How To Reduce The Noise Of The Motor?

Date: 2023-07-19     From: Longding     Author: admin

The motor noise is mainly generated by three reasons: electromagnetic, mechanical, and ventilation. How to reduce motor noise is mainly solved from these three aspects. The noise problem is also a common problem in the small and medium-sized motor industry.

Electromagnetic noise in the asynchronous motor is caused by the electromagnetic force wave generated by the interaction of the harmonic magnetic field established by the stator and rotor currents in the air gap, which causes the vibration of the core yoke to force the surrounding air to vibrate. The main reason is due to improper slot fit, rotor eccentricity, or too small an air gap.

There are many kinds of noises caused by mechanical reasons and they are also very complex. Mechanical noise is mainly caused by issues such as processing technology, processing accuracy, and assembly quality. More common is the vibration noise caused by the change in the working clearance of the bearing. The cumulative error of the axial dimension chain of the motor causes the impact between the bearing rolling body and the inner and outer raceways and excites the vibration of the motor shell to generate noise. The rotor and the shaft are not concentric or the noise is caused by poor dynamic balance of the rotor, etc. In order to further reduce the noise of the motor, it is necessary to determine the processing technology plan of the factory according to the material properties, bearing quality, and processing accuracy of the parts of the respective manufacturers.

How to reduce the noise of the motor?

1. Reduce exhaust noise. Exhaust noise is the main noise source of the unit, which is characterized by high noise levels, fast exhaust speeds, and difficult treatment. The use of a special impedance compound muffler can generally reduce the exhaust noise by 40-60 db (a).

2. Reduce the noise of the axial flow fan. When reducing the noise of the cooling fan of the generator set, two issues must be considered. One is the pressure loss allowed by the exhaust passage. The second is the required noise reduction. For the above two points, a resistive chip muffler can be selected.

3. The installation of sound-absorbing hoods is mainly used to reduce ventilation noise. In large and medium-sized motors, the muffler cover is often added to the front end of the ventilation pipe. The thickness of the lining layer of the sound-absorbing material is 50-70mm, and the sound-absorbing material is made of foam plastic or sponge, and the effect of the muffler cover is obvious.