Brushless DC motor and brushless DC motor difference

What is the difference between a brushless DC motor and a brushless DC motor? Most people probably don't know the difference between a brushed DC motor and a brushless DC motor. The following is a detailed introduction to the Hemors motor.

(1) brush DC motor

Brush DC motor adopts mechanical commutation, magnetic pole does not move, coil rotation. When the motor is working, the coil and commutator rotate, but the magnetic steel and carbon brush do not rotate. Alternating changes in the direction of coil current are accomplished by commutators and brushes that rotate with the motor.

In a brushed DC motor, the process is to arrange the two power input ends of each set of coils in turn into a ring and separate them with an insulating material to form a cylinder that is integrated with the motor shaft. A set of coils is energized by pressing two points on the upper coil power input ring cylinder from two specific fixed positions, under the action of spring pressure, through two small posts (carbon brushes) made of carbon components. When the motor rotates, different coils or different poles of the same coil are energized at different times, so that the N-S pole of the magnetic field generated by the coil and the N-S pole of the nearest permanent magnet stator have an appropriate Angle difference. Mutual repulsion creates force that drives the brush motor to rotate. The carbon electrode slides over the coil terminal like a brush on the surface of an object, hence the name carbon "brush".

(2) brushless DC motor

Brushless DC motor uses electronic commutation, coil does not move, magnetic pole rotation. A brushless DC motor uses an array of electronics to sense the pole position of a permanent magnet through a Hall element. According to this view, electronic circuits are used to switch the direction of current in the coil in time to ensure that the correct direction of magnetic force is generated to drive the motor. Eliminate the disadvantages of brush motor. It is widely used in various fields, such as the electric alarm clock for battery cars, which makes full use of these functions.

Brushless DC motor consists of motor body and driver, which is a typical mechatronics product. Because the brushless DC motor operates in a self-controlled manner, it does not add starting windings to the rotor like a heavy-duty induction motor started under variable frequency speed regulation, nor does it cause oscillations and out-of-step when the load changes suddenly.