Inductors in DC circuits

Inductors are often used to smooth out periodic variations in current. The output of a power supply will usually have remnants of the AC input on the DC output. Inductors are often used in series with the output to smooth out these variations.

The inductor as an AC blocker

Sometimes AC in one part of a circuit will leak into another part of the circuit. This is especially common in radio circuits where the frequency of the AC may be very high. Inductors are often used between these parts of the circuit to block unwanted AC from passing between them.

Summary:

• When you try to send electrical current into an inductor, the inductor tries to block the current.
• When you try to stop electrical current from flowing in an inductor, the inductor tries to keep the current going.
• If the current through an inductor is not changing, the inductor has no effect on the current.
• An inductor will impede the flow of alternating current
• An inductor stores and releases energy much like a flywheel
• An inductor acts like the opposite of a capacitor
• Inductance increases with more turns of wire
• Inductance increases with a larger diameter of coil
• Inductance increases with an iron core
• Inductance decreases with greater distance between turns