An energy harvesting device for harvesting wave energy

Abstract

The application relates to the technical field of energy collection, in particular to an energy collection device for collecting wave energy. The energy collection device comprises at least two waterproof housings, any two adjacent housings are rotationally connected, and a plurality of friction nanogenerators are arranged in the housings. The friction nanogenerator comprises an outer shell and a plurality of insulating balls arranged in the outer shell. In a first direction, the outer shell comprises a first conductive part, an insulating part and a second conductive part which are sequentially connected, and the insulating part is used for isolating the first conductive part and the second conductive part. The plurality of insulating balls are arranged in the first direction and can roll in the first direction. The insulating balls and the first conductive part and the second conductive part have different electron gaining and losing abilities. The density of the energy collection device is less than the density of seawater, the energy collection device does not need to be fixed and can be directly placed on the sea surface, has the advantages of low installation, operation and maintenance costs, and the insulating balls can roll along the wave propagation direction, so that the ocean fluctuation energy can be efficiently collected.

Description

Technical Field

[0001] This application relates to the field of energy harvesting technology, and in particular to an energy harvesting device for harvesting wave energy. Background Technology

[0002] Since Professor Wang Zhonglin proposed the concept of "blue energy" in 2014, he has conducted in-depth research on the enormous energy contained in ocean wave fluctuations, namely "wave energy." China has a coastline of over 18,000 kilometers and more than 6,960 islands of varying sizes, all of which contain abundant "blue energy." However, due to various factors, these resources have not yet been formally developed.

[0003] First, wave energy has a low and irregular frequency, typically less than 5Hz, which limits the application of traditional electromagnetic power generation technology, making it unable to effectively collect this low-frequency and irregular energy. Second, the installation requirements for electromagnetic power generation equipment in the ocean are high, necessitating raising it above sea level, fixing it at a specific depth, or submerging it directly on the seabed. This not only increases the cost of harvesting wave energy but also places a huge burden on subsequent maintenance. More importantly, this approach is not suitable for large-scale deployment, and no breakthrough has yet been achieved in large-scale implementation. These factors combined have resulted in the ineffective development of the abundant "blue energy" resources, leading to a waste of resources. Summary of the Invention

[0004] This application discloses an energy harvesting device for collecting wave energy, which enables efficient collection of ocean wave energy and is suitable for widespread application.

[0005] To achieve the above objectives, this application provides the following technical solution:

[0006] In a first aspect, this application provides an energy harvesting device for collecting wave energy. The device includes at least two waterproof housings, rotatably connected to any two adjacent housings. Multiple triboelectric nanogenerators are disposed within the housings. Each triboelectric nanogenerator includes a shell and multiple insulating spheres disposed within the shells. Along a first direction, the shell includes a first conductive portion, an insulating portion, and a second conductive portion connected sequentially, with the insulating portion is used to isolate the first and second conductive portions. The multiple insulating spheres are arranged along the first direction and are capable of rolling along the first direction. The insulating spheres have different abilities to gain or lose electrons with the first conductive portion and with the second conductive portion. The density of the energy harvesting device is less than the density of seawater.

[0007] The energy harvesting device described above has a density less than that of seawater, allowing it to float directly on the sea surface and oscillate with the waves. The insulating sphere inside the triboelectric nanogenerator, vibrating under these conditions, rolls along a first direction. This rolling friction occurs between the insulating sphere and the first and second conductive parts, and the ability of the insulating sphere to gain or lose electrons differs between the two. Due to the triboelectric effect, charge transfers between the insulating sphere and the first and second conductive parts, and between the insulating sphere and the second conductive part. The first and second conductive parts are isolated by the insulating part, allowing them to function as the first and second electrodes, respectively. Due to electrostatic induction governed by Maxwell's displacement current, an alternating current is generated between the first and second electrodes. The energy harvesting device in this application features a unique structural design, requiring no fixing and can be directly placed on the sea surface, offering advantages such as low installation, operation, and maintenance costs. Furthermore, the insulating sphere inside the triboelectric nanogenerator can roll along the wave propagation direction, effectively controlling its floating and undulating attitude, thereby achieving efficient harvesting of ocean wave energy.

