The brushed silent generator motor adopts mechanical commutation, the magnetic pole does not move, and the coil rotates. When the motor is working, the coil and the commutator rotate, but the magnetic steel and the carbon brush do not rotate. The alternating change of the current direction of the coil is accomplished by the commutator and brush that rotate with the motor. The brushless motor adopts electronic commutation, the coil does not move, and the magnetic pole rotates.
The difference between the brush and the brushless speed control mode of the silent generator:
In fact, the control of the two motors is voltage regulation, but because the brushless DC adopts electronic commutation, it can only be realized with digital control, while the brushed DC is commutated through carbon brushes, using thyristors, etc. Traditional analog circuits can be controlled, which is relatively simple.
- The brushed silent generator motor has simple structure, long development time and mature technology:
As early as the 19th century, when the motor was born, the practical motor produced was the brushless form, that is, the AC squirrel-cage asynchronous motor. This motor has been widely used after the generation of alternating current. However, asynchronous motors have many insurmountable defects, so that the development of motor technology is slow.
- The DC brush motor has fast response speed and large starting torque:
The DC brush motor has fast starting response speed, large starting torque, stable speed change, almost no vibration from zero to maximum speed, and can drive a larger load when starting. The brushless motor has a large starting resistance (inductive reactance), so the power factor is small, the starting torque is relatively small, there is a humming sound when starting, accompanied by strong vibration, and the driving load is small when starting.
- The DC brush motor runs smoothly, and the starting and braking effects are good:
The brushed silent generator motor adjusts the speed through voltage regulation, so the starting and braking are stable, and the constant speed operation is also stable. Brushes motors are usually digital frequency conversion control, which first converts AC into DC, then DC into AC, and controls the speed through frequency changes, so the brushes motor runs unevenly during starting and braking, and the vibration is large, only when the speed is constant. will be stable.
- High control precision of DC brush motor:
The DC brush motor is usually used together with the reduction box and the decoder, so that the output power of the motor is larger, and the control accuracy is higher. The control accuracy can reach 0.01 mm, and the moving parts can be stopped almost anywhere. All precision machine tools are controlled by DC motors for precision.
- The DC brush motor has low cost of use and easy maintenance:
Because the DC brush motor has a simple structure, low production cost, many manufacturers, and relatively mature technology, it is widely used and very cheap. The brushless motor technology is immature, the price is high, and the scope of application is limited. It should be mainly used on constant-speed equipment, such as inverter air conditioners, refrigerators, etc., and the damage of the brushless motor can only be replaced.
- Brushless, low interference:
The brushless motor removes the brush, and the most direct change is that there is no electric spark generated when the brushed silent generator motor is running, which greatly reduces the interference of the electric spark to the remote control radio equipment.