A GIS low-potential space electric field-magnetic field energy harvesting device

Abstract

This invention discloses a low-potential space electric-magnetic field energy harvesting device for GIS, comprising: a space magnetic field energy harvesting module and a space electric field energy harvesting module, which are electrically connected. The space magnetic field energy harvesting module includes a magnetoelectric conversion group for harvesting the space magnetic field energy surrounding the GIS and converting it into an induced voltage. The space electric field energy harvesting module is used to harvest the induced voltage surrounding the GIS. The space electric field energy harvesting module includes a piezoelectric transformer, which can both boost the harvested induced voltage and boost the induced voltage generated by the connected space magnetic field energy harvesting module. This invention possesses both space magnetic field and space electric field energy harvesting capabilities, enabling higher energy harvesting power. The space electric field energy harvesting module also has a boosting capability, improving the overall energy harvesting efficiency.

Description

Technical Field

[0001] This invention relates to the field of environmental energy harvesting for power equipment, specifically to a low-potential spatial electric and magnetic field energy harvesting device for GIS (Gas Insulated Switchgear). Background Technology

[0002] Smart sensing elements are installed at key equipment in smart grids and monitor critical parameters of each device's operation, enabling the smart grid to respond promptly to constantly changing environments. This is particularly beneficial for large-scale main equipment such as GIS systems, where wireless smart sensors can effectively reduce construction and electrical safety issues associated with cabling. However, power supply remains a significant bottleneck restricting its development. Currently, the vast majority of wireless sensors still rely on battery power, which limits their applications. Although some low-power wireless sensor networks can operate for several months, harvesting energy from the environment is an effective way to extend the lifespan of sensor nodes. This has become a practical yet urgent research area requiring solutions to numerous key technical problems.

[0003] The GIS (Gas Insulator) is surrounded by a strong induced magnetic field and voltage, from which energy can be extracted. However, GIS is a high-voltage device, while the monitoring equipment is a low-voltage device. Extracting energy from a high potential, although yielding a large amount of energy, presents challenges such as interference with the monitoring equipment, high-low voltage isolation, and grounding safety issues. Extracting energy from a low potential offers higher safety and less interference to the equipment, but the total amount of energy that can be extracted is lower, necessitating improvements in energy extraction efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a GIS low-potential space electric-magnetic field energy harvesting device to solve the problem of low energy harvesting in GIS low-potential technology.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A GIS low-potential space electric-magnetic field energy harvesting device includes: a space magnetic field energy harvesting module and a space electric field energy harvesting module, wherein the space magnetic field energy harvesting module is electrically connected to the space electric field energy harvesting module. The space magnetic field energy harvesting module is used to acquire the space magnetic field energy present around the GIS and convert it into an induced voltage, which is then input to the space electric field energy harvesting module. The space electric field energy harvesting module is connected to an input connection line, which is used to introduce the space induced voltage present around the GIS into the space electric field energy harvesting module. The space electric field energy harvesting module is used to boost the space induced voltage input through the input connection line and to boost the induced voltage generated by the space magnetic field energy harvesting module.

[0007] Furthermore, the space magnetic field energy harvesting module includes a magnetoelectric conversion group, which is provided in multiple groups. Each magnetoelectric conversion group consists of a negative electrode, a piezoelectric layer, a positive electrode, and a magnetostrictive layer stacked sequentially from bottom to top. The multiple magnetoelectric conversion groups are stacked and connected sequentially. The positive electrodes of the multiple magnetoelectric conversion groups are electrically connected to each other to form a positive terminal, and the negative electrodes are electrically connected to each other to form a negative terminal. The positive terminal and the negative terminal are respectively electrically connected to the space electric field energy harvesting module.

[0008] Furthermore, the positive electrode is composed of a first comb tooth grid structure and a first bus structure electrically connected to the first comb tooth grid structure, and the negative electrode is composed of a second comb tooth grid structure and a second bus structure electrically connected to the second comb tooth grid structure, with the comb teeth of the two comb tooth grid structures being alternately arranged.

[0009] Furthermore, the first comb-tooth gate structure, the second comb-tooth gate structure, the first bus structure, and the second bus structure are fabricated on the piezoelectric layer using photolithography.