[0008] Furthermore, along the first direction, elastic elements are provided at both ends of the housing, which are used to cause the multiple insulating balls to roll in opposite directions after being squeezed by the multiple insulating balls.

[0009] Furthermore, the area of ​​the insulating portion accounts for 5.6%-86.8% of the area of ​​the outer casing.

[0010] Furthermore, the insulating portion, the first conductive portion, and the second conductive portion are arranged to form a cavity, and a plurality of insulating spheres are located within the cavity. The ratio of the sum of the diameters of the plurality of insulating spheres to the length of the cavity along the first direction is 5%-93%.

[0011] Furthermore, the outer shell is fabricated using 3D printing technology; and / or, the material used to fabricate the outer shell is an organic polymer.

[0012] Furthermore, multiple triboelectric nanogenerators are stacked to form a power generation unit; any number of power generation units are combined and distributed in a grid pattern.

[0013] Furthermore, the power generation unit includes a first wiring portion and a second wiring portion for connecting to a wire. The first wiring portion is electrically connected to a plurality of first conductive portions, and the second wiring portion is electrically connected to a plurality of second conductive portions.

[0014] Furthermore, any two adjacent housings are connected by a bearing structure.

[0015] Furthermore, the energy harvesting device also includes a rectifier module and a circuit management module. Both the rectifier module and the circuit management module are electrically connected to the triboelectric nanogenerator. The rectifier module is used to convert the alternating current generated by the triboelectric nanogenerator into direct current and send it to the circuit management module. The circuit management module is used to manage and store the electrical energy generated by the triboelectric nanogenerator.

[0016] Furthermore, the circuit management module includes an input capacitor, a SCR switch, an output capacitor, an inductor, a Zener diode, and a freewheeling diode. The first terminal of the input capacitor is connected to the first output terminal of the rectifier module, the cathode of the Zener diode, and the first terminal of the SCR switch. The second terminal of the input capacitor is connected to the second output terminal of the rectifier module, the anode of the freewheeling diode, and the second terminal of the output capacitor. The second terminal of the SCR switch is connected to the cathode of the freewheeling diode. The cathode of the Zener diode is connected to the first terminal of the SCR switch, and the anode of the Zener diode is connected to the second terminal of the SCR switch. The first terminal of the inductor is connected to the second terminal of the SCR and the cathode of the freewheeling diode. The second terminal of the inductor is connected to the first terminal of the output capacitor, and the second terminal of the output capacitor is connected to the anode of the freewheeling diode. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of an energy harvesting device according to an embodiment of this application;

[0018] Figure 2 This is a schematic diagram of the structure of a triboelectric nanogenerator according to an embodiment of this application;

[0019] Figure 3 This is a schematic diagram illustrating the state of an energy harvesting device according to an embodiment of this application under different wave sizes.

[0020] Figure 4 This is a schematic diagram of the elastic element in a triboelectric nanogenerator in different states according to another embodiment of this application;

[0021] Figure 5 This is a schematic diagram illustrating the working principle of a triboelectric nanogenerator according to an embodiment of this application;

[0022] Figure 6 This is a potential simulation diagram of a triboelectric nanogenerator according to another embodiment of this application;

[0023] Figure 7 This is a schematic diagram of the structure of a power generation unit according to an embodiment of this application;

[0024] Figure 8 This is a partial cross-sectional view of a power generation unit according to an embodiment of this application;

[0025] Figure 9 This is a schematic diagram of the integration of four power generation units according to one embodiment of this application;

[0026] Figure 10 This is a circuit control schematic diagram of an energy harvesting device according to an embodiment of this application;

[0027] Figure 11 This is a test diagram of the energy storage performance of a power generation unit according to one embodiment of this application.

