Rectifiers

Most electrical power generating stations generates alternating current. The main reason for generating AC is that it could be transferred over long distances along with fewer losses than DC; however, several of the devices that are used today operate only, or more efficiently, along with DC. For instance, transistors, electron tubes, and certain electronic control devices need DC for operation.  They must be equipped with rectifier units to convert AC to DC if we are to operate these devices from ordinary AC outlet receptacles.  In sequence to accomplish this conversion people use diodes in rectifier circuits.  The reason of a rectifier circuit is to convert AC power to DC.

The most general category of solid state diode rectifier is made of silicon.  The diode acts as a gate that permits current to pass in one direction and blocks current in the other direction. A polarity of the applied voltage determines if the diode will conduct. There are two polarities that are known as forward bias and reverse bias.