An elastic resonance type rotational energy harvesting device and method

Abstract

The present invention discloses an elastic resonance type rotational energy harvesting device and method, belonging to the technical field of energy harvesting and self-powered systems. The device includes a housing, with a wind blade arranged above the housing. The wind blade is connected to a bearing inside the housing through a rotating shaft. A permanent magnet is installed on the inner ring of the bearing, and a push rod is arranged on the part of the rotating shaft located inside the bearing. The bottom end inside the housing is connected to a magnetic core through an elastic connecting piece. The magnetic core is wound with a coil and connected to a battery management module. The method includes internal rotation and external rotation, and can be applied to collect rotational or oscillating energy such as gentle breeze. In the former case, the wind energy blows the wind blade, driving the permanent magnet to rotate and generate relative motion with the magnetic core, generating an induced electromotive force, which is then rectified and charged. In the latter case, an external excitation causes the wind blade to rotate and drive the permanent magnet, interacting with the magnetic core to generate an induced electromotive force. The present invention can harvest tiny and low-frequency energy, supply energy for micro-devices, has a small device size, high power generation efficiency, flexible material selection and a wide range of applicable scenarios, and is of great significance in the field of energy harvesting.

Description

Technical Field

[0001] The present invention relates to the technical field of energy harvesting and self-powered systems, and more particularly to an elastic resonance rotary energy harvesting device and method. Background Art

[0002] The harvesting of minute energies such as blue energy and breeze energy has always been a key focus of scientific research. These energies are very common in nature. If there is a device that can harvest these energies, the application scope of such a device will be very broad. How to harvest these energies to power devices such as sensors that are not easy to replace batteries or are not suitable for continuous wired energy transmission has become a major problem. Therefore, in some remote areas or areas where it is not easy to replace batteries, etc., harvesting energy from the surrounding environment to enable it to have a self-powered system and provide a sustainable off-grid power supply for smart infrastructure or low-power sensors and communication systems is extremely important. Conventional electromagnetic power generation devices, such as hydraulic generators, large wind turbines, etc., convert mechanical energy, potential energy, etc. in nature into electrical energy. However, most of these devices are large in size and are applied in fields where a large amount of energy is harvested, and are not suitable for use in low-frequency or micro-device environments. Moreover, according to Faraday's law, once the volume of the electromagnetic power generation device is reduced, the generated electromotive force will be greatly reduced. Summary of the Invention

[0003] The object of the present invention is to provide an elastic resonance rotary energy harvesting device and method, which solves the problem that most existing devices are large in size, are applied in fields where a large amount of energy is harvested, and are not suitable for use in low-frequency or micro-device environments.

[0004] To achieve the above object, the present invention provides an elastic resonance rotary energy harvesting device, including a housing. A wind blade is provided above the housing. The wind blade is connected to a bearing disposed inside the housing through a rotating shaft. A permanent magnet is installed between the outer ring and the inner ring of the bearing. And a plurality of push rods are provided on the part of the rotating shaft located inside the bearing. A plurality of elastic connectors (spring sheets) are provided at the bottom end inside the housing. Each elastic connector is connected to a magnetic core. A coil is wound around the outer surface of each magnetic core. The coil is connected to a battery management module. Preferably, a plurality of the magnetic cores are connected to the bottom end inside the housing through a plurality of the elastic connectors and are arranged in a circular pattern.

[0005] Preferably, a gap of 2-3 mm is maintained between the magnetic core and the permanent magnet.

[0006] Preferably, the battery management module includes a battery and a rectifier. The battery is electrically connected to the coil through a circuit, and a rectifier is installed on the circuit.

[0007] Preferably, the length of the push rod is not greater than the radius of the bearing.

[0008] Preferably, the permanent magnet is made of a super-strong magnet material.

[0009] Preferably, the magnetic core is made of a high-permeability material.

[0010] An elastic resonance type rotational energy harvesting method includes: two ways of breeze energy harvesting and external rotational power generation; wherein, the elastic resonance type rotational energy harvesting device includes a wind blade, a housing, a first magnetic core, a permanent magnet, a rotor, a first coil, a rotating shaft, a first elastic connecting piece, a second coil, a second magnetic core and a second elastic connecting piece;

[0011] The breeze energy harvesting includes a first elastic connecting piece, a first magnetic core and a first coil axially arranged on the bottom of the housing;

[0012] The specific steps of the breeze energy harvesting are as follows:

[0013] S11. When the wind energy blows the wind blade to rotate, driving the rotating shaft to rotate, so that the push rod pushes the permanent magnet to rotate;

