A transformer is an apparatus for converting electrical power in an ac system at one voltage or current into electrical power at some other voltage or current without the use of rotating parts. Transformers have been an essential component in electrical as well as electronic circuits. Apart from stepping up or stepping down the voltages, they are used for providing isolation, for impedance mismatch and so on. Development of new technologies has reduced the usage of transformers, but still they are quite vital in many applications.