配网线路避雷器雷电放电电流和吸收能量特性分析

Analysis on Lightning Discharge Current and Absorbed Discharging Energy of Surge Arrester on Distribution Line

配网线路避雷器雷击放电电流特性是其动作负荷、残压、型号选择、试验考核和运行寿命评估的关键依据.在建立配电网输电线路防雷计算模型的基础上,用电磁暂态计算程序ATP-EMTP对无避雷线的典型10 kV配电线路在不同雷击途径下流经线路避雷器的雷电放电电流和吸收的雷电放电能量进行了计算分析.研究了不同波形、幅值雷电流侵入时,不同杆塔冲击接地电阻下,线路避雷器的放电电流和吸收能量特性,分析了雷电流幅值、波形、冲击接地电阻对放电电流的幅值、波头时间、波尾时间和避雷器吸收能量的影响.研究结果表明:雷直击线路时,避雷器放电电流幅值和吸收能量均随冲击接地电阻阻值的增大而减小,而雷击塔顶时相反.

The lightning discharge current of arrester in distribution network is the key to its operating duty,residual voltage,model selection,test evaluation and operation life evaluation.On the basis of establishing lightning protection calculation model of transmission line,the lightning discharge current and lightning discharge energy of lightning arrester of 10kV distribution line without lightning line are calculated by using electromagnetic transient calculation program.Under the conditions of lightning current with different amplitudes,waveform and different grounding resistance,line arrester discharge current and the discharge energy are studied.The effect of lightning current waveform and grounding resistance on the discharge current waveform and the discharge energy are analyzed.The results show that when the lightning strikes conductor,the lightning discharge current amplitudes and lightning discharge energy are increasing with the grounding resistance,which is opposite to when the lightning strikes tower.