An electromagnetic-piezoelectric hybrid low-speed wind energy capture and power generation system

Abstract

The present invention discloses an electromagnetic-piezoelectric hybrid low wind speed energy capture and power generation system. The energy capture and power generation system includes a fixed frame, a plurality of flexible ropes and a plurality of energy capture devices. The top surface of the fixed frame is installed at an external fixed position, and the bottom surface of the fixed frame is evenly spaced along the circumference. The upper end of each flexible rope is installed on the bottom surface of the fixed frame, and the lower end of each flexible rope is connected to an energy capture device; each energy capture unit is coaxially connected and arranged in sequence from top to bottom, and the end cover is installed on the top surface of the uppermost energy capture unit; the lower end of each flexible rope is connected to the center of an end cover below. The present invention uses an electromagnetic-piezoelectric hybrid method to capture wind energy at low wind speeds, thereby reducing the minimum wind speed for wind energy utilization. The energy capture device can be arrayed according to actual conditions and has good environmental adaptability. The energy capture system can maximize the utilization of wind energy, thereby improving the overall power generation and wind energy utilization efficiency of the system.

Description

Technical Field

[0001] This invention relates to an energy capture and power generation system, specifically to an electromagnetic-piezoelectric hybrid low-wind-speed energy capture and power generation system. Background Technology

[0002] Wind energy, as a clean and renewable energy source, is receiving increasing attention worldwide. For coastal islands, grassland pastoral areas, mountainous regions, and plateaus lacking water, fuel, and with inconvenient transportation, the application of wind power generation, tailored to local conditions, holds immense promise. Currently, the focus of wind power application and research is on large-scale wind turbine grid-connected power generation, utilizing mostly high-speed wind energy. Small-scale, easily integrated, low-power, continuous power generation devices are relatively scarce. Therefore, designing micro-energy supply solutions that can collect and convert low-speed wind energy into electricity is highly valuable.

[0003] Based on existing findings and research, the theory and application of electromagnetic power generation technology are already quite mature. With the development of piezoelectric materials, it has been discovered that these materials can deform under mechanical force to convert mechanical energy into electrical energy, achieving a high energy density. Piezoelectric materials also possess advantages such as low cost, simple structure, and ease of processing. However, piezoelectric power generation has disadvantages including high internal resistance and relatively small current output. Electromagnetic power generation requires high operating frequencies, and using only one method results in a significant amount of residual energy not being collected, leading to low power generation efficiency. Summary of the Invention

[0004] To address the problems existing in the background technology, and to fully utilize wind energy resources under low wind speed conditions and improve wind energy capture efficiency, this invention combines electromagnetic power generation and piezoelectric power generation to design an electromagnetic-piezoelectric hybrid low wind speed energy capture and power generation system. This system can effectively capture low wind speed wind energy, and the energy capture system composed of energy capture devices can maximize wind energy capture based on the vortex-induced oscillation effect, thereby increasing the system's power generation.

[0005] The technical solution adopted in this invention is:

[0006] The low-wind-speed energy harvesting and power generation system of the present invention includes a fixed frame, several flexible ropes and several energy harvesting devices. The top surface of the fixed frame is installed at an external fixed point, and several flexible ropes are evenly spaced along the circumference on the bottom surface of the fixed frame. The upper end of each flexible rope is installed on the bottom surface of the fixed frame, and the lower end of each flexible rope is connected to an energy harvesting device.

[0007] The energy harvesting device includes end caps and several energy harvesting units, which are arranged coaxially from top to bottom. The end caps are installed on the top surface of the uppermost energy harvesting unit; the lower end of each flexible rope is connected to the center of an end cap below. The array-arranged energy harvesting device can maximize the capture of wind energy based on the vortex-induced oscillation effect, thereby increasing the power generation of the energy harvesting power generation system.

[0008] The energy harvesting unit includes a piezoelectric layer, a magnetic sphere layer, and a coil layer arranged coaxially from top to bottom. Each piezoelectric layer, magnetic sphere layer, and coil layer includes a single-layer shell, which is cylindrical. The single-layer shells are arranged coaxially and threadedly from top to bottom. The single-layer shells are made of non-metallic materials.

[0009] The piezoelectric layer also includes several L-shaped fasteners, several piezoelectric sheets, and several magnets. Each piezoelectric sheet is evenly spaced along the circumference on the inner wall of the single-layer shell of the piezoelectric layer and does not contact each other. One end of each piezoelectric sheet is fixed to the inner wall of the single-layer shell of the piezoelectric layer by an L-shaped fastener, and the other end of each piezoelectric sheet faces the center of the single-layer shell of the piezoelectric layer. A magnet is installed on the upper side of the other end of each piezoelectric sheet.

