CN114844311A

CN114844311A - Z-shaped rotor tooth double-stator axial magnetic field flux switching permanent magnet motor

Info

Publication number: CN114844311A
Application number: CN202210649321.9A
Authority: CN
Inventors: 张蔚; 赵建维; 徐晓斌; 钱锋; 韩向涛; 蒲云豪
Original assignee: Nantong University
Current assignee: Nantong University
Priority date: 2022-06-09
Filing date: 2022-06-09
Publication date: 2022-08-02

Abstract

The invention discloses a Z-shaped rotor tooth double-stator axial magnetic field flux switching permanent magnet motor which comprises two stators with two salient pole structures which are coaxially arranged, wherein the two stators have the same structure, a rotor is coaxially arranged between the two stators, faces the two stators and has the same air gap length; the slotting of the stator and the rotor of the traditional axial magnetic field flux switching permanent magnet motor causes the cogging torque of the motor to be larger, and the influence on the torque pulsation is particularly obvious at medium and low speeds. The axial magnetic field flux switching permanent magnet motor as a low-speed large-torque driving motor needs to inhibit cogging torque and improve running stability without reducing output torque. According to the invention, the cogging torque of the permanent magnet motor switched by the axial magnetic field flux can be effectively inhibited through the design of the Z-shaped rotor teeth, and the torque pulsation is reduced; the middle teeth of the stator magnetic conductive iron core are grooved and embedded with the auxiliary permanent magnet to form a quasi-Halbch magnetic field, so that the sine degree of air gap magnetic density is improved, the utilization rate of the permanent magnet is improved, torque pulsation is reduced, and the running efficiency of the motor is improved.

Description

Z-shaped rotor tooth double-stator axial magnetic field flux switching permanent magnet motor

Technical Field

The invention relates to a double-stator axial magnetic field flux switching permanent magnet motor, and belongs to the technical field of permanent magnet motors.

Background

Because of the advantages of high power density, high efficiency, simple structure and the like, the permanent magnet synchronous motor is rapidly widely applied to the fields of industry, aerospace and the like along with the continuous improvement of the performance of the rare earth permanent magnet material. For a permanent magnet motor, the magnetic resistance of a magnetic circuit corresponding to each pole of the motor is unbalanced due to slotting, a magnetic line generated by a magnetic field always tends to travel a path with small magnetic resistance, the magnetic line pulls a rotor to a position with the minimum magnetic resistance path, and then cogging torque is generated, and the large cogging torque affects the starting performance of the motor and the stability of output torque, so that the suppression of the cogging torque becomes a research hotspot of the permanent magnet motor.

Disclosure of Invention

The invention aims to: aiming at the prior art, the Z-shaped rotor tooth double-stator axial magnetic field flux switching permanent magnet motor is provided, and the problem that the cogging torque of the axial magnetic field flux switching motor is large is solved.

The technical scheme is as follows: a Z-shaped rotor tooth double-stator axial magnetic field flux switching permanent magnet motor comprises a first stator, a second stator and a rotor which are coaxially arranged, wherein the rotor is positioned between the first stator and the second stator;

the first stator and the second stator are identical in structure and respectively comprise E-shaped magnetic conduction iron cores and permanent magnets, the E-shaped magnetic conduction iron cores are uniformly arranged along the circumference to form a ring shape, the openings of the E-shaped magnetic conduction iron cores face the rotor, the permanent magnets are embedded between every two adjacent E-shaped magnetic conduction iron cores, and the magnetizing directions of the permanent magnets are alternately magnetized along the circumference; the middle teeth of the E-shaped magnetic conducting iron core are provided with grooves and embedded with auxiliary permanent magnets; adjacent teeth of two adjacent E-shaped magnetic conductive iron cores are wound with an armature winding together, two armature windings which are opposite along the radial direction of the stator are mutually connected in series to form a phase winding, and four armature windings on two opposite sides in the radial direction form two sets of in-phase windings;

the rotor comprises Z-shaped magnetic conduction rotor teeth and Z-shaped non-magnetic conduction rotor teeth which are sequentially and alternately arranged along the circumference, and air gaps with the same length at intervals are reserved between the rotor and the first stator and between the rotor and the second stator respectively.

Furthermore, the auxiliary permanent magnet is of a rectangular structure, is made of alnico, is magnetized in axial direction alternately, and has the same coercive force.