[0028] Reference numerals: 100-Housing; 110-Main structure; 120-Top cover; 200-Bearing structure; 210-Rotating shaft; 220-First connector; 230-Second connector; 300-Power generation unit; 310-First wiring part; 320-Second wiring part; 400-Triboelectric nanogenerator; 410-Housing shell; 411-First conductive part; 412-Insulating part; 413-Second conductive part; 420-Insulating ball; 430-Elastic element; 500-Rectifier module; 510-Full-wave rectifier circuit rectifier bridge; 600-Circuit management module; 610-Input capacitor; 620-SCR switch; 630-Output capacitor; 640-Inductor; 650-Zenith diode; 660-Freewheeling diode; 700-Load;

[0029] 01-Cavity. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] The application scenarios described in this application are for the purpose of more clearly illustrating the technical solutions of this application, and do not constitute a limitation on the technical solutions provided in this application. Those skilled in the art will understand that with the emergence of new application scenarios, the technical solutions provided in this application are also applicable to similar technical problems. In the description of this application, unless otherwise stated, "multiple" means two or more.

[0032] China's coastline stretches over 18,000 kilometers, containing extremely rich wave energy. However, wave energy conversion technologies (WECs) are still immature and face many technical challenges. These include designing equipment capable of long-term stable operation in harsh marine environments and improving energy conversion efficiency.

[0033] Traditional electromagnetic power generation technology is extremely costly to convert wave energy into electricity in low-frequency, irregular marine environments. The complex marine environment places very high demands on its installation, operation, maintenance, and energy conversion efficiency. To date, no one has ventured into large-scale promotion in this field, resulting in the undeveloped and wasted potential of "blue energy," which contains extremely rich energy resources.

[0034] In view of this, this application provides an energy harvesting device for collecting wave energy. Figure 1 This is a schematic diagram of the structure of an energy harvesting device according to an embodiment of this application. Figure 2 This is a schematic diagram of the structure of a triboelectric nanogenerator according to an embodiment of this application. Please refer to... Figure 1 and Figure 2 The energy harvesting device includes at least two waterproof housings 100, which are rotatably connected to any two adjacent housings 100. Multiple triboelectric nanogenerators 400 are disposed within each housing 100. Each triboelectric nanogenerator 400 includes a shell 410 and multiple insulating spheres 420 disposed within the shell 410. Along a first direction D1, the shell 410 includes a first conductive portion 411, an insulating portion 412, and a second conductive portion 413 connected in sequence. The insulating portion 412 isolates the first conductive portion 411 and the second conductive portion 413. The first conductive portion 411, the insulating portion 412, and the second conductive portion 413 enclose a closed chamber 01. Within the chamber 01, the multiple insulating spheres 420 are arranged along the first direction and can roll along the first direction D1. The insulating spheres 420 have different abilities to gain or lose electrons with the first conductive portion 411 and with the second conductive portion 413. The density of the energy harvesting device is less than that of seawater, allowing the energy harvesting device to float on the sea surface and oscillate arbitrarily with the direction of wave propagation.

[0035] The housing 100 may include a main structure 110 and a top cover 120, which together form a closed cavity. Multiple triboelectric nanogenerators 400 are disposed within this cavity.

[0036] It is understood that this application does not limit the number of shells 100; they can be two, three, or more, depending on actual needs.

[0037] The housing 100 can be made of inexpensive, high-strength, and corrosion-resistant materials, such as aluminum alloy. Optionally, the housing 100 and the multiple triboelectric nanogenerators 400 can be detachably connected to each other to facilitate the replacement or repair of any of the triboelectric nanogenerators 400, so that the triboelectric nanogenerators 400 can continuously and efficiently provide electrical output performance.

[0038] It should be noted that when the housing 100 is made of conductive material, the triboelectric nanogenerator 400 needs to be insulated from the housing 100. Specifically, an insulating layer can be provided between the two.

[0039] In some embodiments of this application, any two adjacent housings 100 are connected by a connecting component, which may be made of high-strength, corrosion-resistant metals or alloys, such as stainless steel, aluminum alloy, magnesium alloy, etc.

[0040] In some embodiments of this application, the area of ​​the insulating portion accounts for 5.6%-86.8% of the area of ​​the outer shell. If the area of ​​the insulating portion is too small, the spacing between the conductive portions will be too small, which may easily lead to electrostatic breakdown due to excessive electric field strength and loss of charge; if the area of ​​the insulating portion is too large, the rolling time of the insulating ball will increase, which may result in the charge being dissipated before it is completely transferred.

