KR102420482B1 - Electromagnetic energy harvester - Google Patents

Abstract

A shaft reciprocating by an external force; A hollow inner frame attached to the shaft, in which a cylindrical Halbach arrangement portion is formed in which an axial magnet and a radial magnet are repeatedly alternately arranged; and a hollow outframe accommodated outside the inner frame and having a coil portion formed corresponding to the position where the Halbach arrangement portion is formed, wherein the coil portion generates magnetic flux linkage by relative motion between the shaft and the inner frame. An electromagnetic energy harvester further comprising a spacer in which a slot in which a generating coil is wound is formed to be spaced apart from each other by a predetermined interval, and the Halbach arrangement part is disposed on a surface facing the coil part of the radial magnet is disclosed. Therefore, it maximizes the value of the flux linkage and minimizes the leaked flux, thereby providing more improved power generation with the same vibration energy.

Description

Electromagnetic Energy Harvester {ELECTROMAGNETIC ENERGY HARVESTER}

The present invention relates to an electromagnetic energy harvester that converts vibrational energy into electrical energy using relative motion between a magnet and a coil.

The electromagnetic energy harvester includes a structure that generates electrical energy according to a relative motion between a magnet and a coil by external vibration energy. At this time. In relation to the arrangement of magnets, a conventional halbach arrangement structure is used.

1 is a view showing an electromagnetic energy harvester having a conventional Halbach arrangement structure. Referring to FIG. 1 , the Halbach arrangement structure has a form in which a plurality of magnets are repeatedly alternately arranged with different magnetization directions based on a coil portion wound thereon. The coil part means a spiral coil, the axial direction means an extension direction of the coil part, and the radial direction means a direction in which the radius of the coil part perpendicular to the axial direction extends.

Specifically, it has a Halbach arrangement structure in which an axial magnet and a radial magnet that change the direction of magnetic flux formed according to the magnetization direction alternately repeatedly.

Magnets can be arranged in such a regular arrangement direction, thereby generating a sinusoidal magnetic flux distribution in the air. At this time, the coil unit generates electric energy by linking the magnetic flux generated from the magnet while relative motion in the axial direction. Relative motion refers to, but is not limited to, reciprocating linear motion.

That is, the magnetic flux linkage generated according to the relative motion between the coil unit and the Halbach arrangement is connected to an external circuit to produce electrical energy. However, the conventional Halbach arrangement structure has a problem in that the magnitude of the magnetic flux linkage is limited within a certain range, so that the generated electrical energy cannot be increased any more.

Republic of Korea Patent Registration No. 10-1297114 (Registered on Aug. 9, 2013) Republic of Korea Patent Registration No. 10-1275286 (Registered on June 10, 2013) Republic of Korea Patent Publication No. 10-2010-0036526 (published on 04.08. 2010)

The embodiment of the present invention has been devised to solve the above problems, and by improving the Halbach arrangement structure of the magnet part adopted in the conventional electromagnetic energy harvester, the value of the magnetic flux linkage from the Halbach arrangement part to the coil part is maximized, and , to minimize the leakage flux. Accordingly, an object of the present invention is to provide an energy conversion device that generates more electrical energy from the same vibration energy.

In an embodiment of the present invention, in order to solve the above problems, the Halbach arrangement part in which the axial magnet and the radial magnet are repeatedly alternately arranged and the slot in which the coil is wound are spaced apart from each other by a predetermined distance, and the Halbach Electromagnetic energy comprising a coil unit for generating magnetic flux linkage by reciprocating relative to the arrangement unit in an axial direction, and wherein the Halbach arrangement unit further includes a spacer disposed on a surface facing the coil unit of the radial magnet Harvester is provided.

The pole spacing between the axial magnet and the radial magnet and the axial length between the slot and the slot may be formed in a 1:1 structure.

In addition, the coil unit may have a one-phase structure in which coils having different winding directions are alternately arranged or a two-phase structure in which coils having the same winding direction are arranged. However, in the case of having a two-phase structure, an even number of slots and magnets are formed.

It may further include a cover for covering the outer surface of the axial magnet and the spacer, the cover is preferably formed of a magnetic material.

