ABSTRACT
In the most basic definition, a transformer is a device that magnetically links two or more circuits for time-varying voltage and current. Magnetic coupling has a number of intrinsic advantages, including (1) DC isolation between the circuits, (2) the ability to match the voltage and current capability of a source to a load on the other side, (3) the ability to change the magnitude of the voltage and current from one side of the transformer to the other, and (4) the ability to change the phases of voltage and current from one side of the transformer to the other (three phase).