[0041] Preferably, the ratio of the insulating portion to the total area of ​​the outer shell is 11.3-18.9%. Within this range, it can be ensured that the insulating portion can effectively suppress breakdown without hindering the efficient transfer of charge, while adapting to the dielectric properties of the material and the motion dynamics of the ball, thereby maximizing the triboelectric power generation efficiency.

[0042] In some embodiments of this application, the insulating portion, the first conductive portion, and the second conductive portion enclose a cavity, and a plurality of insulating spheres are located within the cavity. The ratio of the sum of the diameters of the plurality of insulating spheres to the length of the cavity along the first direction is 5%-93% to balance the efficiency of charge generation and transfer. If the number of insulating spheres is too small (less than 5%), the contact area is insufficient, the triboelectric effect is weak, and the amount of charge generated is low. If the number of insulating spheres is too large (more than 93%), the movement of the insulating spheres is restricted, making it difficult for them to roll sufficiently between the insulating and conductive portions, thus hindering charge separation and transfer.

[0043] Preferably, the ratio of the sum of the diameters of the multiple insulating spheres to the length of the chamber along the first direction is 31%-46%, which can both cover a sufficient contact area to maximize triboelectric charging and allow free movement to efficiently transfer charge.

[0044] Continue to refer to Figure 1 Any two adjacent housings 100 are connected by a bearing structure 200 to reduce resistance during relative rotation. Specifically, the bearing structure 200 includes a rotating shaft 210, a first connecting member 220, and a second connecting member 230. One of the two adjacent housings 100 is fixedly connected to the first connecting member 220, and the other is fixedly connected to the second connecting member 230. The rotating shaft 210 passes through the first connecting member 220 and the second connecting member 230, and both the first connecting member 220 and the second connecting member 230 can rotate around the rotating shaft 210.

[0045] In some embodiments of this application, at least two housings 100 may be arranged in one direction. Figure 3 This is a schematic diagram illustrating the state of an energy harvesting device according to an embodiment of this application under different wave sizes, as shown below. Figure 3 As shown, any two adjacent shells 100 are rotatably connected so that the included angle between any two adjacent shells 100 can change with the size of the waves, thereby changing the included angle between the shell 100 and the horizontal plane. This causes the insulating ball 420 in the triboelectric nanogenerator 400 inside the shell 100 to roll back and forth. The insulating ball 420 rolls and rubs against the first conductive part 411, the insulating part 412, and the second conductive part 413, forming a freestanding rollmode triboelectric nanogenerator 400. It generates charges through triboelectric charging and electrostatic induction and separates the charges, driving the electrons in the external circuit to move in a directional manner, thereby collecting wave energy and converting it into electrical energy.

[0046] Figure 4 This is a schematic diagram of the structure of a triboelectric nanogenerator according to another embodiment of this application. Along the first direction, elastic members 430 are provided at both ends of the outer shell 410. The elastic members 430 are used to make the multiple insulating balls 420 roll in opposite directions after being squeezed by multiple insulating balls 420, thereby forming a spring oscillator structure, so that the multiple insulating balls 420 can perform periodic reciprocating motion along the first direction, significantly enhancing the motion frequency of the insulating balls 420.

[0047] Because the elastic element 430 provides the driving force for the reciprocating motion of the multiple insulating balls 420, and by utilizing the rhythm of the waves, the entire energy harvesting device can form a resonant structure that can store and release energy. This allows the multiple insulating balls 420 to continue reciprocating in the first direction for a period of time, even if the wave fluctuations weaken. Without the elastic element 430, the multiple insulating balls 420 may not be able to effectively return to their original position after being pushed by the waves in one direction, resulting in discontinuous energy harvesting. However, with the elastic element 430 added, the multiple insulating balls 420 are pushed back to their original position or in the opposite direction by the elastic element 430 after being pushed by the waves, forming a periodic reciprocating motion. This significantly enhances the motion frequency of the insulating balls 420, greatly improving the frequency of friction and the stability and continuity of the electrical output.

