CN111064341B

CN111064341B - Six-unit permanent magnet linear motor

Info

Publication number: CN111064341B
Application number: CN202010039690.7A
Authority: CN
Inventors: 曾德鹏; 李晓旭; 游江; 王琨
Original assignee: Harbin Engineering University
Current assignee: Harbin Engineering University
Priority date: 2020-01-15
Filing date: 2020-01-15
Publication date: 2021-12-21
Anticipated expiration: 2040-01-15
Also published as: CN111064341A

Abstract

The invention discloses a six-unit permanent magnet linear motor, wherein a stator part comprises a hexagonal prism stator, six side surfaces of the hexagonal prism stator are respectively provided with a groove, and permanent magnets are respectively arranged in the grooves; the action part comprises: the rotor comprises a rotor iron core, an iron core coil, a rotor outer shell, an end cover and a rotor inner shell; the 6 rotor iron cores are arranged in a shell formed by a rotor outer shell, an end cover and a rotor inner shell; the iron core coil is wound in a wire slot of the rotor iron core, an air gap exists between the rotor inner shell and the stator part, and the hexagonal prism-shaped stator and the rotor part are coaxially assembled. The linear motor has high power density, generates electromagnetic thrust in a magnetic field space in the circumferential direction by utilizing the linear motor, has six independently controlled motor units, can continuously and stably operate by changing a control strategy after any motor unit fails, has excellent fault-tolerant capability, has better operation stability compared with the traditional single-side and double-side linear motors, and can more effectively eliminate the space asymmetric radial force.

Description

Six-unit permanent magnet linear motor

Technical Field

The invention relates to a permanent magnet linear motor, in particular to a six-unit high-power-density permanent magnet linear motor, and belongs to the technical field of motors.

Background

The pollution and development cost are higher and higher in the using process of the traditional energy, and people pay attention to the development and utilization of renewable energy. Currently, the renewable energy sources which can be utilized mainly include solar energy, wind energy, wave energy and the like.

The ocean occupies 70 percent of the total area of the earth, so the ocean energy resource development has very wide prospect. In order to improve the efficiency of wave energy power generation and the power density of a power generation device, the invention designs a six-unit permanent magnet linear motor. The most common linear motor generates output power by using the relative motion between a unilateral rotor slider and a stator with a unilateral bonded permanent magnet. In order to improve efficiency and space utilization, double-sided and cylindrical linear motors are also widely used.

Due to the influence of sea wave impact, plankton growth and the like, the probability of failure of the motor after long-time work in the wave energy power generation system is high. For example, in a single-stator linear motor structure, when a winding coil fails, the whole system cannot work normally, and although the double-side linear motor has certain fault tolerance performance, unbalanced magnetic tension is generated after the double-side linear motor fails, so that the system stability is greatly reduced. In addition, the power density of the existing linear motor is low, and the efficiency of wave energy conversion is not high, which affects the development and utilization prospect of wave energy.

Therefore, in order to improve the fault tolerance rate and the equipment reliability of the system and improve the output power density, the invention designs a six-unit permanent magnet linear generator device.

Disclosure of Invention

Aiming at the prior art, the invention aims to provide a six-unit high-power-density permanent magnet linear generator device which is simple in structure, reliable in operation, good in fault tolerance and high in power density, and can meet the technical requirements on output power and torque.

In order to solve the technical problem, the six-unit permanent magnet linear motor comprises a rotor part and a stator part, wherein the stator part comprises a hexagonal prism stator 8, six side surfaces of the hexagonal prism stator 8 are respectively provided with a groove, and permanent magnets 9 are respectively arranged in the grooves;

the action part comprises: the rotor comprises a rotor iron core 1, an iron core coil 2, a rotor outer shell 5, an end cover 6 and a rotor inner shell 7; the 6 rotor iron cores 1 are arranged in a shell formed by a rotor outer shell 5, an end cover 6 and a rotor inner shell 7; the iron core coil 2 is wound in a wire slot of the rotor iron core 1, an air gap exists between the rotor inner shell 7 and the stator part, and the hexagonal prism-shaped stator 8 and the rotor part are coaxially assembled.

As an improvement of the present invention, 6 mover cores 1 are respectively in one-to-one correspondence with 6 side surfaces of the hexagonal prism stator 8.

