Shadow-proof solar photovoltaic module and forming process thereof

Abstract

The application relates to a shadow-proof solar photovoltaic module and a forming process thereof, and belongs to the technical field of photovoltaics, which comprises a photovoltaic frame, a back plate, a glass layer and two symmetrically arranged power supply mechanisms, the power supply mechanisms comprise first and second photovoltaic units connected in parallel, each photovoltaic unit is composed of a plurality of cell groups connected in series, the back plate is provided with an intermediate bus bar corresponding to the cell groups, the intermediate bus bar is provided with a diode arranged reversely, so that the first and second photovoltaic units form a same-frequency reverse circuit; the unique bus bar layout and the reverse arrangement of the diode enable the module to maintain stable power output when partially shadowed, and greatly reduce the influence of the shadow on the power generation efficiency; the application also relates to a forming process of the solar photovoltaic module, which adopts segmented lamination, controls temperature and pressure variation, ensures reliable fixation of the diode and the bus bar, and improves the structural stability and durability of the module.

Description

Technical Field

[0001] This invention relates to the field of solar photovoltaic modules, and in particular to a solar photovoltaic module with anti-shading properties and its molding process. Background Technology

[0002] Solar panels, also known as photovoltaic modules, are devices that directly convert sunlight into electrical energy using the photovoltaic effect of semiconductor materials. Their core power generation unit is the solar cell, primarily made of silicon, which can be categorized into high-efficiency monocrystalline silicon and lower-cost polycrystalline silicon. Panels are connected in series to form modules, which are widely used in centralized photovoltaic power plants, distributed rooftop systems, and spacecraft.

[0003] When existing solar panels are blocked by leaves or other debris, their output power is greatly affected, and hot spot effect occurs. Currently, when solar panels are blocked, the hot spot effect can be avoided by using diodes. However, the installation of diodes will reduce the voltage of the solar panel by more than one-third, which will affect the charging effect of the energy storage battery. In addition, the existing diodes are pre-encapsulated in the junction box, which has slow heat dissipation and will cause the local temperature of the solar panel to be too high, which will greatly affect the power generation of the solar panel and is very inconvenient. Summary of the Invention

[0004] The purpose of this invention is to provide a solar photovoltaic module that prevents shading. The area of ​​a single solar panel is reduced to half of its original size, and the existing photovoltaic module is divided into multiple units connected in parallel. Each unit has the same number of cells connected in series and the voltage is the same. Furthermore, a diode is installed to protect each cell group in each unit. Based on this design, the output voltage can remain unchanged even when some photovoltaic units are shaded, thus avoiding the problem of reduced charging power of the energy storage battery.

[0005] The technical solution to achieve the purpose of this invention is as follows: This invention has a photovoltaic frame, within which a backplate and a glass layer for light transmission are fixedly installed. A positive terminal box and a negative terminal box are provided on the backplate. Two symmetrically arranged power supply mechanisms are provided between the backplate and the glass layer. The positive and negative terminal boxes are located between the respective power supply mechanisms. Each power supply mechanism includes at least one photovoltaic unit group. Each photovoltaic unit group includes a first photovoltaic unit and a second photovoltaic unit arranged side-by-side along the long side of the photovoltaic frame, and a busbar group located between the first and second photovoltaic units. Each first and second photovoltaic unit includes multiple groups of solar cells arranged side-by-side and connected in series along the wide side of the photovoltaic frame. Each solar cell group consists of multiple solar cells connected in series via solder strips. The busbar group includes a first main busbar and a second main busbar fixed to the backplate. Solar cell groups on one side are electrically connected to the first main busbar via solder strips, and solar cell groups on the other side are electrically connected to the second main busbar via solder strips. The backplate also provides intermediate busbars corresponding to each solar cell group. Intermediate busbars are arranged parallel to the long side of the photovoltaic frame. Each intermediate busbar is positioned between its corresponding cell group and backsheet, and is insulated from the corresponding cell group. The intermediate busbars located on the back of the cell groups at the two side edges are electrically connected to the first main busbar and the second main busbar, respectively. The first main busbar is electrically connected to the positive terminal box through its corresponding intermediate busbar, and the second main busbar is electrically connected to the negative terminal box through its corresponding intermediate busbar. Each intermediate busbar passing under each cell group in the first photovoltaic unit is equipped with a diode. Adjacent intermediate busbars in the first photovoltaic unit... The diodes are reverse-biased. In each intermediate busbar passing under the cell group in the second photovoltaic unit, except for the intermediate busbars on both sides that connect to the first and second main busbars, diodes are also provided on the remaining intermediate busbars. The diodes on adjacent cell groups are reverse-biased. The corresponding diodes in the first and second photovoltaic units are reverse-biased. The first and second photovoltaic units are connected in parallel through the connection of one side of the intermediate busbar to the first main busbar and the connection of the other side of the intermediate busbar to the second main busbar, forming a same-frequency reverse circuit.