[0048] In some embodiments of this application, the elastic element 430 may be a spring, a metal sheet, or the like.

[0049] It should be noted that the first direction D1 refers to the direction of the line connecting the first conductive part 411 and the second conductive part 413. As the waves oscillate, the arrangement direction of at least two shells 100 will change. Therefore, the first direction is not fixed and will also change accordingly.

[0050] In some embodiments of this application, the outer shell 410 is fabricated using 3D printing technology, thereby enabling customized and integrated fabrication according to the design.

[0051] In some embodiments of this application, the material used to prepare the outer shell 410 can be an organic polymer, which has advantages such as low cost, light weight, moisture resistance, corrosion resistance, no need for complex support structure, and long service life.

[0052] For example, the outer shell 410 is made of polylactic acid (PLA), which has the advantages of low cost, easy floating, biodegradability, and 3D printing capability. It is understood that both the first conductive portion 411 and the second conductive portion 413 can be made of conductive PLA, and both insulating portions 412 can be made of insulating PLA.

[0053] In some embodiments of this application, the insulating ball 420 may be made of polytetrafluoroethylene (PTFE) material, which can not only reduce frictional resistance, but also increase the output performance of the triboelectric nanogenerator 400.

[0054] The structure of the triboelectric nanogenerator 400 has been introduced above. The working process and principle of the triboelectric nanogenerator 400 are explained below with reference to the accompanying drawings.

[0055] Figure 5 This is a schematic diagram illustrating the working principle of a triboelectric nanogenerator according to an embodiment of this application, as shown below. Figure 5As shown, the insulating ball 420 rolls back and forth in the first direction within the chamber 01. When the insulating ball 420 comes into contact with the first conductive portion 411 or the second conductive portion 413, an induced charge is generated. Assuming the electronegativity of the insulating ball 420 is greater than that of the first conductive portion 411 and the second conductive portion 413, the insulating ball 420 readily gains electrons and becomes negatively charged, while the first conductive portion 411 and the second conductive portion 413 lose electrons. In Figure (i), the first conductive portion 411 displays a positive charge equal to the negative charge of the multiple insulating balls 420. When the insulating ball 420 moves to the position shown in Figure (ii), the multiple insulating balls 420 retain a large amount of negative charge. When the multiple insulating balls 420 come into contact with the second conductive portion 413, current is transferred from the second conductive portion 413 to the first conductive portion 411 through the external circuit, balancing the potential difference with the multiple insulating balls 420. When the plurality of insulating spheres 420 are in the position shown in Figure (iii), the amount of positive charge accumulated on the second conductive portion 413 is equal to the amount of negative charge carried by the plurality of insulating spheres 420. Similarly, as shown in Figure (iv), when the plurality of insulating spheres 420 move back under wave excitation, an external current is generated from the first conductive portion 411 to the second conductive portion 413. In actual cycling, the outer casing 410 of the triboelectric nanogenerator 400 continuously shakes, generating alternating current output in the external circuit.

[0056] Figure 6 Here is a simulation diagram of the potential of a triboelectric nanogenerator according to another embodiment of this application, with reference to... Figure 6 When the potential of the triboelectric nanogenerator 400 was simulated using COMSOL software, the change of potential as the insulating ball 420 moved was simulated, which further verified the working principle mentioned above.

[0057] Figure 7 This is a schematic diagram of the structure of a power generation unit according to an embodiment of this application. Figure 8 This is a partial cross-sectional view of a power generation unit according to an embodiment of this application, with reference to... Figure 7 and Figure 8 Multiple triboelectric nanogenerators 400 are stacked to form a power generation unit 300. The power generation unit 300 includes multiple triboelectric nanogenerators 400, which can significantly increase the output power.

[0058] Multiple triboelectric nanogenerators 400 can be stacked and 3D printed as a single unit.

[0059] Reference Figure 7The power generation unit 300 includes a first wiring portion 310 and a second wiring portion 320 for connection with a wire. The first wiring portion 310 is electrically connected to a plurality of first conductive portions 411, and the second wiring portion 320 is electrically connected to a plurality of second conductive portions 413. The first wiring portion 310 and the second wiring portion 320 are electrically connected to an external load to realize the output of electrical energy.

