio is far smaller than the back-flashover trip radio; The lightning invasion wave is intercepted and attenuated remarkably for the protection of The shield wire of substation incoming lines and lightning arrester in substation, and the substation equipment are protected effectively.