[0006] Furthermore, both the first and second photovoltaic units mentioned above include a first cell group, a second cell group, a third cell group, and a fourth cell group arranged side-by-side and connected in series along the wide side of the photovoltaic frame. The busbar group also includes a third busbar disposed between the first and second main busbars. Sideband groups are also provided on both sides of the first and second photovoltaic units. These sideband groups include a first busbar spanning the first and second cell groups, and a second busbar spanning the third and fourth cell groups. The two ends of the first cell group are electrically connected to the first main bus and the first bus via solder ribbons, respectively. The two ends of the second cell group are electrically connected to the first bus and the third bus via solder ribbons, respectively. The two ends of the third cell group are electrically connected to the third bus and the second bus via solder ribbons, respectively. The two ends of the fourth cell group are electrically connected to the second bus and the second main bus via solder ribbons, respectively. The first cell group, the second cell group, the third cell group, and the fourth cell group are connected in series with the first main bus, the first bus, the third bus, the second bus, and the second main bus via solder ribbons.

[0007] Furthermore, the backplate is provided with a first intermediate busbar corresponding to the first cell group, a second intermediate busbar corresponding to the second cell group, a third intermediate busbar corresponding to the third cell group, and a fourth intermediate busbar corresponding to the fourth cell group. The first intermediate busbar is electrically connected in sequence to the first busbar, the first main busbar, and the positive terminal box of the first photovoltaic unit. The second intermediate busbar is electrically connected in sequence to the first busbar, the third busbar, the first busbar of the second photovoltaic unit, and the positive terminal box of the first photovoltaic unit. The third intermediate busbar is electrically connected in sequence to the second busbar, the third busbar, the second busbar of the second photovoltaic unit, and the negative terminal box of the first photovoltaic unit. The fourth intermediate busbar is electrically connected in sequence to the second busbar, the third busbar, and the negative terminal box of the first photovoltaic unit.

[0008] Furthermore, both sides of the aforementioned positive and negative terminal boxes are provided with connecting busbars. The connecting busbar on one side of the positive terminal box is connected to the first intermediate busbar, the connecting busbar on the other side of the positive terminal box is connected to the second intermediate busbar, the connecting busbar on one side of the negative terminal box is connected to the third intermediate busbar, and the connecting busbar on the other side of the negative terminal box is connected to the fourth intermediate busbar.

[0009] Furthermore, each diode is evenly distributed on the intermediate busbar along the extension direction of the intermediate busbar and is fixedly connected to the intermediate busbar by welding.

[0010] Furthermore, the backplate is provided with mounting slots corresponding to each intermediate busbar. The backplate is covered with a first EVA film, which extends along the contour of the backplate. The intermediate busbars with multiple diodes are fixed in the mounting slots by the first EVA film.

[0011] Furthermore, an insulating strip is also provided in the aforementioned mounting groove, which is pressed against the intermediate busbar.

[0012] Furthermore, a wide EVA film is provided between the aforementioned battery cell assembly and the insulating strip, the width of which is greater than the width of the insulating strip. A POE film is provided between the battery cell assembly and the glass layer. The battery cell assembly is fixedly connected to the insulating strip through the wide EVA film, and the glass layer is fixedly connected to the battery cell assembly through the POE film.

