dc brushless motor consists of a permanent magnet rotor and a multi-phase armature winding. It differs from a conventional DC motor in that it does not include a brush, the commutation is done by electricity, and an electronic driver is used to power the stator windings.
Basically, dc brushless motors are constructed in two ways – one to place the rotor outside the core and the other to place the windings outside the core. In the former arrangement, the rotor magnet acts as an insulator, reducing the heat dissipation rate of the motor and operating at low currents.In the latter arrangement, the motor dissipates more heat, thereby increasing its torque.
dc brushless motor is driven by an electronic driver that switches the supply voltage between the stator windings as the rotor rotates. The rotor position is monitored by a transducer (optical or magnetic) that provides information to the electronic controller and determines the stator windings that need to be energized based on the position.
dc brushless motor uses a fixed permanent magnet and rotates the armature to eliminate the problem of connecting current to the moving armature.
The cost of the dc brushless motor has declined since its presentation, because of progressions in materials and design. This decrease in cost, coupled with the numerous focal points it has over the Brush DC Motor, makes the dc brushless motor a popular component in numerous distinctive applications.