, also known as a coil or reactor, is an electrical component that stores energy in a magnetic field when electric current flows through it. Inductors are passive devices that consist of a coil of wire that is wound around a core, which can be made of a magnetic material such as iron, ferrite, or air. The magnetic field that is generated by the flow of current through the coil opposes changes in current flow, resulting in an inductance that opposes changes in voltage.
The inductance of an inductor is proportional to the number of turns in the coil and the cross-sectional area of the core and is inversely proportional to the length of the coil. The inductance of an inductor can be increased by increasing the number of turns in the coil, increasing the cross-sectional area of the core, or using a material with higher magnetic permeability for the core.
Inductors have a variety of applications in electrical and electronic systems, including:
Power supplies: Inductors are commonly used in power supplies to store energy and smooth out fluctuations in the input voltage.
Filters: Inductors are used in LC (inductive-capacitive) filters to suppress high-frequency signals and pass low-frequency signals.
Transformers: Inductors are used as the primary and secondary coils in transformers to transfer electrical energy from one circuit to another.
Resonant circuits: Inductors are used in resonant circuits to store energy and maintain oscillations at a specific frequency.
Chokes: Inductors are used as chokes to suppress high-frequency signals and limit the flow of AC current in a circuit.
Inductive coupling: Inductors are used to couple signals between two electrical circuits through magnetic coupling.
Electromagnetic interference (EMI) suppression: Inductors are used in EMI suppression filters to reduce unwanted electromagnetic emissions from electronic devices.
DC-DC converters: Inductors are used in DC-DC converters to store energy and regulate the voltage in a circuit.