Brushless DC (BLDC)

The Brushless DC (BLDC) motor is also referred to as an electronically commutated motor. There are no brushes on the rotor and commutation is performed electronically at certain rotor positions. A BLDC motor is a Permanent Magnet Synchronous Motor with unique back EMF waveform that allows them to behave similarly to a brushed DC motor. BLDC motor does not directly operate off a DC voltage source. However, the basic principle of operation is similar to a DC motor.

A Brushless DC Motor has a rotor with permanent magnets and a stator with windings, A BLDC motor is essentially a DC motor turned inside out. Brushes and commutator have been eliminated and the windings are connected to the control electronics. Control electronics replace the function of the commutator and energize the proper winding, Windings are energized in a pattern which rotates around the stator, the energized stator winding leads the rotor magnet and switches just as the rotor aligns with the stator.

The Brushless DC motor is the ideal choice for applications that require high reliability, high efficiency, and high power-to-volume ratio. Generally speaking, a BLDC motor is considered to be a high performance motor that is capable of providing large amounts of torque over a vast speed range.

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