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Brushed DC motors may seem less glamorous than their brushless cousins but they deliver reliable, proven performance that needs less complicated drive circuitry – keeping overall costs to a minimum.

Choosing the right motor for any given application depends on the specific requirements of that application. Is precise control of the motor’s position required, with the smoothness of motion offered by brushless motors, or can a simpler, lower cost brushed alternative provide a better solution? Is it important to avoid wear and maintenance, which a brushless motor can deliver, or does the application’s motor operate so rarely that deterioration of the brushes and commutator is a low priority?

If the application does not justify the higher cost and complexity that come with the features offered by a brushless motor, then a brushed DC motor, coupled with the right drive circuit design, can still provide a very appealing solution.

The key differences between a DC brushed motor and a DC brushless motor are:

Commutation: DC brushed motor uses brushes to deliver current to the motor windings through mechanical commutation, whereas DC brushless motor uses electrical commutation to deliver the current.
Speed range: DC brushed motor has a lower speed range compared to DC brushless motor, which has a high speed range due to the absence of brushes and commutator.
Control: DC brushed motor has simple control, whereas DC brushless motor has complex and expensive control due to the need for electronic commutation.
Electrical noise: DC brushed motor generates arcs in the brushes, which produce noise, whereas DC brushless motor has low electrical noise.
Rotor inertia: DC brushed motor has higher rotor inertia, which limits its dynamic characteristics, whereas DC brushless motor has low rotor inertia due to the permanent magnets on the rotor, which increases its dynamic response.
Maintenance: DC brushed motor requires periodic maintenance, whereas DC brushless motor requires less maintenance due to the absence of brushes.
Speed/torque characteristics: DC brushed motor has low mechanical limitations by brushes, whereas DC brushless motor has no mechanical limitations.
Efficiency: DC brushed motor has moderate efficiency, whereas DC brushless motor has high efficiency.
Life: DC brushed motor has a shorter life due to brush wear and tear, whereas DC brushless motor has a longer life due to the absence of brushes.
Building cost: DC brushed motor is lower in cost compared to DC brushless motor, which is higher due to the use of permanent magnets.
Control requirements: DC brushed motor does not require a controller, whereas DC brushless motor always requires a controller to keep the motor running.
Construction: DC brushed motor has armature winding on the rotor and fixed magnets on either side of the rotating electromagnet, whereas DC brushless motor has armature winding on the stator and fixed magnets on the rotor.
Applications: DC brushed motor is used in home appliances, kid toys, industrial applications, medical equipment, robots, and drones, whereas DC brushless motor is used in electric vehicles, hybrid vehicles, electric bicycles, industrial applications, drones, washing machines, fans, pumps, and blowers. 2 years, 1 month ago