Failure Analysis of Porcelain Bottle Rupture of a Grounding Electrode Line of a +800 kV DC Transmission Line

Taking the grounding electrode line of a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\pm 800$</tex> kV DC transmission line as the background, aiming at the unbalanced protection alarm fault of a grounding electrode line during the large load debugging of a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\pm 800\text{kV}$</tex> DC line as the research object, the treatment measures to avoid this kind of fault are put forward. Firstly, the fault process is interpreted. While analyzing the fault site, the neutral line fault waveform is analyzed. The fault reason is that the air insulation distance of the arc angle of the grounding pole tower is insufficient, resulting in discharge, which in turn causes the unbalanced protection alarm of the grounding pole line. Finally, the flashover of the 14# right phase insulator is damaged, and there are even discharge traces in many places. Finally, combined with the fault types of the grounding pole and tower in the field, it is proposed to check the hidden trouble of the arcing angle of all the tower, adjust the gap distance to a sufficient state, and strengthen the monitoring and protection of the grounding pole, and upgrade the function of the monitoring system to prevent the occurrence of such faults.