Insulation medium of dry type transformer

In the power grid, there are autotransformer from 220kV voltage level, which is mostly used as the connecting transformer between power grids. There is almost no autotransformer below 220kV. An autotransformer is a transformer whose primary and secondary windings are in the same winding. According to the structure, it can be divided into adjustable pressure type and fixed type.



　　As for dry-type transformer, its insulation medium is resin and other solid, there is no insulating oil in oil immersed transformer, so it is called dry type transformer. Dry type transformer due to relatively poor heat dissipation conditions, so the capacity can not be large, generally as long as small and medium-sized transformers, the voltage level is 35kV and below, almost no higher than 35kV.