What is an inductor?

What is an inductor? Inductors or inductors are passive two-ended components that temporarily stores electrical energy in the form of a magnetic field as current passes through it, and its most important feature is that it resists the change of circuit current.

The most important feature of inductors
What is an inductor?

The most important characteristic of an inductor or inductor is that it opposes a change in circuit current.

Laws of physics for magnetic induction

Let’s read the theory together for a while and then move on to the more common ones, and of course, if you like, skip these things and go a little lower than the appearance of the coils.

Faraday’s law of electromagnetic induction

According to Faraday’s law of electromagnetic induction, when the current passing through a coil changes, the magnetic field, which varies with the time it is in, creates a voltage at both ends.

Lens Law
What is an inductor?

Also, according to the law of the lens, the direction of the electric driving force (EMF) is the induction in the direction of counteracting the changes in the current it creates (i.e., if the current passing through the coil is decreasing, this force acts in a direction that Prevents the current from decreasing, and if the current is increasing, the force will be in a direction that prevents the current from increasing. This is one of the features of coils.

The appearance of a screw wire
What is an inductor?

In the image below you can see what a coil looks like.

Another feature of an inductor or coil is that it blocks and removes any AC component present in the DC signal. Sometimes the coils are wound around a core, such as a ferrite core. In this case, their appearance will be like the image below.

The next image shows the structure of an inductor, the different parts of which are marked.

Indicators of inductor
What is an inductor?

You can see the orbital symbol of different types of inductors, which vary from left to right, an inductor with air core (without core), an inductor with an iron core, an inductor with ferrite core, an inductor with the core.

Energy storage
What is an inductor?

One of the basic principles of electromagnetism is that the passage of an electric current through a coil produces a magnetic field in it that is perpendicular to the direction of the current. The field is proportional to the growing current to a certain point and then stabilizes, which means that the inductance of the inductor no longer changes. If the current is stopped, the corresponding magnetic field gradually decreases to zero. That is, magnetic energy is converted back into electrical energy. This is why we say that the energy stored in the coil is temporary.

How the coil works
What is an inductor?

According to the principles of electromagnetic induction, each variable electric current passing through a coil creates a magnetic field around it whose lines are perpendicular to the direction of current flow. At the same time, each variable magnetic field induces a current in the winding in its field so that the direction of this current is perpendicular to the lines of the field. Therefore, if we consider an inductor made of conductive winding when some current passes through this inductor, it creates a magnetic field perpendicular to itself in the inductor. In the image below, you can see the inductor, the direction of the current, and the created field.

So now we have a time-varying magnetic field that produces a current in the coil, but the direction of this current is opposite to the direction of the main current that creates the field. If we call the produced current I’m or inductive current, it means the current produced by the magnetic field, and the magnetic field is also β. In the image below, you can see a summary of the events described.

The intensity of the induced current increases with the changes in the magnetic field. The magnetic field also receives energy in proportion to the change in the frequency of the input source. Thus, the higher the input current of the ac current, the higher the induced current will be in opposition to the variable generator. That is, the induced current tries to stop the ac component at a high-frequency current that wants to pass through the coil, which in a way means blocking or eliminating it.

Estimated study time
5 minutes

Source: Emelec