[0010] Furthermore, the piezoelectric layer is made of relaxor ferroelectric single crystal, preferably lead zinc niobate polarized in the 001 direction or lead magnesium titanate magnesium niobate polarized in the 001 direction; the positive electrode and the negative electrode are both made of silver or gold.

[0011] Furthermore, the spatial electric field energy harvesting module includes a piezoelectric transformer, two input electrodes, an output electrode, and an energy harvesting capacitor. The length of the input electrodes is shorter than the length of the piezoelectric transformer. The two input electrodes are located on both sides of the piezoelectric transformer, and their length directions are parallel to the length direction of the piezoelectric transformer. One end of the two input electrodes is aligned with one end of the piezoelectric transformer. The piezoelectric transformer is connected to the output electrode, which is located at the end of the piezoelectric transformer away from the input electrodes. The positive and negative terminals are electrically connected to the two input electrodes, respectively. The output electrode is electrically connected to one end of the energy harvesting capacitor, and the other end of the energy harvesting capacitor is connected to the negative terminal of the output load. The two input electrodes are each connected to an input connection line.

[0012] Furthermore, the length of the input electrode is no more than two-thirds of the length of the piezoelectric transformer block and no less than one-third of the length of the piezoelectric transformer block; the length of the portion of the piezoelectric transformer block not covered by the input electrode is greater than or equal to four times the thickness of the piezoelectric transformer block, preferably four times, six times or eight times.

[0013] Furthermore, the input electrode and output electrode are both made of silver, the piezoelectric transformer is made of PZT piezoelectric ceramic, and the energy harvesting capacitor has a withstand voltage greater than 400V.

[0014] Furthermore, the space magnetic field energy harvesting module also includes a magnetic mass block and a cantilever beam bridge disposed on the magnetic mass block. The magnetoelectric conversion group is disposed on the cantilever beam bridge, and the cantilever beam bridge is mechanically connected to the piezoelectric transformer block. The material of the cantilever beam bridge is PZT piezoelectric ceramic.

[0015] Furthermore, the magnetostrictive layer and the positive or negative electrode are bonded together with epoxy resin.

[0016] Furthermore, the connection between the input electrode and the piezoelectric transformer, and between the output electrode and the piezoelectric transformer, are both achieved through slurry infiltration.

[0017] Furthermore, the magnetoelectric conversion group and the cantilever bridge, as well as the magnetic mass block and the cantilever bridge, are bonded together with epoxy resin, and the cantilever bridge and the piezoelectric transformer are mechanically connected by glass slurry sintering.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. The present invention provides a GIS low-potential space electric field-magnetic field energy harvesting device, which has both a space magnetic field energy harvesting module and a space electric field energy harvesting module. It can simultaneously harvest two types of environmental energy through the energy harvesting capacitor, thereby increasing the total amount of energy harvested.

[0020] 2. The space electric field energy harvesting module of the present invention is composed of a piezoelectric transformer block, which can boost the induced voltage and boost the voltage of the connected space magnetic field energy harvesting module, so that the voltage can charge the energy harvesting capacitor more quickly and improve the efficiency of energy harvesting.

[0021] 3. The present invention cascades multiple magnetoelectric conversion groups in the space magnetic field energy harvesting module, thereby increasing the total amount of magnetic field energy harvested. By constructing an electrode structure with a comb-like structure, the deformation of the piezoelectric layer under the same degree of magnetostriction is increased, thereby improving the efficiency of energy harvesting. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the GIS low-potential space electric field-magnetic field energy harvesting device of the present invention;

[0023] Figure 2 This is a schematic diagram of the space magnetic field energy harvesting module of the present invention;

[0024] Figure 3 This is a schematic diagram of the positive and negative electrodes in the magnetoelectric conversion assembly of the present invention;

[0025] Figure 4 This is a schematic diagram of the space electric field energy harvesting module of the present invention.

