接触网安装避雷器的防雷效果研究

Research on Lightning Protection Effect of Lighting Arrester on Catenary

研究目的:雷电过电压严重威胁电气化铁路牵引供电的可靠性,在接触网上装设避雷器是降低雷害的措施之一。但接触网避雷器的防雷效果还没有可供参考的理论分析。本文以我国接触网绝缘子的绝缘强度和雷电流的概率分布为基础,运用接触网雷击跳闸的概率模型计算比较接触网是否安装避雷器的雷击跳闸情况。研究结论:通过研究分析表明:由于电气化铁路接触网外绝缘水平较低,容易在雷电过电压下发生支柱绝缘子连续闪络是一个显著的特点,在分析接触网耐雷水平和各种防护措施的效果时忽略这一特点都会带来很大的误差。避雷器并不适合广阔区间的分散式的防雷方式,而是在雷击比较密集的地点采取密集的安装方式才能取得很好的防雷效果。

Research purposes： The over-voltage of lighting seriously threats the reliability of power supply to the electrified railway.To install the lighting arrester on the catenary is one of ways to reduce lighting disaster,but now there is no theory on analysis of the lighting protection effect of lighting arrester on catenary.In this paper,based on the insulated strength of insulator of catenary and possibility distribution of lighting current,the analysis is made for the tripping situation caused by lighting when there is and there is no arrester on the catenary.Research conclusions：The research shows as the external insulation level of the catenary of electrified railway is low,the insulator on support post is easy to flash over continuously under the over voltage of lighting.The attention should be paid to this when making analysis of the lighting-resistance capacity of the catenary and taking measures for lighting protection,otherwise,the big error will be brought out.The arrester is not suitable for the distributed lighting protection way in broad area,but it can obtain good effect for the lighting concentrated area with installation of it concentratively.