Sometimes due to external force conditions or improper operation, it is inevitable that the permanent magnet variable frequency air compressor will demagnetize. A permanent magnet variable frequency air compressor, its permanent magnet synchronous motor will be in the case of high current, high temperature or severe vibration. Irreversible demagnetization occurs, and the following will introduce how to solve the demagnetization problem of the air compressor.

1. Correctly choose the power of the permanent magnet motor

Demagnetization is related to the power selection of the permanent magnet motor in the variable frequency air compressor. Correct selection of the power of the permanent magnet motor can prevent or delay demagnetization. The main reason for the demagnetization of the permanent magnet synchronous motor is that the temperature is too high, and overload is the main reason for the high temperature. Therefore, a certain margin should be left when selecting the power of the permanent magnet motor. According to the actual situation of the load, generally about 20% is more appropriate.

2. Avoid heavy load starting and frequent starting

Permanent magnet motors try to avoid direct starting or frequent starting with heavy loads. In the process of asynchronous starting, the torque is oscillating, and in the valley section of the torque, the stator magnetic field demagnetizes the rotor magnetic poles. Therefore, try to avoid heavy load and frequent starting of the asynchronous permanent magnet synchronous motor of the air compressor.

3. Improved design

a. Appropriately increase the thickness of the permanent magnet From the perspective of the design and manufacture of the permanent magnet synchronous air compressor motor, the relationship between the armature reaction, electromagnetic torque and permanent magnet demagnetization should be considered. Under the combined action of the magnetic flux generated by the torque winding current and the magnetic flux generated by the radial force winding, the permanent magnets on the rotor surface are likely to cause demagnetization. When the air gap of the motor remains unchanged, the most effective way to ensure that the permanent magnet does not demagnetize is to increase the thickness of the permanent magnet appropriately.

b. There is a ventilation slot circuit inside the rotor. The important factor to reduce the temperature rise of the rotor and affect the reliability of the permanent magnet motor is the demagnetization of the permanent magnet. If the rotor temperature is too high, the permanent magnet of the variable frequency air compressor will produce irreversible demagnetization. When designing the structure, the internal ventilation circuit of the rotor can be designed to directly cool the magnetic steel. Not only reduces the temperature of the magnetic steel, but also improves the efficiency.

Air Compressor Spare Parts Supplier - Youteng

Wuxi Youteng Machinery Co., Ltd. was established in 2012, mainly engaged in air compression system, vacuum system design consulting, engineering project and repairing services etc. Our company mainly provides air compressor equipments and accessories for compressors of world-famous brands. We also support OEM. In addition, The company has a number of experienced technicians to perform maintenance work on various air compressors, dryers and filters, which have a certain influence in China. At the same time, the company also participates in motor overhaul projects and maintains various motors. We have a complete service system and sufficient spare parts to relieve customers from worries.