Our dc power supplies use a rectifier which converts alternating current to direct current. In this post you’ll learn, what is a rectifier, its construction, and its practical applications.
List of Contents
What is rectifier and How it works and its construction
The electrical power coming to our homes is alternating in nature. While many electronic devices require direct current (dc). The rectifier converts ac at our wall outlets to dc.
Rectifiers are often classified into two types on the basis of construction.
- Half wave rectifier (It is made of single diode)
- Full wave rectifier (It is made of two or four diodes)
How it works
A rectifier contains 1, 2, or 4 diodes. A diode itself is a two terminal device, the terminals are namely the anode (+ve) and the cathode (-ve). During its working, a diode can either be forward biased or negative biased.
The term forward biased means that +ve terminal of a battery is connected to a +ve terminal of the diode and negative of the battery to negative of the diode. During forward biasing a diode conducts the current.
Now if opposite terminals of battery and diode are joined it is reverse biased.
Now consider the application of AC source to the diode. During the positive half cycle, the diode is forward biased, it conducts the current. Whereas during the negative half cycle, it is reverse biased and it stops the flow of current. Finally, on the output, we have a pulsating dc wave whose +ve cycle is present, but there is no negative cycle. This property of the diode is used in the rectifiers and converts ac to dc.
Let’s understand the working of full wave rectifier in action:
- The electronic dc batteries in our labs contain a rectifier circuit
- Out mobile phone chargers employ a rectifier circuit
- Laptop chargers use the same
- Almost all electronic projects which require dc supply from ac utilize a rectifier bridge in their application.
While you can construct a receiver by using 4 diodes, many electronic bridges are also available for this purpose.
Also, learn about different types of diodes.