What is an inductor

Release time: 2023-07-20

An inductor (Inductor) is a component that converts electrical energy into magnetic energy and stores it. The structure of an inductor is similar to a transformer, but with only one winding. An inductor has a certain inductance, which only hinders the change of current. If the inductor is in a state where no current is passing through, it will try to prevent current from flowing through it when the circuit is turned on; if the inductor is in a state where current is passing through, it will try to maintain the current when the circuit is turned off. Inductors are also called chokes, reactors, and dynamic reactors.

inductors are generally composed of a skeleton, a winding, a shield, a packaging material, a magnetic core or an iron core, etc.

1. Skeleton skeleton refers to the bracket for winding coils. Some of the larger fixed inductor or adjustable inductor (such as oscillation coil, choke coil, etc.), most of the enameled wire (or yarn) around the skeleton, and then the magnetic core or copper core, iron core, etc. into the inner cavity of the skeleton, in order to improve its inductance. The skeleton is usually made of plastic, bakelite and ceramic, and can be made into different shapes according to actual needs. Small inductors (such as color code inductors) generally do not use the skeleton, but directly around the core of the enameled wire. Air-core inductors (also known as coil-free or air-core coils, mostly used in high-frequency circuits) do not use magnetic cores, skeletons, shielding covers, etc., but are wound on the mold before taking off the mold, and pull a certain distance between the coils.

2. Winding A winding refers to a set of coils with a specified function, which is the basic component of an inductor. There are single-layer and multi-layer windings. Single-layer winding also has two forms: close winding (when winding, the wires are wound one by one) and inter-winding (when winding, each turn of the wires is separated by a certain distance). Multi-layer winding includes layered flat winding, random winding, honeycomb winding, etc.

3, magnetic core and magnetic rod magnetic core and magnetic rod are generally made of nickel-zinc ferrite (NX series) or manganese-zinc ferrite (MX series) and other materials, which have "I" shape, column shape, hat shape, "E" shape, tank shape and other shapes.

4, iron core materials mainly include silicon steel sheet, permalloy, etc., and its shape is mostly "E" type.

5. In order to prevent the magnetic field generated by some inductors from affecting the normal operation of other circuits and components, a metal screen cover (such as the oscillation coil of semiconductor radio, etc.) is added to the shielding cover. The inductor using the shield will increase the loss of the coil and reduce the Q value.

6. Packaging Materials After some inductors (such as color code inductors, color ring inductors, etc.) are wound, the coils and magnetic cores are sealed with packaging materials. The packaging material is plastic or epoxy resin.