10kV架空配电线路防雷措施配置方案分析

根据配电线路感应雷跳闸特征,建立了感应雷跳闸计算模型。通过感应雷跳闸计算模型,分析了10 kV配电线路在更换绝缘子、不平衡绝缘、采用绝缘横担三种方案的感应雷跳闸频率变化情况,得出:更换绝缘水平更高的绝缘子是提高10 kV配电线路耐雷水平的最直接措施;在同塔双回线路中,一相安装避雷器能使线路防雷效果提高50%以上,且安装在中相导线时的提高幅度更大。根据10 kV配电系统一般为中性点不接地系统,两相安装避雷器时,可使感应雷引起的跳闸事故大幅降低;对于绝缘子等配电设施容易损坏的配电线路,在允许一定跳闸率的前提下,可安装保护间隙。

Analysis on Configuration Scheme of 10 kV Overhead Distribution Line Lightning Protection Measure

An induced lightning trip computational model is established according to the induced lightning trip characteristics distribution lines.Based on the model,the induced lightning trip frequency change of the 10 kV distribution line on the situation of replacing insulator,unbalanced insulation and erecting insulated cross arm are analyzed and the result shows that: change the insulator with higher insulation level is the most direct way to improve the lightning withstand level of 10 kV distribution line;in case of double circuit line in the same tower,the lightning protection effect can improve by 50% when install a arrester on one phase,and the effect is greater when the arrester is installed on middle phase conductor.According that the 10 kV distribution system generally is neutral ungrounded system,the trip accident caused by induced lightning can be reduced sharply by installing arresters on two phases;for the distribution lines that distribution facilities,such as insulator,are easy to be damaged,under the precondition that allow a certain trip-out rate,the protection gap can be installed.