[0014] S12. During the rotation of the permanent magnet, relative movement occurs with the axially arranged first magnetic core, resulting in a change in the magnetic flux entering the first coil, so that a current and an induced electromotive force are generated in the closed first coil;

[0015] S13. The magnetic force of the permanent magnet drives the first magnetic core to move. Under the action of the elastic force of the first elastic connecting piece and the Ampere force, the first magnetic core swings back and forth, increasing the magnetic flux change rate and improving the power generation efficiency;

[0016] S14. The induced electromotive force is converted into direct current through a rectifier to charge the battery, completing the energy harvesting;

[0017] The external rotational power generation includes a plurality of second elastic connecting pieces radially arranged on the side wall of the housing. Each second elastic connecting piece is connected with a second magnetic core, and a second coil is wound around the outer surface of each second magnetic core;

[0018] The specific steps of the external rotational power generation are as follows:

[0019] S21. An external excitation causes the wind blade to rotate, driving the permanent magnet to rotate through the rotating shaft and the rotor;

[0020] S22. The permanent magnet makes relative movement with the radially arranged second magnetic core, changing the magnetic flux entering the second coil. A current and an induced electromotive force are generated in the closed second coil, and the second elastic connecting piece increases the magnetic flux change rate to achieve energy harvesting.

[0021] Therefore, the elastic resonance type rotational energy harvesting device and method with the above structure of the present invention have the following beneficial effects:

[0022] (1) The present invention can collect tiny and low-frequency energy and can be applied to the power supply scenarios of micro-devices, solving the problems that most existing devices are large in size, only applicable to the fields of collecting larger energy, and not applicable to low-frequency or micro-device environments. It can provide sustainable off-grid power for intelligent infrastructure, low-power sensors, and communication systems in remote areas or areas where it is not easy to replace batteries.

[0023] (2) By adding elastic devices such as spring pieces, according to Lenz's law, part of the external rotational mechanical energy is directly converted into induced electromotive force, and the other part is converted into elastic potential energy, which is then converted into induced electromotive force through resonant swinging. The permanent magnet drives the magnetic core to swing together, causing the originally fixed magnetic core to also have a change in magnetic flux. Under the action of the spring piece, the elastic potential energy is released, and the rate of change of magnetic flux increases, greatly improving the generation of induced electromotive force. When the magnetic core and the magnet resonate and swing, they can be staggered at the end face at the maximum relative speed, achieving the maximum electromagnetic power generation efficiency.

[0024] (3) The shapes of the permanent magnet and the soft magnetic core of the present invention can be changed according to the application scenario, and the positions of the wound magnetic core and the permanent magnet can be swapped as needed. The permanent magnet can be selected from super-strong magnets such as neodymium iron boron materials; the soft magnetic core can use a variety of high magnetic permeability materials such as silicon steel and ferrite; the spring piece can be made of materials with a certain elastic modulus and not easily interfering with the magnetic field, such as spring steel and stainless steel; the rigid housing can be selected from materials with low interference to magnetic wires, such as aluminum alloy and plastic.

[0025] The technical solution of the present invention will be further described in detail below through the accompanying drawings and embodiments. Description of the Drawings

[0026] Figure 1 It is a schematic structural diagram of an elastic resonance type rotational energy harvesting device and method of the present invention;

[0027] Figure 2 It is a schematic diagram of the bearing magnet arrangement of an elastic resonance type rotational energy harvesting device and method of the present invention;

[0028] Figure 3 It is a schematic diagram of the magnetic core swinging process of an elastic resonance type rotational energy harvesting device and method of the present invention;

[0029] Figure 4 It is a schematic diagram of an elastic resonance type internal rotational generator of an elastic resonance type rotational energy harvesting device and method of the present invention;

[0030] Figure 5 It is a schematic diagram of the voltage output example of a single pair of magnetic cores and magnets of an elastic resonance type rotational energy harvesting device and method of the present invention;

[0031] Reference Signs

[0032] 1. Wind blade, 2. Rotating shaft, 3. First magnetic core, 4. First coil, 5. First elastic connector, 6. Housing, 7. Permanent magnet, 8. Bearing, 9. Rectifier, 10. Battery, 11. Push rod, 12. Relative movement, 13. Oscillation, 14. Rotor, 15. Second magnetic core, 16. Second coil, 17. Second elastic connector. Detailed implementation mode

[0033] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] Unless otherwise defined, the technical terms or scientific terms used in the present invention should have the ordinary meanings understood by those with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar terms used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to represent relative position relationships. When the absolute position of the object being described changes, the relative position relationship may also change accordingly.

