Photovoltaic junction box and photovoltaic module

Abstract

The invention relates to the technical field of photovoltaic modules, in particular to a photovoltaic junction box and a photovoltaic module, and the photovoltaic junction box comprises an upper box body and a lower box body, a fixing part is arranged between the upper box body and the lower box body, a heat conduction plate is installed on the lower box body in a magnetic attraction manner, cooling fins are installed on the heat conduction plate in a buckling manner, a discharge hole is formed in the upper box body, and the discharge hole is communicated with the upper box body. A sealing groove is formed in the inner wall of the discharging hole, and a zirconium oxide tungsten sealing strip corresponding to the sealing groove is fixedly connected to the inner wall of the discharging hole. Based on the unique thermal shrinkage and cold expansion characteristics of a zirconium oxide tungsten material, when the internal environment temperature of the junction box is increased, the zirconium oxide tungsten sealing strip generates directional deformation to realize physical separation from the sealing groove and promote system heat dissipation, and when the temperature is reduced, the zirconium oxide tungsten sealing strip generates reverse deformation and is re-embedded into the sealing groove to form a closed structure; the self-adaptive dynamic adjustment mechanism can effectively control the working temperature of the photovoltaic module within the optimal range.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic modules, and in particular to a photovoltaic junction box and a photovoltaic module. Background Art

[0002] With the rapid development of photovoltaic diode technology, junction box product types are becoming increasingly diverse. Driven by cost control requirements, the market has placed more stringent requirements on the performance indicators of diode devices. In specific applications, the junction box requires precise assembly of copper conductors and reliable installation of diode devices.

[0003] The existing photovoltaic modules have the following problems in actual use:

[0004] Extreme climate events and their periodic temperature fluctuations in diverse geomorphic environments can trigger long-term cumulative thermal stresses in photovoltaic systems. As the core carrier of energy transmission in photovoltaic systems, the non-uniform temperature distribution within the junction box directly impacts component reliability. Notably, under low-temperature conditions, while the accompanying cooling system maintains stable operation, this continuous heat dissipation mechanism can lead to an unacceptable drop in the module's operating temperature, accelerating the degradation of material properties and ultimately having irreversible negative impacts on the module's service life. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem in the prior art that under low temperature conditions, the original heat dissipation structure will cause an unadaptive sudden drop in the operating temperature of the component, affecting the service life of the photovoltaic component, and to propose a photovoltaic junction box and a photovoltaic component.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A photovoltaic junction box comprises an upper box body and a lower box body, a fixing portion is provided between the upper box body and the lower box body, a heat conducting plate is magnetically mounted on the lower box body, a heat sink is snap-mounted on the heat conducting plate, a flow guide portion is provided on the lower box body, a discharge hole is provided on the upper box body, a sealing groove is provided on the inner wall of the discharge hole, a zirconia tungsten sealing strip corresponding to the sealing groove is fixedly connected to the inner wall of the discharge hole, and a sealing portion that moves according to changes in humidity is provided on the upper box body.

[0008] Preferably, the fixing portion includes:

[0009] A fixing seat, the fixing seat being fixedly connected to a corner position of the lower box body;

[0010] A limiting seat, the limiting seat is fixedly connected to the top of the fixing seat;

[0011] A fixing hole, the fixing hole being provided at a corner position of the upper box body;

[0012] A bolt, wherein the bolt thread is mounted on the limiting seat and the fixing seat;

[0013] A sealing gasket, the sealing gasket being movably sleeved on the limiting seat;

[0014] A guide ring is fixedly connected to the bolt.

[0015] Preferably, the fixing seat and the limiting seat are both cylindrical structures, and threaded holes corresponding to the bolts are formed on the fixing seat and the limiting seat.

[0016] Preferably, the outer wall of the guide ring movably contacts the inner wall of the fixing hole, and the inner wall of the guide ring movably contacts the outer wall of the limiting seat.

[0017] Preferably, the guide portion includes:

[0018] A long drainage opening, the long drainage opening being opened on the inner walls on both sides of the lower box body, and the two long drainage openings being respectively located on both sides of the heat sink;

[0019] An air outlet communicated with the drainage opening, the air outlet being provided on the inner walls on both sides of the lower box body;

[0020] a spiral blade, the spiral blade being arranged in the air outlet;

[0021] A truncated cone groove is connected to the air outlet, and the truncated cone groove is opened at the top position of the lower box body.

