Permanent magnet motor rotor structure for compressor

Abstract

A permanent magnet motor rotor structure for a compressor comprises a rotor iron core formed by overlapping and pressing a plurality of rotor punching pieces, a permanent magnet, a rotor main shaft and a permanent magnet installation groove, and is characterized in that a permanent magnet motor rotor adopts a built-in structure, the permanent magnet is arranged in the rotor iron core and is distributed into two layers in the radial direction of a rotor iron core, the permanent magnet comprises a permanent magnet part which is arranged at the outer layer in the radial direction of the rotor iron core and has strong magnetism and a permanent magnet part which is arranged at the inner layer and has weak magnetism, the permanent magnet installation groove is correspondingly distributed into two layers in the radial direction of the rotor iron core to contain the permanent magnet in an embedding mode, and the end of the inner-layer permanent magnet installation groove in the radial direction of the rotor iron core adopts a sharp-angle structure. Through the optimization design of the inner-layer permanent magnet installation groove, the permanent magnet motor rotor structure for the compressor can obviously improve the demagnetization resistance of a motor and adopts the permanent magnet with a low grade, thereby achieving low cost of a compressor system.

Description

technical field [0001] The invention relates to a motor rotor structure, in particular to a permanent magnet motor rotor structure for a compressor. Background technique [0002] At present, due to the rising price of NdFeB permanent magnets, the cost pressure of compressors is relatively high. In order to reduce costs and improve motor efficiency, engineers and technicians have proposed many methods and measures: mainly including: using ferrite motors, reducing the grades of NdFeB permanent magnets used, etc. Ferrite permanent magnets have poor magnetic properties and low energy density, which is not conducive to the miniaturization of compressors; while simply reducing the grade of NdFeB permanent magnets will face the problem of increasing the risk of permanent magnet demagnetization under harsh working conditions. Such as figure 1 As shown, in the existing permanent magnet motor rotor structure, the magnetic bridge at the end of the two-layer permanent magnet installat...

AI Technical Summary

Problems solved by technology

Ferrite permanent magnets have poor magnetic properties and low energy density, which is not conducive to the miniaturization of compressors; while simply reducing the grade of NdFeB permanent magnets will face the problem of increased risk of permanent magnet demagnetization under harsh working conditions

like figure 1 As shown, in the existing permanent magnet motor rotor structure, the magnetic bridge at the end of the two-layer permanent magnet installation slot is generally not optimized, and is narrow, and the magnetic field lines are difficult to pass through. The armature magnetic field directly acts on the end of the permanent magnet and thus Demagnetization at the end of the inner ferrite permanent magnet with weak magnetic properties

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