The Neutral Insulation Of Transformer Winding Is Briefly Described

The transformer used in the power system has two kinds of insulation structure for its neutral point: One is a fully insulated structure, which is characterized by the insulation level of the neutral point and the insulation level of the three-phase end line voltage level, this insulation structure is mainly used for small grounding current grounding system with high insulation requirements. At present, China’s 40kv and below voltage level power grids are small current grounding systems, and the transformers used are fully insulated structures. The other is the hierarchical insulation structure, which is characterized by the insulation level of the neutral point lower than the insulation level of the three-phase end outlet voltage level. The graded insulated transformer is mainly used in the high current grounding system of the 110kv and upper voltage level power grid. The transformer with graded insulation can reduce the internal insulation size, so that the size of the entire transformer can be reduced, which can reduce the cost.