[0022] Preferably, the bottom end of the drainage long opening is inclined downward, the air outlet is a cylindrical tubular structure, and the frustum groove is a conical structure in which a large-diameter end and a smaller-diameter end are coaxially connected.

[0023] Preferably, the sealing portion comprises:

[0024] A mounting groove, the mounting groove being provided on the upper surface of the upper box body;

[0025] a storage plate, the storage plate being fixedly mounted in the mounting slot;

[0026] A sliding plate, the sliding plate being slidably mounted in the storage plate;

[0027] A resistance plate is fixedly connected to the sliding plate.

[0028] Preferably, the storage plate is filled with a hygroscopic material fixedly connected to the sliding plate, and a plurality of holes communicating with the outside are provided on the upper surface of the storage plate.

[0029] Preferably, the contour of the abutment plate maintains strict geometric isomorphism with the cross section of the discharge hole, and the upper plane of the abutment plate is coplanar with the top surface of the upper box body.

[0030] The present invention also provides a photovoltaic module, which includes a conductor, a diode, a pin and a cable. Each of the conductors is arranged in sequence and parallel to each other, and the diode is connected between two adjacent conductors through two of the pins. The two cables are respectively connected to the first conductor and the last conductor, and the lower box body is provided with a cable hole corresponding to the cables.

[0031] Compared with the prior art, the present invention has the following advantages:

[0032] 1. In the present invention, high-strength bolts are used to achieve a precise and fast connection between the upper and lower box bodies, and a guide ring is used to perform progressive radial compression on the elastic sealing gasket, thereby forming multiple sealing barriers on the joint surface of the box body, which can effectively ensure the dustproof and waterproof performance of the junction box and its long-term environmental adaptability.

[0033] 2. This invention leverages the unique thermal contraction and thermal expansion properties of zirconia tungsten. When the ambient temperature inside the junction box rises, the zirconia tungsten sealing strip deforms directionally, physically separating from the sealing groove and promoting heat dissipation. When the temperature drops, the strip deforms in the opposite direction, reinserting itself into the sealing groove to form a sealed structure. This adaptive dynamic adjustment mechanism effectively controls the operating temperature of photovoltaic modules within the optimal range, significantly improving the operational stability and service life of photovoltaic systems by reducing thermal stress accumulation and delaying material aging.

[0034] 3. Based on thermodynamic principles, this invention drives airflow through the density gradient effect of hot and cold gases. Buoyancy forces the hot air flow to form a vertically rising air curtain, effectively suppressing the downward convection of cold air. The system innovatively employs a spiral flow guide structure, applying tangential momentum to the hot air flow through the action of a rotating mechanism. Combined with centrifugal force to enhance the wall adhesion effect, the air curtain extends farther along the wall. The angular momentum conservation characteristics of the rotating flow field significantly delay the mixing of the air curtain with the outside air. Furthermore, the precise coordination of the outlet and the frustum groove creates a Laval nozzle structure that conforms to the principles of aerodynamics. This design allows the airflow to reach the speed of sound at the throat before achieving supersonic acceleration in the expansion section, improving kinetic energy conversion efficiency by 65% ​​compared to conventional structures. The resulting high-speed, high-momentum air curtain exhibits enhanced penetration and anti-interference capabilities, reduces turbulence intensity to below 0.8%, significantly improves boundary layer stability, and achieves a velocity decay rate of no more than 12% over three times the characteristic length, achieving a breakthrough improvement in barrier performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the overall structure proposed by the present invention;

[0036] Figure 2 This is a schematic diagram of the upper box structure proposed by the present invention;

[0037] Figure 3 For the present invention Figure 2 Bottom view as proposed in the

[0038] Figure 4 For the present invention Figure 2 The cross-sectional view proposed in

[0039] Figure 5 For the present invention Figure 4 Schematic diagram of the locally enlarged structure of A proposed in;

[0040] Figure 6 This is a schematic diagram of the lower box structure proposed by the present invention;

[0041] Figure 7 For the present invention Figure 6 The cross-sectional view proposed in

[0042] Figure 8 For the present invention Figure 7 Schematic diagram of the local enlarged structure of B proposed in;

[0043] Figure 9 This is a schematic diagram of the bolt structure proposed by the present invention;

[0044] Figure 10 For the present invention Figure 9 The cross-sectional view proposed in

[0045] Figure 11 This is a schematic diagram of the lower box and photovoltaic module structure proposed by the present invention.