Furthermore, the long axes of the Z-shaped magnetic conduction rotor teeth and the Z-shaped non-magnetic conduction rotor teeth are arranged along the radial direction of the rotor, and the adjacent Z-shaped magnetic conduction rotor teeth and the Z-shaped non-magnetic conduction rotor teeth are mutually embedded together.

Has the advantages that: (1) the rotor has a simple structure, and the Z-shaped magnetic conduction rotor teeth and the Z-shaped non-magnetic conduction rotor teeth are arranged in a staggered manner, so that the rotor structure is firmer and more compact, and the running reliability of the motor is improved; compared with the traditional fan-shaped magnetic conduction rotor teeth, the Z-shaped magnetic conduction rotor teeth weaken the asymmetry of an air gap magnetic circuit between the stator and the rotor by changing the air gap magnetic conduction on two sides of the rotor, and reduce the cogging torque of the motor, and as is obvious from figure 6, compared with the fan-shaped magnetic conduction rotor teeth, the structure has smaller cogging torque.

(2) The auxiliary permanent magnet is embedded into the stator middle tooth slot, and a quasi-Halbch magnetic field is formed by the auxiliary permanent magnet and the stator permanent magnet, so that the utilization rate of the permanent magnet is improved, the air gap flux density and the sine degree are enhanced, the large output torque is favorably provided, the torque pulsation is reduced, and the efficiency is improved.

Drawings

FIG. 1 is a schematic two-dimensional structure diagram of a Z-shaped rotor tooth double-stator axial magnetic field flux switching permanent magnet motor;

FIG. 2 is a schematic view of a rotor structure;

FIG. 3 is a schematic view of a magnetically permeable rotor tooth;

FIG. 4 is a schematic view of a non-magnetically permeable rotor tooth;

FIG. 5 is a schematic diagram of an armature winding configuration;

fig. 6 is a cogging torque diagram of a Z-shaped rotor with tooth misalignment angles of 0 ° and 6 °.

Detailed Description

The invention is further explained below with reference to the drawings.

As shown in fig. 1, the Z-shaped rotor tooth double-stator axial magnetic field flux switching permanent magnet motor includes a first stator 1, a second stator 2 and a rotor 3, which are coaxially arranged, and the rotor 3 is located between the first stator and the second stator 2.

The first stator 1 and the second stator 2 are identical in structure and respectively comprise E-shaped magnetic conductive iron cores 4 and permanent magnets 5, the E-shaped magnetic conductive iron cores 4 are uniformly arranged along the circumference to form a circular ring shape, the openings of the E-shaped magnetic conductive iron cores 4 face the rotor 3, the permanent magnets 5 are embedded between every two adjacent E-shaped magnetic conductive iron cores 4, and the permanent magnets 5 are alternately magnetized along the circumference. The middle of the E-shaped magnetic conductive iron core 4 is provided with a groove and embedded with an auxiliary permanent magnet 6. The auxiliary permanent magnet 6 is of a rectangular structure, the material is alnico, the magnetizing direction is axial alternate magnetizing, and the coercive force is the same. The adjacent teeth of the two adjacent E-shaped magnetic conductive iron cores 4 are wound with an armature winding 7 together, the two armature windings 7 which are opposite along the radial direction of the stator are mutually connected in series to form a phase winding, and the four armature windings 7 on two opposite sides in the radial direction form two sets of in-phase windings;

as shown in fig. 2 to 4, the rotor 3 includes a plurality of Z-shaped magnetic conductive rotor teeth 8 and a plurality of Z-shaped non-magnetic conductive rotor teeth 9 alternately arranged along the circumference, and air gaps with the same length are respectively left between the rotor 3 and the first stator 1 and between the rotor 3 and the second stator 2. The Z-shaped magnetic conduction rotor teeth 8 and the Z-shaped non-magnetic conduction rotor teeth 9 are identical in structure, long axes of the Z-shaped magnetic conduction rotor teeth 8 and the Z-shaped non-magnetic conduction rotor teeth 9 are arranged along the radial direction of the rotor, and the adjacent Z-shaped magnetic conduction rotor teeth 8 and the Z-shaped non-magnetic conduction rotor teeth 9 are staggered and mutually embedded together to form a rotor whole.