[0026] In the diagram: 1. Space magnetic field energy harvesting module; 2. Space electric field energy harvesting module; 3. Inter-module connection line; 11. Piezoelectric layer; 12. Positive electrode; 13. Negative electrode; 14. Magnetostrictive layer; 15. Cantilever beam bridge; 16. Magnetic mass block; 17. Magnetoelectric conversion group; 121. First comb-tooth grid structure; 122. First bus structure; 131. Second comb-tooth grid structure; 132. Second bus structure; 21. Piezoelectric transformer block; 22. Input electrode; 23. Output electrode; 24. Input connection line; 25. Energy harvesting capacitor; 26. Output connection line; 27. Output load negative terminal connection. Detailed Implementation

[0027] The present invention will be further described below with reference to specific embodiments. These embodiments are only used to more clearly illustrate the technical solutions of the present invention and should not be construed as limiting the scope of protection of the present invention.

[0028] like Figure 1 As shown, a GIS low-potential space electric field-magnetic field energy harvesting device includes: a space magnetic field energy harvesting module 1 and a space electric field energy harvesting module 2, which are electrically connected by an inter-module connection line 3.

[0029] The space magnetic field energy harvesting module 1 is used to acquire the space magnetic field energy existing around the GIS and convert the acquired space magnetic field energy into electric field energy.

[0030] like Figure 2 As shown, the space magnetic field energy harvesting module 1 includes two or more sets of magnetoelectric conversion groups 17 that are connected in sequence.

[0031] Each magnetoelectric conversion group 17 consists of a negative electrode 13, a piezoelectric layer 11, a positive electrode 12, and a magnetostrictive layer 14 stacked sequentially from bottom to top.

[0032] The magnetostrictive layer 14 is mechanically connected to the positive electrode 12 or the negative electrode 13 by bonding with epoxy resin.

[0033] Multiple sets of magnetoelectric conversion units 17 are mechanically connected to each other by epoxy resin bonding.

[0034] The piezoelectric layer 11 is made of a relaxor ferroelectric single crystal, preferably lead zinc niobate polarized in the 001 direction or lead magnesium titanate polarized in the 001 direction.

[0035] Both the positive electrode 12 and the negative electrode 13 are made of silver or gold.

[0036] By cascading multiple magnetoelectric conversion groups into a space magnetic field energy harvesting module, the total amount of magnetic field energy harvested can be increased.

[0037] To further improve the efficiency of energy harvesting, the positive electrode 12 and the negative electrode 13 are constructed as an electrode structure with a comb-like structure to increase the deformation of the piezoelectric layer 11 under the same degree of magnetostriction.

[0038] like Figure 3 As shown, both the positive electrode 12 and the negative electrode 13 are composed of a comb-tooth grid structure and a bus structure.

[0039] More specifically, the positive electrode 12 is composed of a first comb tooth grid structure 121 and a first bus structure 122 electrically connected to the first comb tooth grid structure 121, and the negative electrode 13 is composed of a second comb tooth grid structure 131 and a second bus structure 132 electrically connected to the second comb tooth grid structure 131, with the comb teeth of the two comb tooth grid structures being alternately arranged.

[0040] The first comb-tooth gate structure 121, the second comb-tooth gate structure 131, the first bus structure 122, and the second bus structure 132 are fabricated on the piezoelectric layer 11 by photolithography.

[0041] The positive electrode 12 and the negative electrode 13 adopt a comb-tooth grid structure. When the magnetostrictive layer 14 deforms under the action of an alternating magnetic field, compared with the general electrode structure that is covered with piezoelectric layer 11, the comb-tooth grid structure allows the piezoelectric layer 11 to generate more forced deformation. At the same time, stress concentration occurs at the edge of each grid of the comb-tooth grid structure, further increasing the deformation and thus increasing the total amount of electric field generated.

[0042] like Figure 1 , 2 As shown, the space magnetic field energy harvesting module 1 also includes a cantilever beam bridge 15 and a magnetic mass block 16.

[0043] The cantilever bridge 15 is mounted on the magnetic mass block 16, and the magnetoelectric conversion group 17 is mounted on the cantilever bridge 15.

[0044] The magnetic mass block 16 can provide a magnetic bending moment that varies with the alternating magnetic field to promote the deformation of the magnetostrictive layer.

