Abstract: In the field of household air conditioning, the number of DC-INV compressors has increased. The anatomic results of 1700 DC-INV compressors showed that 17% of them were bad demagnetization. In the case of demagnetization, 75% is accompanied by a deformation of the insulating material of the motor, which is called "high temperature demagnetization". In order to analyze the problem of "high temperature demagnetization", the phenomenon of demagnetization of high temperature demagnetization and failure of compressor is studied. Simulation, air conditioning experiments, market visits and anatomical results point to the main cause of "high temperature demagnetization". Finally, the author puts forward some measures to prevent the high temperature demagnetization of the DC-INV compressor.

Key words: DC-INV compressor, Permanent magnet, High temperature demagnetization