In this embodiment, the Z-shaped rotor tooth dual-stator axial magnetic field flux switching permanent magnet motor is a dual-air-gap axial magnetic field flux switching permanent magnet motor formed by two stators and one rotor. For a three-phase motor, each stator consists of 6E-type magnetic conductive iron cores 4, 6

permanent magnets

5, 6 auxiliary

permanent magnets

6 and 6 armature windings 7. The rotor 3 is composed of 14Z-shaped magnetic conductive rotor teeth 8 and 14Z-shaped non-magnetic conductive rotor teeth 9.

As shown in fig. 5, 12 armature windings 8 are respectively wound on 12 stator permanent magnets 5 and adjacent teeth of two adjacent E-shaped magnetic cores 4 to form two sets of three-phase armature windings, and two coils which are opposite to each other in the radial direction in each set of three-phase armature windings are connected in series to form a same-phase winding. Taking the phase a winding as an example, a1 and A3 are phase a coils of the stator 1 which are opposite in the radial direction, a2 and a4 are phase a windings of the stator 2 which are opposite in the radial direction, and a1 and A3 phases are connected in series, and a2 and a4 phases are connected in series respectively to obtain two sets of phase a windings of the motor, and two sets of windings of the phase B and the phase C are obtained by the same method.

The Z-shaped rotor tooth double-stator axial magnetic field flux switching permanent magnet motor integrates the advantages of an axial magnetic field permanent magnet motor and a flux switching permanent magnet motor, and is small in axial size, high in power and torque density and high in efficiency; by adding the auxiliary permanent magnet, the sine degree of the air gap flux density is improved, and the output torque and the efficiency of the motor are improved. The E-shaped stator core has intermediate teeth, so that physical isolation among phase windings is facilitated, and good fault tolerance is achieved. The Z-shaped magnetic conduction rotor teeth and the Z-shaped non-magnetic conduction rotor teeth are uniformly distributed on the circumference and are arranged in a staggered mode to achieve the mutual positioning and fixing effects, the operation reliability of the motor is improved, and the rotor has the advantages of being simple in structure, strong in heat dissipation capacity, and convenient to assemble and produce in batches.

The foregoing is merely an example of the preferred embodiments of the present invention, and it should be understood that modifications and adaptations can be made by those skilled in the art without departing from the principle of the present invention, and that such modifications and adaptations are also considered to be within the scope of the present invention.

Claims

1. The utility model provides a two stator axial magnetic field magnetic flux switching permanent-magnet machine of Z type rotor tooth which characterized in that: the motor comprises a first stator (1), a second stator (2) and a rotor (3) which are coaxially arranged, wherein the rotor (3) is positioned between the first stator (1) and the second stator (2);

the first stator (1) and the second stator (2) are identical in structure and respectively comprise E-shaped magnetic conducting iron cores (4) and permanent magnets (5), the E-shaped magnetic conducting iron cores (4) are uniformly arranged along the circumference to form a circular ring shape, the openings of the E-shaped magnetic conducting iron cores (4) face the rotor (3), the permanent magnets (5) are embedded between every two adjacent E-shaped magnetic conducting iron cores (4), and the permanent magnets (5) are alternately magnetized along the circumference; the middle teeth of the E-shaped magnetic conducting iron core (4) are provided with grooves and embedded with auxiliary permanent magnets (6); adjacent teeth of two adjacent E-shaped magnetic conducting iron cores (4) are wound with an armature winding (7) together, two armature windings (7) which are opposite along the radial direction of the stator are mutually connected in series to form a phase winding, and four armature windings (7) on two opposite sides in the radial direction form two sets of in-phase windings;

the rotor (3) comprises Z-shaped magnetic conduction rotor teeth (8) and Z-shaped non-magnetic conduction rotor teeth (9) which are sequentially and alternately arranged along the circumference, and air gaps with the same length at intervals are reserved between the rotor (3) and the first stator (1) and the second stator (2) respectively.

2. The Z-shaped rotor tooth dual stator axial field flux switching permanent magnet machine of claim 1, wherein: the auxiliary permanent magnet (6) is of a rectangular structure, is made of alnico, is magnetized in axial direction alternately, and has the same coercive force.

3. The Z-shaped rotor tooth dual stator axial field flux switching permanent magnet machine of claim 1, wherein: the long shafts of the Z-shaped magnetic conduction rotor teeth (8) and the Z-shaped non-magnetic conduction rotor teeth (9) are arranged along the radial direction of the rotor, and the adjacent Z-shaped magnetic conduction rotor teeth (8) and the Z-shaped non-magnetic conduction rotor teeth (9) are mutually embedded together.