[0013] The purpose of this invention is to provide a molding process for a solar photovoltaic module based on the above-mentioned anti-shading technology. The glass layer, the cell array, the intermediate busbars, and the diodes are formed by lamination. By segmented lamination, the gaps between the various materials can be eliminated, greatly reducing the impact of the diodes on the cells and preventing the photovoltaic cells from breaking. At the same time, it can also allow the encapsulant films to fully melt, increasing the cross-linking degree of the encapsulant films and the adhesion between the encapsulant films and the backsheet, thereby enhancing the service life of the solar panel.

[0014] The technical solution to achieve the objective of this invention is as follows: This invention includes the following steps:

[0015] P1. Solder the corresponding number of diodes onto each intermediate busbar;

[0016] P2. Connect the individual photovoltaic cells in the cell array in series to form a complete cell array.

[0017] P3. Lay POE film on the glass layer;

[0018] P4. Place the connected battery cell groups on the POE film in sequence, adjust the spacing between the battery cell groups, and fix them with tape.

[0019] P5. Place a wide EVA film, wider than the insulating strip, on each battery cell group;

[0020] P6. Place the intermediate busbars that are soldered to each diode on the insulating strip and fix them with tape;

[0021] P7. Lay the first EVA film on each battery cell group, insulating strip and intermediate busbar, and wrap the battery cell group, insulating strip and intermediate busbar between the first EVA film and the glass layer.

[0022] P8. Lay the backing plate on the first EVA film and embed the insulating strip and intermediate busbar into the mounting groove to form the part to be laminated.

[0023] P9. Place the part to be laminated into the laminator and form a laminate by segmented lamination;

[0024] P10. After lamination, the laminated component is removed from the laminator and cooled to form a complete solar panel.

[0025] Furthermore, the above-mentioned segmented lamination is divided into two stages. The temperature of the first stage of lamination is 110±3℃, and the temperature of the second stage of lamination is 140±3℃. The lamination pressure gradually increases from -80MPa to -35MPa.

[0026] The present invention has the following positive effects: (1) The present invention sets a positive terminal box and a negative terminal box on the back plate, and sets a power supply mechanism between the back plate and the glass layer, sets each power supply mechanism into multiple photovoltaic unit groups, and sets each photovoltaic unit group into a first photovoltaic unit and a second photovoltaic unit. The first photovoltaic unit and the second photovoltaic unit are connected in parallel through the connection of one side intermediate busbar to the first total busbar and the connection of the other side intermediate busbar to the second total busbar, and form a same frequency reverse circuit. By reducing the area of ​​the original single cell, the heat generated is reduced and the power loss is reduced. At the same time, multiple first photovoltaic units and second photovoltaic units are set in parallel, and each first photovoltaic unit and second unit is connected in series with a cell group. With the same number of photovoltaic cells in each cell group, and each cell group having a diode for protection, when any one or more photovoltaic units are shaded, the parallel-connected first and second photovoltaic units can ensure that the output voltage remains unchanged, and the charging efficiency of the energy storage battery will not be affected by the voltage drop. In addition, installing each diode on the corresponding intermediate busbar can greatly accelerate the heat dissipation efficiency of the diode, avoiding the hot spot effect and the problem of reduced power generation due to excessive local temperature, and also greatly reducing the power loss of the solar panel. As long as the voltage of one unit is greater than the voltage required for energy storage, the energy storage battery can be charged, improving the charging efficiency of the energy storage battery. The structure is ingenious, efficient and convenient.

[0027] (2) This invention sets up four battery cell groups, and the first, second, third and fourth battery cell groups are connected to the first and second busbars through the solder strips on the photovoltaic cells. By connecting with the first, second and third busbars, the first, second, third and fourth battery cell groups form a clean series circuit, which optimizes the internal current path, reduces long-distance layout, and reduces line loss. The diodes on the first and second photovoltaic units are reversed, which corresponds to the symmetrical and opposite current flow direction of the first and second photovoltaic units. This also ensures that the current between the first and second photovoltaic units will not be connected in series, and also ensures the independence of the voltage of the first and second photovoltaic units.