As another improvement of the invention, an auxiliary block is arranged between the rotor iron core 1 and the end cover, and the auxiliary block comprises a glass fiber reinforced plastic auxiliary block 3 and a silicon steel sheet auxiliary block 4.

As another improvement of the present invention, one end of each of the 6 mover cores 1 is clamped in the groove 11 of the mover outer casing 5, and the other end is attached to the mover inner casing 7, and the design range of the groove depth h of the groove 11 of the mover outer casing 5 is specifically as follows:

wherein k is a margin coefficient, the value range in the design is 1.1-1.4, and F_τIs a radial electromagnetic force of the unit motor, F_nAllowable compression strength of rotor housing material, H_eThe height of the yoke part of the rotor iron core is.

As a further improvement of the present invention, three axially uniformly distributed through holes 12 are disposed between the grooves 11 of adjacent mover housings 5, and the through holes are used for passing through the core coil wires to connect the core coil wires with the power converter.

The invention has the beneficial effects that: the six-unit permanent magnet linear motor fully considers the limitations of the structure and the performance of the traditional single-side, double-side and cylindrical linear motors, optimizes the structure of the linear motor, and has higher power density and reliability.

The hexagonal prism type linear motor structure has high power density, and the electromagnetic thrust generated by the linear motor in the magnetic field space in the circumferential direction is fully utilized. The hexagonal prism type linear motor provided by the invention cannot be associated by the structure of the existing linear motor, and the electromagnetic field calculation and analysis are carried out according to the provided structure to determine the structure size.

The motor has six independently controlled motor units, and after any motor unit breaks down, the motor can continue to run stably by changing a control strategy, so that the fault-tolerant capability is excellent.

Compared with the traditional single-side and double-side linear motors, the hexagonal prism type motor provided by the invention has better operation stability and can effectively eliminate the space asymmetric radial force.

Drawings

FIG. 1 is a front sectional view of the overall assembly structure of the present invention;

FIG. 2 is a left side sectional view of the overall assembly structure of the present invention;

FIG. 3 is a front sectional view of a mover portion of the present invention;

FIG. 4 is a left side view of a mover housing of the present invention;

FIG. 5 is a left side sectional view of a portion of a mover of the present invention;

FIG. 6 is a front sectional view of a stator portion of the present invention;

fig. 7 is a permanent magnet distribution diagram of the present invention.

Detailed Description

The following further describes the embodiments of the present invention with reference to the drawings.

Referring to fig. 1 to 7, the hexagonal prism-shaped linear motor of the present invention includes: a mover and a stator. The rotor part mainly comprises 6 rotor iron cores 1, iron core coils 2 and auxiliary blocks, wherein the rotor part comprises two types of glass fiber reinforced plastic auxiliary blocks 3 and silicon steel sheet auxiliary blocks 4, and the rotor part comprises 12 rotor

outer shells

5, 2 end covers 6, a rotor inner shell 7 and the like. The stator part mainly comprises a hexagonal prism stator 8, a permanent magnet 9, a weftless tape 10 and the like.

The stator part is hexagonal prism-shaped, and the permanent magnets 9 are attached to six side surfaces and are closely arranged. The six rotor iron cores 1 are uniformly distributed around the hexagonal prism-shaped stator 8 for a circle; the iron core coil 2 is wound in the rotor iron core wire slot; one rotor core 1 and the corresponding stator part jointly form a unit of the motor. And glass fiber reinforced plastic auxiliary blocks 3 and silicon steel sheet auxiliary blocks 4 with different sizes are sequentially attached to two sides of the rotor iron core. The rotor outer shell 5 is positioned outside the rotor iron core 1, the rotor inner shell 7 is positioned between the stator part and the rotor iron core 1, is tightly attached to the rotor iron core 1, and has an air gap with the stator part. The mover inner case 7 and the mover outer case 5 jointly act on the mover core 1 to be fixed. The end covers 6 are positioned on two sides of the rotor outer shell 5 and fixed with the rotor outer shell 5 and the rotor inner shell 7.

The size fit of the groove of the rotor outer shell 5 and the rotor iron core 1, the size fit of the glass fiber reinforced plastic auxiliary block 3 and the silicon steel sheet auxiliary block 4 and the rotor outer shell 5, and the size fit of the rotor inner shell 7 and the rotor iron core 1 are transition fit; the rotor outer shell 5 is connected with the end cover 6 through bolts, and the end cover 6 is matched with the rotor inner shell 7 in a clearance fit mode.

