A photovoltaic paper-cut structure and a manufacturing method thereof

Abstract

The application discloses a photovoltaic paper-cut structure and a manufacturing method thereof. The photovoltaic paper-cut structure comprises a rotating bottom plate and a photovoltaic device arranged on the rotating bottom plate. The rotating bottom plate comprises a rotating part for bearing the photovoltaic device, and a first micro hinge part and a second micro hinge part connected with the side edges of the rotating part. The first micro hinge part and the second micro hinge part are symmetrically distributed on the two sides of the rotating part. The first micro hinge part and the second micro hinge part are used for synchronously controlling the rotation of the rotating part to change the orientation of the photovoltaic device. The rotating part, the first micro hinge part and the second micro hinge part are integrally formed. The photovoltaic paper-cut structure disclosed by the application simplifies the structure of the photovoltaic paper-cut structure, saves the installation and control steps, and saves the manufacturing and maintenance costs through the integrated photovoltaic device and the rotating bottom plate structure for light tracking.

Description

Technical Field

[0001] This invention relates to the field of solar energy technology, and in particular to a photovoltaic paper-cutting structure and its manufacturing method. Background Technology

[0002] Common methods of utilizing solar energy include photovoltaic (PV) systems, which generate electricity by exposing semiconductor materials to sunlight, thus converting light energy into electrical energy. In actual production and use, due to the Earth's rotation, the direction of sunlight shining on a fixed point on the ground is always changing. To improve the electrical efficiency of PV modules, people have devised a light-tracing structure that changes the orientation of the PV panels according to the angle of the sun, ensuring that the sun always shines perpendicularly on the PV panels, thereby achieving better power generation.

[0003] However, current photovoltaic modules are heavy in structure, and when connected to the light tracking structure, the overall structure is heavy, the rotation method is complex, and the manufacturing and maintenance costs are high.

[0004] Therefore, existing technologies still need to be improved and developed. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a photovoltaic paper-cutting structure and its manufacturing method, which aims to solve the problem that the existing photovoltaic modules have complex structures and rotation methods, resulting in high manufacturing and maintenance costs.

[0006] The technical solution of the present invention is as follows:

[0007] A photovoltaic paper-cutting structure includes a rotating base plate and a photovoltaic device disposed on the rotating base plate; wherein, the rotating base plate includes a rotating part for supporting the photovoltaic device, and a first micro-hinge part and a second micro-hinge part connected to the side of the rotating part, the first micro-hinge part and the second micro-hinge part being symmetrically distributed on both sides of the rotating part; the first micro-hinge part and the second micro-hinge part are used to synchronously control the rotation of the rotating part to change the orientation of the photovoltaic device; the rotating part, the first micro-hinge part and the second micro-hinge part are integrally formed.

[0008] The photovoltaic paper-cutting structure, wherein the first micro-hinge portion includes a first connecting section, a first pulling section, and a second pulling section. The first connecting section is connected to the rotating portion, and a long strip-shaped first central seam is formed on the first connecting section. The first central seam extends in a direction perpendicular to the side of the rotating portion, and a first hinge area and a second hinge area are formed on both sides of the first central seam, respectively. The first pulling section is connected to the first hinge area and is used to pull the first hinge area to twist in a direction away from the second hinge area. The second pulling section is connected to the second hinge area and is used to pull the second hinge area to twist in a direction away from the first hinge area. The direction of the area is twisted; the second micro-hinge part includes a second connecting section, a third pulling section and a fourth pulling section. The second connecting section is connected to the rotating part, and a long strip-shaped second central slit is formed on the second connecting section. The second central slit extends in a direction perpendicular to the side of the rotating part. A third hinge area and a fourth hinge area are formed on both sides of the second central slit, respectively. The third pulling section is connected to the third hinge area and is used to pull the third hinge area to twist in a direction away from the fourth hinge area. The fourth pulling section is connected to the fourth hinge area and is used to pull the fourth hinge area to twist in a direction away from the third hinge area.

[0009] In the photovoltaic paper-cutting structure, both ends of the first central seam are provided with a first circular hole; both ends of the second central seam are provided with a second circular hole.

[0010] The photovoltaic paper-cutting structure, wherein the dimensionless characteristic length of the photovoltaic paper-cutting structure is L, satisfies the formula:

[0011]

[0012] Wherein, l is the sum of the length of the first central seam and the diameter of the two first circular holes; χ is the width of any one of the first traction section, the second traction section, the first hinge area, and the second hinge area.

[0013] In the aforementioned photovoltaic paper-cutting structure, the applied stress on the first or second tensioning section is σ, satisfying the formula:

[0014]

[0015] Where, σ max denoted as , where is the maximum stress that the first or second traction segment can withstand; 'a' is the length of the minor semi-axis of the first circular hole after it transforms into an ellipse during the traction process; and 'R' is the radius of the first circular hole.

[0016] The photovoltaic paper-cutting structure, wherein the photovoltaic device includes a light absorption region, an anode region, and a cathode region, and the light absorption region is connected to both the anode region and the cathode region.

[0017] In the photovoltaic paper-cutting structure, there are multiple rotating parts, and the multiple rotating parts are connected in series between the first micro-hinge part and the second micro-hinge part.

