How Inductors Work ?

Most people have at least a basic knowledge of the conduction concept in electricity. Electrons move through some materials more easily than through others. These materials are called conductors. But what is induction? How does this differ from the process of conducting electricity?

An inductor is considered “passive” in the field of electricity that is designed to store energy “in a magnetic field created by the electric current passing through it.” (Wikipedia) In its usual form, an inductor is made of wire in a coil. This helps create the magnetic field. Definitions of what inductors do often include the tasks of delaying and reshaping currents.

Inductance is measure in “henries.” A law named for inventor and electrical researcher Michael Faraday refers to the electromotive force that “opposes this change in current.” Differences in how the inductors work come from the number of “loops” made in the coil, the size of the “loops” what material is used to construct the coil and its core.

Inductors are also distinguished as “ideal” and “real.” The first of these has inductance but is not a resistor or capacitor. It does not radiate electrical energy. In contrast, the “real” inductor is a combination element in an electrical system. In addition to its inductance task, this type of inductor provides resistance because of the wires inherent ability to resist. A “real” inductor also has some capacitance. That is, it can collect and dissipate electrical energy in a way similar to a true capacitor.

It’s interesting to note two other elements of inductor operation. Losses in the core around which the wire is wound can contribute to inductor losses, especially in the presence of high frequencies. Inductors may also function as antennae, “radiating a part of energy processed into surrounding space and circuits.”

Inductors have been used for years in analog circuits, as well as for processing communication signals. The combined use of inductors and capacitors can filter certain frequencies. This is a primary use for preventing interference in radio applications and in tuning circuits. They are a key element in power supplies as well. Using two, three or more inductors can provide the necessary effect without the size and weight of one very large inductor.

Academic texts and educational materials also show inductors used as storage elements in certain power-supply applications. In this case the inductor is in the energized state for only a part of the frequency cycle.

A primary use of the inductance concept is the reactor. The inductor may be installed in a larger electrical system to help reduce voltage or hold voltage that might enter the system from lightning or another large surge. To put this idea in the simplest terms, inductors store electrical energy but differ from capacitors and other elements in that they generally don’t dissipate or distribute energy in the same way.

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