阅读说明：本技术 一种基于Halbach阵列的双自由度振动能量采集装置 (Halbach array-based double-freedom-degree vibration energy collecting device ) 是由 袁天辰 宰道生 杨俭 宋瑞刚 于 2020-12-12 设计创作，主要内容包括：本发明涉及一种基于Halbach阵列的双自由度振动能量采集装置,包括基座(1),固定在基座(1)上的主梁(2),以及与主梁(2)的自由端垂直连接的第一副梁(3)和第二副梁(4),所述第一副梁(3)的自由端上设有感应线圈(6),所述第二副梁(2)的自由端连接空心六棱柱(7),所述空心六棱柱(7)的六棱柱面对应第一副梁(3)设置,所述空心六棱柱(7)的内表面设有永磁阵列(8)。与现有技术相比,本发明具有拓宽单自由度悬臂梁式能量采集装置的工作频带、提高能量采集效率等优点。(The invention relates to a Halbach array-based two-degree-of-freedom vibration energy collecting device which comprises a base (1), a main beam (2) fixed on the base (1), a first auxiliary beam (3) and a second auxiliary beam (4), wherein the first auxiliary beam (3) and the second auxiliary beam are vertically connected with the free end of the main beam (2), an induction coil (6) is arranged at the free end of the first auxiliary beam (3), the free end of the second auxiliary beam (2) is connected with a hollow hexagonal prism (7), the hexagonal prism surface of the hollow hexagonal prism (7) is arranged corresponding to the first auxiliary beam (3), and a permanent magnet array (8) is arranged on the inner surface of the hollow hexagonal prism (7). Compared with the prior art, the single-degree-of-freedom cantilever beam type energy collecting device has the advantages of widening the working frequency band of the single-degree-of-freedom cantilever beam type energy collecting device, improving the energy collecting efficiency and the like.)

1. The utility model provides a two degree of freedom vibration energy collection devices based on Halbach array, its characterized in that includes base (1), fixes girder (2) on base (1) to and first vice roof beam (3) and second vice roof beam (4) that thickness and quality all are inequality of being connected perpendicularly respectively with the free end of girder (2), be equipped with induction coil (6) on the free end of first vice roof beam (3), hollow hexagonal prism (7) are connected to the free end of second vice roof beam (4), the hexagonal prism face of hollow hexagonal prism (7) corresponds first vice roof beam (3) and sets up, the internal surface of hollow hexagonal prism (7) is equipped with permanent magnet array (8).

2. The Halbach array-based two-degree-of-freedom vibration energy harvesting device according to claim 1, wherein the hollow hexagonal prism (7) is of a hollow straight hexagonal prism structure, the cross section of the hollow hexagonal prism (7) is of a hollow regular hexagonal structure, and the hollow part of the hollow hexagonal prism (7) is of a regular hexagonal structure.

3. The Halbach array-based two-degree-of-freedom vibration energy harvesting device is characterized in that six permanent magnet arrays (8) are attached to the inner surface of the hollow hexagonal prism (7), each permanent magnet array is located at the center of the inner surface of the hollow hexagonal prism (7), and the permanent magnet arrays (8) are arranged at the centers of the inner surfaces of the side surfaces of the hollow hexagonal prism (7).

4. The Halbach array-based two-degree-of-freedom vibration energy harvesting device according to claim 2, wherein the top of the free end of the first secondary beam (3) is provided with an iron core (5), and the induction coil (6) is wound on the iron core (5).

5. The Halbach array-based two-degree-of-freedom vibration energy harvesting device according to claim 4, wherein the bottom surface of the iron core (5) is arranged corresponding to the center position of the hexagonal prism surface of the hollow hexagonal prism (7).

6. The Halbach array based two degree of freedom vibration energy harvesting device according to claim 3, wherein the permanent magnet array (8) is a Halbach permanent magnet array.

7. The Halbach array-based two-degree-of-freedom vibration energy harvesting device according to claim 6, wherein the permanent magnet array (8) is a linear Halbach permanent magnet array.

8. The Halbach array-based two-degree-of-freedom vibration energy collecting device according to claim 4, wherein the iron core (5) is connected with the first auxiliary beam (3) through epoxy glue between the permanent magnet array (8) and the hollow hexagonal prism (7).

9. The Halbach array based two degree of freedom vibration energy harvester according to claim 1, wherein the top surface of the first secondary beam (3) and the top surface of the second secondary beam (4) are in the same plane.

