What should I do if the DC motor is too noisy?

DC motor will produce some noise during operation. Micro DC motors are OK, especially large DC motors. What if there is a lot of noise?

 

Miniature DC motor

When a DC motor is energized, the air-gap magnetic field acts on the rotor core, producing a fundamental magnetic potential and a series of harmonic magnetic potentials. The interaction of the harmonic magnetic fields generates radial forces that vary in time and space. These forces act on the core of the DC motor. On the core, it causes the core to vibrate periodically in the radial direction, generating noise, which is electromagnetic noise. Low harmonic components can effectively reduce electromagnetic noise.

 

Miniature DC motor

This pole-cutting boot noise reduction method can reduce the radial electromagnetic force that causes vibration and noise, thus reducing the electromagnetic noise of DC motors. The main pole magnetic potential and armature magnetic potential exist in DC motors. In this range, the armature anti-magnetic potential at both ends of the armature is large. Using uneven air gap main pole, the angle of the lower pole tip ramp, so both sides of the pole tip of the air gap main pole gradually increase and magnetic density gradually decrease, so that the armature magnetic potential is relatively weakened, natural gas is weakened. Gap harmonic magnetic field. In addition, the skew angle design of DC motor can also greatly reduce the amplitude of the harmonic component of the electromagnetic torque.

 

DC motor

In addition to electromagnetic noise, DC motors have mechanical noise and ventilation noise. As mentioned earlier, the electromagnetic noise of a DC motor is the electromagnetic force wave generated by the interaction of the harmonic magnetic fields established by the rotor current in the air gap, which causes the core yoke to vibrate and exert a force on the surroundings. It is caused by air vibrations. The main causes are improper slot fit, rotor eccentricity or too small air gap. There are also many types of mechanical noise in DC motors, mainly due to the processing and precision of DC motors. It is common to see vibration noise caused by changes in bearing working clearance or rotor dynamic balance problems.

 

Reduce exhaust noise, fan noise, installation of muffler cover, etc. can effectively reduce DC motor noise. For more information about micro DC motor, please continue to pay attention to Tianfu Micro Motor.

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