Inductors store energy in a magnetic field when current flows through it.
A typical inductor uses insulated wire wrapped into a coil around a central core.
As useful as inductors are, the biggest problem is their physical size.
demarco-media / Getty Images
Inductors often dwarf other electronic components in acircuitand add weight as well.
Some techniques simulate a large inductor in a circuit.
However, the added complexity and additional components limit where these techniques are used.
Harley-Davidson Archives
Filters
Inductors are used extensively with capacitors andresistorsto create filters for analog circuits and in signal processing.
By combiningcapacitors, inductors, and resistors, advanced filter topologies support a variety of applications.
Sensors
Contact-less sensors are prized for their reliability and ease of operation.
Inductors sense magnetic fields or the presence of magnetically permeable material from a distance.
These sensors work exceptionally well for cars and trucks.
Inductive sensors are limited in two major ways.
These parameters limit the applications of inductive sensors and influence the designs that use them.
Transformers
Combining inductors that have a shared magnetic path forms a transformer.
The transformer is a fundamental component of national electrical grids.
Transformers are found in many power supplies, to increase or decrease voltages to the desired level.
The gray canisters often found on the top of utility poles contain transformers.
As the frequency of the input increases, the impedance of the inductor limits the effectiveness of a transformer.
Practically, inductance-based transformers are limited to tens of kHz, usually lower.
The benefit of ahigher operating frequencyis a smaller and lighter-weight transformer that delivers the same load.
Inductive motors leverage the magnetic force applied to inductors to turn electrical energy into mechanical energy.
Inductive motors are designed so that a rotating magnetic field is created in time with an AC input.
Many simple electric motors that you’ll encounter, like those in fans, are inductive motors.
Energy Storage
Like capacitors, inductors store energy.