A metal layer may be further formed on the outer surface of the Halbach arrangement.

The thickness of the radial magnet preferably has a length corresponding to about 50% to 88% of the thickness of the axial magnet, and the width of the spacer has a length corresponding to about 60% to 65% of the pole spacing. it is preferable

The electromagnetic energy harvester having the above configuration may have a cylindrical shape.

According to the problem solving means of the present invention as described above, various effects including the following items can be expected. However, the present invention is not established only when exhibiting all of the following effects.

The electromagnetic energy harvester structure according to an embodiment of the present invention replaces a part of the radial magnet of the conventional Halbach arrangement structure with a spacer and arranges it on the side facing the coil unit, and links from the Halbach arrangement unit to the coil unit. can maximize the magnetic flux value and at the same time reduce the amount of permanent magnets used.

In addition, it further includes a metal layer on the outer surface of the cover and the Halbach arrangement formed of a magnetic material covering the outer surface of the axial magnet and the spacer, so that the tooth or back iron of the outframe or the back iron or the shaft ( The magnetic flux leaked to the shaft) can be minimized. As a result, by increasing the magnitude of the magnetic flux linkage inside the coil unit, the amount of electrical energy converted according to the embodiment may be approximately doubled.

1 is a view showing an electromagnetic energy harvester having a conventional Halbach arrangement structure.
2 is a view showing an electromagnetic energy harvester according to a first embodiment of the present invention.
3 is a view showing a first embodiment in which a coil unit has a one-phase structure;
4A is a view showing a first embodiment having a two-phase structure in a direction in which a coil unit emerges.
4B is a view showing a first embodiment having a two-phase structure in a direction in which a coil unit enters.
5 is a view showing that the pole spacing and the axial length between the slot and the slot are formed in a 1:1 structure.
6 is a view showing the ratio of the thickness of the axial magnet to the thickness of the radial magnet and the maximum amount of power generated accordingly.
7 is a view showing the ratio of the pole spacing to the width of the radial magnet and the maximum amount of power generated accordingly.
8 is a view showing an electromagnetic energy harvester according to a second embodiment of the present invention.
9 is a cross-sectional view taken along lines IX-IX of FIG. 8;
FIG. 10 is an enlarged view of the Halbach arrangement part and the coil part of FIG. 9 .
11 is a view showing a second embodiment in which a coil unit has a one-phase structure;
12 is a view showing a second embodiment in which a coil unit has a two-phase structure;
13 is a view showing an electromagnetic energy harvester having only an axial magnet and a spacer.
FIG. 14 is a view showing a comparison of the amount of power generation between the electromagnetic energy harvester of the present invention and the electromagnetic energy harvester of FIGS. 1 and 13 .

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

[First embodiment]

2 is a diagram illustrating an electromagnetic energy harvester according to a first embodiment of the present invention. FIG. 3 is a view showing a first embodiment having a one-phase structure of the coil unit, FIG. 4A is a view showing a first embodiment having a two-phase structure in a direction in which the coil unit comes out, and FIG. 4B is a view showing a direction in which the coil unit enters. It is a view showing a first embodiment having a two-phase structure of.

Referring to FIG. 2 , in the electromagnetic energy harvester according to the first embodiment, the Halbach arrangement 100 and the coil 211 in which the axial magnet 111 and the radial magnet 112 are repeatedly alternately arranged are Slots 210 to be wound are formed to be spaced apart by a predetermined interval, and include a coil unit 200 that reciprocates relative to the Halbach arrangement unit 100 in an axial direction to link magnetic flux.

In the Halbach arrangement 100, an axial magnet 111 in which magnetic flux is generated in the axial direction according to the magnetization direction and a radial magnet 112 in which magnetic flux is generated in a direction perpendicular to the axial direction are repeatedly alternately arranged. , a spacer 120 replacing a portion of the radial magnet 112 is further disposed on the surface facing the coil unit 200 of the radial magnet 112 to have an improved Halbach arrangement structure.

