Permanent magnet motor topological construction method based on working magnetic field harmonic orientation and motor

Patent metadata

Field	Value
Publication number	US-12068646-B2
Application number	US-202117606737-A
Country	US
Kind code	B2
Filing date	Jan 21, 2021
Priority date	Nov 9, 2020
Publication date	Aug 20, 2024
Grant date	Aug 20, 2024

Abstract

A method includes calculating an initial phase θ gv of each air gap working magnetic field B gv required to generate positive back EMF based on certain parameters of each armature harmonic v th ; generating B gv and maximizing a sum of equivalent air gap flux density amplitude B eqv of each of the air gap working magnetic fields B gv while calculating a phase θ mv and a pole arc coefficient α v corresponding to each permeance harmonic; designing a number, a position(s) and a length(s) along a circumference of modulation teeth corresponding to each of the permeance harmonics based on the phase θ mv and the pole arc coefficient α v , such that a generated permeance model is consistent with the phase θ mv of each of the permeance harmonics; and optimizing radial dimensions of modulation teeth corresponding to each of the permeance harmonics to maximize the sum of equivalent air gap flux density amplitude B eqv .

First claim

The invention claimed is:

1. A permanent magnet motor topological construction method based on a harmonic orientation of a working magnetic field, the permanent magnet motor comprising a stator wound with a winding, a permanent magnet array, a rotor, and a modulation tooth array, the method comprises:
S 1 , calculating an initial phase θ gv of each air gap working magnetic field B gv required to generate a positive back electromotive force (EMF) based on a winding coefficient k wv , an initial phase θ sv and a rotation direction sgn of each armature harmonic v th in a design target, wherein each of the air gap working magnetic fields B gv is generated by the permanent magnet array;
S 2 , with generating each of the air gap working magnetic fields B gv as a design target, calculating a phase θ mv corresponding to each permeance harmonic; and with maximizing a sum of equivalent air gap magnetic density amplitude B eqv of each of the air gap working magnetic fields B gv as a design target, calculating a pole arc coefficient α v of each of the permeance harmonics, wherein each of the permeance harmonics is generated by the modulation tooth array;
S 3 , designing a number, a position, and a length along a circumference of modulation teeth corresponding to each of the permeance harmonics based on the phase θ mv and the pole arc coefficient α v of each of the permeance harmonics, such that a generated permeance model is consistent with the phase θ mv of each of the permeance harmonics as designed in S 2 ; and
S 4 , optimizing radial dimensions of modulation teeth corresponding to each of the permeance harmonics, so as to maximize the sum of equivalent air gap magnetic density amplitude B eqv of each of the air gap working magnetic fields B gv .

2. The permanent magnet motor topological construction method based on a harmonic orientation of a working magnetic field according to claim 1 , wherein the S 3 further comprises:
designing the length along a circumference of the modulation teeth corresponding to each of the permeance harmonics based on the phase θ mv and the pole arc coefficient α v of each of the permeance harmonics; and
superimposing the modulation teeth corresponding to each of the permeance harmonics to maximize an overlap area of all modulation teeth, so as to determine the number and position of the modulation teeth corresponding to each of the permeance harmonics.

3. The permanent magnet motor topological construction method based on a harmonic orientation of a working magnetic field according to claim 2 , wherein the S 4 further comprises:
optimizing radial dimensions of modulation teeth in a non-overlap area, so as to maximize the sum of equivalent air gap flux density amplitude B eqv of each of the air gap working magnetic fields B gv .

4. The permanent magnet motor topological construction method based on a harmonic orientation of a working magnetic field according to claim 1 , wherein the S 1 includes that the initial phase θ gv is calculated based on same phase φ v of the back EMF generated by each of the air gap working magnetic fields B gv , the phase φ v of the back EMF is:

φ
v

=

{

θ

g
⁢
v

-

θ
sv

sgn
⁡

(
v
)

=
1

-

(

θ

g
⁢
v

-

θ
sv

)

+
π

sgn
⁡

(
v
)

=

-
1

wherein, sgn(v) is a rotation direction of the air gap working magnetic field B gv .

5. The permanent magnet motor topological construction method based on a harmonic orientation of a working magnetic field according to claim 1 , the method further comprises:
S 5 , optimizing the stator, such that a teeth portion of the stator is composed of two alternate sets of stator teeth portions of different widths, and the winding is wound on an outer side of the stator teeth portion that is wider.

6. The permanent magnet motor topological construction method based on a harmonic orientation of a working magnetic field according to claim 1 , wherein the winding coefficient k wv is as follows:
k wv =k yv ·k dv ·k sv
wherein k yv is a pitch coefficient, k dv is a distribution coefficient, k sv is a slotting coefficient; the rotation direction sgn is determined by a winding phase number and an armature harmonic order v.

7. The permanent magnet motor topological construction method based on a harmonic orientation of a working magnetic field according to claim 1 , wherein the number of the air gap working magnetic field B gv is one or more, forming a corresponding single-harmonic working magnetic field or multi-harmonic working magnetic field.

8. A permane

Assignees

• Univ Huazhong Science Tech

Inventors

• Li Dawei
• Fang Li
• Ren Xiang
• Qu Ronghai

Classifications

• H02K2213/03

  Machines characterised by numerical values, ranges, mathematical expressions or similar information · CPC title

• H02K1/2791

  Surface mounted magnets; Inset magnets · CPC title

• H02K1/146

  consisting of a generally annular yoke with salient poles · CPC title

• H02K29/03

  with a magnetic circuit specially adapted for avoiding torque ripples or self-starting problems · CPC title

• H02K2201/03

  Machines characterised by aspects of the air-gap between rotor and stator · CPC title