[0045] Among them, the magnetoelectric conversion group 17 and the cantilever bridge 15, and the magnetic mass block 16 and the cantilever bridge 15 are all mechanically connected, and the connection method is to bond them with epoxy resin.

[0046] The cantilever bridge 15 is used to connect the space electric field energy harvesting module 2, and the material of the cantilever bridge 15 is PZT piezoelectric ceramic. In addition to its supporting function, the cantilever beam 15 can also be used to drive the deformation of the magnetoelectric material.

[0047] The spatial electric field energy harvesting module 2 is used to acquire the spatial electric field energy existing around the GIS, i.e., spatial induced voltage, and also has the ability to boost voltage.

[0048] like Figure 4 As shown, the space electric field energy harvesting module 2 includes a piezoelectric transformer 21, two input electrodes 22, an output electrode 23, an input connection line 24, and an energy harvesting capacitor 25.

[0049] The length of the input electrode 22 is less than the length of the piezoelectric transformer 21. The two input electrodes 22 are located on both sides of the piezoelectric transformer 21, and their length directions are parallel to the length direction of the piezoelectric transformer 21. One end of each input electrode 22 is aligned with one end of the piezoelectric transformer 21. The piezoelectric transformer 21 is connected to the output electrode 23, which is located at the end of the piezoelectric transformer 21 furthest from the input electrodes 22. The output electrode 23 is electrically connected to one end of the power harvesting capacitor 25 via the output connection line 26. The other end of the power harvesting capacitor 25 is electrically connected to the negative terminal of the output load 27. The power harvesting capacitor 25 is used to power loads such as wireless sensors.

[0050] The input electrode 22 and the piezoelectric transformer 21, as well as the piezoelectric transformer 21 and the output electrode 23, are all mechanically connected, and the connection method is slurry burning and seepage.

[0051] like Figure 1 As shown, the positive electrodes 12 of each group of magnetoelectric conversion groups 17 are electrically connected to each other and to one input electrode 22, and the negative electrodes 13 of each group of magnetoelectric conversion groups 17 are electrically connected to each other and to another input electrode 22, so as to boost the voltage generated by the connected space magnetic field energy harvesting module 1 through the space electric field energy harvesting module 2, thereby improving the efficiency of space magnetic field energy harvesting.

[0052] In a specific embodiment, the length of the input electrode 22 is no more than two-thirds of the length of the piezoelectric transformer 21, and no less than one-third of the length of the piezoelectric transformer 21. The portion of the piezoelectric transformer 21 not covered by the input electrode 22 (e.g., Figure 4 The length (indicated by the vertical arrow in the middle) is greater than or equal to the thickness of the piezoelectric transformer 21 (e.g., Figure 4 The distance between the horizontal arrows is 4 times, preferably 4 times, 6 times, or 8 times.

[0053] Both the input electrode 22 and the output electrode 23 are made of silver.

[0054] The piezoelectric transformer 21 is made of PZT piezoelectric ceramic.

[0055] The voltage rating of the 25-volt energy extraction capacitor is greater than 400V.

[0056] like Figure 4As shown, the two input electrodes 22 are also connected to input connection lines 24 respectively. The input connection lines 24 are used to introduce the alternating signal generated by the spatial induced voltage around the GIS to the spatial electric field energy harvesting module 2 to realize the spatial electric field energy harvesting capability. At the same time, the piezoelectric transformer block of the spatial electric field energy harvesting module 2 can also boost the input spatial induced voltage, thereby improving the spatial electric field energy harvesting capability.

[0057] like Figure 1 As shown, the cantilever beam bridge 15 of the space magnetic field energy harvesting module 1 and the piezoelectric transformer block 21 of the space electric field energy harvesting module 2 are mechanically connected by glass slurry sintering.

[0058] In a further embodiment, the input electrode 22 is electrically connected to the input connection line 24 by welding; the output connection line 26 is electrically connected to the output electrode 23 by welding; and the two ends of the energy harvesting capacitor 25 are electrically connected to the output connection line 26 and the output load negative terminal connection 27 by welding, respectively.

