What type of motor is a brushless DC motor?

A brushless DC motor is classified as a permanent magnet DC motor. This type of motor uses permanent magnets to create a magnetic field and relies on electronic controllers to switch the current in the motor windings, eliminating the need for brushes that are common in traditional DC motors.

The absence of brushes in brushless DC motors leads to less mechanical wear and tear, increased efficiency, and improved reliability. In this design, the rotor is typically a permanent magnet that spins within a stationary set of windings. The electronic commutation system controls the timing of the current in the windings, replacing the function of brushes and providing advantages such as a longer lifespan and reduced maintenance requirements.

Additionally, the other types of motors mentioned do not fit the specific characteristics of a brushless DC motor. For instance, AC motors with brushes would not be classified as brushless, and universal motors, while versatile, are generally designed to operate on either AC or DC with brushes. Induction motors utilize different principles altogether, where the magnetic field is created in the stator and induces current in the rotor without permanent magnets. Thus, the classification of brushless DC motors as permanent magnet DC motors accurately reflects their operational characteristics and design.