Brushless DC electric motor

A brushless DC electric motor, also called an electronically commutated motor, is a synchronous motor powered from a direct-current supply. An electronic controller switches current into the motor windings so that magnetic fields effectively rotate in space and the permanent-magnet rotor follows them; the controller adjusts the phase and amplitude of the current pulses to control speed and torque. It replaces the mechanical commutator and brushes of conventional motors, and its construction is typically like a permanent-magnet synchronous motor. Compared with brushed motors it has a higher power-to-weight ratio, high speed, fast control of speed and torque, high efficiency and low maintenance. Applications range from computer disk drives and power tools to vehicles from model aircraft to automobiles, and washing machines.