雷击不同基杆塔下配电变压器雷电防护能力分析  

Lightning Protection Capability of Distribution Transformer Under Different Base Towers Struck by Lightning

作　　者：刘乐康 赵涛[1] 杨磊[1] 刘云鹏[1,2] LIU Lekang;ZHAO Tao;YANG Lei;LIU Yunpeng(Hebei Key Laboratory of Power Transmission and Transformation Equipment Safety and Defense,North China Electric Power University,Baoding 071003,China;State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University,Beijing 102206,China)

机构地区：[1]华北电力大学河北省输变电设备安全防御重点实验室,河北保定071003 [2]华北电力大学新能源电力系统国家重点实验室,北京102206

出　　处：《电瓷避雷器》2021年第5期1-8,共8页Insulators and Surge Arresters

摘　　要：10kV配电变压器作为输电和配电环节的重要枢纽,因其连接线路不沿全线架设避雷线导致绝缘能力不足,易遭受雷电侵害。本研究采用散射参数测量法,基于黑盒理论构建了雷击条件下配电变压器的宽频等效模型,且重点考虑雷击不同基杆塔时,配变内部过电压分布情况。利用ATP-EMTP进行仿真分析,研究雷击于不同位置时引起变压器套管或中性点闪络的最小雷电流值以及相应位置处过电压波形特性。仿真结果表明,低压侧套管绝缘为雷电防护的薄弱环节,易受雷击侵害。因此采用接地电阻阻值降低、并联电容器等方法来加强配电变压器的绝缘薄弱环节。As an important hub of transmission and distribution, 10 kV distribution transformer is vulnerable to lightning damage due to its insufficient insulation capacity caused by the fact that its connecting line does not construct lightning wires along the whole line. The scattering parameter measurement method is adopted and the broadband equivalent model of distribution transformer is constructed based on the black box theory under the condition of lightning strike, and the overvoltage distribution inside distribution transformer is mainly considered when lightning strikes different base towers. By using ATP-EMTP simulation analysis, the minimum lightning current value of transformer bushing or neutral flashover caused by lightning strike at different positions and the characteristics of overvoltage waveform at corresponding positions were studied. Simulation results show that the insulation of the low voltage side bushing is weak, particularly vulnerable to lightning strike. Therefore, the methods of grounding resistance reduction and parallel capacitor are adopted to strengthen the insulation capability of distribution transformer.

关 键 词：配电变压器 雷击建模 散射参数 ATP-EMTP 

分 类 号：TM421[电气工程—电器] TM86