Analysis and Countermeasure of Burnout of Electromagnetic Voltage Transformer of High Altitude Area in Western China

[摘要] 3 burning accidents of electromagnetic voltage transformer of Qinghai power grid in the southern high altitude area was introduced in this paper, and the cause of the accident was analyzed, which is due to a phase grounding line, then the other two phases voltage rising caused voltage transformer damaged; occurrence of Ferro resonance over-voltage, which resulting in serious core saturation, and the over-current caused voltage transformer damaged; due to open delta is short circuit, when the single-phase grounding fault occurred, because the voltage output of 100 V from open delta winding, a very large current is formatted, and a lot of heat is made, also led to the current in primary side very large, resulting in burning TV. In view of these three reasons, the corresponding prevention measures are put forward to ensure the normal operation of the power system.

[发布机构] State Grid of China Technology College, Jinan; 250002, China^1;Yushu Electric Power Supply Company of National Power Grid, Yushu; 815000, China^2

[效力级别] 电工学

[关键词] Core saturation;Grounding line;Large current;Normal operations;Prevention measures;Single phase grounding faults;Voltage output;Voltage transformer