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How does a brushed DC motor work?

Around 1830-1840, DC motors were invented. However, it was not successful in terms of commercialization. These motors were originally battery powered. Around the middle of the 1800s, low-quality batteries and high costs resulted in no real market. However, at the end of this era, due to the emergence of transmission networks and rechargeable batteries, DC motors for commercial use began to appear on the market.

The impact of this is that the performance of brushed DC motors continues to improve and is still widely used. However, other motors have also begun to appear quietly, such as brushless DC motors and induction motors. Nowadays, such brushed motors are restricted in several usage scenarios.

Features of brushed DC motors:
Like every motor, a brushed DC motor consists of two main parts: the rotor and the stator. On the stator, either the exterior contains permanent magnets (PMDC) or electromagnetic coils (SWDC). Inside, the rotor or "armature" is in it.

The rotor contains a coil powered by a direct current. With DC power supply, the magnetic field begins to appear around the rotor. The reason for the rotation is that part of the rotor is attracted by the magnetic field of the stator. The other part has already been rejected.
The continuous rotation is due to the existence of the rectifier. Basically, the rectifier manages the direction of the current and the direction of the magnetic field. Due to attraction and repulsion, the rotor starts to turn and align horizontally, and all the brushes will be connected to the reverse side of the rectifier.

In this way, the current through the rotor starts to reverse. As a result, the magnetic field also starts to reverse. As long as current is supplied to the DC motor, the whole process will continue.

Different types of brushed DC motors:
1. Permanent Magnet DC motor
2. Series motor
3. Shunt motor
4. Compound motor

Advantages of brushed DC motors:
Brushed DC motor is a motor that is easy to understand and has a simple and cheap drive design. Basically, for a DC series motor, under a given load, there is a linear relationship between the supplied voltage and the speed.
The higher the voltage, the higher the speed. This means that speed and torque can be easily controlled by voltage. At the same time, that is to say, it does not require electronic products to control the load. Finally, the DC motor allows rapid start and stop acceleration.

Disadvantages of brushed DC motors:
The main disadvantage of brushed DC motors is the presence of brushes. These things are damaged relatively quickly, so this will lead to high maintenance costs. In addition, the motor cannot be operated in a dangerous environment.
In addition, due to the presence of the brush, it can cause the appearance of sparks. Furthermore, although the speed and torque can be controlled by changing the voltage. However, this control is not precise. Therefore, in scenarios requiring high-precision control, additional complex electronics need to be used.

Application scenarios of DC motors:
It is determined by the type of DC motor. Generally speaking, the following scenarios are universal: cranes, conveyor belts, pumps, fans, machine tools, air compression equipment, toys, car starters, etc.