幸运农场

Home > Domain Knowledge > Content
What is a rectifier?
May 18, 2017

From Wikipedia, the free encyclopedia



A rectifier is an electrical device that   (AC), which periodically reverses direction, to (DC), which flows in only one direction. The process is known as rectification. Physically, rectifiers take a number of forms, including  , copper and selenium oxide rectifiers, and other silicon-based semiconductor switches. Historically, even synchronous electromechanical switches and motors have been used. Early radio receivers, called , used a "" of fine wire pressing on a crystal of  (lead sulfide) to serve as a point-contact rectifier or "crystal detector".

Rectifiers have many uses, but are often found serving as components of DC  and  power transmission systems. Rectification may serve in roles other than to generate direct current for use as a source of power. As noted,  of  signals serve as rectifiers. In gas heating systems  is used to detect presence of a flame.

Because of the alternating nature of the input AC sine wave, the process of rectification alone produces a DC current that, though unidirectional, consists of pulses of current. Many applications of rectifiers, such as power supplies for radio, television and computer equipment, require a steady constant DC current (as would be produced by a ). In these applications the output of the rectifier is smoothed by an (usually a ) to produce a steady current.

More complex circuitry that performs the opposite function, converting DC to AC, is called an .


Made in Zhongkai.jpg