How Electric Motors Work

Electric motor diagram showing magnetic field, coil, and commutator
Introduction

What is a Motor?

An electric motor converts electrical energy into mechanical energy, usually as rotational motion. There are two types of electric motors based on the type of current they use, the coil design, and the magnetic field created.

DC motor cross-section showing rotor, stator windings, and hall sensors
DC Motors

Direct Current Motors

The DC motor works by direct current flowing to the commutator, which is connected to the electromagnets. The electromagnets rotate as the polarity changes due to the current and are surrounded by permanent magnets.

  • Rotation driven by continuous current-direction switching
  • Commutator and brushes manage current reversal
  • Hall sensors used in brushless variants

DC motors are of two types: brushed motor and brushless motor.

Brushed motors have brushes that are connected to the current. These brushes stay in contact with the rotating part (armature).

In brushless motors, a sensor is needed to determine the orientation of the rotating motor poles. It also needs a driver to supply current.