融冰绝缘地线对变电站雷电过电压的影响

地线直流融冰采用了全线绝缘化设计，而地线绝缘化设计将对变电站雷电过电压产生影响。以500 kV融冰绝缘地线为例，介绍了融冰绝缘地线架设方式，采用 ATP-EMTP 软件建立500 kV变电站雷电侵入波过电压模型，分析了融冰绝缘地线架设对500 kV变电站雷电过电压的影响，总结了雷击点位置、杆塔接地电阻、避雷器配置方案对变电站设备雷电过电压的影响规律。研究结果表明：融冰绝缘地线架设对变电站设备最大过电压影响很小；雷击杆塔离变电站越近，变电站高压设备产生的过电压越大；母线避雷器对变电站设备保护效果较好，雷电侵入波产生的最大过电压下降较多；杆塔接地电阻越小，变电站设备最大过电压越小。其结论对涉及融冰绝缘地线变电站具有一定的参考价值。

Analysis of the Lightning Overvoltage of Substation in Melting Ice Insulated Ground Wire System

The ground wire using full insulation design is employed in the direct current (DC) melting ice technology. But the design of insulated ground wire will affect the largest over-voltage level of electrical equipment in substation. In this paper taking the actual 500 insulated ground wire as an example, the way of erected melting ice insulated ground wire was described. The insulated ground wire simulation model of 500 kV substation was established using ATP-EMTP simulation software. The influence of erection of the melting ice ground wire of 500 kV substation lightning overvoltage was analyzed. The influences law of the lightning-point distance, tower grounding resistance and arrester configuration on the lightning overvoltage of substation equipment were summarized. The results show that the melting ice insulated ground wire has little effects on the largest overvoltage of substation equipment. The closer of the lightning point to the substation is, the greater of over-voltage of substation equipment is. The bus arresters have well protective effects on the substation equipment. The largest overvoltage of substation equipment can be declined by using the bus arresters. The overvoltage level of substation equipment can decrease with the decrease of tower grounding resistance. The results can provide a certain reference to run and design the insulated ground wire in practice.