[0035] Embodiment

[0036] Since the traditional wind energy power generation device is large in size, it is not only inconvenient to install but also expensive to manufacture, and the power per unit area is also small. If an electromagnetic power generation device is to be applied in low-frequency and micro fields, the induced electromotive force generated is insufficient. Therefore, the present invention provides an elastic resonance type rotational energy harvesting device (such as Figures 1-3As shown in the figure, the elastic resonance type micro-wind energy collector consists of a wind blade 1, a housing 6, a first magnetic core 3, a permanent magnet 7, a bearing 8, a first coil 4, a rotating shaft 2, and a first elastic connecting member 5 to form a basic device structure. First, install the wind blade 1 above the rotating shaft 2 as a medium for collecting wind energy. Second, place the cylindrical permanent magnet 7 in the inner ring of the bearing 8. A push rod is connected below the rotating shaft, and the cylindrical permanent magnet 7 in the bearing 8 is pushed to rotate through the push rod 11. Under such conditions, the permanent magnet 7 can act as both a magnetic field source and a rolling element of the bearing 8. Wind energy makes the rotating shaft 8 rotate through the wind blade 1, causing the push rod 11 to push the permanent magnet 7, making the rotation more convenient. Third, the wound first magnetic core 3 is axially arranged at the bottom of the housing 6 through the first elastic connecting member 5 (spring sheet) and is arranged in a ring shape at the bottom of the housing 6. The gap between the first magnetic core 3 and the permanent magnet 7 should be as small as possible (2 - 3 mm), as long as it is ensured that no collision occurs during the swing 14. In this state, only a small relative movement 13 is required to generate a large induced electromotive force. When the wind blade 1 rotates, a relative movement 13 occurs between the permanent magnet 7 and the axially arranged first magnetic core 3, causing the magnetic flux entering the first coil 4 to change, and a current is generated in the closed first coil 4, thus generating an induced electromotive force. Whether it rotates forward, backward, or rotates back and forth, this device can collect part of the energy and convert it into electrical energy. In addition, when the permanent magnet 7 rotates, due to the extremely strong magnetic force, it will drive the first magnetic core 3 to move along. The change of the magnetic moment causes the magnetic force to continuously increase and decrease. Under the action of the elastic force and Ampere force of the first elastic connecting member 5, the elastic potential energy is continuously stored and released, realizing the continuous back-and-forth swing 14 of the first magnetic core 3, further changing the magnetic flux change rate. Among them, as shown in Error! Reference source not found., the cylindrical permanent magnets 7 can be arranged in the same direction. In this case, due to the repulsion between like poles, most of the magnetic field lines will be perpendicular downward, causing more magnetic field lines to pass through the wound first magnetic core 3. In addition, when rotating, each pair of permanent magnets 7 will receive a repulsive force, making it easier to rotate. The number of permanent magnets 7 and the first magnetic core 3 should be avoided to be the same to prevent jamming (the positions of the wound magnetic core and the permanent magnet can be interchanged). Finally, the collected induced electromotive force is converted into direct current through the rectifier 9 to charge the battery 10, ultimately realizing the collection of micro-wind energy.

[0037] As Figure 4As shown in the figure, the elastic resonance external rotary generator is similar to the elastic resonance micro-wind energy harvester. Its basic device structure consists of a wind blade 1, a housing 6, a second magnetic core 15, a permanent magnet 7, a rotor 14, a second coil 16, a rotating shaft 2, and a second elastic connector 17. The permanent magnet 7 is fixed on the rotor 14, and the second magnetic core 15 is radially arranged on the side wall of the housing 6 through the second elastic connector 17. When an external excitation disturbs the rotation of the wind blade 1, the permanent magnet 7 will be driven to rotate through the rotating shaft 2 and the rotor 14. During rotation, a relative motion 13 occurs between the permanent magnet 7 and the radially arranged second magnetic core 15, causing the magnetic flux entering the second coil 16 to change. A current is generated in the closed second coil 16, thereby generating an induced electromotive force. The function of the second elastic connector 17 is the same as that of the elastic resonance micro-wind energy harvester, thus increasing the magnetic flux change rate. (It should be noted that the number of permanent magnets and magnetic cores should have at least one that is not a factor of 360, so that the phenomenon of jamming is not likely to occur).

