Study On The Lightning Protection Of The Regional Transmission Grid

The current transmission grid is in danger of lightning is still safe and reliable operationof the main factors, the State Grid Corporation in 2003 on statistics show that China's 500kVtransmission line in lightning trip line trip accounted for 46%, 330kV transmission line inlightning trip line trip accounted for 29 %, 220kV transmission line in lightning trip line tripaccounted for 33.4%, 110kV transmission line lightning flashover in line trip accounted for35.3%. In Japan, more than 50% of the power system accident caused by lightning; the UnitedStates, Russia and other 12 countries of 275kV ~ 500kV transmission line to run for threeconsecutive years of data show that lightning disturbance 60% of the total accidents.Therefore, the transmission line lightning protection is essential. In recent years, running theunit attaches great importance to the transmission line lightning protection work, and part ofthe line has been transformed, but lightning caused transmission line tripping accidents stilloccur frequently.As our country is located in the temperate (subtropical climate in some areas), so themore intense lightning activity. Long transmission lines crossed the plains, mountains, acrossrivers and lakes, and geographical conditions encountered in different weather conditions,with large differences in the distribution of lightning activity, so the chance of transmissionlines being struck by lightning more. According to statistics, China's electric power system,various types of accidents, obstacles, transmission and distribution lines, lightning damageaccidents account for a large proportion. As the power transmission lines for the protection ofthe safe operation of a very important position, how to reduce incidents of lightning damageto transmission line power system security and stability become an important topic.Based on the lightning trip and topography, terrain, the structure of the line itself,lightning protection angle between line and regional transmission grid in the section oftransmission line lightning trip Louis hit rate and influencing factors, find the line subjectedto lightning shielding and the trip back the law, take appropriate lightning protection fortargeted measures to reduce the lightning disturbance, increase the level of mine resistantprovides an important reference, but also for other regions and design units provide animportant basis for mine design.