500 kV交流线路复合绝缘子并联间隙应用研究

为了设计和开发性能优良的的超高压输电线路并联间隙防雷保护装置,开展了绝缘子串并联间隙的相关研究,包括其雷电冲击放电特性试验、操作冲击放电特性试验、工频短路电流试验和工频电压分布研究。提出了一种兼具绝缘子防雷保护和工频电场均压功能的环形并联间隙,并评估了加装并联间隙后的500 kV交流线路的耐雷性能。研究结果表明,所设计的并联间隙具有绝缘子雷击闪络保护、转移疏导工频电弧和均匀电场分布的功能,使得平原地区架空线路加装并联间隙后雷击跳闸率低于0.14次/(100 km.a)。

Research on the Application of Composite Insulator Parallel GapL in 500 kV AC Transmission Lines

In order to design and develop parallel gap lightning protection devices with high performance, the related studies of insulator string with parallel gap are carried out in this paper, including its lightning impulse performance test, switching impulse performance test, power frequency short circuit current test and power frequency voltage distribution. A ring type parallel gap is proposed, which has the functions of both lightning protection and electric field voltage equalizing. The lightning performance of 500 kV transmission lines with the ring type parallel gap is evaluated. The research results show that the designed parallel gap has functions of lightning flashover protection, AC arc transfer and AC voltage equalizing, and thus the annual rate of lightning trip-out of 500 kV lines with parallel gap can be lower than 0.14 times/（100 km.a） in plain regions.