How Do Brushless Motors Work?

Brushless DC motors have recently become commonplace in consumer electronics. They are found in vacuum cleaners, refrigerators, cooling fans and washing machines in many other types of equipment. From the existence of more and moreĀ dental brushless micro motor suppliers, they are even widely used in dentistry.


Brushless motor are a type of motors that rely on electronic controlled commutation as opposed to brushes. Their rotors consist of permanent magnets and their stators consist of multiphase armature windings. So how does a brushless motor work?

The brushless DC motor consists of three different components; a computer/electronic driver, an electromagnet and a permanent magnet. To create motion, the magnetic field generated by the permanent magnets interacts with the magnetic field induced in the electromagnet through the current through the stator to produce mechanical torque. The computer or, more specifically, the electronic switching circuit switches the power supply to the stator to maintain a constant angle of 0 to 90 degrees between the two fields. Hall sensors are used to sense the position of the rotor based on the north or south pole. Hall sensors are mounted on the stator or on the rotor to produce high or low signals. The windings are energized based on a combination of the generated signals. In order to maintain motion and keep the motor running, the magnetic field induced in the winding should move in position as the motor moves to keep up with the stator magnetic field.

The brushless DC motors can be controlled using dedicated microcontrollers, PLC units, hard-wired microelectronic units or any other similar unit. These controls enable people to implement complex controls such as vector control, high speed control and field oriented control. Analog controllers can also be used, but it’s important to note that they don’t handle feedback.

There are plenty different kinds of dental brushless micro motor here atĀ, you can have a look if you are interested in.


Leave a Reply