10. The Halbach array based two degree of freedom vibration energy harvester according to claim 1, wherein the free end of the second secondary beam (4) is welded to the hollow hexagonal prism (7).

Technical Field

The invention relates to the technical field of energy recovery, in particular to a double-freedom-degree vibration energy collecting device based on a Halbach array.

Background

Energy crisis is one of the most concerned problems in the world today, and scientific workers in various countries are always striving to find and develop new energy sources to solve the problems of energy shortage and traditional energy source usage, and potential available energy sources in the environment are: solar energy, vibration, noise, temperature differences, etc., where vibrational energy is nearly ubiquitous and has a high energy density. Taking a subway system as an example, the subway generates large vibration energy in the running process and radiates to the outside through wheel track noise, so that a large amount of energy loss is caused.

There are three main forms of conversion of vibration energy harvesters currently under study: piezoelectric, capacitive, and electromagnetic. The basic principle of the electromagnetic vibration energy collector is a Faraday electromagnetic induction law, namely when magnetic flux passing through the area enclosed by a closed loop changes, induced electromotive force can be generated in the loop; compared with piezoelectric and capacitive vibration energy collectors, electromagnetic vibration energy collectors have the advantages of small size, high sensing frequency, process compatibility with semiconductor technology, no need of external drive, capability of being used in various severe environments and the like. Most of the existing electromagnetic vibration energy collectors are single-degree-of-freedom models, namely single-degree-of-freedom right-angle cantilever beam type vibration energy collectors, however, the single-degree-of-freedom models can only collect energy around a single frequency, so that the electromagnetic vibration energy collectors have great limitation, cannot adapt to complex and variable vibration environments, and are low in energy output efficiency.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide a double-freedom-degree vibration energy collecting device based on a Halbach array.

The purpose of the invention can be realized by the following technical scheme:

the utility model provides a two degree of freedom vibration energy collection system based on Halbach array, includes the base, fixes the girder on the base to and first secondary roof beam and the secondary roof beam of second that the thickness and the quality all are all inequality of being connected perpendicularly respectively with the free end of girder, be equipped with induction coil on the free end of first secondary roof beam, hollow hexagonal prism is connected to the free end of second secondary roof beam, the hexagonal prism face of hollow hexagonal prism corresponds first secondary roof beam setting, the internal surface of hollow hexagonal prism is equipped with the permanent magnetism array.

Further, the hollow hexagonal prism is of a hollow straight hexagonal prism structure, the cross section of the hollow hexagonal prism is of a hollow regular hexagonal structure, and the hollow part of the hollow hexagonal prism is of a regular hexagonal structure.

Furthermore, six permanent magnet arrays are attached to the inner surface of the hollow hexagonal prism, each permanent magnet array is located at the center of the inner surface of the hollow hexagonal prism, and the permanent magnet arrays are arranged at the centers of the inner surfaces of the side surfaces of the hollow hexagonal prism.

Further, an iron core is arranged at the top of the free end of the first secondary beam, and the induction coil is wound on the iron core.

Further, the bottom surface of the iron core is arranged corresponding to the center position of the hexagonal prism surface of the hollow hexagonal prism.

Furthermore, the permanent magnet array adopts a Halbach permanent magnet array.

Furthermore, the permanent magnet array adopts a linear Halbach permanent magnet array.

Further, between permanent magnetism array and the hollow hexagonal prism, pass through epoxy and paste between iron core and the first auxiliary beam and be connected.

Further, a top surface of the first secondary beam is in the same plane as a top surface of the second secondary beam.

Further, the free end of the second secondary beam is connected with the hollow hexagonal prism in a welding mode.

If the device is excited externally, the first secondary beam and the second secondary beam of the device move along with the first secondary beam, the permanent magnet array on the hollow hexagonal prism connected with the second secondary beam and the induction coil on the first secondary beam move relatively, the magnetic flux on the induction coil changes, and induced electromotive force is generated at two ends of the induction coil according to a Faraday's law of electromagnetic induction. The permanent magnet array in the device adopts a linear Halbach array, a unilateral magnetic field is formed inside the hollow hexagonal prism, and a larger flux linkage change gradient can be generated in the induction coil, so that the energy collection efficiency is improved.

