Fault Analysis for Lightning-damaged Transformer
He Min · Zhejiang Electric Power · 2010
Through the analysis of the phenomena,detection data,damage position of the transformer short circuit fault caused by successive lightning strikes,it is found that it is mainly resulted from unreasonable winding structure and material selection,especially because the winding support is so short that it can not achieve adequate support and weakens the dynamic and thermal stability of the transformer.This paper points out that the method of transformer short-circuit impact test is different from the actual operation mode which ensures the auxiliary power.The calculation shows that the short circuit current flowing through the transformers in parallel operation is usually lower than that in independent operation.