[0018] In the photovoltaic paper-cutting structure, the rotating part is rectangular, circular, triangular, or star-shaped.

[0019] The photovoltaic paper-cutting structure includes multiple first micro-hinge portions and multiple second micro-hinge portions, with the first and second micro-hinge portions arranged alternately in parallel; multiple rotating portions are connected in series between adjacent first and second micro-hinge portions.

[0020] The photovoltaic paper-cutting structure, wherein the rotating base plate includes one or more of the following: a flexible polycarbonate base plate, a polyethylene terephthalate film base plate, and a polyimide film base plate.

[0021] This application also discloses a method for manufacturing a photovoltaic paper-cutting structure, used to manufacture any of the photovoltaic paper-cutting structures described above, wherein the method includes:

[0022] Provide a rotating base plate;

[0023] A first micro-hinge section, a second micro-hinge section, and a rotating section are cut out from the rotating base plate;

[0024] A photovoltaic device functional layer thin film is prepared on the rotating part.

[0025] Compared with the prior art, the embodiments of the present invention have the following advantages:

[0026] The photovoltaic paper-cutting structure disclosed in this invention only requires an integrated, interconnected rotating part, a first micro-hinge part, and a second micro-hinge part to be set on a rotating base plate during production. Photovoltaic devices are then fabricated on the rotating part. During use, the photovoltaic devices on the rotating part absorb and convert solar energy. When the sun rotates, the rotation of the rotating part is controlled by adjusting the first and second micro-hinge parts, ensuring that the photovoltaic devices remain perpendicular to the sunlight and maintain high solar energy conversion efficiency. In summary, unlike traditional photovoltaic paper-cutting structures that require separate photovoltaic devices and independent light-tracking structures connected by additional wires, the photovoltaic paper-cutting structure disclosed in this invention uses a simple rotating base plate to achieve light-tracking functionality. Combined with the photovoltaic devices on the rotating base plate, the simple structure of the photovoltaic paper-cutting structure helps save on manufacturing and maintenance costs. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram illustrating the photoelectric conversion process of the photovoltaic paper-cutting structure in this invention.

[0029] Figure 2 This is a partial structural diagram of the photovoltaic paper-cutting structure in this invention;

[0030] Figure 3 This is a schematic diagram of the photovoltaic paper-cutting structure from another angle in this invention;

[0031] Figure 4 for Figure 3 A magnified view of a section at point A in the middle;

[0032] Figure 5 This is a schematic diagram of the photovoltaic paper-cutting structure in this invention;

[0033] Figure 6 for Figure 5 A magnified view of a section at point B in the middle;

[0034] Figure 7 Stress cloud diagrams of three photovoltaic paper-cutting structures simulated by ABAQUS;

[0035] Figure 8 To test the relationship between strain and nominal stress under different L values;

[0036] Figure 9 To test the relationship between strain and steering angle under different L values;

[0037] Figure 10 These are schematic diagrams of the three types of rotating base plates in this invention;

[0038] Figure 11 Stress cloud diagrams for three other photovoltaic paper-cutting structures simulated by ABAQUS;

[0039] Figure 12 Here are schematic diagrams of the four types of rotating base plates in this invention;

[0040] Figure 13 This is a schematic diagram of another photovoltaic paper-cutting structure in this invention;

[0041] Figure 14This is a flowchart of the manufacturing method of the photovoltaic paper-cutting structure in this invention.

[0042] Among them, 100 is a rotating base plate; 110 is a rotating part; 120 is a first micro-hinge part; 121 is a first connecting section; 121a is a first hinge area; 121b is a second hinge area; 122 is a first pulling section; 123 is a second pulling section; 124 is a first central seam; 125 is a first circular hole; 130 is a second micro-hinge part; 131 is a second connecting section; 131a is a third hinge area; 131b is a fourth hinge area; 132 is a third pulling section; 133 is a fourth pulling section; 134 is a second central seam; 135 is a second circular hole; 200 is a photovoltaic device; 210 is a light absorption area; 220 is an anode area; and 230 is a cathode area. Detailed Implementation

[0043] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] In existing technologies, photovoltaic (PV) systems are common structures that convert solar energy into electrical or thermal energy. The energy generated by a PV system is related to the absorbed irradiance E. i Regarding this, when all other parameters remain constant, non-normally incident irradiance reduces the output power of a photovoltaic cell. According to Lambert's cosine law, the irradiance E absorbed by a photovoltaic device... i It is proportional to the cosine of the angle between the incident ray and the normal to the plane containing the device, as shown in the following formula (1):

[0045]

[0046] Where E represents the radiation intensity at normal incidence.

[0047] like Figure 1 As shown in Figure (a), on a planar photovoltaic device without a light tracing mechanism, when the light source is incident perpendicular to the plane of the planar photovoltaic device, the absorbed irradiance E is... i =E, at which point the photoelectric conversion efficiency of the planar photovoltaic device reaches its maximum value.

[0048] like Figure 1 As shown in Figure (b), the photoelectric conversion efficiency changes with the incident angle of the light source. It increases and then gradually decreases until it becomes 0.