[0059] The space electric field energy harvesting module 2 is composed of a piezoelectric transformer block, which can boost the space induced voltage input through the input connection line 24, and also boost the voltage generated by the connected space magnetic field energy harvesting module 1, so that the voltage can charge the energy harvesting capacitor more quickly, thereby improving the energy harvesting efficiency.

[0060] The voltage boost is achieved through the piezoelectric effect of the piezoelectric transformer 21. The alternating signal generated by the induced voltage of the space magnetic field energy harvesting module 1 or the space induced voltage around the GIS is applied to the piezoelectric transformer 21 through the input electrode 22 to generate the inverse piezoelectric effect, causing it to vibrate. The vibration wave couples to the part of the piezoelectric transformer 21 not covered by the input electrode 21, generating charge through the direct piezoelectric effect, realizing the secondary conversion of electromechanical energy from electrical energy to mechanical energy to electrical energy back to electrical energy of the piezoelectric body. The highest output voltage is obtained at the resonant frequency of the piezoelectric transformer 21 and output through the output electrode 23.

[0061] The voltage boost ratio is determined by the ratio of the length of the portion of the piezoelectric transformer 21 not covered by the input electrode 22 to the thickness of the piezoelectric transformer 21. When this ratio is 4 times, the boost ratio is approximately 3.6.

[0062] The GIS low-potential space electric field-magnetic field energy harvesting device proposed in this invention has the ability to harvest energy from both space magnetic field and space electric field. It can simultaneously harvest two types of environmental energy through the energy harvesting capacitor, thereby increasing the total amount of energy harvested.

[0063] The space electric field energy harvesting module of this invention can boost both the induced voltage and the voltage generated by the connected space magnetic field energy harvesting module, enabling the voltage to charge the energy harvesting capacitor more quickly, improving the efficiency of energy harvesting, and also enabling voltage adaptation for subsequent energy management.

[0064] This invention cascades multiple magnetoelectric conversion groups in a space magnetic field energy harvesting module, thereby increasing the total amount of magnetic field energy harvested. By constructing an electrode structure with a comb-like structure, the deformation of the piezoelectric layer under the same degree of magnetostriction is increased, thus improving the efficiency of energy harvesting.

[0065] The present invention has been disclosed above with reference to preferred embodiments, but it is not intended to limit the present invention. All technical solutions obtained by adopting equivalent substitutions or equivalent transformations fall within the protection scope of the present invention.

Claims

1. A GIS low-potential space electric-magnetic field energy harvesting device, characterized in that, include: A space magnetic field energy harvesting module (1) and a space electric field energy harvesting module (2) are electrically connected. The space magnetic field energy harvesting module (1) is used to acquire the space magnetic field energy present around the GIS and convert it into an induced voltage, which is then input to the space electric field energy harvesting module (2). The space electric field energy harvesting module (2) is connected to an input connection line (24), which is used to introduce the space induced voltage present around the GIS into the space electric field energy harvesting module (2). The space electric field energy harvesting module (2) is used to boost the space induced voltage input through the input connection line (24) and boost the induced voltage generated by the space magnetic field energy harvesting module (1). The space magnetic field energy harvesting module (1) includes a magnetoelectric conversion group (17), which is provided in multiple groups. Each magnetoelectric conversion group (17) is composed of a negative electrode (13), a piezoelectric layer (11), a positive electrode (12) and a magnetostrictive layer (14) stacked sequentially from bottom to top. Multiple magnetoelectric conversion groups (17) are stacked and connected sequentially. The positive electrodes (12) of multiple magnetoelectric conversion groups (17) are electrically connected to each other to form a positive terminal, and the negative electrodes (13) are electrically connected to each other to form a negative terminal. The positive terminal and the negative terminal are electrically connected to the space electric field energy harvesting module (2) respectively. The positive electrode (12) is composed of a first comb tooth grid structure (121) and a first bus structure (122) electrically connected to the first comb tooth grid structure (121). The negative electrode (12) is composed of a second comb tooth grid structure (131) and a second bus structure (132) electrically connected to the second comb tooth grid structure (131). The comb teeth of the second comb tooth grid structure (131) and the comb teeth of the first comb tooth grid structure (121) are alternately arranged.