[0060] Among them, the multiple outer shells 410 of the power generation unit 300 can be 3D printed integral structures.

[0061] Optionally, the first wiring portion 310 and the outer shell 410 are integrally formed and can be manufactured using 3D printing technology. Similarly, the second wiring portion 320 and the outer shell 410 are integrally formed and can be manufactured using 3D printing technology.

[0062] It is understandable that any one of the power generation units 300 can work independently, or any number of power generation units 300 can be combined together and distributed in a grid pattern. The steps of combining or separating multiple power generation units 300 are simple and save time and effort.

[0063] Figure 9 This is a schematic diagram of the integration of four power generation units according to one embodiment of this application, as shown below. Figure 9 As shown, in one possible embodiment, the energy harvesting device has 28 power generation units 300 inside a housing 100, specifically arranged in a 2-layer, 2-column layout. That is, in the height direction, each column includes 2 power generation units 300, and each layer structure includes 14 parallel power generation units 300. Each power generation unit 300 is equidistant from its adjacent power generation units 300 in both the horizontal and vertical directions, forming a neat matrix layout.

[0064] It is understood that the number of power generation units 300 included within the housing 100 can be set according to the output power requirements to meet the needs of different customer groups. The energy harvesting device in this application may include a small number of power generation units 300, covering a small marine area to meet the needs of individuals or households; the energy harvesting device in this application may also include multiple power generation units 300, covering a wide marine area. After the aforementioned power generation units 300 are connected to the grid, it is expected to transmit the electricity to the national grid.

[0065] Figure 10 This is a circuit control schematic diagram of an energy harvesting device according to an embodiment of this application, such as... Figure 10As shown, the energy harvesting device also includes a rectifier module 500 and a circuit management module 600. Both the rectifier module 500 and the circuit management module 600 are electrically connected to the multiple triboelectric nanogenerators 400 in the power generation unit 300. The rectifier module 500 is used to convert the alternating current generated by the triboelectric nanogenerators 400 into direct current and send it to the circuit management module 600. The circuit management module 600 is used to manage and store the electrical energy generated by the triboelectric nanogenerators 400.

[0066] In some embodiments of this application, the rectifier module 500 may be a full-wave rectifier circuit rectifier bridge 510.

[0067] In some embodiments of this application, the circuit management module 600 includes an input capacitor 610, a silicon controlled rectifier (SCR) switch 620, an output capacitor 630, an inductor 640, a Zener diode 650, and a freewheeling diode 660. The first terminal of the input capacitor 610 is connected to the first output terminal of the rectifier module 500, the cathode of the Zener diode 650, and the first terminal of the SCR switch 620. The second terminal of the input capacitor 610 is connected to the second output terminal of the rectifier module 500, the anode of the freewheeling diode 660, and the first terminal of the output capacitor 630. The two terminals are connected as follows: the second terminal of the SCR switch 620 is connected to the negative terminal of the freewheeling diode 660; the negative terminal of the Zener diode 650 is connected to the first terminal of the SCR switch 620; the positive terminal of the Zener diode 650 is connected to the second terminal of the SCR switch 620; the first terminal of the inductor 640 is connected to both the second terminal of the SCR switch 620 and the negative terminal of the freewheeling diode 660; the second terminal of the inductor 640 is connected to the first terminal of the output capacitor 630; and the second terminal of the output capacitor 630 is connected to the positive terminal of the freewheeling diode 660.

[0068] Among them, the input capacitor 610 can be a ceramic capacitor. Ceramic capacitors can be made very small, which is suitable for high-density integrated circuit applications. Moreover, ceramic materials have good thermal and chemical stability, which allows ceramic capacitors to maintain relatively stable electrical parameters in various environments.

[0069] In some embodiments of this application, the circuit management module 600 is electrically connected to the load 700 to provide power to the load 700, wherein the load 700 may be a sensor or other electrical device.