Compared with the prior art, the double-freedom-degree vibration energy collecting device based on the Halbach array at least has the following beneficial effects:

1) the invention adopts a double-freedom cantilever beam structure for energy collection, the cantilever beam structure is simple in structure, low in rigidity and easy to realize in the actual environment, and can obtain larger output power under lower vibration frequency, in addition, a single-freedom energy collector can only work at a certain fixed resonance frequency, and the double-freedom energy collector of the invention can have two resonance frequencies, so that the working bandwidth of the energy collection device can be improved, namely, the invention not only ensures the advantages of a right-angle cantilever beam vibration energy collector, but also widens the working frequency band of the single-freedom cantilever beam energy collection device, and can better adapt to the actual complex and variable vibration environment;

2) by adopting a linear Halbach array mode, a larger flux linkage change gradient can be generated in the induction coil, so that the efficiency of energy collection is improved;

3) the permanent magnet material adopted by the linear Halbach permanent magnet array is NdFeB, and the material has a higher maximum energy product, so that the smaller the volume of the permanent magnet material required under the same electric field intensity is, the material is saved, and the volume of the whole device is reduced;

4) the invention has simple structure and high reliability and has positive significance in the aspects of energy conservation and emission reduction.

Drawings

FIG. 1 is a schematic three-dimensional structure diagram of a two-degree-of-freedom vibration energy collecting device based on a Halbach array in an embodiment;

FIG. 2 is a right view structural schematic diagram of the Halbach array-based two-degree-of-freedom vibration energy collecting device in the embodiment;

the reference numbers in the figures indicate:

1. the device comprises a base, 2, a main beam, 3, a first auxiliary beam, 4, a second auxiliary beam, 5, an iron core, 6, an induction coil, 7, a hollow hexagonal prism, 8 and a permanent magnet array.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, shall fall within the scope of protection of the present invention.

Examples

The Halbach Array (Halbach Array) is a new type of permanent magnet arrangement, and the Array is an approximate ideal structure in engineering, and the field intensity in unit direction is enhanced by using special arrangement of magnet units. The array structure arranges the permanent magnets with different magnetization directions according to a certain sequence, so that the magnetic field on one side of the array is obviously enhanced, the magnetic field on the other side of the array is obviously weakened, and the magnetic field which is ideally distributed in space in advance is easily obtained.

The invention provides a double-freedom-degree vibration energy collecting device based on a Halbach array according to the principle of the Halbach array, and as shown in figure 1, the device comprises a base 1, a main beam 2, a first auxiliary beam 3, a second auxiliary beam 4, an iron core 5 and an induction coil 6.

The main beam 2 is fixed on the base 1, and the main beam 2 is a standard cantilever beam with a rectangular cross section. The bottom of the main beam 2 is connected with the base 1, and the top is connected with the two auxiliary beams 3 and 4. The first auxiliary beam 3 is a cantilever beam with a rectangular cross section, one end of the first auxiliary beam 3 is vertically connected with the top of the main beam 2, an iron core 5 is fixed above the other end of the first auxiliary beam, and an induction coil 6 is wound on the periphery of the iron core 5.

The number of the second secondary beams 4 is two, and the second secondary beams 4 are cantilever beams with rectangular cross sections. Two second secondary beams 4 are arranged on either side of the first secondary beam 3. One end of each second auxiliary beam 4 is vertically connected with the top of the main beam 2, and the other end of each second auxiliary beam is connected with a hollow hexagonal prism 7. The second secondary beam 4 and the hollow hexagonal prism 7 are connected together by adopting a welding process to form a rigid body. The top surface of the first sub-beam 3 is in the same plane as the top surface of the second sub-beam 4, but of different thickness, so that the two beams are of different stiffness. Furthermore, the first secondary beam 3 has a different mass than the two second secondary beams 4. Because the first secondary beam 3 and the second secondary beam 4 have different rigidity and different mass, the whole device structure has two natural frequencies when vibrating, and therefore the device is a two-degree-of-freedom system.

The hollow hexagonal prism 7 is a hollow straight hexagonal prism structure, the cross section of the hollow hexagonal prism 7 is a hollow regular hexagon, the hollow part is also in a regular hexagon structure, the included angle between two adjacent side surfaces of the hollow hexagonal prism 7 is 120 degrees, and two hexagonal prism surfaces of the hollow hexagonal prism 7 are arranged corresponding to the end part of the first auxiliary beam 3. The other ends of the two second secondary beams 4 are respectively fixed on two column edges which are arbitrarily and symmetrically arranged on the hollow hexagonal prism 7. Six permanent magnet arrays 8 are attached to the inner walls of the six side faces of the hollow hexagonal prism 7, and each permanent magnet array 8 is located in the center of the inner wall of each of the six side faces of the six prism sides of the hollow hexagonal prism 7. The permanent magnet array 8 is arranged by adopting a Halbach array, and the Halbach permanent magnet array can arrange permanent magnets in different magnetization directions according to a certain rule, so that a small amount of permanent magnets can generate a stronger unilateral magnetic field, the space utilization efficiency is increased, and the energy collection efficiency is improved.