[0049] Therefore, people have added light-tracing structures to photovoltaic systems to sense the position of the light source in real time. For example... Figure 1 As shown in Figure (c), after connecting the planar photovoltaic device to the light tracking structure, whenever the light tracking structure senses a change in the position of the light source, it controls the planar photovoltaic device to rotate by a certain angle θ to maintain the perpendicular incidence of light on the surface of the planar photovoltaic device, achieving the effect of maximizing irradiance. Ideally, the light tracking structure can keep the planar photovoltaic device always absolutely perpendicular to the incident light, such as... Figure 1 As shown in Figure (d), maintaining E during the change of the incident light source angle is achieved. i =E, the photoelectric conversion efficiency is always at its maximum.

[0050] However, existing methods for adjusting planar photovoltaic devices using light tracking structures mostly involve connecting the control structure with additional wires, and then using the mechanical transmission of the control structure to flip the planar photovoltaic device, thereby achieving the effect of changing the angle of the planar photovoltaic device. This process involves many steps, is inconvenient to control, and the entire photovoltaic system has a complex structure, resulting in high production and maintenance costs.

[0051] See Figure 2 In one embodiment of this invention application, a photovoltaic paper-cutting structure is disclosed, including a rotating base plate 100 and a photovoltaic device 200 disposed on the rotating base plate 100; wherein, the rotating base plate 100 includes a rotating part 110 for supporting the photovoltaic device 200, and a first micro-hinge part 120 and a second micro-hinge part 130 connected to the side of the rotating part 110, the first micro-hinge part 120 and the second micro-hinge part 130 being symmetrically distributed on both sides of the rotating part 110; the first micro-hinge part 120 and the second micro-hinge part 130 are used to synchronously control the rotation of the rotating part 110 to change the orientation of the photovoltaic device 200; the rotating part 110, the first micro-hinge part 120 and the second micro-hinge part 130 are integrally formed.

[0052] The photovoltaic paper-cutting structure disclosed in this embodiment only requires an integrated, interconnected rotating part 110, a first micro-hinge part 120, and a second micro-hinge part 130 to be set on the rotating base plate 100. Then, a photovoltaic device 200 is fabricated on the rotating part 110. During use, the photovoltaic device 200 on the rotating part 110 is used to absorb and convert solar energy. When the sun rotates, the rotation of the rotating part 110 is controlled by adjusting the first micro-hinge part 120 and the second micro-hinge part 130, so that the photovoltaic device 200 can remain perpendicular to the sunlight and maintain high solar energy conversion efficiency. In general, unlike the traditional photovoltaic paper-cutting structure that requires an independent photovoltaic device 200 and an independent light tracking structure, and then connects the two with additional wires to function, the photovoltaic paper-cutting structure disclosed in this embodiment uses a simple rotating base plate 100 to achieve the light tracking function. Combined with the photovoltaic device 200 on the rotating base plate 100, the photovoltaic paper-cutting structure with its simple component structure is conducive to saving the manufacturing and maintenance costs of photovoltaic paper-cutting structures.

[0053] Furthermore, in this embodiment, the first micro-hinge portion 120 and the second micro-hinge portion 130 are symmetrically arranged on both sides of the rotating portion 110, providing torque simultaneously. This allows the rotating portion 110 to rotate at a high speed during rotation, and the forces on both sides are balanced, resulting in more precise control of the rotation angle of the rotating portion 110. This, in turn, improves the accuracy of adjusting the rotation angle of the photovoltaic device 200. In addition, the increased number of stress points on the rotating portion 110 can alleviate the problem of local force concentration at the connection between the rotating portion 110 and the first micro-hinge portion 120 or the second micro-hinge portion 130, reducing the probability of cracks or breakage on the rotating base plate 100 and extending the service life of the photovoltaic paper-cutting structure.

[0054] Specifically, as one embodiment of this invention, the rotating base plate 100 is disclosed to include one or more of the following: a flexible polycarbonate base plate, a polyethylene terephthalate film base plate, and a polyimide film base plate. Firstly, the photovoltaic paper-cutting structure needs to be placed outdoors in a location exposed to sunlight to perform photoelectric conversion. The rotating base plate 100, made of materials such as flexible polycarbonate, polyethylene terephthalate film, and polyimide film, has a high melting point, can withstand low temperatures, has low water absorption, and exhibits good impact resistance, insulation, and aging resistance. It can also withstand inorganic substances and dilute acids, allowing for long-term outdoor use and extending the service life of the photovoltaic paper-cutting structure.

[0055] Secondly, in the actual manufacturing process, the rotating base plate 100 has an integrated structure. It can be cut into three parts using laser cutting: a rotating part 110, a first micro-hinge part 120, and a second micro-hinge part 130. The resulting rotating part 110, first micro-hinge part 120, and second micro-hinge part 130 are on the same plane. During use, the first micro-hinge part 120 and second micro-hinge part 130 need to pull the rotating part 110 to rotate. Therefore, the rotating part 110... The plane at the starting point forms an angle with the plane where the first micro-hinge part 120 and the second micro-hinge part 130 are located. Therefore, the connection between the first micro-hinge part 120 and the second micro-hinge part 130 and the rotating part 110 will be twisted. Flexible materials such as flexible polycarbonate, polyethylene terephthalate film, and polyimide film have good deformation properties and are not easy to break. Moreover, after the torsion is restored, the rebound effect is good, which allows the photovoltaic paper-cut structure to be twisted repeatedly and still maintain a precise rotation angle and posture, maintaining normal use. Of course, the rotating base plate disclosed in this embodiment can also be made of other flexible plate-shaped materials by laser cutting, which will not be described in detail here.