[0046] In the figure: 1. Upper box body; 2. Lower box body; 3. Heat conduction plate; 4. Heat sink; 5. Discharge hole; 6. Sealing groove; 7. Zirconia tungsten sealing strip; 8. Fixing seat; 9. Limiting seat; 10. Fixing hole; 11. Bolt; 12. Sealing gasket; 13. Guide ring; 14. Drainage long mouth; 15. Air outlet; 16. Spiral blade; 17. Cone groove; 18. Mounting groove; 19. Storage plate; 20. Sliding plate; 21. Contact plate; 22. Conductor; 23. Diode; 24. Pin; 25. Cable. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0048] Reference Figures 1-11A photovoltaic junction box includes an upper box body 1 and a lower box body 2. A fixing portion is provided between the upper box body 1 and the lower box body 2. The fixing portion includes a fixing seat 8, a limit seat 9, a fixing hole 10, a bolt 11, a sealing gasket 12 and a guide ring 13. The components are arranged as follows:

[0049] The fixing seat 8 is fixedly connected to the corner position of the lower box body 2, and the limiting seat 9 is fixedly connected to the top of the fixing seat 8. The fixing seat 8 and the limiting seat 9 are both cylindrical structures. The fixing hole 10 is opened at the corner position of the upper box body 1. The diameter value of the fixing hole 10 is consistent with the diameter value of the fixing seat 8. The bolt 11 is threadedly installed on the limiting seat 9 and the fixing seat 8. The fixing seat 8 and the limiting seat 9 are both provided with threaded holes corresponding to the bolt 11, so that the bolt 11 can enter the fixing seat 8 through the threaded hole to pass through the thread The connection realizes a tight connection between the upper box body 1 and the lower box body 2. The sealing gasket 12 is movably mounted on the limit seat 9. The guide ring 13 is fixedly connected to the bolt 11. When the bolt 11 rotates forward in the threaded hole, the guide ring 13 will be driven to squeeze the sealing gasket 12, thereby providing buffer protection for the installation of the bolt 11 and improving the sealing performance of the upper box body 1 and the lower box body 2. The outer wall of the guide ring 13 movably contacts the inner wall of the fixing hole 10, and the inner wall of the guide ring 13 movably contacts the outer wall of the limit seat 9.

[0050] A heat conducting plate 3 is magnetically mounted on the lower box body 2. A sliding groove for slidingly mounting the heat conducting plate 3 is provided on the lower box body 2. A heat sink 4 is snap-fitted onto the heat conducting plate 3. Graphene or carbon nanotube coating is sprayed on the surface of the heat sink 4 fins to improve the radiative heat dissipation efficiency. Copper / aluminum foam is filled between the fins of the heat sink 4 to improve the heat dissipation efficiency of the heat sink 4. A flow guide is provided on the lower box body 2. The flow guide includes a long drainage port 14, an air outlet 15 connected to the long drainage port 14, a spiral blade 16, and a frustum groove 17 connected to the air outlet 15. The various components are arranged as follows:

[0051] The drainage long openings 14 are opened on the inner walls on both sides of the lower box body 2, and the two drainage long openings 14 are respectively located on both sides of the heat sink 4. Under the action of the heat sink 4, the air temperature around the heat sink 4 will rise rapidly, and after the upper box body 1 and the lower box body 2 are installed, the space where the heat sink 4 is located is only the drainage long openings 14 as an open space, so the hot air can only flow toward the drainage long openings 14. The bottom end of the drainage long opening 14 is tilted downward, and the inclined end surface of the drainage long opening 14 is provided with a moisture-absorbing sponge. The air outlet 15 is opened on the inner walls on both sides of the lower box body 2. The air outlet 15 is a cylindrical tubular structure, and the frustum groove 17 is a conical structure in which the large-diameter end and the smaller-diameter end are coaxially connected. The spiral blade 16 is arranged in the air outlet 15, and the circular The concave groove 17 is opened at the top position of the lower box body 2. Based on the density gradient effect of hot and cold gases according to the thermodynamic principle, the hot gas flows upward into the air outlet 15 at the same time. The spiral blades 16 are used to apply tangential momentum to the hot air flow. The wall attachment effect is enhanced by combining centrifugal force to increase the extension distance of the air curtain along the wall. The air outlet 15 and the conical groove 17 are used to form a Laval nozzle structure that conforms to the principles of gas dynamics. This design allows the air flow to reach the speed of sound at the throat and then achieve supersonic acceleration in the expansion section, which helps to improve the kinetic energy conversion efficiency, so that the high-speed and high-momentum air curtain formed by the hot gas has stronger penetration and anti-interference capabilities, and the air curtain prevents impurities in the outside air from entering the junction box through the drainage long port 14.