[0010] The magnetic sphere layer also includes magnetic spheres, which are placed inside the monolayer shell of the magnetic sphere layer and are not fixed to the monolayer shell.

[0011] The coil layer also includes several coils, which are evenly spaced circumferentially on the inner bottom surface of the single-layer shell of the coil layer. The coils do not contact each other and do not contact the inner wall surface of the single-layer shell of the coil layer.

[0012] Each piezoelectric element of the piezoelectric layer is parallel to the bottom surface of the single-layer shell; the number of piezoelectric elements, the number of L-shaped fasteners, and the number of magnets in the piezoelectric layer are equal.

[0013] The piezoelectric element is made of piezoelectric ceramic PZT material.

[0014] In the piezoelectric layer, the magnetic poles of two adjacent magnets that are close to each other are the same, and their magnetic repulsion makes them easy to oscillate.

[0015] The axial direction of each coil in the coil layer is perpendicular to the bottom surface of the single-layer shell.

[0016] In the described energy harvesting and power generation system, under the influence of a natural breeze, each energy harvesting device oscillates with the wind under the traction of flexible ropes. This causes each energy harvesting unit to move its magnetic spheres within the single-layer shell of the coil layer. This changes the magnetic field around the magnetic spheres, causing the magnets within the piezoelectric layer to vibrate. The piezoelectric elements then vibrate, converting the mechanical energy of the vibrations into electrical energy based on the piezoelectric effect. Simultaneously, the change in the magnetic field causes a change in the magnetic flux of each coil within the coil layer, which in turn converts wind energy into electrical energy through electromagnetic induction. Each piezoelectric element is electrically connected to an external rectifier and optimization circuit, which in turn connects to an external energy storage device or external circuit. Each coil is also electrically connected to an external energy storage device or external circuit, thus realizing the transmission and generation of electrical energy.

[0017] The beneficial effects of this invention are:

[0018] This invention has a simple and reliable structure, combining the advantages of electromagnetic power generation and piezoelectric power generation. It can capture and utilize wind energy under low wind speed conditions, and maximize the utilization of wind energy based on the vortex oscillation effect. This invention can be arrayed according to actual conditions, has good environmental adaptability, and can provide a better low wind speed wind energy capture device for areas with complex environments. Attached Figure Description

[0019] Figure 1 This is an overall schematic diagram of the energy harvesting system of the present invention;

[0020] Figure 2 This is a schematic diagram of the energy harvesting device of the present invention;

[0021] Figure 3 This is a schematic diagram of the piezoelectric layer in the energy harvesting unit of the present invention;

[0022] Figure 4 This is a schematic diagram of the magnetic sphere layer in the energy harvesting unit of the present invention;

[0023] Figure 5 This is a schematic diagram of the coil layer in the energy harvesting unit of the present invention;

[0024] In the diagram: 1. Fixing frame, 2. Flexible rope, 3. Energy harvesting device, 4. End cap, 5. Piezoelectric layer, 6. Magnetic ball layer, 7. Coil layer, 8. Single-layer shell, 51. L-shaped fixing piece, 52. Piezoelectric sheet, 53. Magnet, 61. Magnetic ball, 71. Coil. Detailed Implementation

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] like Figure 1 As shown, the low wind speed energy capture and power generation system of the present invention includes a fixed frame 1, a number of flexible ropes 2 and a number of energy capture devices 3. The top surface of the fixed frame 1 is installed at an external fixed point, and a number of flexible ropes 2 are evenly spaced along the circumference on the bottom surface of the fixed frame 1. The upper end of each flexible rope 2 is installed on the bottom surface of the fixed frame 1, and the lower end of each flexible rope 2 is connected to an energy capture device 3.

[0027] like Figure 2As shown, the energy harvesting device 3 includes an end cap 4 and several energy harvesting units, which are coaxially connected from top to bottom. The end cap 4 is installed on the top surface of the uppermost energy harvesting unit; the lower end of each flexible rope 2 is connected to the center of one of the lower end caps 4. There are 3-5 energy harvesting devices 3. The energy harvesting device 3 can maximize the capture of wind energy based on the vortex-induced oscillation effect, thereby improving the power generation of the energy harvesting power generation system. The energy harvesting unit includes a piezoelectric layer 5, a magnetic sphere layer 6, and a coil layer 7, which are coaxially connected from top to bottom. Each of the piezoelectric layer 5, magnetic sphere layer 6, and coil layer 7 includes a single-layer shell 8, which is cylindrical. The single-layer shells 8 are coaxially threaded together from top to bottom. The single-layer shell 8 is made of non-metallic material.

