Rotor punching sheet for permanent magnet motor and rotor

Abstract

The invention discloses a rotor punching sheet for a permanent magnet motor and a rotor which is formed by a plurality of the rotor punching sheets being pressed in an overlapping mode. The rotor sheet for the permanent magnet motor comprises a plurality of magnetic steel grooves which are the same. Each magnetic steel groove comprises an axial groove which is formed along the axial direction of the rotor punching sheet and a horizontal groove which is vertical to the axial groove, an end portion of each axial groove is connected and communicated with the middle portion of a horizontal groove, a connecting portion is arranged inside each axial groove along the axial direction of the rotor punching sheet, each connecting portion penetrates through each axial groove to divide each magnetic steel groove into two L-shaped auxiliary magnetic steel grooves, and the axial part of each L-shaped auxiliary magnetic steel groove is communicated with the horizontal part of each L-shaped auxiliary magnetic steel groove. Through the method of changing the shapes of the magnetic steel grooves, the number of magnetism insulating bridges is reduced, useless magnetic flux leakage is lowered, the phenomenon that use ratio of permanent magnet materials is low due to the fact that flow of magnetic flux leakage of a permanent magnet is large is avoided, and mechanical strength of the rotor punching sheet is also improved through groove division processing of the magnetic steel grooves.

Description

technical field [0001] The invention belongs to the technical field of motors, in particular to a rotor punch and a rotor for permanent magnet motors. Background technique [0002] Asynchronous start permanent magnet synchronous motor usually adopts built-in rotor structure. In the built-in rotor structure, the permanent magnet is located in the magnetic steel groove opened in the iron core. Usually, the reluctance of the quadrature axis is smaller than the reluctance of the direct axis. Moment density; the cage-shaped rotor directly faces the air gap, and the starting performance is good. The disadvantage of the built-in structure is: since the permanent magnet is inside the rotor, the magnetic flux leakage is large, and the utilization rate of the permanent magnet is low. Corresponding magnetic isolation measures must be taken to limit the magnetic flux leakage. The commonly used magnetic isolation measure is to set a magnetic isolation bridge between the magnetic steel ...

AI Technical Summary

Problems solved by technology

The disadvantage of the built-in structure is: because the permanent magnet is inside the rotor, the magnetic flux leakage is large, and the utilization rate of the permanent magnet is low. Corresponding magnetic isolation measures must be taken to limit the magnetic flux leakage

The disadvantage of this shape of the rotor punch is that since there is a magnetic isolation bridge 21 in each "L" shaped sub magnetic steel slot, and there is also a magnetic isolation bridge 22 between two adjacent transverse slots 26, due to Excessive magnetic isolation bridges cause magnetic flux leakage and low utilization rate of permanent magnetic materials

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