[0028] (3) The present invention sets up a first intermediate busbar, a second intermediate busbar, a third intermediate busbar and a fourth intermediate busbar, and connects the first intermediate busbar to the first main busbar and the fourth intermediate busbar to the idier main busbar, thereby realizing the parallel connection of the first photovoltaic unit and the second photovoltaic unit. The first intermediate busbar is not connected to the first busbar of the second photovoltaic unit and the fourth intermediate busbar is not connected to the second busbar of the second photovoltaic unit, thus avoiding short circuits during operation and effectively ensuring the stability and safety of the circuits of the first photovoltaic unit and the second photovoltaic unit. It is convenient and practical.

[0029] (4) By setting connecting busbars on both sides of the positive and negative terminal junction boxes and connecting them to the first intermediate busbar, the second intermediate busbar, the third intermediate busbar and the fourth intermediate busbar respectively, the present invention forms a dual-parallel lead-out structure, which not only reduces the current density at the junction box and reduces heat generation, but also improves the reliability of the component under high current conditions.

[0030] (5) By uniformly distributing the diodes along the extension direction of the middle busbar, the present invention avoids local accumulation of diodes. Compared with the traditional method of concentrating all diodes in the junction box, this distributed design greatly increases the heat dissipation area, allowing heat to be quickly dissipated through the back panel, effectively reducing the local operating temperature of the module, thereby improving the power generation and module life.

[0031] (6) The present invention achieves effective positioning and encapsulation of the diode by setting a mounting groove on the back plate and using the first EVA film to fix the intermediate busbar with the diode in the mounting groove. The first EVA film has good fluidity and adhesion after lamination, ensuring that the diode does not shift during long-term use and ensuring electrical insulation safety.

[0032] (7) By adding an insulating strip in the mounting groove and pressing it against the intermediate busbar after lamination, the present invention further enhances the electrical isolation effect between the intermediate busbar and the battery pack, effectively preventing the risk of leakage. At the same time, the physical pressing effect of the insulating strip enhances the positional stability of the intermediate busbar during the lamination process.

[0033] (8) This invention uses an EVA film with a width greater than that of the insulating strip to fix the battery cell pack to the insulating strip, and uses a POE film to encapsulate the glass layer and the battery cell pack. This achieves complementary advantages of materials, protects the fragile battery cells, and the POE film gives full play to its excellent anti-aging and insulation properties, thereby improving the weather resistance and safety of the module.

[0034] (9) This invention ensures the reliability of electrical connection by first pre-welding diodes on the intermediate busbar and then sequentially laying adhesive film, battery cells and backplate. The diodes are not pre-encapsulated, but encapsulated in the lamination process, which reduces the thickness of the diodes, reduces the defects of battery cell breakage, greatly improves the heat dissipation effect of the diodes, and avoids the problem of low charging efficiency caused by local overheating. At the same time, setting a wide EVA adhesive film and insulating strip between the battery cell group and the diode can prevent the battery cell group from being electrically connected to the intermediate busbar, so that the two are in an insulating state. The wide EVA adhesive film and insulating strip can also reduce the risk of cell breakage caused by lamination through buffering, and improve the yield of products.

[0035] (10) This invention uses a two-stage lamination method, setting the lamination temperature of the first stage to 110°C. At this temperature, the first EVA film, the wide-width EVA film, and the POE film melt slowly, exhibiting low fluidity. This slow melting allows them to fill the gaps between the materials, thereby reducing the impact on each photovoltaic cell and preventing breakage during lamination. The temperature of the second stage is increased to 140°C, allowing the first EVA film, the wide-width EVA film, and the POE film to fully melt, increasing the first EVA film's fluidity. The cross-linking degree of VA film, wide-width EVA film, and POE film increases the adhesion between the glass layer and the cell assembly, between the cell assembly and the insulating strip, and between the backsheet and the cell assembly and the insulating strip. By adopting a two-stage segmented lamination process with gradually increasing pressure, the encapsulation film is fully melted, flowed, and cross-linked. This ensures that the film tightly wraps and fills each layer of material, while avoiding thermal shock and stress damage to the diode and solder joints. This ensures that the final laminate has uniform internal stress, a flat structure, and is robust and reliable. Attached Figure Description

