Comparing the advantages and disadvantages of brushed motors and brushless motors

Sports motors can be seen everywhere in our lives, ranging from four-wheel drive vehicles played by children to ships of tens of thousands of tons, all of which have different motors working. Of course, there are various types of motors. According to different classification standards, at least dozens of different sub-categories can be derived from sports motors. For example, according to the type of working power supply, sports motors can be divided into two types: DC motors and AC motors. If it is divided according to whether there is a brush structure, it can be divided into two categories: brush motor and brushless motor. Generally speaking, there are many brush mechanisms inside the DC motor, while there is no brush structure in the AC motor. So, what are the advantages and disadvantages of each of them? Let's compare:

First of all, let’s talk about the characteristics of brushed motors. The internal structure of brushed motors is simpler than that of brushless motors, and the technology development is relatively mature. Often only the brushes need to be replaced during maintenance, and the manufacturing cost is low. At low speed starts, the brushed motor has more torque, smooth shifting and less vibration.

Of course, compared with brushless motors, brushed motors have a shorter service life, and are prone to sparks and electromagnetic interference during motion, which affects its project application and lower reliability. In addition, brushed motors have poor heat dissipation capabilities, high energy consumption, and a greater probability of problems.

In contrast, brushless motors have good heat dissipation, long life, no sparks, electromagnetic interference and other problems. They do not need regular cleaning and replacement of brushes, and are easy to maintain. Of course, its structure is relatively complicated. Once it is damaged, it needs to be replaced entirely. The manufacturing cost is high, and the vibration is relatively large when starting. It needs to reach a constant speed before it can be stable.

So should our friends who make servo systems choose brushed motors or brushless motors? It depends on your needs. If you pay more attention to manufacturing cost, then brushed motors can also be used. But if you think about it in the long run and don't want to repair the machine at every turn, the brushless equipment using permanent magnet synchronous AC motors is more worth considering.