2. The GIS low-potential spatial electric-magnetic field energy harvesting device according to claim 1, characterized in that, The first comb gate structure (121), the second comb gate structure (131), the first bus structure (122), and the second bus structure (132) are fabricated on the piezoelectric layer (11) by photolithography.

3. The GIS low-potential space electric-magnetic field energy harvesting device according to claim 1 or 2, characterized in that, The piezoelectric layer (11) is made of relaxor ferroelectric single crystal; the positive electrode (12) and the negative electrode (13) are both made of silver or gold.

4. The GIS low-potential space electric-magnetic field energy harvesting device according to claim 3, characterized in that, The material of the piezoelectric layer (11) is lead zinc niobate polarized in the 001 direction or lead magnesium titanate magnesium niobate polarized in the 001 direction.

5. The GIS low-potential space electric-magnetic field energy harvesting device according to claim 1, characterized in that, The space electric field energy harvesting module (2) includes a piezoelectric transformer (21), two input electrodes (22), an output electrode (23), and an energy harvesting capacitor (25). The length of the input electrodes (22) is less than the length of the piezoelectric transformer (21). The two input electrodes (22) are located on both sides of the piezoelectric transformer (21), and the length direction of the two input electrodes (22) is parallel to the length direction of the piezoelectric transformer (21). One end of the two input electrodes (22) is aligned with one end of the piezoelectric transformer (21). The piezoelectric transformer (21) is connected to the output electrode (23). The output electrode (23) is located on the piezoelectric transformer (21) at the end away from the input electrode (22). The positive and negative terminals are electrically connected to the two input electrodes (22) respectively. The output electrode (23) is electrically connected to one end of the energy harvesting capacitor (25). The other end of the energy harvesting capacitor (25) is connected to the negative terminal of the output load (27). The two input electrodes (22) are each connected to an input connection line (24).

6. The GIS low-potential space electric-magnetic field energy harvesting device according to claim 5, characterized in that, The length of the input electrode (22) is no more than two-thirds of the length of the piezoelectric transformer (21) and no less than one-third of the length of the piezoelectric transformer (21); the length of the part of the piezoelectric transformer (21) not covered by the input electrode (22) is greater than or equal to four times the thickness of the piezoelectric transformer (21).

7. The GIS low-potential spatial electric-magnetic field energy harvesting device according to claim 6, characterized in that, The length of the portion of the piezoelectric transformer (21) not covered by the input electrode (22) is 4, 6 or 8 times the thickness of the piezoelectric transformer (21).

8. The GIS low-potential space electric-magnetic field energy harvesting device according to any one of claims 5 to 7, characterized in that, The input electrode (22) and output electrode (23) are both made of silver, the piezoelectric transformer (21) is made of PZT piezoelectric ceramic, and the energy harvesting capacitor (25) has a withstand voltage greater than 400V.

9. The GIS low-potential space electric-magnetic field energy harvesting device according to any one of claims 5 to 7, characterized in that, The space magnetic field energy harvesting module (1) also includes a magnetic mass block (16) and a cantilever beam bridge (15) disposed on the magnetic mass block (16). The magnetoelectric conversion group (17) is disposed on the cantilever beam bridge (15). The cantilever beam bridge (15) is mechanically connected to the piezoelectric transformer block (21). The material of the cantilever beam bridge (15) is PZT piezoelectric ceramic.

10. The GIS low-potential spatial electric-magnetic field energy harvesting device according to claim 1 or 2, characterized in that, The magnetostrictive layer (14) and the positive electrode (12) or negative electrode (13) are bonded together with epoxy resin.

11. The GIS low-potential space electric-magnetic field energy harvesting device according to any one of claims 5 to 7, characterized in that, The connection between the input electrode (22) and the piezoelectric transformer (21), and between the output electrode (23) and the piezoelectric transformer (21), is through slurry burning and seepage.

12. The GIS low-potential spatial electric-magnetic field energy harvesting device according to claim 9, characterized in that, The magnetoelectric conversion group (17) and the cantilever bridge (15) are bonded together with epoxy resin, and the magnetic mass block (16) and the cantilever bridge (15) are mechanically connected by glass slurry sintering.

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