[0070] The structure of the circuit management module has been described above. The energy transfer process between the power generation unit 300 and the subsequent load 700 is explained below:

[0071] Phase 1: The energy collected by the triboelectric nanogenerator 400 flows to the input capacitor 610. During this phase, the subsequent SCR switch 620 is not connected. At this time, the input capacitor 610 is the only load of the triboelectric nanogenerator 400. There are no other unnecessary electronic components to consume energy, and the voltage across the input capacitor 610 can quickly rise to its maximum value.

[0072] In the second stage, Zener diode 650 is connected across the SCR switch 620, acting as the switch that triggers the SCR switch 620 to close. When the voltage across the input capacitor 610 exceeds the threshold voltage of Zener diode 650, Zener diode 650 conducts, and the current in the input capacitor 610 flows to the control terminal of the SCR switch 620. Simultaneously, the first and second terminals of the SCR switch 620 conduct, and energy enters the next stage. Energy in the input capacitor 610 is transferred to the inductor 640, the output capacitor 630, and the load 700. This stage ends when the energy in the input capacitor 610 is completely depleted. In the next cycle, when the voltage across the input capacitor 610 exceeds the voltage across Zener diode 650, the SCR switch 620 restarts, and this cycle repeats.

[0073] The third stage: The freewheeling diode 660 begins to conduct. At this time, the inductor 640 transfers its stored energy to the output capacitor 630 and the load 700. Simultaneously, the current in the inductor 640 decreases. This stage ends when the current in the inductor 640 decreases to zero. This means that in this stage, all the energy in the inductor 640 is transferred to the output capacitor 630 and the load 700. At the end of the third stage, the freewheeling diode 660 stops conducting.

[0074] Fourth stage: Energy is transferred from the output capacitor 630 to the load 700. During this stage, all other electronic components are not conducting.

[0075] Through the combined action of these four stages, the circuit management module 600 achieves efficient energy transfer and storage. In each stage, carefully designed electronic components and circuits ensure maximum energy utilization, thereby improving the energy efficiency of the entire energy harvesting device.

[0076] In some embodiments of this application, the circuit management module and the rectifier module may be fixed inside the housing 100.

[0077] The energy harvesting device of this application will now be described with reference to specific embodiments.

[0078] Example 1

[0079] Example 1 provides an energy harvesting device, referring to Figure 1 and Figure 2 The energy harvesting device comprises two rotatably connected housings 100, each housing measuring 60×60×18cm with a wall thickness of 4mm. Each housing 100 contains four power generation units 300, each measuring 28×8×8cm (length×width×height). The sides of each power generation unit 300 have a first wiring portion 310 and a second wiring portion 320 for connection to wires. Each power generation unit 300 includes 598 triboelectric nanogenerators 400, arranged in a 46×13 (length×height) array. The dimensions of each layer of triboelectric nanogenerators 400 are chambers 01, each measuring 5×5×77mm (length×height×width). Each chamber 01 of each layer contains multiple PTFE spheres. The diameter of the PTFE spheres is 1-4mm, depending on actual needs, but cannot exceed the height of the chamber 01 (5mm), preferably 4mm. The number of PTFE balls is 1-19, preferably 7. The diameter of the PTFE balls will affect the number of PTFE balls. The total width of chamber 01 is 77mm. The number of PTFE balls × diameter must be less than 77mm.

[0080] like Figure 10 As shown, the energy harvesting device also includes a rectifier module 500 and a circuit management module 600. Both the rectifier module 500 and the circuit management module 600 are electrically connected to the multiple triboelectric nanogenerators 400 in the power generation unit 300. The rectifier module 500 is used to convert the alternating current generated by the triboelectric nanogenerators 400 into direct current and send it to the circuit management module 600. The circuit management module 600 is used to manage and store the electrical energy generated by the triboelectric nanogenerators 400.