[0036] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0037] Figure 1 This is a front view of the overall structure of the anti-shading solar photovoltaic module in this invention;

[0038] Figure 2 This is a schematic diagram of the overall structure of the first photovoltaic unit in this invention;

[0039] Figure 3 This is a schematic diagram of the overall structure of the second photovoltaic unit in this invention;

[0040] Figure 4 This is a rear view of the overall structure of the anti-shading solar photovoltaic module in this invention;

[0041] Figure 5 This is a schematic diagram of the overall structure of the component to be laminated in this invention;

[0042] The attached figures are labeled as follows:

[0043] First photovoltaic unit A, second photovoltaic unit B, photovoltaic frame 1, glass layer 11, POE film 12, photovoltaic cell 13, wide-width EVA film 14, insulating strip 15, first EVA film 16, back sheet 17, cell group 2, first cell group 21, second cell group 22, third cell group 23, fourth cell group 24, intermediate busbar 3, first intermediate busbar 31, second intermediate busbar 32, third intermediate busbar 33, fourth intermediate busbar 34, busbar group 4, first main busbar 41, second main busbar 42, third busbar 43, side strip group 5, first busbar 51, second busbar 52, diode 6, positive terminal junction box 7, negative terminal junction box 8. Detailed Implementation

[0044] See Figures 1 to 5This invention provides a shading-resistant solar photovoltaic module, comprising a photovoltaic frame 1, a backplate 17 and a light-transmitting glass layer 11 fixed within the photovoltaic frame 1, and a positive terminal junction box 7 and a negative terminal junction box 8 on the backplate 17; two symmetrically arranged power supply mechanisms are provided between the backplate 17 and the glass layer 11, with the positive terminal junction box 7 and the negative terminal junction box 8 positioned between the respective power supply mechanisms; each power supply mechanism includes at least one photovoltaic unit group, comprising a first photovoltaic unit A and a second photovoltaic unit B arranged side-by-side along the long side of the photovoltaic frame 1, and a busbar positioned between the first photovoltaic unit A and the second photovoltaic unit B. Group 4, the first photovoltaic unit A and the second photovoltaic unit B each include multiple groups of solar cell groups 2 arranged side by side and connected in series along the wide side of the photovoltaic frame 1. Each solar cell group 2 consists of multiple photovoltaic cells 13 connected in series by solder ribbons. The busbar group 4 includes a first main busbar 41 and a second main busbar 42 fixed on the back plate 17. Solar cell groups 2 located on one side are electrically connected to the first main busbar 41 by solder ribbons, and solar cell groups 2 located on the other side are electrically connected to the second main busbar 42 by solder ribbons. The back plate 17 is also provided with intermediate busbars 3 corresponding one-to-one with each solar cell group 2. The intermediate busbars 3 are arranged parallel to the long side of the photovoltaic frame 1. Each intermediate busbar 3 is located between the corresponding cell group 2 and the backplate 17, and is insulated from the corresponding cell group 2. The intermediate busbars 3 located on the back of the cell groups 2 at the two side edges are electrically connected to the first main busbar 41 and the second main busbar 42, respectively. The first main busbar 41 is electrically connected to the positive terminal junction box 7 through the corresponding intermediate busbar 3, and the second main busbar 42 is electrically connected to the negative terminal junction box 8 through the corresponding intermediate busbar 3. Each intermediate busbar 3 passing under each cell group 2 in the first photovoltaic unit A is equipped with a diode 6. Adjacent intermediate busbars 3 in the first photovoltaic unit A are... The diodes 6 are reverse-oriented. In each intermediate busbar 3 passing under the cell group 2 in the second photovoltaic unit B, except for the intermediate busbars 3 connected to the first main busbar 41 and the second main busbar 42 on both sides, the remaining intermediate busbars 3 are also equipped with diodes 6, and the diodes 6 on adjacent cell groups 2 are reverse-oriented. The corresponding diodes 6 in the first photovoltaic unit A and the second photovoltaic unit B are reverse-oriented. The first photovoltaic unit A and the second photovoltaic unit B are connected in parallel through the connection of one side of the intermediate busbar 3 to the first main busbar 41 and the connection of the other side of the intermediate busbar 3 to the second main busbar 42, forming a same-frequency reverse circuit.