[0056] like Figure 2 As shown, in another embodiment of this invention, the first micro-hinge portion 120 includes a first connecting section 121, a first pulling section 122, and a second pulling section 123. The first connecting section 121 is connected to the rotating portion 110, and an elongated first central slit 124 is formed on the first connecting section 121. The first central slit 124 extends in a direction perpendicular to the side of the rotating portion 110, and a first hinge area 121a and a second hinge area 121b are formed on both sides of the first central slit 124, respectively. The first pulling section 122 is connected to the first hinge area 121a and is used to pull the first hinge area 121a to twist in a direction away from the second hinge area 121b. The second pulling section 123 is connected to the second hinge area 121b and is used to pull the second hinge area 121b to twist in a direction away from the first hinge area 121a.

[0057] In this embodiment, the first micro-hinge portion 120 is made by cutting the rotating base plate 100. In the initial state, the first micro-hinge portion 120 and the rotating portion 110 are on the same plane, and the first connecting segment 121... The rotating part 110 is connected, and the first pulling section 122 and the second pulling section 123 are located on both sides of the first connecting section 121, respectively. In use, the first pulling section 122 or the second pulling section 123 is first lifted from the initial plane, and then the first pulling section 122 or the second pulling section 123 is pulled to both ends, so that the first pulling section 122 and the second pulling section 123 separate from each other. During the movement, the first central seam 124 on the first connecting section 121 expands, and the first hinge area 121a and the second hinge area 121b undergo out-of-plane buckling deformation under uniaxial tension. The first hinge area 121a and the second hinge area 121b twist in opposite directions, thereby transmitting torsional force to the end of the first connecting section 121. Since the end of the first connecting section 121 is connected to the rotating part 110, the rotating part 110 can be rotated at the same time, thereby achieving the effect of changing the orientation of the photovoltaic device 200. As can be seen, in this embodiment, the rotating base plate 100 is used to rotate the rotating part 110 by the force of the plate material when it is twisted, without the need for other structures or assemblies to twist the rotating part 110. This simplifies the structure of the photovoltaic paper-cutting structure, simplifies the steps to achieve the rotation of the photovoltaic device 200, and saves manufacturing and maintenance costs.

[0058] Specifically, the first micro-hinge part 120 disclosed in this embodiment can achieve omnidirectional angle control from -90° to 90° under uniaxial tension, so that the photovoltaic device 200 set outdoors can always maintain the perpendicular incidence of sunlight on the photovoltaic device 200, and maintain the high photoelectric conversion efficiency of the photovoltaic paper-cut structure.

[0059] like Figure 2 , Figure 3 and Figure 4As shown, the second micro-hinge portion 130 has the same structural shape and size as the first micro-hinge portion 120. The second micro-hinge portion 130 includes a second connecting section 131, a third pulling section 132, and a fourth pulling section 133. The second connecting section 131 is connected to the rotating portion 110, and an elongated second central slit 134 is formed on the second connecting section 131. The second central slit 134 extends in a direction perpendicular to the side of the rotating portion 110, and a third hinge area 131a and a fourth hinge area 131b are formed on both sides of the second central slit 134, respectively. The third pulling section 132 is connected to the third hinge area 131a and is used to pull the third hinge area 131a to twist in a direction away from the fourth hinge area 131b. The fourth pulling section 133 is connected to the fourth hinge area 131b and is used to pull the fourth hinge area 131b to twist in a direction away from the third hinge area 131a. In this embodiment, the first connecting segment 121 is the same as the second connecting segment 131, the first pulling segment 122 is the same as the third pulling segment 132, and the second pulling segment 123 is the same as the fourth pulling segment 133. When it is necessary to twist the photovoltaic device 200, the first pulling segment 122 and the third pulling segment 132, or the second pulling segment 123 and the fourth pulling segment 133, are lifted at the same time; then the first pulling segment 122 and the third pulling segment 132, or the second pulling segment 123 and the fourth pulling segment 133, are pulled at the same time; that is, torque is provided from both sides of the rotating part 110 at the same time, so that the rotating part 110 is stably twisted, avoiding the situation of the rotating part 110 rotating on one side, preventing the surface of the rotating part 110 from twisting, maintaining the planar state of the photovoltaic device 200, which is conducive to efficient absorption of light energy.

[0060] Specifically, as another implementation of this embodiment, the first traction segment 122 is connected to the first hinge area 121a at its midpoint; the second traction segment 123 is connected to the second hinge area 121b at its midpoint. During the traction process, the end of the first traction segment 122 is connected to the first hinge area 121a. When a traction force is generated, the force on the first hinge area 121a is evenly transmitted from the middle to both ends, and the magnitude of the force is consistent, avoiding the problem of excessive force on one side of the first connecting segment 121 and preventing tearing of the first connecting segment 121. The second traction segment 123 is located in the second hinge area 121b for the same reason, to protect the first connecting segment 121, so that the force on both ends of the first connecting segment 121 is as equal as possible, the force distribution is uniform, and the problem of stress concentration is avoided.

