BLDC Vs. PMDC0 pages

Brushless DC

Brushed DC

CONSTRUCTION
CONSTRUCTION
FEATURES / PERFORMANCE
FEATURES / PERFORMANCE

Rotor

Permanent magnet on rotor

Winding on rotor/armature

Stator

Windings on the stator

Permanent magnet on stator

Controller

Electric controller is required

No controller is required

Torque

Suitable for high torque applications

Suitable for low torque applications

Speed

Higher speed range due to no
mechanical limitation imposed by
brushes/commutator
Typical life expectancy 10,000 to
20,000 hours

Lower speed range due to mechanical
limitations on the brushes

Life

BENEFITS / COMPARISON
BENEFITS / COMPARISON

Efficiency

High efficiency up to 90%

Typical life expectancy is 2000 to 5000
hours depending on the application and
duty cycle
Typically 60-70% efficiency

Commutation Method

Electronic commutation requiring a
driver/controller

Uses mechanical commutator to reverse
the polarity of the armature electromagnet

Maintenance

Brushless design requires little to no
maintenance

Heat Dissipation

Superior thermal characteristics
results in better heat dissipation

Periodic maintenance is required; can
replace brushes for extended life if
necessary
Internal rotor construction results in
limited heat dissipation

Noise

Low electric noise generation

Brushes emit audible nose during rotation

Cost

Higher manufacturing cost

Lower manufacturing cost

Operation environment

More suitable for normal controlled
environments
Fuel Controls, missile fin actuators,
dental tools, respirators, R/C model
airplanes, pumps, robotics, electric
and hybrid vehicles, medical
equipment, lawn mowers, factory
automation, and gate operators

Can operate in more extreme
environments due to the lack of electronics
Printers, toys, semiconductor equipment,
packaging machines, automotive motors,
wheelchairs, medical equipment, electric
toothbrushes, vacuum cleaners, hair
dryers, drill screwdrivers and gate
operators

Applications