中文摘要：

为提高高速铁路雷击防护能力,首先分析了现有高速铁路防雷体系的缺陷,并利用电气几何模型和实测数据分析了无避雷线时高速铁路牵引供电系统的雷击特性。研究结果发现：当高架桥平均高度为16m时,直击雷次数接近无高架桥时的2倍;由于雷击线路周边引起的感应过电压可基本忽略,因此传统的感应雷防护方法基本无效;随着高架桥高度的提高,直击雷与感应雷引起的绝缘子闪络次数所占比例不断提高。最后给出了高速铁路牵引供电系统防雷体系的改进方法,如采用专用避雷线;并指出了这种防雷体系与电力系统中的反击雷防护的不同,即当高架桥高度为16m、综合接地系统冲击接地电阻〈3.9Ω时,感应雷的危害已经超过了反击雷。

英文摘要：

In order to improve the lightning protection performance of power supply systems for high-speed railways,the defects of existing lightning protection system of high-speed railways were discussed,and the lightning characteristics of high-speed railway traction power supply system were analyzed based on electrical geometric models and measured data.It is found that the number of direct lightning strokes on a viaduct with average height of 16 m is nearly as 2 times as much as that without viaduct.Since the induced overvoltage caused by lightning surrounding of lines can be ignored,traditional ways of induced lightning protection have little effect.With the increasing viaduct height,the proportion of insulator flashovers caused by direct lightning strokes and induced lightning among all insulator flashovers increases continuously.Moreover,some improvement methods of lightning protection for high-speed railway power supply systems,like adopting reserved special grounding wires,are proposed.Meanwhile,the difference between the lightning protection system and the anti-counterattack-lightning protection of tradition transmission power systems reveals that,with a viaduct height of 16 m and an impulse grounding resistance of integrated grounding system less than 3.9 Ω,the threat of induced lightning is more than that of counterattack lightning.