What is the difference between a brush motor and a brushless

Description

With the increasing popularity of electric bikes and the fierce competition in the market, many companies and businesses are not only making a big deal about the price and appearance of their products, but are also advertising the small details of electric bikes in general, the most common of which is the promotion of brushed and brushless motors, and the advertising of brushless motors is one of the highlights. When you see this term, you can't help but think that since there are brushless, there must be brushes, so what is the difference between brushes and brushless? Here are some answers for you.

Definition of brushed and brushless motors

Brush motor: Brush motor is a rotating motor containing a brush device that converts electrical energy into mechanical energy (motor) or mechanical energy into electrical energy (generator). The brush motor is the basis of all motors and is characterised by fast starting, timely braking, smooth speed regulation over a wide range and relatively simple control circuits.

Brushless motors: Brushless DC motors consist of a motor body and a driver, and are a typical mechatronic product. As brushless DC motors operate in a self-controlled manner, they do not have a separate starting winding on the rotor, as is the case with synchronous motors that start under heavy load with frequency regulation, nor do they produce oscillations and lost steps during sudden changes in load. The permanent magnets for brushless DC motors of small to medium capacity are now mostly made of rare earth Nd-Fe-B (Nd-Fe-B) with high magnetic energy product. As a result, the size of a rare-earth permanent magnet brushless motor is reduced by one block size compared to a three-phase asynchronous motor of the same capacity.

The difference between the two

1, brush motor motor work, the coil and commutator rotation, magnets and carbon brushes do not turn, coil current direction of alternating changes are with the motor rotation of the commutator and brush to complete. In the electric vehicle industry brushed motors are divided into high speed brushed motors and low speed brushed motors. There are many differences between brush motors and brushless motors. From the name, we can see that brush motors have carbon brushes and brushless motors do not have carbon brushes.

2, brushless DC motor consists of motor body and driver, it is a typical mechatronic product. As brushless DC motors operate in a self-controlled manner, they do not add another starting winding to the rotor like synchronous motors that start under heavy load under frequency regulation, nor do they produce oscillations and lost steps when the load changes suddenly.

3, brush motor is a traditional product, the performance is more stable.

Brushless motors are upgraded products, and their life performance is better than that of brushed motors. However, its control circuit is more complex and the ageing screening requirements for components are more stringent. Although the motor has a long life but the control circuit is prone to failure. Therefore, brushless motors are selected after strict reliability tests to ensure quality. However, with the continuous upgrading of technology several steps, brushless motor technology has become quite mature.

4, in the actual production process, due to the brushed and toothed DC motor is a high-speed motor, the gear teeth are very small, easy to wear, but the power is large, climbing ability. The brushless DC motor, on the other hand, saves the trouble of changing carbon brushes in the course of use for two or three years. However, the process of controlling brushless motors requires a very high degree of precision. Moreover, the brushless motor controller is more expensive. In contrast to the brushless DC motor, although the carbon brush has to be replaced, but the replacement of the carbon brush is very easy, and the control of the motor is simpler, the motor runs smoothly and has a high safety factor.

5, brush motor means that the motor is a DC input, control its controller only to provide it with the size of the current can be speed; and brushless motor is actually a three-phase AC motor, rely on the controller to convert DC into three-phase AC, and according to the motor in the sensor Hall element for phase change so that the motor normal operation. Directly speaking, brushless motors have a longer life than brushed motors, and start with more energy and less power, but the controller is more costly than a brushed controller. At present, all of them are brushless controllers and brushed ones have been largely eliminated. The electric car controller is the core control device used to control the start, run, in and out, speed, stop and other electronic devices of the electric car, it is like the brain of the electric car, is an important part of the electric car.