Some different types of transformers include:
1) Power transformer – this is used for transmission & distribution of electrical power.
2) Autotransformers – converting voltage within relatively small limits to connect power system of different voltage, to start A.C motors etc.
3) Transformer for feeding installations with static converters. (mercury arc rectifiers ), ignitrons, semi-conductor valves etc.) – this is used for converting A.C into D.C (rectifying) and converting D.C into A.C (inverting)
4) Testing transformers- use for conducting the test at high and ultra-high voltage.
5) Power transformers for special applications – it is used for Furnace, welding etc.
6) Ratio transformers- it is used for Ratio engineering etc.