The device which converts AC to DC is

A rectifier is an electrical device that converts alternating current (AC). which periodically reverses direction, to direct current (DC), which flows in only one direction. The process is known as rectification. Physically, rectifiers take a number of forms, including vacuum tube diodes, mercury-arc valves9 solidstate diodes, silicon-controlled rectifiers and other silicon -based semiconductor switches, Rectifiers have many uses, but are often found serving as components of DC power supplies and high-voltage direct current power transmission systems.