Effect of 110 kV main transformer neutral point discharge gap

In allusion to a trip accident of 110 kV transformer, some calculations of short-circuit are made, thunderbolt information system of Hubei power network is researched, and the configuration of transformer neutral point discharge gap and zinc oxide lightning arrester is looked up. After analyzing, this paper finds that the neutral point discharge gap was discharged when there was high lightning overvoltage on the neutral point caused by the lightning strike. But the arrester did not work. In this instance, discharge gap protected the insulation of main transformer neutral point. At the same time, this paper analyzes the acting qualification of neutral point discharge gap and zinc oxide lightning arrester, and it has proved that neutral point discharge gap tied in zinc oxide lightning arrester of transformer neutral point could be efficacious to protect the insulation of main transformer neutral point.