Here, as shown in FIG. 2 , one axial magnet 111 and one radial magnet 112 are defined as constituting one pole (A, 110). Therefore, the Halbach arrangement 100 is composed of a plurality of poles 110 and a plurality of spacers 120 .

The width of the spacer 120 is the same as that of the radial magnet 112 , and the sum of the thicknesses of the radial magnet 112 and the spacer 120 in a state where a part of the radial magnet 112 is replaced is the axial magnet It is the same as the thickness of (111), so it does not protrude to the outside of the Halbach arrangement 100, and is formed as a single member.

The spacer 120 is disposed between the axial magnets 111 and on the side of the radial magnets 112 to have a structure in which three sides are surrounded by the magnets. The peripheral magnetic flux of the spacer 120 is formed by repeating the incoming and outgoing directions from one pole 110 composed of one axial magnet 111 and one radial magnet 112 .

By harvesting the energy generated by the relative motion of the magnetic flux generated by the pole 110 and the coil 211, the axial magnet 111 and the radial magnet 112 are stable without receiving energy from the outside. It is preferably formed of a permanent magnet in which a magnetic field is generated and maintained, and the spacer 120 is preferably formed of a magnetic material for concentration of magnetic flux dispersed around it.

In addition, it may further include a cover 300 covering the outer surface of the axial magnet 111 and the spacer 120 of the Halbach arrangement 100 . This is to protect the permanent magnet from the external environment and prevents foreign substances from entering.

Whether the material constituting the cover 300 is magnetic is not a problem, but when the cover 300 is formed of a magnetic material, it reduces the leaking magnetic flux, and has the effect of improving the amount of power generation by about 30% compared to the case where the cover 300 is formed of a non-magnetic material. , is preferably formed of a magnetic material. The results are presented in the table below.

Power generation (W) When formed with a magnetic material (S20C) In case of non-magnetic material (stainless steel)
maximum power 505.43
(127.9%) 395.17
(100%)
average power generation 195.97
(128.9%) 152.08
(100%)

The coil unit 200 is formed of a single member, and the slot 210, which is a space in which the coil 211 is wound, is biased toward the Halbach arrangement unit 100, and is spaced apart from each other by a predetermined interval. Between the slot and the slot is defined as a tooth (tooth, 220), the other part is defined as a back iron (back iron, 230).

The coil unit 200 makes a relative motion with the Halbach arrangement unit 100 in which the direction of magnetic flux is repeatedly changed to link the magnetic flux to the coil 211, transfer it to a connected external circuit, and convert it into electrical energy to generate electricity. At this time, the spacer 120 maximizes the magnetic flux value by preventing the dispersion of the generated flux linkage.

The number of poles 110 and the number of slots 210 composed of one axial magnet and one radial magnet are arranged in a 1:1 ratio, but in order to concentrate the flux linkage distributed to both ends of the coil unit 200 For this purpose, it is preferable that one pole 110 and one spacer 120 are further disposed at both ends of the Halbach arrangement 100 as in the portion indicated by 'E' in FIG. 2 .

The Halbach arrangement unit 100 and the coil unit 200 are in relative motion in which at least one of the two positions is changed, and it is preferable to perform a reciprocating linear motion or a rotational motion depending on the structure. In order to prevent energy loss caused by friction during relative motion, it is preferable that a predetermined air gap 240 is formed between the Halbach arrangement 100 and the coil unit 200 .

The coil 211 wound on the slot 210 has a one-phase or two-phase structure. As shown in FIG. 3 , the one-phase structure corresponds to a series connection with a structure in which the coil 211 wound on the slot 210 is alternately disposed in the entering direction and the outgoing direction, and the number of slots is arbitrarily adjusted. It is possible. As shown in FIGS. 4A and 4B , the two-phase structure corresponds to a parallel connection in a structure in which the direction of the coil 211 wound on the slot 210 is uniformly arranged in the direction in which all of them enter or the direction in which they exit the slot. An even number of numbers must be placed. This is to transfer the generated magnetic flux linkage to an external circuit (not shown) by connecting both ends of the coil to different poles, respectively.