[0028] like Figure 3 As shown, the piezoelectric layer 5 also includes several L-shaped fasteners 51, several piezoelectric sheets 52, and several magnets 53. The piezoelectric sheets 52 are evenly spaced circumferentially on the inner wall of the single-layer shell 8 of the piezoelectric layer 5 and do not contact each other. One end of each piezoelectric sheet 52 is fixed to the inner wall of the single-layer shell 8 by an L-shaped fastener 51, and the other end of each piezoelectric sheet 52 faces the center of the single-layer shell 8. A magnet 53 is mounted on the upper side of the other end of each piezoelectric sheet 52. Each piezoelectric sheet 52 of the piezoelectric layer 5 is parallel to the bottom surface of the single-layer shell 8; the number of piezoelectric sheets 52, the number of L-shaped fasteners 51, and the number of magnets 53 in the piezoelectric layer 5 are equal. The piezoelectric sheets 52 are made of piezoelectric ceramic PZT material. The magnetic poles of two adjacent magnets 53 in the piezoelectric layer 5 are identical on the side closest to each other, and their magnetic repulsion facilitates oscillation.

[0029] like Figure 4 As shown, the magnetic ball layer 6 also includes a magnetic ball 61, which is placed inside the single-layer shell 8 of the magnetic ball layer 6 and is not fixed to the single-layer shell 8.

[0030] like Figure 5 As shown, the coil layer 7 also includes several coils 71, which are evenly spaced circumferentially on the inner bottom surface of the single-layer outer shell 8 of the coil layer 7. The coils 71 do not contact each other or the inner wall surface of the single-layer outer shell 8 of the coil layer 7. The axial direction of each coil 71 in the coil layer 7 is perpendicular to the bottom surface of the single-layer outer shell 8.

[0031] Under the influence of a natural breeze, each energy harvesting device 3 sways with the wind under the traction of the flexible rope 2, causing each energy harvesting unit to drive each magnetic ball 61 to roll within the single-layer shell 8 of the coil layer 7. This causes a change in the magnetic field around the magnetic ball 61, resulting in the self-oscillation of each magnet 53 within the piezoelectric layer 5, which in turn causes each piezoelectric sheet 52 to vibrate. The piezoelectric sheet 52 converts the mechanical energy of the vibration into electrical energy based on the piezoelectric effect. At the same time, the change in the magnetic field causes a change in the magnetic flux of each coil 71 within the coil layer 7, and the coil 71 converts wind energy into electrical energy based on electromagnetic induction.

[0032] Each piezoelectric element 52 is electrically connected to an external rectifier optimization circuit, and then electrically connected to an external energy storage device or external circuit through the rectifier optimization circuit; each coil 71 is electrically connected to an external energy storage device or external circuit to realize the transmission and generation of electrical energy.

[0033] The specific implementation process of this invention is as follows:

[0034] In practice, when a breeze blows, the energy harvesting device 3, suspended from the fixed frame 1 by the flexible rope 2, sways with the wind. The magnetic ball 61 inside the energy harvesting unit of the energy harvesting device 3 moves accordingly, causing a change in the surrounding magnetic field. The magnet 53 on the piezoelectric sheet 52 is affected by the magnetic field and moves, causing the piezoelectric sheet 52 to vibrate. The piezoelectric sheet 52 converts the mechanical energy of the vibration into electrical energy based on the piezoelectric effect. At the same time, the change in the magnetic field causes a change in the magnetic flux of the coil 71 inside the energy harvesting unit, generating electrical energy based on electromagnetic induction. The circular array arrangement of the energy harvesting device can capture more wind energy under the action of vortex turbine oscillation, realizing multi-directional wind energy harvesting.

[0035] This invention employs a hybrid power generation method combining piezoelectric energy capture based on the piezoelectric effect and electromagnetic energy capture using coils based on electromagnetic induction. Unlike traditional, complex large wind turbines, this invention features a simple and reliable structure, enabling the capture and utilization of micro-wind energy under low wind speed conditions, thus reducing the minimum wind speed required for wind energy generation. The invention utilizes a hybrid electromagnetic-piezoelectric energy capture method and maximizes wind energy utilization based on the vortex turbine oscillation effect. Furthermore, the energy capture device in this invention can be arrayed according to actual conditions, exhibiting excellent environmental adaptability and providing a superior wind energy capture device for regions with complex environments.