[0061] Specifically, in another embodiment of this invention, the third tension segment 132 is connected to the middle position of the third hinge area 131a; the fourth tension segment 133 is connected to the middle position of the fourth hinge area 131b. Similar to the aforementioned positioning of the first tension segment 122 and the second tension segment 123, this arrangement is intended to protect the second connecting segment 131 and prevent stress concentration on the second connecting segment 131.

[0062] For example Figure 2 and Figure 4 As shown, in another embodiment of this invention, both ends of the first central seam 124 are provided with first circular holes 125; both ends of the second central seam 134 are provided with second circular holes 135. In actual operation, when the first pulling section 122 and the second pulling section 123 are pulled, the first connecting section 121 experiences a pair of opposing forces converging at both ends. That is, at both ends of the first central seam 124, the first connecting section 121 experiences a relatively large force, making it prone to tearing and breakage. By providing the first circular holes 125, the arc-shaped sidewalls of the holes evenly distribute the force, reducing stress concentration at both ends of the first central seam 124, thereby allowing it to withstand greater tensile force and improving the structural strength of the first connecting section 121 to accommodate the larger tensile force applied by the first micro-hinge section 120 and the second micro-hinge section 130 when the rotating part 110 rotates at a large angle. Similarly, providing the second circular holes 135 can increase the structural strength of the second connecting section 131 to accommodate the tensile force of the third and fourth micro-hinge sections.

[0063] Specifically, as another implementation of this embodiment, the dimensionless characteristic length of the photovoltaic paper-cutting structure is disclosed as L. In actual use, L of the photovoltaic paper-cutting structure affects its light tracing performance (maximum rotation angle) and stress distribution. During manufacturing, the turning characteristics of the photovoltaic paper-cutting structure can be determined by testing the magnitude of L, which satisfies the formula:

[0064]

[0065] Among them, such as Figure 6 As shown, l is the sum of the length of the first central seam 124 and the diameter of the two first circular holes 125; χ is the width of any one of the first pulling section 122, the second pulling section 123, the first hinge area 121a, and the second hinge area 121b.

[0066] In this embodiment, the stress characteristics of photovoltaic paper-cut structures corresponding to different dimensionless characteristic lengths L can be simulated using software. For example, ABAQUS software is used for simulation. In the analysis step, stress contour maps of different dimensionless characteristic lengths L at the same turning angle (θ = 30°) are selected for comparison. The simulation results are as follows: Figure 7 As shown, the stress is mainly concentrated in the end area of ​​the first connecting section 121, while the large plane where the rotating part 110 is located has almost no visible stress or deformation. This indicates that the photovoltaic paper-cutting structure disclosed in this embodiment achieves turning while ensuring the stability of the photovoltaic device 200, which can stably absorb light energy and perform photoelectric conversion.

[0067] in addition, Figure 7 The corresponding maximum stress values ​​are 14.75 MPa, 4.23 MPa and 2.39 MPa, respectively. The dimensionless characteristic lengths L corresponding to the three photovoltaic paper-cutting structures are 2, 5 and 10, respectively. This shows that under the same turning angle, the maximum stress on the photovoltaic paper-cutting structure gradually decreases as the dimensionless characteristic length L increases.

[0068] Specifically, in this embodiment, the relationship between strain and nominal stress at different L values ​​can also be measured using testing equipment (such as the Instron 5966 electronic universal testing machine). The test results are as follows: Figure 8 As shown, Figure 8 The vertical axes in Figures (a) and (b) are displayed using linear and logarithmic methods, respectively. Using uncut polycarbonate as the reference experimental group, it can be seen that the deformation of uncut polycarbonate goes through two stages: (1) Elastic stage: Under external force, it undergoes a brief elastic deformation stage with a strain of less than 5%; (2) Plastic stage: It reaches the yield limit at 53.9 MPa and begins to undergo plastic deformation, at which point the deformation is irreversible. It fractures after the maximum strain reaches 28%, with a maximum nominal stress of 58 MPa at fracture. For the photovoltaic paper-cut structure, its deformation is divided into three stages: (1) Elastic stage: when the strain is less than 5%, it is similar to the stress state of polycarbonate without cuts and undergoes elastic deformation; (2) Secondary elastic plateau regime: after the strain exceeds 5%, the first connecting segment 121 and the second connecting segment 131 buckle under the action of external force. Due to the mechanical bistable state itself, it generates recoverable out-of-plane deformation, and the strain continues to increase; (3) Plastic stage: the first connecting segment 121 and the second connecting segment 131 continue to deform until fracture by relying on their own plasticity. The maximum strain before fracture is defined as the maximum strain of the photovoltaic paper-cut structure; when the dimensionless characteristic length L is 2, 5 and 10, the corresponding maximum strains are 74%, 237% and 426%, respectively.

[0069] Furthermore, the relationship between strain and the rotation angle of the photovoltaic paper-cutting structure can be measured during the test, and the measurement results are as follows: Figure 9As shown, the maximum rotation angle θ gradually increases with the increase of L, from 40°, 55° to 75°. This proves that the dimensionless characteristic length L of the photovoltaic paper-cutting structure affects its light-tracking performance. In actual testing, by controlling the dimensionless characteristic length to L, the photovoltaic paper-cutting structure can rotate within the range of -90° to 90°, thereby increasing its performance. The larger range of rotation angles when absorbing sunlight outdoors can increase the time of direct sunlight, improve the photoelectric conversion time, and increase the efficiency.