In order to improve the amount of power generation, the resistance of the coil 211 is preferably equal to the load resistance of the external circuit. Accordingly, in the case of a one-phase structure, it is preferable that the resistance of the entire coil corresponds to a series connection and is equal to the load resistance, and in the case of a two-phase structure, it corresponds to a parallel connection and the resistance of each coil is preferably equal to the load resistance. In addition, the load resistance of the external circuit is preferably connected in series.

5 is a view showing that the pole spacing and the axial length between the slot and the slot have a mutually 1:1 structure, and FIG. 6 is the ratio of the thickness of the axial magnet to the thickness of the radial magnet and the maximum amount of power generated accordingly. 7 is a view showing the ratio of the pole spacing to the width of the radial magnet and the maximum amount of power generated accordingly.

The present invention is an energy harvester that maximizes the amount of power generation by having an improved structure further including a spacer 120 in the conventional energy harvester having a Halbach arrangement structure. Therefore, the most effective spacer 120 is proposed by measuring the maximum output power (W) using the size of the spacer 120 as a variable.

5, the Halbach arrangement 100 of the present invention adopts a structure in which the pole 110 spacing (c) and the axial length (d) of the slot 210 are 1:1. Accordingly, it is possible to maximize the value of the magnetic flux linkage in the coil 211, it is possible to reduce the use of permanent magnets and reduce the size to improve the output density of the generator. (It can be improved by about 30% to 40% compared to the previous one.)

Referring to FIG. 6 , the maximum amount of power generation according to the ratio of the thickness t of the axial magnet to the thickness t1 of the radial magnet, that is, the radial magnet 112 is replaced by the spacer 120 is measured. , when the thickness of the radial magnet t1 is about 50% to 88% of the thickness t of the axial magnet, the maximum power generation W is the maximum. In this case, the maximum amount of power generation is about twice that of the energy harvester having the conventional Halbach arrangement structure.

Referring to FIG. 7 , when the pole spacing s is constant, the ratio of the width s1 of the radial magnet among the pole spacing s, that is, the maximum amount of power generation according to the width of the spacer 120 is measured. When the ratio of the width (s1) of the radial magnet (or spacer) among the pole spacing (s) composed of the axial magnet and one radial magnet of do.

Therefore, the spacer 120 has a thickness of about 12% to 50% of the thickness of the axial magnet (t), and when the width is about 60% to 65% of the pole spacing (s), maximum electricity with the same vibration energy energy can be generated.

In addition, in order to generate the maximum amount of power generation, as shown in FIG. 2 , the initial positions of the Halbach arrangement part 100 and the coil part 200 are the sides of each tooth 220 formed between the slots 210 . It is preferable that the axial magnets 111 are respectively located on the.

[Second embodiment]

8 is a view showing an electromagnetic energy harvester according to a second embodiment of the present invention, FIG. 9 is a cross-sectional view taken along lines IX-IX of FIG. 8, and FIG. 10 is the Halbach arrangement part and the coil part of FIG. It is an enlarged view. 11 is a view showing a second embodiment in which the coil unit has a one-phase structure, and FIG. 12 is a view showing a second embodiment in which the coil unit has a two-phase structure.

8 to 10 , the electromagnetic energy harvester according to the second embodiment of the present invention has a hollow shaft 400 that reciprocates by external force, is attached to the shaft 400, and has an axial magnet in a portion thereof. The hollow inner frame 1000 in which the cylindrical Halbach arrangement part 100 in which the 111 and the radial magnets 112 are repeatedly alternately arranged is formed and disposed outside the inner frame 1000, It includes a hollow outframe 2000 in which the coil unit 200 is formed corresponding to the position where the Bach arrangement unit 100 is formed. In the coil unit 200, slots 210 in which the coil 211 is wound are formed to be spaced apart from each other by a predetermined interval, and the Halbach arrangement unit 100 is a spacer ( 120) is further included.

The electromagnetic energy harvester according to the second embodiment has the same purpose and some configurations as the electromagnetic energy harvester according to the first embodiment, and descriptions of the same points will be omitted below.

