高湿度高土壤电阻率地区风机防雷接地案例探讨

Discussion on the Lightning Protection Grounding Cases of Wind Turbines in Areas with High Humidity and High Soil Resistivity

为解决高湿度高土壤电阻率地区风力发电机组(以下简称风机)接地设计复杂、降阻难度大、与风机配套的箱式变压器(以下简称箱变)低压侧易发生雷击事故等问题,通过CDEGS仿真软件对同类工程进行算例演示,发现单纯降低土壤电阻率的方法对减小雷击过电压效果并不明显,防雷接地设计时不能仅从降低接地电阻一方面考虑,而是要将风机及其配套箱变的防雷接地设计作为一个系统工程来研究,找到技术可行且经济合理的处理方案。经验可供同类风电场设计、运行、检修人员参考。

Wind turbines in areas with high humidity and high soil resistivity face problems such as complex grounding design,difficulty in reducing resistance,lightning accidents which often occur on the low-voltage side of box-type transformers matched with wind turbine.Through the demonstration of similar projects by the CDEGS simulation software,it is found that lightning overvoltage cannot be effectively reduced by simply reducing soil resistivity.The lightning protection grounding design of the wind turbine and the box-transformer should be carried out systematically other than reducing the grounding resistance in order to find a technically feasible and economical solution.The experience can serve as a reference point for design,operation and maintenance personnel of similar wind farms.