[0038] Assume that the numbers of the permanent magnet 7 and the second magnetic core 15 are both factors of 360, for example, both are 12. During the operation of the device, due to the limitations of manufacturing processes and assembly precision, the relative positions of the permanent magnet 7 and the second magnetic core 15 may periodically coincide completely. When this coincidence occurs, the magnetic force distribution becomes extremely uneven, which may cause the second magnetic core 15 to be subjected to excessive lateral magnetic forces, making it impossible for the second magnetic core 15 to swing normally under the restraint of the second elastic connector 17, thereby hindering the rotation of the entire device and ultimately causing jamming.

[0039] When at least one of the numbers of the permanent magnet 7 and the second magnetic core 15 is not a factor of 360, for example, the permanent magnet 7 is 11 and the second magnetic core 15 is 12. During rotation, their relative positions will not regularly coincide completely. The magnetic force distribution is always in a dynamically changing and relatively uniform state. The second magnetic core 15 can swing smoothly under the action of the second elastic connector 17, thus effectively avoiding the occurrence of jamming and ensuring the stable operation of the device and the energy harvesting efficiency.

[0040] An elastic resonance rotary energy harvesting method includes: two methods, namely micro-wind energy harvesting and external rotary power generation; among them, the elastic resonance rotary energy harvesting device includes a wind blade 1, a housing 6, a first magnetic core 3, a permanent magnet 7, a rotor 14, a first coil 4, a rotating shaft 2, a first elastic connector 5, a second magnetic core 15, a second coil 16, and a second elastic connector 17;

[0041] The micro-wind energy harvesting includes the first elastic connector 5, the first magnetic core 3, and the first coil 4 axially arranged on the bottom of the housing;

[0042] The specific steps of the micro-wind energy harvesting are as follows:

[0043] S11. When the wind energy blows the wind blade to rotate, it drives the rotating shaft to rotate, causing the push rod to push the permanent magnet to rotate;

[0044] S12. During the rotation of the permanent magnet, relative movement occurs with the axially arranged magnetic core 1, resulting in a change in the magnetic flux entering Coil 1, causing an electric current and an induced electromotive force to be generated in the closed Coil 1.

[0045] S13. The magnetic force of the permanent magnet drives the movement of magnetic core 1. Under the action of the elastic force of elastic connection member 1 and the Ampere force, magnetic core 1 swings back and forth, increasing the magnetic flux change rate and improving the power generation efficiency.

[0046] S14. The rectifier converts the induced electromotive force into direct current to charge the battery, completing the energy collection.

[0047] External rotation power generation includes a number of elastic connection members 2, 17 radially arranged on the side wall of the housing. Each elastic connection member 2, 17 is connected with a magnetic core 2, 15. The outer surface of each magnetic core 2, 15 is wound with a coil 2, 16.

[0048] The specific steps of external rotation power generation are as follows:

[0049] S21. External excitation causes the wind blade to rotate, driving the permanent magnet to rotate through the rotating shaft and the rotor.

[0050] S22. Relative movement occurs between the permanent magnet and the radially arranged magnetic core 2, changing the magnetic flux entering Coil 2. An electric current and an induced electromotive force are generated in the closed Coil 2, and the elastic connection member 2 increases the magnetic flux change rate to achieve energy collection.

[0051] The present invention forms a simple electromagnetic power generation device through a permanent magnet and a soft magnetic core wound with a coil. Among them, the permanent magnet should preferably use a super strong magnet, such as: neodymium iron boron material. The soft magnetic core should be made of a material with high magnetic permeability. For example, silicon steel (relative magnetic permeability 7000 - 10000), ferrite (about 10000), nickel - iron alloy (about 2000), manganese - zinc ferrite (300 - 5000) and permalloy (20000 - 200000). The spring sheet should use a material with a certain elastic modulus and not easily interfere with the magnetic field, such as: spring steel, stainless steel. Other rigid housings, etc. should use materials with low interference to the magnetic wire, such as aluminum alloy, plastic and other materials. The shapes of the permanent magnet and the soft magnetic core can be changed according to the application scenario, such as cylindrical, fan - shaped and strip - shaped, etc. The positions of the wound magnetic core and the permanent magnet can also be swapped according to requirements.

[0052] The present invention is for power supply of micro - miniature devices, collecting low - frequency and tiny energy. The overall size of the transposition is relatively small, and the size of a single power generation unit is about mm, a coil with about 2400 turns wound on a cylindrical core, a wire diameter of 0.01 mm, an overall resistance of about 200 Ω, and a frequency of permanent magnet movement of 10 Hz. Under these conditions, as shown in Figure 5, the open circuit voltage peak value of the elastic resonance power generation unit of a single pair of cores and magnets was measured to be 1.38 V.

