Causes and solutions for abnormal noise of inverter-driven motor

With the continuous improvement of industrial automation level, frequency converter has become an important part of digital control technology and is widely used in drive motors in industrial production. However, in the process of using frequency converter to drive motor, many users will find that the motor will produce abnormal noise when running. On the one hand, this noise will affect the operating efficiency and working environment of the equipment, and on the other hand, it will also shorten the service life of the motor. Therefore, solving the problem of abnormal noise of frequency converter driven motor has become an urgent problem to be solved.

1. Causes of abnormal noise in inverter-driven motors

1. Unreasonable motor structure design: Unreasonable motor structure design is one of the main reasons for the high motor noise. Unreasonable motor structure design includes factors such as motor rotor imbalance, axial displacement, improper riveting of motor core, and uneven core gap.

2. Bearing failure: The quality and installation status of the bearing have a great impact on the noise and life of the motor. Wear and damage to the bearing surface or damage to the balls and raceways inside the bearing will cause the motor to produce abnormal noise.

3. Uneven motor casting: Uneven motor casting will cause the motor to be subjected to some torque and vibration, thus generating noise.

4. Motor electromagnetic noise: The motor will generate electromagnetic noise when running. This noise is mainly caused by the current and voltage in the motor coil. The higher the motor speed, the greater the electromagnetic noise.

5. Improper inverter parameter settings: The inverter is a device used to control the speed of the motor, so improper inverter parameter settings will also cause the motor to produce abnormal noise. For example, frequency jumps, output voltage waveform distortion, current distortion, etc. will affect the operation effect and noise of the motor.

2. Methods to solve abnormal noise of inverter driven motor

1. Optimize the motor structure design: To address the noise problem caused by unreasonable motor structure design, the motor structure design can be optimized to improve the motor rotor balance, axial displacement, core riveting and other issues, thereby reducing motor noise.

2. Strengthen bearing maintenance: Bearings are an important part of the motor. Strengthening the maintenance of bearings and replacing worn and damaged bearings in time can effectively reduce the noise of the motor.

3. Optimize motor castings: Uneven motor castings are one of the causes of motor noise. Therefore, the torque and vibration of the motor can be reduced by optimizing the motor castings, thereby reducing motor noise.

4. Reduce motor electromagnetic noise: Reducing motor electromagnetic noise can be done from two aspects: one is to optimize the motor coil design to reduce the changes in current and voltage; the other is to use shielding materials to shield the motor to reduce electromagnetic radiation.

5. Reasonable setting of inverter parameters: Reasonable setting of inverter parameters is one of the keys to reducing motor noise. When setting inverter parameters, it is necessary to adjust them according to the actual situation to ensure the stability and accuracy of output voltage, current, frequency and other parameters, so as to reduce motor noise.

In summary, the problem of abnormal noise in the inverter-driven motor is caused by a variety of factors. In order to solve this problem, we need to start from the motor structure design, bearing maintenance, motor castings, motor electromagnetic noise, inverter parameter settings, etc., so as to fully optimize the motor's operating effect and noise. In actual applications, we need to make adjustments based on actual conditions to ensure the stability and accuracy of the motor, thereby ensuring the normal operation and long-term stability of the equipment.