The outframe 2000 of the electromagnetic energy harvester according to the second embodiment of the present invention accommodates the inner frame 1000 having the same central axis, and a fixing unit 600 is coupled to one side thereof. The fixing part 600 is formed on an extension line of the central axis, and a rod 610 extending along the central axis is connected to the inside. The inner frame 1000 has a hollow shaft 400 that reciprocates in a straight line along the central axis is attached to the inner frame, and the shaft 400 has a receiving part 410 for accommodating vibration energy at one end, and the other end. A hole 420 is formed therein to accommodate the rod 610 inside.

Therefore, when external vibration energy is received in the receiving part 410, the shaft 400 and the inner frame 1000 linearly reciprocate along the rod 610 extending into the shaft 400, and thus the Halbach arrangement part Magnetic flux linkage is generated by the relative motion of 100 and the coil unit 200 .

When this is applied to a shock absorber of a vehicle, the fixing part 600 is fixed to the vehicle body, and the receiving part 410 is connected to the wheel and receives vibration according to the road surface to accommodate the shaft 400 and the inner frame ( 1000) to generate a reciprocating motion. Accordingly, magnetic flux linkage is generated by the relative motion of the Halbach arrangement unit 100 and the coil unit 200 .

Referring to FIG. 9 , the outframe 2000 is formed in a hollow shape having a certain thickness, and a slot 210 is concavely formed on an inner surface thereof, and the coil 211 is wound along it.

The Halbach arrangement 100 is formed in a cylindrical shape, the radial magnet 112 and the axial magnet 111 have an annular structure surrounding the inner surface of the Halbach arrangement 100, and the spacer 120 has a radius It has an annular structure surrounding the outer surface of the direction magnet 112 . In this case, the axial magnets 111 are formed to be spaced apart from each other by a predetermined distance, so that the radial magnets 112 and the spacers 120 are separated into a plurality of units in the longitudinal direction by the axial magnets 111 .

In addition, the cover 300 surrounding the outer surface of the axial magnet 111 and the spacer 120 and the metal layer 500 surrounding the inner surface of the radial magnet 112 and the axial magnet 111 are further formed. desirable.

The metal layer 500 reduces magnetic flux leaking toward the shaft 400 and has the effect of increasing the amount of power generation by about 20%. The results are presented in the table below.

Power generation (W) When formed with a magnetic material (S20C) In case of non-magnetic material (stainless steel)
maximum power 395.17
(100%) 325.57
(82.4%)
average power generation 152.08
(100%) 120.29
(79.1%)

1 is a diagram illustrating an electromagnetic energy harvester having a conventional Halbach arrangement structure, FIG. 13 is a diagram illustrating an electromagnetic energy harvester having only an axial magnet and a spacer, and FIG. 14 is an electromagnetic energy harvester of the present invention. It is a view showing a comparison of the amount of power generation of the electromagnetic energy harvester of FIGS. 1 and 13 .

The electromagnetic energy harvester of the present invention is an energy harvester that maximizes the amount of electricity generated by applying the Halbach arrangement improved in the conventional Halbach arrangement structure. Therefore, we would like to present its effect.

1 is an electromagnetic energy harvester having a conventional Halbach arrangement structure, and the spacer 120 is not included. 13 is an electromagnetic energy harvester having only the axial magnet 111 and the spacer 120 and does not include the radial magnet 112 . The results are shown in the table below.

Electromagnetic energy harvester having a Halbach arrangement including spacers (invention) Electromagnetic energy harvester with conventional Halbach arrangement structure (axial magnet and radial magnet) Electromagnetic energy harvester with only axial magnet and spacer Vibration speed (m/s) 0.25 Pole spacing (mm) 11.25 Frequency (Hz) 10 Length (mm) 225 Diameter (mm) 100 Pole spacing (mm) 22.5 Air gap (mm) 1.6 number of slots and poles 8 pcs - 8 pcs
Maximum power (W) 395.17
(100%) 218.45
(55.3%) 64.43
(16.3%)
Average power generation (W) 152.08
(100%) 96.03
(63.1%) 23.15
(15.2%)

As such, the improved Halbach arrangement structure further including the spacer 120 greatly improves the amount of power generation. This is because the axial magnet 111 and the radial magnet 112 are alternately arranged to concentrate the dispersion of the flux linkage generated through the spacer 120 to maximize the density value of the magnetic flux. Therefore, it is preferable to apply it to the conventional Halbach arrangement having an axial magnet and a radial magnet.

