What is a brushless DC motor and how does it work?

What is a brushless DC motor and how does it work?

Brushless DC motors are commonly used in medical, aviation, industrial automation, electric vehicles, and robotics applications worldwide. Simply put, you may think that brushless DC motors do not include brushes and use direct current. Compared to other types of motors, these motors have many specific advantages, but besides basic knowledge, what exactly is a brushless DC motor? How does it work and what is its function?

Working principle of brushless DC motor
It usually helps explain the working principle of brushed DC motors, as they have been used for a long time before brushless DC motors are available. A brushed DC motor has permanent magnets on the outside of its structure and a rotating armature on the inside. The permanent magnet fixed on the outside is called a stator. The armature that rotates and contains an electromagnet is called a rotor.

In a brushed DC motor, when current flows to the armature, the rotor rotates 180 degrees. In order to move forward further, the magnetic poles of the electromagnet must be flipped. When the rotor rotates, the brushes come into contact with the stator, flipping the magnetic field and causing the rotor to rotate 360 degrees.

Brushless DC motors actually flip from the inside out, eliminating the need for electric brushes to flip electromagnetic fields. In a brushless DC motor, the permanent magnet is located on the rotor, while the electromagnet is located on the stator. Then, the computer will charge the electromagnet in the stator, causing the rotor to rotate 360 degrees.

What are the uses of brushless DC motors?

The efficiency of brushless DC motors is usually 85-90%, while the efficiency of brushed motors is usually only 75-80%. Electric brushes will eventually wear out, sometimes causing dangerous sparks, thereby limiting the service life of electric brush motors. Brushless DC motors are quiet, lightweight, and have a longer service life. Due to the computer-controlled current, brushless DC motors can achieve more precise motion control.

Due to all these advantages, brushless DC motors are commonly used in modern equipment that requires low noise and low heat, especially in devices that operate continuously. This may include medical surgical tools, aviation, industrial automation equipment, electric vehicles, robots, and washing machines, air conditioning, and other consumer electronics products.

Compared with other types of motors, brushless DC motors have several obvious advantages, which is why they have entered numerous application fields and may gradually become mainstream in the motor market.

What is a DC brushless motor? How does it work? Provide a brief description. If you have similar motor applications, you can consult our brushless motor specification table for selection.