雷击引发主变压器重瓦斯动作分析及防范措施

Analysis and Countermeasures of Heavy Gas Action of Main Transformer Caused by Lightning Strike

为探究35kV白石变电站因雷击导致1号主变压器重瓦斯动作的原因,对1号主变压器大修和变电站防雷设施的检查、试验情况进行分析,并计算了变电站避雷针的保护范围。计算、分析认为,此次故障的主要原因是站内避雷针存在保护范围不够等问题,导致35 kV区域设备遭受雷击感应过电压。提出站内避雷针的数量由原来的2基增加至4基,和对地网和进出线接地进行改造等整改措施。

In order to find the reason of the heavy gas action of No.1 main transformer caused by lightning strike in 35 kV Baishi substation, Results of the overhaul repair of No. 1 main transformer and the check and test of lightning protection facilities in the substation are analyzed. The protection range of lightning conductors in the substation is calculated. It is found after the calculation and analysis that the main reason of the fault is the insufficient protection range of lightning conductors in the substation, which lead to devices in 35 kV range suffer the lightning induced overvohage. Countermeasures are proposed including increasing the number of lightning conductors from 2 to 4, and modifying the grounding network and the grounding of inlet and outlet lines.