[0070] In summary, the first central seam 124 and the second central seam 134 on the first connecting segment 121 and the second connecting segment 131 enable the first micro-hinge portion 120 and the second micro-hinge portion 130, which undergo almost no elastic deformation, to acquire the ability to undergo elastic deformation. Furthermore, as the dimensionless characteristic length L increases, the maximum strain of the photovoltaic paper-cutting structure gradually increases. Under the same strain, increasing the dimensionless characteristic length L decreases the nominal stress, indicating an improvement in tensile strength, consistent with the trend of the simulation calculations above. Therefore, the tensile strength of the photovoltaic paper-cutting structure can be adjusted by controlling the dimensionless characteristic length L, thereby further precisely controlling the rotation angle of the photovoltaic paper-cutting structure and reducing the probability of structural cracks during rotation.

[0071] Specifically, in the field of solar energy technology, the geometry fill factor (GFF) of a photovoltaic paper-cut structure is also one of the important indicators of its performance. GFF is defined as the ratio of the coverage area of ​​the photovoltaic device 200 to the total area of ​​the rotating area; a higher geometry fill factor indicates higher area utilization. In this embodiment, the geometric parameters of the photovoltaic paper-cut structure were studied through finite element simulation and experiments, as follows:

[0072] During manufacturing, if the width of the first pulling section 122 or the width χ of the second pulling section 123 is changed, in order to ensure that the dimensionless feature length L remains unchanged, it is necessary to proportionally enlarge the length value of the first central seam 124, the sum of the diameter values ​​l of the two first circular holes 125, and the radius R of the first circular holes 125; as shown in Figure 10. Figure 10 In Figure (a), l = 10 mm, χ = 2 mm, and R = 0.2 mm; Figure 10 In Figure (b), l = 15 mm, χ = 3 mm, and R = 0.3 mm; Figure 10 In Figure (c), l = 20 mm, χ = 4 mm, and R = 0.4 mm.

[0073] like Figure 11As shown, the stress cloud diagrams for the three cases were simulated using ABAQUS software. Comparing the stress state at a turning angle θ = 30°, the simulation results show that the maximum stresses in the three cases are almost the same, at 4.08 MPa, 4.01 MPa, and 4.08 MPa, respectively. The reason for the slight equality is the limitation of the calculation step size. For example, the next step after 4.01 MPa is 4.3 MPa instead of 4.08 MPa. In other words, L determines the stress characteristics of the photovoltaic paper-cut structure. Under the same L, the maximum stress value and tensile properties of the photovoltaic paper-cut structure are the same. In addition, when L is the same, increasing χ will reduce the geometric fill factor of the photovoltaic paper-cut structure and reduce the area ratio of the photovoltaic device 200 in the rotating part 110. Therefore, in practical applications, the choice of χ should be as small as possible.

[0074] Specifically, as another implementation of this embodiment, it is disclosed that the stress state of the photovoltaic paper-cutting structure under rotation can be quantitatively studied according to the Inglis formula. During rotation, it is affected by the tension of the first tension section 122 and the second tension section 123, and the shape of the first circular hole 125 becomes elliptical. The minor semi-axis of the elliptical notch is a, and the major semi-axis is b, both in meters. The external stress on the first tension section 122 or the second tension section 123 is σ, in Pa, which satisfies the formula:

[0075]

[0076] Where, σ max R is the maximum stress that the first tension section 122 or the second tension section 123 can withstand; R is the radius of the first circular hole 125. It can be seen that increasing R can reduce stress concentration.

[0077] Specifically, as another embodiment of this invention, the photovoltaic device 200 includes a light absorption region 210, an anode region 220, and a cathode region 230. The light absorption region 210 is connected to both the anode region 220 and the cathode region 230. In this embodiment, the photovoltaic device 200 performs photoelectric conversion through the light absorption region 210, and the resulting current is conducted outward through the cathode and anode. Specifically, the first micro-hinge portion 120 is electrically connected to the anode region 220; the second micro-hinge portion 130 is electrically connected to the cathode region 230. The first micro-hinge portion 120 and the second micro-hinge portion 130 are configured as conductive paths, respectively connected to the anode region 220 and the cathode region 230. This increases the current output, eliminating the need for additional connecting wires to conduct current in the photovoltaic paper-cutting structure, further simplifying the structure, facilitating use, and saving costs.

[0078] Specifically, as another embodiment of this invention, the light absorption region 210 is disposed in the center of the rotating part 110; the anode region 220 is located on the rotating part 110 facing the first micro-hinge part 120; and the cathode region 230 is located on the rotating part 110 facing the second micro-hinge part 130. In the photovoltaic paper-cutting structure disclosed in this embodiment, the rotating part 110 rotates during light tracking. After rotation, the rotating part 110 is not coplanar with the first micro-hinge part 120 and the second micro-hinge part 130, and a portion of the rotating part 110 will rotate below the first micro-hinge part 120 and the second micro-hinge part 130. By placing the light absorption region 210 on the rotating part 110, it can avoid being blocked by the first micro-hinge part 120 or the second micro-hinge part 130, thereby improving the efficiency of photoelectric conversion of the photovoltaic device 200. The cathode region 230 and the anode region 220 are respectively disposed on both sides of the light absorption region 210, which can form a safe current and quickly lead it out from the first micro-hinge part 120 and the second micro-hinge part 130, avoiding contact at the rotating part 110.