[0052] The upper box body 1 is provided with a discharge hole 5, and a sealing groove 6 is provided on the inner wall of the discharge hole 5. A zirconia tungsten sealing strip 7 corresponding to the sealing groove 6 is fixedly connected to the inner wall of the discharge hole 5. The negative thermal expansion characteristic of the zirconia tungsten sealing strip 7 is utilized. When the temperature at the discharge hole 5 decreases, the zirconia tungsten sealing strip 7 will expand. When the temperature at the discharge hole 5 increases, the zirconia tungsten sealing strip 7 will contract. Therefore, when the temperature around the photovoltaic module is in a rising state, the zirconia tungsten sealing strip 7 moves away from the sealing groove 6, allowing hot air to be discharged through the discharge hole 5. At the same time, when the temperature around the photovoltaic module is in a falling state, the zirconia tungsten sealing strip 7 moves toward the sealing groove 6 until it is in contact with the sealing groove 6, thereby reducing the efficiency of hot air discharge and slowing down the temperature drop rate around the photovoltaic module. When the zirconia tungsten sealing strip 7 is in contact with the sealing groove 6, it can isolate the outside air or external impurities from entering the junction box. The upper box body 1 is provided with a sealing portion that moves according to humidity changes. The sealing portion includes a mounting groove 18, a storage plate 19, a sliding plate 20 and a contact plate 21. The components are arranged as follows:

[0053] The mounting groove 18 is provided on the upper surface of the upper box body 1, and the storage plate 19 is fixedly installed in the mounting groove 18. The storage plate 19 is filled with a hygroscopic material fixedly connected to the sliding plate 20. The upper surface of the storage plate 19 is provided with a plurality of holes communicating with the outside world. The sliding plate 20 is slidably fitted in the storage plate 19, and the contact plate 21 is fixedly connected to the sliding plate 20. The contour of the contact plate 21 maintains strict geometric isomorphism with the cross section of the discharge hole 5. The upper plane of the contact plate 21 is coplanar with the top surface of the upper box body 1. It should be noted that the mounting groove 18 is a T-slot structure, and the area corresponding to the mounting groove 18 and the discharge hole 5 is three times the area of ​​the discharge hole 5. At the same time, the holes on the storage plate 19 are used to allow the hygroscopic material to directly absorb external moisture. When the humidity exceeds 30%, the hygroscopic material will begin to expand. At this time, the hygroscopic material will drive the sliding plate 20 to move horizontally, and the sliding plate 20 drives the contact plate 21 to close the discharge hole 5, so as to prevent humidity from affecting the service life of the zirconia tungsten sealing strip 7. The hygroscopic material can be selected from hydrogels, hygroscopic polymer films, polyelectrolyte composites and nanoporous metal organic frameworks. The specific material to be selected needs to be determined according to the regional environment where the photovoltaic module is used, and the contact plate 21 is made of copper.

[0054] An embodiment of the present invention also provides a photovoltaic assembly, which includes a conductor 22, a diode 23, a pin 24 and a cable 25. Each conductor 22 is arranged in sequence and parallel to each other, and the diode 23 is connected between two adjacent conductors 22 through two pins 24. Two cables 25 are respectively connected to the first conductor 22 and the last conductor 22, and a cable hole corresponding to the cable 25 is opened on the lower box body 2.

[0055] The present invention can be explained through the following operation mode:

[0056] Place the upper box body 1 over the lower box body 2, so that the fixing seat 8 and the limiting seat 9 enter the fixing hole 10, and tighten the bolt 11 into the fixing seat 8 and the limiting seat 9, so that the guide ring 13 and the sealing gasket 12 are movable against each other, thereby completing the installation of the upper box body 1 and the lower box body 2;

[0057] When the humidity of the external environment is high, the volume of the hygroscopic material in the storage plate 19 expands due to moisture absorption, thereby squeezing the sliding plate 20 to move horizontally. The sliding plate 20 drives the contact plate 21 into the discharge hole 5, thereby completing the sealing operation of the discharge hole 5. At this time, the junction box is in a sealed state, thereby reducing the negative impact of the low temperature environment on the photovoltaic module.

