BLDC motor in the“BL” means“Brushless”, is the DC motor (brush motor) in the“Brush” no. The role of the brush in a DC motor (brush motor) is to pass electricity through the commutator to the coil in the rotor. So how does a BLDC motor without a brush charge a coil in the rotor?
The original BLDC motor uses a permanent magnet to do the rotor, the rotor is no coil. Since there are no coils in the rotor, commutators and brushes for electrifying are not required. In its place is a coil that acts as a stator.
The magnetic field produced by a fixed permanent magnet in a DC motor (brush motor) is immovable and rotates by controlling the magnetic field generated inside the coil (rotor). Change the number of rotations by changing the voltage. BLDC motor's rotor is a permanent magnet that spins by changing the direction of the magnetic field generated by the surrounding coils. The rotation of the rotor is controlled by controlling the direction and size of the current to the coil.
BLDC motor uses a permanent magnet as the rotor. The brush and commutator are not required because the rotor is not energized. Control the electricity to the coil from the outside.
What are the advantages of BLDC motors?
BLDC motor stator has three coils, each coil has two wires, a total of six motor leads. In fact, because of the internal wiring, usually only three wires, but it is still said that the DC motor (brush motor) is more than one. The positive and negative electrodes of the battery do not move. How to run the BLDC motor will be explained in the second installment of this series. This time we'll focus on the benefits of BLDC motor.
The first advantage of the BLDC motor is that it is“Efficient”. It can be controlled to maintain the maximum rotary force (torque). DC motor (brush motor), the maximum torque in the rotation process can only maintain a moment, and can not always maintain the maximum value. If a DC motor (brush motor) wants the same amount of torque as a BLDC motor, it can only increase its magnet. This is why the small BLDC motor also emits a lot of power.
The second advantage, “Good control,” is related to the first. BLDC motor can get precisely what you want in terms of torque, rotation, etc. . BLDC motor can accurately feedback on the target rotation number, torque, and so on. The motor's heat and electricity consumption can be restrained by precise control. If it is battery-driven, it can extend the driving time through careful management.
In addition, there are durable, electrical noise is small, and so on. The above two points are the advantages brought by non-brush. The DC motor (brush motor) because of the brush and commutator contact between long-term use will have a loss. The contact parts also produce sparks. Especially when the gap of the commutator touches the brush, there will be a huge spark and noise. If you do not want to use the process of noise, will consider using the BLDC motor.
That's the BLDC motor for you. If you want to know more about BLDC motor, keep an eye on us or contact us directly. There will be people who can help you.