Claims

1. An electromagnetic-piezoelectric hybrid low wind speed energy harvesting and power generation system, characterized in that: The invention comprises a fixing frame (1), a plurality of flexible ropes (2) and a plurality of energy capture devices (3), wherein the top surface of the fixing frame (1) is mounted on an external fixing position, the bottom surface of the fixing frame (1) is provided with a plurality of flexible ropes (2) evenly spaced in a circumferential direction, the upper end of each flexible rope (2) is mounted on the bottom surface of the fixing frame (1), and the lower end of each flexible rope (2) is connected to an energy capture device (3); The energy capture device (3) comprises an end cover (4) and a plurality of energy capture units, wherein the energy capture units are coaxially connected and arranged in sequence from top to bottom, and the end cover (4) is installed on the top surface of the energy capture unit at the top layer; the lower end of each flexible rope (2) is connected to the center of an end cover (4) below; The energy capture unit comprises a piezoelectric layer (5), a magnetic sphere layer (6) and a coil layer (7) which are coaxially connected and arranged in sequence from top to bottom, the piezoelectric layer (5), the magnetic sphere layer (6) and the coil layer (7) each comprise a single-layer shell (8), the single-layer shell (8) is cylindrical, and each single-layer shell (8) is coaxially threadedly connected and arranged in sequence from top to bottom; The piezoelectric layer (5) further comprises a plurality of L-shaped fixing members (51), a plurality of piezoelectric sheets (52) and a plurality of magnets (53). The piezoelectric sheets (52) are evenly spaced and arranged along the circumferential direction on the inner wall surface of the single-layer shell (8) of the piezoelectric layer (5) without contacting each other. One end of each piezoelectric sheet (52) is fixed to the inner wall surface of the single-layer shell (8) of the piezoelectric layer (5) through the L-shaped fixing member (51). The other end of each piezoelectric sheet (52) faces the center of the single-layer shell (8) of the piezoelectric layer (5). A magnet (53) is installed on the upper side surface of the other end of each piezoelectric sheet (52). The magnetic ball layer (6) further comprises a magnetic ball (61), and the magnetic ball (61) is placed inside the single-layer shell (8) of the magnetic ball layer (6) and is not fixed to the single-layer shell (8); The coil layer (7) further comprises a plurality of coils (71), each coil (71) being evenly spaced and arranged along the circumferential direction on the inner bottom surface of the single-layer shell (8) of the coil layer (7), and each coil (71) is not in contact with each other and is not in contact with the inner wall surface of the single-layer shell (8) of the coil layer (7).

2. The electromagnetic-piezoelectric hybrid low wind speed energy harvesting power generation system according to claim 1, characterized in that: Each piezoelectric sheet (52) of the piezoelectric layer (5) is parallel to the bottom surface of the single-layer shell (8); the number of piezoelectric sheets (52) of the piezoelectric layer (5), the number of L-shaped fixing members (51) and the number of magnets (53) are equal.

3. The electromagnetic-piezoelectric hybrid low wind speed energy harvesting power generation system according to claim 1, characterized in that: The piezoelectric sheet (52) is made of piezoelectric ceramic PZT material.

4. The electromagnetic-piezoelectric hybrid low wind speed energy harvesting power generation system according to claim 1, characterized in that: The magnetic poles of two adjacent magnets (53) in the piezoelectric layer (5) on the sides close to each other are the same.

5. The electromagnetic-piezoelectric hybrid low wind speed energy harvesting power generation system according to claim 1, characterized in that: The axial direction of each coil (71) of the coil layer (7) is perpendicular to the bottom surface of the single-layer shell (8).

6. The electromagnetic-piezoelectric hybrid low wind speed energy harvesting power generation system according to claim 1, characterized in that: In the energy capture and power generation system, under the action of natural breeze, each energy capture device (3) swings with the wind under the traction of the flexible rope (2), driving each energy capture unit to drive each magnetic ball (61) to roll in the single-layer shell (8) of the coil layer (7), so that the magnetic field around the magnetic ball (61) changes, causing each magnet (53) in the piezoelectric layer (5) to generate self-vibration, driving each piezoelectric sheet (52) to vibrate, and the piezoelectric sheet (52) converts the mechanical energy of the vibration into electrical energy based on the piezoelectric effect; at the same time, the change in the magnetic field causes the magnetic flux of each coil (71) in the coil layer (7) to change, and the coil (71) converts wind energy into electrical energy based on electromagnetic induction; each piezoelectric sheet (52) is electrically connected to an external rectification optimization circuit, and then electrically connected to an external energy storage device or an external circuit through the rectification optimization circuit; each coil (71) is electrically connected to an external energy storage device or an external circuit to achieve transmission and power generation of electrical energy.

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