How Electric Motors Work

Electric Motor Basics

Due to the significant differences in electric motor designs, I will first explain the basic principle that electric motors utilize — electromagnetism. All electric motors, (whether linear or rotary) generate a magnetic field using windings. Each of these motor windings is a coil of copper or aluminium wire (usually copper) wrapped around an iron core. The iron core is a piece of iron (often assembled by stacking iron plates on top of one another).

The electromagnetic field generated is concentrated (mostly, at least) inside the iron core, turning the iron core into an electromagnet. This serves exactly the same purpose as any permanent magnet, so why must electricity be consumed to generate this magnetic field?

Note: A permanent magnet is an object which remains magnetic without a power source. 

This is because electric motors require varying magnetic fields to operate. They also need the ability to switch on and off as needed. The primary variation I mentioned is magnetic field reversal. The magnetic field is switched on to turn the rotor a little, then reverse to push it a little further. This magnetic pole reversal happens many times per second, which is why it doesn’t look tedious or rough as I made it sound.

It’s actually a silky smooth process! The most common electric appliance motors contain an armature with three windings in it. Each motor winding (identical to what I mentioned above) is wrapped around piece of iron which is attached to a central iron core.

How Brushless Motors Work

Brushless electric motors operate so smoothly and efficiently because they don’t rely on brushes. Brushless motors work almost the same way as brushed motors, minus the brushes and commutator.

How Brushless DC Motors Work

A semiconductor-powered device called a controller alternates their magnetic fields. These controllers are more expensive than brushes, but they last longer. Brushless DC motors are also considerably more efficient, smoother, and quieter than their raucous brushed counterparts.