A Transformer is an electrical device used to convert the electric voltage from smaller to larger quantities and vice versa. In other words, we can say that a transformer is a device that transfers electric energy from one alternating-current circuit to one or more other circuits. It is either used to increase (step-up) or reduce (step down) the voltage.

Following are the main applications of a transformer :

* The main task of a transformer is to step up or step down voltages.
* A transformer can be used to match impedance.
* It can be used as a rectifier.
* It acts as a voltage rectifier or stabilizer also.
* It is also used in voltmeter or ammeter applications.
* It is also used for the isolation of electrical circuits.