重庆地区自渝500kV输电线路的防雷性能

鉴于500kV线路的重要性，以重庆地区500kV自渝输电线路为例，针对其特殊的地形、地貌，用规程法计算线路的雷击跳闸率（包括反击和绕击）、行波法计算线路的反击跳闸率、击距法计算线路的绕击跳闸率，分析影响雷击跳闸率的主要因素，比较计算结果，找出绝缘薄弱点、雷电易击段，并提出相应的改进措施。计算结果表明：畦电流陡度对反击跳闸率的影响很大，雷电流陡度越大，反击跳闸率越高；规程法计算反击还比较接近实际运行经验，计算绕击则存在明显缺陷；击距法（EGM）计算绕击跳闸率考虑的因素比较全面，评估避雷线对导线的屏蔽性能与实际更接近。

Lightning Proof Performance of 500 kV Transmission Line in Chongqing Area

Considering the importance of 500 kV line and taking 500 kV transmission line in Chongqing as an example, the authors calculate lightning strike outage rate (including return stroke and lightning shielding failure) using regulation method, outage rate of return stroke using travelling wave method, and outage rate of lightning shielding failure using EGM. By comparing and analysing the calculating fesults, weakness of insulation and the area of easy to striking are found out, and corresponding improving measure is brought forward. The results show bigger gradient of lightning higher return stroke tripping, and in regulations result of accounting return stroke tripping is more closed to practical experience, accounting shielding failure rate exists obviously defect, and in EGM accounting shielding failure rate have take much factor, result is more close to practical experience.