[0053] Therefore, the present invention adopts the above-mentioned elastic resonance type rotation energy collection device and method, which can collect rotating, reciprocating low-frequency mechanical energy. By adding elastic devices such as spring sheets, due to Lenz's law, when the mechanical energy during external rotation is systemized, part of these mechanical energies are directly converted into induced electromotive force, and the other part is converted into elastic potential energy, and then converted into induced electromotive force through resonant swing. The permanent magnet can drive the magnetic core to swing together. The original fixed magnetic core also has a magnetic flux change rate, but under the action of the spring sheet, part of the elastic potential energy is released together, so that the magnetic flux change rate is further increased, which greatly improves the generation of induced electromotive force. When the magnetic core and the magnet resonate and swing, the end face is staggered at the maximum relative speed, so that the electromagnetic power generation efficiency can be maximized.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. An elastic resonance rotation energy harvesting device, characterized in that: It includes a shell, a fan blade is arranged on the top of the shell, the fan blade is connected to a bearing arranged inside the shell through a rotating shaft, a permanent magnet is installed between the outer ring and the inner ring of the bearing, and a portion of the rotating shaft located in the bearing is provided with a plurality of push rods, the push rods are used to push the permanent magnet in the bearing to rotate, a plurality of elastic connecting parts 1 are arranged at the inner bottom end of the shell, each of the elastic connecting parts 1 is connected to a magnetic core 1, a coil 1 is wound on the outer surface of each of the magnetic cores 1, and the coil 1 is connected to a battery management module; or a plurality of elastic connecting parts 2 are arranged on the inner side wall of the shell, each of the elastic connecting parts 2 is connected to a magnetic core 2, a coil 2 is wound on the outer surface of each of the magnetic cores 2, and the coil 2 is connected to a battery management module.

2. The elastic resonance rotation energy harvesting device according to claim 1, characterized in that: The plurality of magnetic cores are connected to the bottom end of the shell through the plurality of elastic connectors and are arranged in a ring shape.

3. The elastic resonance rotation energy harvesting device according to claim 1, characterized in that: A gap of 2-3 mm is maintained between the magnetic core 1 and the permanent magnet.

4. The elastic resonance rotation energy harvesting device according to claim 1, characterized in that: The battery management module includes a battery and a rectifier. The battery is electrically connected to the coil one or the coil two through a line, and a rectifier is installed on the line.

5. The elastic resonance rotation energy harvesting device according to claim 1, characterized in that: The length of the push rod is not greater than the radius of the bearing.

6. The elastic resonance rotation energy harvesting device according to claim 1, characterized in that: The permanent magnet is made of super strong magnet material.

7. The elastic resonance rotation energy harvesting device according to claim 1, characterized in that: The magnetic core 1 or the magnetic core 2 is made of high magnetic permeability material.

8. An elastic resonance type rotational energy collection method, applied to an elastic resonance type rotational energy collection device according to any one of claims 1 to 7, characterized in that: include: Breeze energy collection and power generation method or external rotation power generation method; The breeze energy collection and power generation method comprises an elastic connection member 1, a magnetic core 1 and a coil 1 axially arranged on the bottom of the shell; The specific steps of breeze energy collection and power generation are as follows: S11. When the wind energy blows the fan blades to rotate, the rotating shaft is driven to rotate, so that the push rod pushes the permanent magnet to rotate; S12, during the rotation process, the permanent magnet moves relative to the axially arranged magnetic core 1, causing the magnetic flux entering the coil 1 to change, so that the closed coil 1 generates current and induced electromotive force; S13. The magnetic force of the permanent magnet drives the magnetic core to move. Under the action of the elastic force of the elastic connector and the Ampere force, the magnetic core swings back and forth, increasing the rate of change of the magnetic flux and improving the power generation efficiency. S14, converting the current generated by coil 1 into direct current through a rectifier to charge the battery and complete energy collection; or, The external rotating power generation method includes a plurality of elastic connectors 2 radially arranged on the side wall of the housing, each of which is connected to a magnetic core 2, and each of which is wound with a coil 2 on the outer surface; The specific steps of external rotation power generation are as follows: S21, external excitation causes the fan blade to rotate, and the push rod on the shaft drives the permanent magnet to rotate; S22, the permanent magnet and the magnetic core 2 radially arranged on the inner side wall of the shell move relative to each other, so that the magnetic flux entering the coil 2 changes, the closed coil 2 generates current and induced electromotive force, and the elastic connecting part 2 increases the rate of change of the magnetic flux to achieve energy collection.

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