In this embodiment, as a preferable scheme, the permanent magnet array 8 is a linear Halbach permanent magnet array. The linear Halbach permanent magnet array is the most basic Halbach array forming form, the array magnet can be regarded as the combination of a radial array and a tangential array, the linear Halbach permanent magnet array can generate larger flux linkage change gradient on the upper surface of the magnet, the unilateral magnetic field is effectively enhanced, and the linear Halbach permanent magnet array has obvious advantages in energy recovery. As a further implementation of this embodiment, the permanent magnet material used in the linear Halbach permanent magnet array is NdFeB, which has a higher maximum energy product (BH product); therefore, the smaller the volume of the permanent magnetic material required under the same electric field strength, which is beneficial to saving materials and reducing the volume of the device.

The induction coil 6 is wound outside the iron core 5, so that the magnetic field intensity is increased through the iron core 5, and the iron core 5 can concentrate magnetic lines around the induction coil 6 and circulate from the iron core 5. In this embodiment, as a preferred scheme, the material of the iron core 5 is silicon steel, which has a high magnetic permeability and a narrow magnetic hysteresis loop, and the magnetic material is not easily saturated, and the volume of the iron core made of silicon steel can be made smaller under the condition of the same output power. Preferably, the induction coil 6 is a multi-layer coil structure, and the coil material is copper.

In the invention, one end of the first secondary beam 3 is connected with the central position of the top of the main beam 2, and the two second secondary beams 4 are symmetrically arranged at two sides of the first secondary beam 3, so that the iron core 5 on the first secondary beam 3 corresponds to the central position of the hollow hexagonal prism 7, as shown in fig. 2.

The working principle of the double-freedom-degree vibration energy collecting device based on the Halbach array is as follows:

if the device is excited externally, the first secondary beam 3 and the second secondary beam 4 of the device move along with the first secondary beam, the permanent magnet array 8 on the hollow hexagonal prism 7 connected with the second secondary beam 4 and the induction coil 6 on the first secondary beam 3 move relatively, the magnetic flux on the induction coil 6 changes, and induced electromotive force is generated at two ends of the induction coil 6 according to Faraday's law of electromagnetic induction. The permanent magnet array 8 in the device adopts a linear Halbach array, a unilateral magnetic field is formed inside the hollow hexagonal prism 7, and a larger flux linkage change gradient can be generated in the induction coil 6, so that the energy collection efficiency is improved.

As a further technical scheme of the invention, epoxy glue is adopted between the iron core 5 and the first auxiliary beam 3 and between the permanent magnet array 8 and the inner surface of the hollow hexagonal prism 7 for adhesion; the epoxy glue has the characteristics of water resistance, chemical corrosion resistance, glittering and translucent property and the like; and the epoxy glue has high dielectric property and surface leakage resistance, can play an insulating role when being used at the bottom of the iron core 5, can effectively prevent the induction coil 6 from being contacted with the cantilever beam (the first auxiliary beam 3) to generate electric leakage, and further contributes to improving the energy collection efficiency.

As a further technical scheme of the invention, the main beam 2, the first secondary beam 3 and the second secondary beam 4 are made of spring steel. Spring steels have high tensile strength, elastic limit, and high fatigue strength. Can ensure that the main beam and the auxiliary beam can not generate fatigue damage under high-frequency vibration.

The invention adopts the cantilever beam structure with two degrees of freedom to collect energy, the cantilever beam structure is easy to realize in the actual environment due to simple structure and low rigidity, and can obtain larger output power under lower vibration frequency, in addition, the energy collector with one degree of freedom can only work at a certain fixed resonance frequency, but the energy collector with two degrees of freedom of the invention can have two resonance frequencies, thus the working bandwidth of the energy collecting device can be improved, namely the invention not only ensures the advantages of the right-angle cantilever beam vibration energy collector, but also widens the working frequency band of the energy collecting device with one degree of freedom of the cantilever beam, and can better adapt to the actual complex and variable vibration environment.

While the invention has been described with reference to specific embodiments, the invention is not limited thereto, and those skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope of the invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.