How long does a brushless motor last?
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How long does a brushless motor last?

Views:0     Author:Site Editor     Publish Time: 2021-06-10      Origin:Site

If you are looking for a motor with a long service life, consider using a brushless motor. The life of a brushed motor is limited by the type of brush, which can reach 1,000 to 3,000 hours on average, while the average life of a brushless motor can reach tens of thousands of hours, because there is no brush to wear.

This passage is going to talk about the followings of brushless motor:

(1) Introduction to brushless motor

(2) The advantages of brushless motor

(3) Should I choose a brushless motor?


(1) Introduction to brushless motor

There is no such thing as a brushless direct current (BLDC) motor. Rotating electric machines generate torque in one of two ways-magnetic field alignment and reluctance (convexity). In either case, a rotating magnetic field is required. In a brushless motor, this is generated by the alternating current in the stator. Therefore, any brushless motor is actually an AC motor... there is actually no brushless DC motor!

The term BLDC motor is derived from the fact that when the electronic controller drives (commutation) the motor, when viewed from the controller's DC terminal, the system behaves like a traditional brushed DC motor-the speed is proportional to the applied DC voltage Change proportionally. Essentially, the mechanical commutator (the part that uses the brush) is replaced by an electronic controller with a power transistor. There are many ways to modulate these transistors, the most common and simplest method is called "trapezoidal drive" (also the lowest performance, but this is the subject of another blog). However, in all cases, the current generated by the controller and flowing through the BLDC motor stator windings is alternating current, not direct current.

brushless motor 

(2) The advantages of brushless motor

Compared with traditional brushed motors, brushless motors have huge advantages-it is obvious that there are no brushes that will wear out-and the speed, efficiency, weight, size and reliability have been greatly improved. The growth in the application and popularity of brushless motors has kept pace with the tremendous advances in power electronics and control technology, which is the production of "electronic commutators" (usually referred to interchangeably as: drive, controller, electronic speed controller, inverter Device, etc.).

As the world's electrification, power electronics technology, control technology and energy storage technology continue to develop, brushless motors will undoubtedly play a greater role. With the improvement of energy storage technology (especially lithium-ion batteries) and the reduction of prices, the competition between electric and hybrid electric vehicles and traditional gasoline-powered vehicles has become increasingly fierce. Electric vehicles not only use brushless motors as the main traction drive, but also use auxiliary systems, such as pumps for power steering and compressors for air conditioning, which were previously driven by engine belts. Even airplanes, such as the Boeing 787 Dreamliner, have flight-by-wire systems and electric actuators that have replaced traditional hydraulic systems and other mechanical systems, and are now becoming more and more electrified. Eventually, when the energy density of the battery is good enough, the electric propulsion may even become a practical power for the aircraft-in fact, this is already happening in the small unmanned aerial system (UAS).


(3) Should I choose a brushless motor?

In short, brushless motors are better than brushed units. Users can take advantage of reduced maintenance, improved efficiency, and reduced heat and noise. Brushless motors are synchronous units with one or more permanent magnets. Power tools with brushless motors are now considered high-end products.

The DC motor consists of two electrical parts: the stator and the rotor. When power is supplied to the motor, electromagnetic interaction will occur to make the motor move. When you reverse the direction of the voltage supplying the motor, it will rotate in the opposite direction.