[0081] Among them, the energy storage performance of the power generation unit was tested when the diameter of the PTFE spheres was 4mm and the number of PTFE spheres was 7. Figure 11 This is a test diagram of the energy storage performance of a power generation unit according to an embodiment of this application, as shown. Figure 11 As shown, the load 700 is powered by an energy harvesting device. When the energy harvesting device includes a rectifier module 500, the power generation unit 300 needs about 3000 seconds to bring the voltage across the load 700 to 4V. When the energy harvesting device includes a rectifier module 500 and a circuit management module 600, the power generation unit 300 needs about 500 seconds to bring the voltage across the load 700 to 4V. Compared to including only the rectifier module 500, the charging capacity of the power generation unit 300 is increased by nearly 6 times, ensuring maximum energy utilization and thus improving the energy efficiency of the entire energy harvesting device.

[0082] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An energy harvesting device for collecting wave energy, characterized in that, The energy harvesting device includes at least two waterproof housings, which are rotatably connected to any two adjacent housings, and multiple triboelectric nanogenerators are installed inside the housings. The triboelectric nanogenerator includes a housing and a plurality of insulating spheres disposed within the housing. Along a first direction, the housing includes a first conductive portion, an insulating portion, and a second conductive portion connected in sequence. The insulating portion is used to isolate the first conductive portion and the second conductive portion. The plurality of insulating spheres are arranged along the first direction and can roll along the first direction. The ability of each insulating sphere to gain or lose electrons is different from that of the first conductive portion and the second conductive portion. The density of the energy harvesting device is less than that of seawater.

2. The energy harvesting device according to claim 1, characterized in that, Along the first direction, elastic elements are provided at both ends of the outer shell, and the elastic elements are used to cause the plurality of insulating balls to roll in the opposite direction after being squeezed by the plurality of insulating balls.

3. The energy harvesting device according to claim 1, characterized in that, The area of ​​the insulating portion accounts for 5.6% to 86.8% of the area of ​​the outer casing.

4. The energy harvesting device according to claim 1, characterized in that, The insulating portion, the first conductive portion, and the second conductive portion are arranged to form a cavity, and the plurality of insulating spheres are located within the cavity. The ratio of the sum of the diameters of the plurality of insulating spheres to the length of the cavity along the first direction is 5%-93%.

5. The energy harvesting device according to claim 1, characterized in that, The outer shell is manufactured using 3D printing technology; and / or, The outer shell is made of an organic polymer.

6. The energy harvesting device according to any one of claims 1-5, characterized in that, The multiple triboelectric nanogenerators are stacked to form a power generation unit; Any number of the power generation units are combined and distributed in a grid pattern.

7. The energy harvesting device according to claim 6, characterized in that, The power generation unit includes a first terminal and a second terminal for connecting to a conductor. The first terminal is electrically connected to a plurality of first conductive parts, and the second terminal is electrically connected to a plurality of second conductive parts.

8. The energy harvesting device according to any one of claims 1-5, characterized in that, The adjacent housings are connected by a bearing structure.

9. The energy harvesting device according to any one of claims 1-5, characterized in that, The energy harvesting device further includes a rectifier module and a circuit management module. Both the rectifier module and the circuit management module are electrically connected to the triboelectric nanogenerator. The rectifier module is used to convert the alternating current generated by the triboelectric nanogenerator into direct current and send it to the circuit management module. The circuit management module is used to manage and store the electrical energy generated by the triboelectric nanogenerator.

10. The energy harvesting device according to claim 9, characterized in that, The circuit management module includes an input capacitor, a SCR switch, an output capacitor, an inductor, a Zener diode, and a freewheeling diode. The first terminal of the input capacitor is connected to the first output terminal of the rectifier module, the cathode of the Zener diode, and the first terminal of the SCR switch. The second terminal of the input capacitor is connected to the second output terminal of the rectifier module, the anode of the freewheeling diode, and the second terminal of the output capacitor. The second terminal of the SCR switch is connected to the cathode of the freewheeling diode. The cathode of the Zener diode is connected to the first terminal of the SCR switch, and the anode of the Zener diode is connected to the second terminal of the SCR switch. The first terminal of the inductor is connected to the second terminal of the SCR and the cathode of the freewheeling diode. The second terminal of the inductor is connected to the first terminal of the output capacitor, and the second terminal of the output capacitor is connected to the anode of the freewheeling diode.

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