Brushless DC motors were made possible by the development of solid state electronics in the 1960s. Background īrushed DC motors were invented in the 19th century and are still common. In modern washing machines, brushless DC motors have allowed replacement of rubber belts and gearboxes by a direct-drive design. Brushless motors find applications in such places as computer peripherals (disk drives, printers), hand-held power tools, and vehicles ranging from model aircraft to automobiles. The advantages of a brushless motor over brushed motors are high power-to-weight ratio, high speed, nearly instantaneous control of speed (rpm) and torque, high efficiency, and low maintenance. They may also use neodymium magnets and be outrunners (the stator is surrounded by the rotor), inrunners (the rotor is surrounded by the stator), or axial (the rotor and stator are flat and parallel). The construction of a brushless motor system is typically similar to a permanent magnet synchronous motor (PMSM), but can also be a switched reluctance motor, or an induction (asynchronous) motor.

This control system is an alternative to the mechanical commutator (brushes) used in many conventional electric motors. The controller adjusts the phase and amplitude of the DC current pulses to control the speed and torque of the motor. It uses an electronic controller to switch DC currents to the motor windings producing magnetic fields which effectively rotate in space and which the permanent magnet rotor follows. The two coils on the printed circuit board interact with six round permanent magnets in the fan assembly.Ī brushless DC electric motor, also known as an electronically commutated motor, is a synchronous motor using a direct current (DC) electric power supply.

Wire brush for drill