[0079] like Figure 5 As shown, in another embodiment of this invention, multiple rotating parts 110 are provided, and these multiple rotating parts 110 are connected in series between the first micro-hinge part 120 and the second micro-hinge part 130. In this embodiment, the first pulling segment 122, the second pulling segment 123, the third pulling segment 132, and the fourth pulling segment 133 can all be extended into strips, so that multiple rotating parts 110 can be arranged in the strip-shaped space formed between the parallel first micro-hinge parts 120 and the second micro-hinge parts 130, thereby increasing the number of photovoltaic devices 200 that can be arranged on the photovoltaic paper-cutting structure and increasing the photoelectric conversion capability of the photovoltaic paper-cutting structure.

[0080] like Figure 12 As shown, in another embodiment of this invention, the rotating part 110 is disclosed to be rectangular, circular, triangular, or star-shaped. In actual manufacturing, the shape of the rotating part 110 can be flexibly designed based on available space. For example, designing the rotating part 110 as a rectangle resembles an indoor louver structure and can be used for indoor photovoltaic applications. Moreover, the rectangular shape of the rotating part 110 has the highest geometric fill factor, which can increase the photoelectric conversion capability of the photovoltaic paper-cut structure. Additionally, designing the rotating part 110 as circular, triangular, or star-shaped can have a decorative effect. Of course, the rotating part 110 disclosed in this embodiment can also be made into other shapes according to the usage scenario and requirements.

[0081] like Figure 13As shown, in another embodiment of this invention, multiple first micro-hinge portions 120 and multiple second micro-hinge portions 130 are disclosed, with the first micro-hinge portions 120 and the second micro-hinge portions 130 arranged alternately in parallel; multiple rotating portions 110 are connected in series between adjacent first micro-hinge portions 120 and second micro-hinge portions 130. In this embodiment, by arranging multiple first micro-hinge portions 120 and multiple second micro-hinge portions 130 at intervals, multiple rotating portions 110 can be arrayed. Only one end needs to be stretched to achieve synchronous rotation of multiple units, allowing multiple rotating portions 110 to rotate synchronously and simultaneously discharge electrical energy. This increases the total area while maintaining the vertical space utilization, improving the utilization efficiency of the photovoltaic paper-cut structure.

[0082] like Figure 14 As shown, as another embodiment of this application, a method for manufacturing a photovoltaic paper-cut structure is disclosed, used to manufacture the photovoltaic paper-cut structure as described above, wherein the method includes:

[0083] S100, Provides a rotating base plate 100;

[0084] S200, Cut out a first micro-hinge portion 120, a second micro-hinge portion 130 and a rotating portion 110 on the rotating base plate 100;

[0085] S300: A photovoltaic device functional layer thin film is prepared on the rotating part 110.

[0086] This embodiment discloses a method for preparing a photovoltaic paper-cut structure using a "paper-cutting" approach, achieving integration of the photovoltaic device 200 and the rotating base plate 100. Specifically, firstly, a transparent anode PEDOT:PSS of the photovoltaic device 200 is spin-coated onto a flexible polycarbonate substrate. PH1000 and hole transport layer PEDOT:PSS4083 were used. Then, a 355nm laser was used to cut out the first micro-hinge part 120, the second micro-hinge part 130, and the rotating part 110 required for the photovoltaic paper-cut structure. Next, a four-electrode atomization printing process was used on this structure to print the functional layer of the photovoltaic device 200. D18:Y6 (mass ratio 1:1.6) was dissolved in chloroform at 2.2mg / ml, stirred, and heated for more than 2 hours. The functional layer of the photovoltaic device 200 was then prepared on an atomization printing device with a working distance of 25mm, a voltage of 4.7kV, and a moving distance of 0.22mm / s. Afterward, the layer was transferred to a 90mm sealed glass petri dish, annealed in 100µL of chloroform solvent for 5 minutes, and then transferred to a pneumatic atomization platform to print the electron transport layer PNDIT-F3N of the photovoltaic device 200. Finally, a 100nm thick silver layer was deposited as the top electrode (cathode).

[0087] In summary, this application discloses a photovoltaic paper-cutting structure, including a rotating base plate 100 and a photovoltaic device 200 disposed on the rotating base plate 100; wherein, the rotating base plate 100 includes a rotating part 110 for supporting the photovoltaic device 200, and a first micro-hinge part 120 and a second micro-hinge part 130 connected to the side of the rotating part 110, the first micro-hinge part 120 and the second micro-hinge part 130 being symmetrically distributed on both sides of the rotating part 110; the first micro-hinge part 120 and the second micro-hinge part 130 are used to synchronously control the rotation of the rotating part 110 to change the orientation of the photovoltaic device 200; the rotating part 110, the first micro-hinge part 120 and the second micro-hinge part 130 are integrally formed. The photovoltaic paper-cutting structure disclosed in this embodiment only requires an integrated, interconnected rotating part 110, a first micro-hinge part 120, and a second micro-hinge part 130 to be set on the rotating base plate 100. Then, a photovoltaic device 200 is fabricated on the rotating part 110. During use, the photovoltaic device 200 on the rotating part 110 is used to absorb and convert solar energy. When the sun rotates, the rotation of the rotating part 110 is controlled by adjusting the first micro-hinge part 120 and the second micro-hinge part 130, so that the photovoltaic device 200 can remain perpendicular to the sunlight and maintain high solar energy conversion efficiency. In general, unlike the traditional photovoltaic paper-cutting structure that requires an independent photovoltaic device 200 and an independent light tracking structure, and then connects the two with additional wires to function, the photovoltaic paper-cutting structure disclosed in this embodiment uses a simple rotating base plate 100 to achieve the light tracking function. Combined with the photovoltaic device 200 on the rotating base plate 100, the photovoltaic paper-cutting structure with its simple component structure is conducive to saving the manufacturing and maintenance costs of photovoltaic paper-cutting structures.

