Research On Lightning Protection Of 35kV Collecting Lines In Large Wind Farms

Lightning strike on the lines of wind farms has long been a major problem,which has become more and more serious in recent years.This not only has a destructive effect on all kinds of equipment in the collector line,but also threatens the safety of the power grid.This paper comes from the practice unit(kunming survey and design research institute)has been put into operation of the "xiaoqingshan wind farm" as an example,through the use of simulation software pscad,explore the single and double lightning arrester to the collector line into the line section of the lightning protection effect,as well as the relationship between grounding resistance and tower strike lightning resistance level.Specific analysis methods and research contents are as follows:Use computer software to carry on the analysis,determine the research set of 35 kv electric circuit of the main causes of lightning trip-out rate is high,and then through the combination of theory and the selection of simulation software pscad analysis method,simulation of wind set electric circuit,electric circuit simulation analysis set by lightning,mainly through collecting line into line research about wire lightning resisting level of its influence,and analyses the reason of excessive grounding resistance of tower lightning strike,explores the lightning resisting level of grounding resistance of concrete segment.The following conclusions are drawn:1.When the incoming line is protected by double lightning arresters,the lightning resistance level of counterattack and lightning resistance level around the incoming line are improved,and the lightning trip rate of the incoming line is significantly reduced.2.It can be known from the research on the anti-lightning resistance level of tower of over-standard grounding resistance that their anti-lightning resistance level is lower than the minimum value to ensure the safety of the line,so lightning strike trip accidents are frequent,and then through multiple groups of experiments that the antilightning resistance level of tower is inversely proportional to the ground resistance.This paper introduces the relevant theoretical knowledge and lightning protection measures in detail,and carries out simulation experiments and analyzes the test results.Aiming at the lightning protection problem of "xiaoqing mountain wind farm" collector circuit selected in this paper,the corresponding solution is proposed,which is of great significance to improve the power supply safety of wind farm.