BLDC Motor Low Interference

BLDC Motor Low interference

What are the advantages of brushless motors?

Less brush, brushless motor wear is mainly on the bearing, from the mechanical point of view, brushless motor is almost a maintenance-free motor, and when necessary, just do some dust maintenance can be. Brushless motor relative to the advantages of brush motor, but everything is not absolute, brush motor low-speed torque performance, torque and other performance characteristics are irreplaceable brushless motor, but the brushless motor to use the convenience With the development of brushless technology and the development of brushless technology at home and abroad with the market competition, brushless power system is high-speed development and popularization stage, which also greatly promoted the development of model movement.

Brushless motor advantages are as follows:

1, no brush, low interference

Brushless motor to remove the brush, the most direct change is that there is no brush motor running when the spark, which greatly reduces the spark on the remote control of radio interference.

2, low noise, smooth operation

Brushless motor without brush, running friction greatly reduced, running smoothly, the noise will be much lower, this advantage for the model running stability is a huge support.

3, long life, low maintenance costs

Control of Brushless DC Motor

2.1 Two-way rotation

Design Scheme of Brushless DC Motor Control

Use the full bridge circuit bidirectional rotation

Driving brushless DC motor two-way rotation, through the full bridge drive circuit to achieve the current to complete, as shown in Figure 2. The full-bridge drive circuit consists of N-channel MOSFETs. Q1 and Q4 turn on the motor when Q2 and Q3 are off. When Q1 and Q4 are off, Q2 and Q3 turn on the motor in reverse rotation.

2.2 Speed control section

The speed of the motor without load is proportional to the voltage applied to the motor. Therefore, the speed of the motor can be controlled by sampling the voltage applied to the motor. Pulse width modulation is used to generate this voltage change, as shown in Fig. Pulse width modulation is based on the duty cycle of the fixed frequency pulse width waveform. The average voltage applied to the motor is proportional to the PWM duty cycle.