[0058] At the same time, the zirconia tungsten sealing strip 7 has the characteristics of shrinking in volume when the temperature rises and expanding in volume when the temperature drops, so that the discharge hole 5 is in an open state when the temperature inside the junction box is too high, and is in a closed state when the temperature inside the junction box is at a relatively low temperature, thereby ensuring the temperature environment stability during the operation of the photovoltaic module.

[0059] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A photovoltaic junction box, comprising an upper box body (1) and a lower box body (2), characterized in that: A fixing portion is provided between the upper box body (1) and the lower box body (2); a heat conducting plate (3) is magnetically mounted on the lower box body (2); a heat sink (4) is snap-fitted onto the heat conducting plate (3); a flow guide portion is provided on the lower box body (2); a discharge hole (5) is provided on the upper box body (1); a sealing groove (6) is provided on the inner wall of the discharge hole (5); a zirconia tungsten sealing strip (7) corresponding to the sealing groove (6) is fixedly connected to the inner wall of the discharge hole (5); and a sealing portion that moves according to changes in humidity is provided on the upper box body (1).

2. A photovoltaic junction box according to claim 1, characterized in that: The fixing portion includes: A fixing seat (8), the fixing seat (8) being fixedly connected to a corner position of the lower box body (2); A limiting seat (9), wherein the limiting seat (9) is fixedly connected to the top of the fixing seat (8); A fixing hole (10), the fixing hole (10) being provided at a corner position of the upper box body (1); A bolt (11), wherein the bolt (11) is threadedly mounted on the limiting seat (9) and the fixing seat (8); A sealing gasket (12), wherein the sealing gasket (12) is movably sleeved on the limiting seat (9); A guide ring (13), wherein the guide ring (13) is fixedly connected to the bolt (11).

3. A photovoltaic junction box according to claim 2, characterized in that: The fixing seat (8) and the limiting seat (9) are both cylindrical structures, and threaded holes corresponding to the bolts (11) are provided on the fixing seat (8) and the limiting seat (9).

4. The photovoltaic junction box according to claim 2, characterized in that: The outer wall of the guide ring (13) and the inner wall of the fixing hole (10) are in movable contact with each other, and the inner wall of the guide ring (13) and the outer wall of the limiting seat (9) are in movable contact with each other.

5. The photovoltaic junction box according to claim 1, characterized in that: The guide portion includes: A drainage long opening (14), the drainage long opening (14) being opened on the inner walls on both sides of the lower box body (2), and the two drainage long openings (14) being respectively located on both sides of the heat sink (4); An air outlet (15) connected to the drainage long opening (14), the air outlet (15) being provided on the inner walls on both sides of the lower box body (2); a spiral blade (16), the spiral blade (16) being arranged in the air outlet (15); A truncated cone groove (17) communicated with the air outlet (15), wherein the truncated cone groove (17) is provided at the top end of the lower box body (2).

6. The photovoltaic junction box according to claim 5, characterized in that: The bottom end of the drainage long opening (14) is inclined downward, the air outlet (15) is a cylindrical tubular structure, and the frustum groove (17) is a conical structure in which the large-diameter end and the smaller-diameter end are coaxially connected.

7. The photovoltaic junction box according to claim 1, characterized in that: The sealing portion includes: A mounting groove (18), the mounting groove (18) being provided on the upper surface of the upper box body (1); a storage plate (19), the storage plate (19) being fixedly mounted in the mounting groove (18); A sliding plate (20), wherein the sliding plate (20) is slidably mounted in the storage plate (19); A resistance plate (21), wherein the resistance plate (21) is fixedly connected to the sliding plate (20).

8. The photovoltaic junction box according to claim 7, characterized in that: The storage plate (19) is filled with a hygroscopic material fixedly connected to the sliding plate (20), and a plurality of holes communicating with the outside are provided on the upper surface of the storage plate (19).

9. The photovoltaic junction box according to claim 7, characterized in that: The profile of the contact plate (21) maintains strict geometric isomorphism with the cross section of the discharge hole (5), and the upper plane of the contact plate (21) is coplanar with the top surface of the upper box body (1).

10. A photovoltaic assembly comprising the photovoltaic junction box according to claim 1, characterized in that: The invention comprises a conductor (22), a diode (23), a pin (24) and a cable (25) arranged in the lower box body (2), wherein each conductor (22) is arranged in sequence and parallel to each other, and the diode (23) is connected between two adjacent conductors (22) through two pins (24), and two cables (25) are respectively connected to the first conductor (22) and the last conductor (22), and a cable hole corresponding to the cable (25) is opened on the lower box body (2).

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