Three axially and uniformly distributed through holes 12 are formed between every two rotor shell grooves 11 on the rotor shell 5 and are used for penetrating through the lead of the iron core coil 2 to connect the lead with the power converter; and fillet treatment is carried out between the grooves of the two rotor shells. The hexagonal prism stator 8 and the mover part are coaxially assembled. The permanent magnet 9 and the hexagonal prism-shaped stator 8 are in adhesive connection, are closely arranged along the axis and are uniformly distributed on six surfaces of the hexagonal prism-shaped stator 8 around the axis; and a weftless tape 10 is bound outside the hexagonal prism stator 8 and used for reinforcing the permanent magnet 9.

The design of the important parameters is as follows:

in conjunction with fig. 6, the design range of the cross-sectional width D of the permanent magnet 9 is as shown in formula (1).

Wherein, P_emIs the total electromagnetic power of the linear motor, N is the number of turns of the winding coil, B₀Is a permanent magnet surface magnet_eqFor coil equivalent radial length, I_NAnd R is the length of the circumference radius of the hexagonal prism stator for the rated current value of the winding.

The design range of the groove grooving depth h of the rotor shell part is shown as formula (2).

The working process is as follows:

the working process of the generator is essentially a process of converting mechanical energy into electric energy, wherein the input quantity is thrust and speed, and the output quantity is voltage and current. The thrust acts on a rotor part of the six-unit high-power-density permanent magnet linear motor to make the rotor part perform linear reciprocating motion relative to a stator part which is coaxially assembled. When the rotor part moves, the winding coil cuts the magnetic induction lines, and induced electromotive force is generated by utilizing the electromagnetic induction principle, so that three-phase alternating current voltage is output. Six units of the designed motor can be independently assembled and can be independently controlled through respective drivers, and each unit outputs three-phase alternating current. The permanent magnet is magnetized in the radial direction and is installed in an oblique pole mode. The driving mode is the same as that of a common three-phase generator, and a control strategy of the common three-phase permanent magnet synchronous motor can also be adopted.

Claims

1. The utility model provides a six unit permanent magnet linear motor, includes active cell part and stator part, its characterized in that: the stator part comprises a hexagonal prism stator (8), six side surfaces of the hexagonal prism stator (8) are respectively provided with a groove, and permanent magnets (9) are respectively arranged in the grooves;

the action part comprises: the rotor comprises a rotor iron core (1), an iron core coil (2), a rotor outer shell (5), an end cover (6) and a rotor inner shell (7); the 6 rotor iron cores (1) are arranged in a shell formed by a rotor outer shell (5), an end cover (6) and a rotor inner shell (7); the iron core coil (2) is wound in a wire slot of the rotor iron core (1), an air gap exists between the rotor inner shell (7) and the stator part, and the hexagonal prism-shaped stator (8) and the rotor part are coaxially assembled; a glass fiber reinforced plastic auxiliary block is arranged between the rotor iron core (1) and the end cover; the length of the rotor part is less than that of the stator part;

six units of the motor are independently controlled by respective drivers, and each unit outputs three-phase alternating current;

the design range of the section width D of the permanent magnet (9) satisfies the following conditions:

wherein, P_emIs the total electromagnetic power of the linear motor, N is the number of turns of the winding coil, B₀Is a permanent magnet surface magnet_eqFor coil equivalent radial length, I_NIs the winding amountThe constant current value R is the length of the circumference radius of the hexagonal prism stator;

one end of each rotor iron core (1) is clamped in a groove (11) of the rotor shell (5), the other end of each rotor iron core is attached to the rotor inner shell (7), and the design range of the groove depth h of the groove (11) of the rotor outer shell (5) is as follows:

2. A six-unit permanent magnet linear motor according to claim 1, characterized in that: the 6 rotor iron cores (1) are respectively in one-to-one correspondence with 6 side faces of the hexagonal prism-shaped stator (8).

3. A six-unit permanent magnet linear motor according to claim 1 or 2, characterized in that: and a silicon steel sheet auxiliary block is arranged between the rotor iron core (1) and the end cover.

4. A six-unit permanent magnet linear motor according to claim 1, characterized in that: three through holes (12) which are uniformly distributed in the axial direction are arranged between the grooves (11) of the adjacent rotor shells (5), and the through holes are used for penetrating through iron core coil leads to be connected with a power supply converter.