The present invention is an electromagnetic energy harvester improved by the conventional Halbach arrangement formed only of directional magnets and radial magnets, and is an electrical energy conversion device using vibration. For example, if an electromagnetic energy harvester is installed in a shop up shock absorber, which is a vehicle suspension device, vibration energy generated by the road surface, etc. generated by the operation of the vehicle can be converted into electrical energy. That is, it is possible to effectively generate electric energy by installing it in a place where vibration is generated regardless of any cause.

In the above, preferred embodiments of the present invention have been exemplarily described, but the scope of the present invention is not limited to such specific embodiments, and may be appropriately changed within the scope described in the claims.

Inner frame : 1000 Out frame : 2000
Halbach arrangement: 100 poles: 110, A
Axial magnet : 111 Radial magnet : 112
Spacer: 120 Coil part: 200
Slot: 210 Coil: 211
Tooth: 220 Back iron: 230
Air gap: 240 Cover: 300
Shaft: 400 Receptacle: 410
Hall: 420 Metal Layer: 500
Fixed part : 600 Rod : 610
Pole spacing: c Axial length between slot and slot: d

Claims (17)

a Halbach arrangement in which poles in which the axial magnet and the radial magnet are alternately formed are repeatedly formed;
a coil unit in which slots in which a coil is wound are formed to be spaced apart from each other by a predetermined interval, and relative to the Halbach arrangement unit to generate magnetic flux linkage; and
Including; a cover formed of a magnetic material covering the outer surface of the Halbach arrangement part,
The Halbach arrangement
a spacer formed between the cover and the radial magnet and disposed on a surface facing the coil part of the radial magnet; between the slots having different axial lengths (pole spacing) of the poles It is formed in a 1:1 structure with an axial length, and the pole and the spacer are further arranged at both ends, one each,
The thickness of the radial magnet is
It has a length corresponding to 50% to 88% of the thickness of the axial magnet,
The width of the spacer is
Electromagnetic energy harvester, characterized in that it has a length corresponding to 60% to 65% of the pole spacing.
delete According to claim 1,
The coil part
An electromagnetic energy harvester having a one-phase structure in which the winding direction of the coil is alternately disposed in a direction in which it enters and exits.
According to claim 1,
The coil part
The electromagnetic energy harvester has a two-phase structure in which the winding direction of the coil is arranged in one direction, and an even number of slots are formed.
delete delete delete delete Hollow shaft reciprocating by external force;
a hollow inner frame attached to the outside of the shaft and formed with a cylindrical Halbach arrangement in which poles formed by alternating arrangement of axial magnets and radial magnets are repeatedly formed;
a hollow out frame disposed outside the inner frame and formed with a coil unit corresponding to a position at which the Halbach arrangement unit is formed;
a cover formed of a magnetic material covering the outer surface of the Halbach arrangement; and
Including; a metal layer formed on the inner side of the inner frame;
The coil part
Slots in which a coil for linking magnetic flux is wound by relative motion between the shaft and the inner frame are formed at regular intervals,
The Halbach arrangement
a spacer formed between the cover and the radial magnet and disposed on a surface facing the coil part of the radial magnet; between the slots having different axial lengths (pole spacing) of the poles It is formed in a 1:1 structure with an axial length, and the pole and the spacer are further arranged one at each end at both ends,
The thickness of the radial magnet is
It has a length corresponding to 50% to 88% of the thickness of the axial magnet,
The width of the spacer is
Electromagnetic energy harvester, characterized in that it has a length corresponding to 60% to 65% of the pole spacing.
delete 10. The method of claim 9,
The coil part
The winding direction of the coil is arranged in two phases in one direction,
An electromagnetic energy harvester in which a plurality of slots are formed.
10. The method of claim 9,
The coil part
The winding direction of the coil is alternately arranged in one phase in the entering and exiting direction,
An electromagnetic energy harvester having an even number of slots.
delete delete delete delete delete

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