1 What is a brush motor? Working principle
Brush motor is a type of motor that uses commutators and brushes to supply current to the coil. This type of motor has coils located on the rotor (located on the rotating part of the motor).
This type of motor is very popular today on the market thanks to its low price and simple control. It is commonly used in hand drills, hand rotary tools, toys, etc.
Working principle: based on the contact mechanism between the commutator and brush to help supply power to the coil. The brush part on this type of motor is pushed by the leaf spring or coil spring to make continuous contact and slide on the surface of the commutator or the contact slip ring, maintaining the power of the rotor.
What is a brushless motor? Working principle
Brushless Direct Current (BLDC) motor is a type of motor that works based on a permanent magnetic field and a position sensor, without using a brush (brush) to help eliminate friction and reduce noise. noise for the engine to operate smoothly and save electricity.
The operating principle of the brushless motor is to determine the position of the rotor (permanent magnet motor) to control the current to the corresponding stator winding, otherwise the motor cannot change the direction of rotation and start. automatically.
Because of the principle of control based on such rotor position, BLDC motors always need a dedicated controller in combination with the hall sensor to control the motor.
2 Compare the advantages and disadvantages of 2 types of engines
| Brush motor | Brushless motor | |
| Advantages |
– Stable performance of 75-80%. – Simple structure does not need a separate controller for the motor like brushless motor. – Simple on/off with a switch – Low initial cost. |
– High efficiency 85-90%, smooth and quiet operation even at low or high speed. – Due to the excitation from the permanent magnet, it reduces copper and iron loss, and at the same time reduces energy consumption. – Can accelerate and decelerate in a short time. – Save cost on maintenance, replacement of brushes and slip rings. – Higher motor durability. |
| Defect |
– Lower engine durability. – A lot of energy is lost due to the friction between the brush and the rotor that causes winding wear. – The worn brush (carbon brush) must be replaced after a period of use. |
– Higher cost, difficult to popularize on many products. |
Should I buy a machine with a brushless motor or a brushless motor?
As mentioned above, machines equipped with brushless motors are often much more expensive, so it will cause confusion for buyers.
However, a machine with a brushless motor is always the preferred choice for those with good finances and looking for a machine with a durable motor that is suitable for continuous use with large capacity.
A machine with a brushless motor also helps users save electricity, providing high performance that a brushless motor cannot replace.
Meanwhile, brush motors are more commonly used in daily-use machines, for devices that do not have to operate with too much power, owning such a stable motor is also important. had enough.
Above is an article that explains and objectively compares brush motors and brushless motors. Hopefully from the information about the article, you will choose the product that really suits your needs!
