According to different classification methods, it can be divided into the following:

According to the cooling mode, they are dry (self-cooling) transformer, oil-immersed (self-cooling) transformer and fluoride (evaporative cooling) transformer.

Classified according to moisture-proof mode: open transformer, encapsulated transformer and sealed transformer.

According to the structure of core or coil: core transformer (insert core, C core, ferrite core), shell transformer (insert core, C core, ferrite core), ring transformer, metal foil transformer.

According to the number of power supply phases: single-phase transformer, three-phase transformer, multi-phase transformer.

Classified by use: power transformer, voltage regulating transformer, audio transformer, intermediate frequency transformer, high frequency transformer, pulse transformer.