[0088] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0089] It should be noted that this invention uses a photovoltaic paper-cutting structure as an example to introduce the specific structure and working principle of the invention, but the application of this invention is not limited to the photovoltaic paper-cutting structure, and can also be applied to the production and use of other similar workpieces.

[0090] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

[0091] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A photovoltaic paper-cutting structure, comprising a rotating base plate and photovoltaic devices disposed on the rotating base plate; characterized in that, The rotating base plate includes a rotating part for supporting the photovoltaic device, and a first micro-hinge part and a second micro-hinge part connected to the side of the rotating part. The first micro-hinge part and the second micro-hinge part are symmetrically distributed on both sides of the rotating part. The first micro-hinge part and the second micro-hinge part are used to synchronously control the rotation of the rotating part to change the orientation of the photovoltaic device. The rotating part, the first micro-hinge part, and the second micro-hinge part are integrally formed. The first micro-hinge portion includes a first connecting section, a first pulling section, and a second pulling section. The first connecting section is connected to the rotating portion, and a long strip-shaped first central slit is formed on the first connecting section. The first central slit extends in a direction perpendicular to the side of the rotating portion, and a first hinge area and a second hinge area are formed on both sides of the first central slit, respectively. The first pulling section is connected to the first hinge area and is used to pull the first hinge area to twist in a direction away from the second hinge area. The second pulling section is connected to the second hinge area and is used to pull the second hinge area to twist in a direction away from the first hinge area. The second micro-hinge portion includes a second connecting section, a third pulling section, and a fourth pulling section. The second connecting section is connected to the rotating part, and a long strip-shaped second central slit is formed on the second connecting section. The second central slit extends in a direction perpendicular to the side of the rotating part, and a third hinge area and a fourth hinge area are formed on both sides of the second central slit, respectively. The third pulling section is connected to the third hinge area and is used to pull the third hinge area to twist in a direction away from the fourth hinge area. The fourth pulling section is connected to the fourth hinge area and is used to pull the fourth hinge area to twist in a direction away from the third hinge area.

2. The photovoltaic paper-cutting structure according to claim 1, characterized in that, Both ends of the first central seam are provided with a first circular hole; both ends of the second central seam are provided with a second circular hole.

3. The photovoltaic paper-cutting structure according to claim 2, characterized in that, The dimensionless characteristic length of the photovoltaic paper-cutting structure is: It satisfies the formula: in, It is the sum of the length of the first central seam and the diameter of the two first circular holes; The width value is any one of the first traction segment, the second traction segment, the first hinge area, and the second hinge area.

4. The photovoltaic paper-cutting structure according to claim 2, characterized in that, The applied stress on the first or second tensioning section is It satisfies the formula: in, The maximum stress that the first or second tensioning segment can withstand; The length of the minor semi-axis of the first circular hole after it transforms into an ellipse during the pulling process; Let be the radius of the first circular hole.

5. The photovoltaic paper-cutting structure according to claim 1, characterized in that, The photovoltaic device includes a light-absorbing region, an anode region, and a cathode region, with the light-absorbing region connected to both the anode region and the cathode region.

6. The photovoltaic paper-cutting structure according to claim 1, characterized in that, The rotating part is provided in multiple ways, and the multiple rotating parts are connected in series between the first micro-hinge part and the second micro-hinge part.

7. The photovoltaic paper-cutting structure according to claim 1, characterized in that, The rotating part can be rectangular, circular, triangular, or star-shaped.

8. The photovoltaic paper-cutting structure according to claim 1, characterized in that, The first micro-hinge portion is provided in multiple ways, and the second micro-hinge portion is provided in multiple ways. The first micro-hinge portion and the second micro-hinge portion are arranged alternately in parallel. Multiple rotating portions are connected in series between adjacent first micro-hinge portions and second micro-hinge portions.

9. The photovoltaic paper-cutting structure according to claim 1, characterized in that, The rotating base plate includes one or more of the following: flexible polycarbonate base plate, polyethylene terephthalate film base plate, and polyimide film base plate.

10. A method for manufacturing a photovoltaic paper-cutting structure, used to manufacture the photovoltaic paper-cutting structure as described in any one of claims 1 to 9, characterized in that, include: Provide a rotating base plate; A first micro-hinge section, a second micro-hinge section, and a rotating section are cut out from the rotating base plate; A photovoltaic cell functional layer thin film is prepared on the rotating part.

Images