Store energy in a magnetic field; V=L dI/dt.
An inductor stores energy ½LI² in its magnetic field with v=L di/dt, so current cannot change instantly. It acts as a short to DC and opposes AC. Inductance L=μN²A/l. Used in filters, converters and chokes.
Switching off an inductive load can create a high voltage spike.
Inductors store energy in magnetic fields and oppose changes in current, which makes them central to filters, converters and motors.
Store energy in a magnetic field; V=L dI/dt.
Inductors store energy in magnetic fields and oppose changes in current, which makes them central to filters, converters and motors.
A changing current induces a voltage that opposes the change, so the current cannot jump instantly.
Once the current is steady the induced voltage is zero, so the inductor offers no resistance apart from its winding resistance.
Typical applications include designing a choke to limit ripple in a switching power supply, storing energy for a boost converter and filtering noise on a power line with a ferrite bead.
Study "Capacitors" first (topic 16 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Unit: henry. Back EMF on switch-off. Cores raise inductance.
Switching off an inductive load can create a high voltage spike.
The next topic is "Series and parallel capacitors and inductors", which builds directly on this one.
It is classed as Beginner in Electrical Engineering (topic 17 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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