Skip to main content

What Is Rectifier?


A rectifier is an electrical device composed of one or more diodes that converts alternating current (AC) to direct current (DC). A diode is like a one-way valve that allows an electrical current to flow in only one direction. This process is called rectification.


A rectifier can take the shape of several different physical forms such as solid-state diodes, vacuum tube diodes, mercury arc valves, silicon-controlled rectifiers and various other silicon-based semiconductor switches.
Rectifiers are used in various devices, including:
  • DC power supplies
  • Radio signals or detectors
  • A source of power instead of generating current
  • High-voltage direct current power transmission systems
  • Several household appliances use power rectifiers to create power, like notebooks or laptops, video game systems and televisions.
What is a rectifier?

When the voltage is applied to the P-N junction diode in such a way that the positive terminal of the battery is connected to the p-type semiconductor and the negative terminal of the battery is connected to the n-type semiconductor, the diode is said to be forward biased.

When this forward bias voltage is applied to the P-N junction diode, a large number of free electrons(majority carriers) in the n-type semiconductor experience a repulsive force from the negative terminal of the battery similarly a large number of holes (majority carriers) in the p-type semiconductor experience a repulsive force from the positive terminal of the battery. 

There are 3 types of rectifiers:
I) Half-Wave Rectifier.
You can see in the diagram, when an AC signal is fed on the input of the transformer, the diode only allows current through it when it gets forward biased (diode in forward bias offers low resistance to the current). So, the resulting signal at the output is a pulsating DC. These type of rectifiers have a low efficiency (DC output power/AC input power) of 40.6%.
II) Centre-tapped Fullwave rectifier.
In the above circuit, let an AC signal is fed on the input. When terminal 1 is postive and terminal 2 is negative, diode D1 gets forward biased and current flows through it, but diode D2 gets reverse biased, current doesn't flow through it. Again, when terminal 1 is negative and terminal 2 is positive, diode D1 gets reverse biased and current doesn’t flow through it, but diode D2 gets forward biased and current flows through it. So the resulting output is a smooth DC signal. These rectifiers have a efficiency of 81.2%
III) Bridge Rectifier.
In the above circuit, let an AC signal is fed on the input. When terminal B is postive and terminal D is negative, diodes D1&D3 get forward biased and current flow through them, but diode D2&D4 get reverse biased, current don’t flow through them. Again, when terminal B is negative and terminal D is positive, diodes D2&D4 get forward biased and current flow through them, but diode D1&D3 get reverse biased, current don’t flow through them. So, the resulting output is a smooth DC signal. The efficiency of these type of rectifiers is 81.2%.

Labels

Labels:

Comments

Post a Comment

Popular posts from this blog

What Is Electronics Engineering?

Electronics engineering, or electronic engineering, is an electrical engineering discipline which utilizes non-linear and active electrical components (such as semiconductor devices, especially transistors, diodes and integrated circuits) to design electronic circuits, devices, microprocessors, micro controllers and other systems.  It also deals with the design and application of circuitry and equipment for power generation and distribution, machine control, and communications.   In other worlds we say that electronics engineering is an area which purely describes the study and areas of electricity, electronics and electromagnetism. Due to many amendments taken place in the field of electronics, electronics engineering has been divided into many sub categories including digital computers, power engineering, telecommunications, control system, radio frequency engineering, signal processing, microelectronics and instrumentation.Electronics engineering homework help p...
Post a Comment
Read more

What is Supercomputer

A supercomputer is a type of computer that has the architecture, resources and components to achieve massive computing power. Today's supercomputers consists of tens of thousands of processors that are able to perform billions and trillions of calculations or computations per second. Supercomputers are primarily are designed to be used in enterprises and organizations that require massive computing power. A supercomputer incorporates architectural and operational principles from parallel and grid processing, where a process is simultaneously executed on thousands of processors or is distributed among them. Although supercomputers houses thousands of processors and require substantial floor space, they contain most of the key components of a typical computer, including a processor(s), peripheral devices, connectors, an operating system and applications. As of 2013, IBM Sequoia is the fastest supercomputer to date. It has more than 98,000  processors  that allow it t...
Post a Comment
Read more

Disney's 'Magic Bench' Puts You in the Picture with Animated Figures

A new "Magic Bench" designed by Disney Research lets you interact with endearing animated characters — and no special glasses or headsets are required. Instead, the complete environment — the seat, the sitter and the cartoon humanoid animals — is mirrored on a screen opposite the bench, making it possible for others to watch the scene unfold.  How does the illusion work? A camera and sensor capture images and gather depth information about physical objects — the bench and the person — that algorithms integrate with the 3D animations, the researchers wrote in a study. Meanwhile, haptic sensors built into the bench deliver vibrations that are synchronized to animated actions on the screen, creating the illusion that the animated figures are occupying real-world space next to the user.   "Our mantra for this project was: hear a character coming, see them enter the space, and feel them sit next to you," Moshe Mahler, principal digital artist at Disney R...
Post a Comment
Read more