Power electronics is the technology that acts as an interface between the electrical source and the electrical load. The electrical source is the power supply available and the load is the appliance that needs to be powered. This technology ensures that power is taken from the source to the load in the most efficient and robust way.

The power electronics interface essentially consists of a controller and a converter. The converter transforms the energy into desired form whereas the controller sets the magnitude of required voltage or current level for end-use with respect to a fixed reference value.

The power electronics components that are typically used are diodes, MOSFETs (high-frequency switches),inductors, capacitors and the like.

A typical example of power electronic equipment is the battery charger for mobile phones. Here the input AC voltage is first converted into DC voltage and then regulated to a lower DC voltage in order to charge the battery. All the conversion process is done by the battery charger which comprises of power electronic circuits. This is just one basic example of how much a role power electronics plays in our daily lives. Variable-speed drives for motors and even regulators for domestic fans are examples of power electronics applications.