The inductor is a basic circuit element used in electrical and electronic circuits to introduce inductance. It is a passive circuit element that can store electrical energy in the form of magnetic field. A simple inductor is constructed by twisting a conductor wire of finite length in the form of a winding. In this article, I will explain all the concepts related to inductor, such as the definition of inductor, the function of inductor, the types of inductors, inductor symbol, and applications of inductors. So, let’s start with the basic definition of inductor.
What is an Inductor?
An inductor is an electronic circuit component used to introduce inductance in a circuit. It is a passive circuit component that is used to store electrical energy in the form of a magnetic field.
The most important characteristic of an inductor is that it opposes any change in the amount and direction of the circuit flowing through it. In other words, the current through an inductor cannot change suddenly.
A simple inductor is basically a coil of a conductor wire of finite length.
Function of Inductor
An inductor is a coil of a conductor wire. The primary function of an inductor is to introduce inductance in the circuit.
When an inductor is connected in a circuit, it prevents sudden changes in the amount and direction of the current.
An inductor can strengthen the magnetic effect of electric current. Hence, it is also used to produce strong magnetic fields like in an induction motor.
Construction of Inductor
An inductor is constructed by winding a conductor wire on a material called the core of the inductor. When there is no core used in the inductor construction, then it is called an air core inductor.
Hence, an inductor has two main parts namely, coil and core. The core of an inductor can be made up of any material like iron, steel, etc. The coil is made of a conductor wire like copper wire.
Types of Inductors
Depending on the type of core material, inductors can be classified into the following types:
- Air Core Inductor
- Iron Core Inductor
- Ferrite Core Inductor
Inductors can also be classified based on their inductance value as follows:
- Fixed Inductor
- Variable Inductor
Let us discuss each of these types of inductors in detail.
(1). Air Core Inductor:
The air core inductor is a simple coil of conductor wire. This type of inductor does not have any core at the center of the coil. Air core inductors are used where a low inductance value is required. The important feature of air core inductors is that they do not have core losses.
(2). Iron Core Inductor:
When the core of the inductor is made up of iron, then the inductor is called an iron core inductor.
Iron core inductors are used in applications where a high inductance value is desired. These inductors are able to handle high powers.
(3). Ferrite Core Inductor:
A ferrite core inductor is one whose core is made of ferrite materials, like Fe2O4.
The ferrite core inductors are also classified into two types namely, soft ferrite core inductor and hard ferrite core inductor. The soft ferrite core inductors are used where the reversal of magnetic polarity is desired, while the hard ferrite core inductors are used where the magnetic polarity remains constant.
(4). Fixed Inductor:
A type of inductor whose inductance cannot be changed is called a fixed inductor. It is a simple coil of a finite number of turns of a conductor wire.
(5). Variable Inductor:
A type of inductor whose inductance can be changed within a specified range is called a variable inductor.
A variable inductor has a mechanism to change its inductance. For example, the inductance can be changed by moving the core of the inductor.
Inductors in Series
We can connect multiple inductors in series to obtain a higher inductance value. In series, the inductors are connected in a straight chain, end-to-end.
The total inductance of the inductors connected in series is given by,
$$L_T=L_1+L_2+L_3+⋯+L_n$$
Here, LT is the total inductance of the series combination of inductors, and Ln is the inductance of the nth inductor in the series combination.
Inductors in Parallel
When multiple inductors are connected such that one end of all the inductors is connected to one point and the other of all the inductors is connected to another common point, then the inductors are said to be in parallel.
In a parallel combination of inductors, the number of branches is equal to the number of inductors connected in parallel. The voltage across all the inductors is the same and equal to the total supply voltage.
The total inductance of inductors connected in parallel is given by,
$$\frac{1}{L_T} =\frac{1}{L_1}+\frac{1}{L_2}+\frac{1}{L_3}+⋯+\frac{1}{L_n}$$
Applications of Inductors
As mentioned above, an inductor is a passive circuit component used to introduce inductance in a circuit. It is widely used in various electrical and electronic circuits.
Some common applications of inductors are given below:
- In tuning circuits, the inductor is used to select the desired frequency of the signal.
- The inductor is used in sensors to implement automated operations.
- The inductor is also used to store electrical energy in the form of a magnetic field for a short period.
- The inductor is used to design electromagnets.
- In electric motors, the inductor is used to convert electrical energy into mechanical energy to drive mechanical loads.
- In electric generators, the inductor is used to convert mechanical energy into electricity.
- The inductor is also used to filter unwanted signals or noise like the ripples from the output of a rectifier.
- In electronic cables, the inductor is used as a ferrite bead to reduce radio frequency interference.
Conclusion
In conclusion, an inductor is a basic circuit element used to store electrical energy in the form of a magnet. Its primary function is to introduce inductance in the circuit. A simple inductor is a coil of a conductor wire of finite length.
In this article, I have explained all the major concepts related to inductors. If you have any queries related to this topic, please let me know in the comment section.