[0045] Diode 6 is connected in parallel across each of the cell groups 2. During normal power generation, the voltage generated by the cell group 2 causes diode 6 to be in a reverse bias state, i.e., non-conducting. The current flows through the cell group 2 along the normal path. When a cell group 2 is shaded, the voltage drops or even becomes negative. The diode 6 connected in parallel with it turns forward biased and conducts. The current flows from the adjacent normal cell group 2 around the shaded cell group 2, through diode 6 and the intermediate busbar 3, thus avoiding hot spot effect and preventing a significant drop in overall voltage.

[0046] The first photovoltaic unit A and the second photovoltaic unit B each include a first cell group 21, a second cell group 22, a third cell group 23, and a fourth cell group 24 arranged side-by-side and connected in series along the wide side of the photovoltaic frame 1. The busbar group 4 also includes a third busbar 43 disposed between the first main busbar 41 and the second main busbar 42. Side band groups 5 are also provided on both sides of the first photovoltaic unit A and the second photovoltaic unit B. The side band groups 5 include a first busbar 51 spanning the first cell group 21 and the second cell group 22, and a second busbar 52 spanning the third cell group 23 and the fourth cell group 24. The two ends of the first cell group 21 are connected to the busbar. The first battery cell group 21, the second battery cell group 22, the third battery cell group 23, and the fourth battery cell group 24 are electrically connected to the first busbar 41 and the first busbar 51 respectively via solder ribbons. The two ends of the second battery cell group 22 are electrically connected to the first busbar 51 and the third busbar 43 respectively via solder ribbons. The two ends of the third battery cell group 23 are electrically connected to the third busbar 43 and the second busbar 52 respectively via solder ribbons. The two ends of the fourth battery cell group 24 are electrically connected to the second busbar 52 and the second busbar 42 respectively via solder ribbons. The first battery cell group 21, the second battery cell group 22, the third battery cell group 23, and the fourth battery cell group 24 are connected in series with the first busbar 41, the first busbar 51, the third busbar 43, the second busbar 52, and the second busbar 42.

[0047] The backplate 17 is provided with a first intermediate busbar 31 corresponding to the first cell group 21, a second intermediate busbar 32 corresponding to the second cell group 22, a third intermediate busbar 33 corresponding to the third cell group 23, and a fourth intermediate busbar 34 corresponding to the fourth cell group 24. The first intermediate busbar 31 is electrically connected in sequence to the first busbar 51, the first main busbar 41, and the positive terminal junction box 7 of the first photovoltaic unit A. The second intermediate busbar 32 is electrically connected in sequence to the first busbar 51, the third busbar 43, the first busbar 51 of the second photovoltaic unit B, and the positive terminal junction box 7 of the first photovoltaic unit A. The third intermediate busbar 33 is electrically connected in sequence to the second busbar 52, the third busbar 43, the second busbar 52 of the second photovoltaic unit B, and the negative terminal junction box 8 of the first photovoltaic unit A. The fourth intermediate busbar 34 is electrically connected in sequence to the second busbar 52, the third busbar 43, and the negative terminal junction box 8 of the first photovoltaic unit A.

[0048] By configuring an independent intermediate busbar 3 for each cell group 2, namely the first intermediate busbar 31, the second intermediate busbar 32, the third intermediate busbar 33 and the fourth intermediate busbar 34, and establishing a specific electrical connection relationship, independent monitoring and protection of the working status of each cell group 2 is realized. When a cell group 2 malfunctions due to shading, its corresponding diode 6 immediately intervenes, while the current of other normally operating units remains undisturbed. This controls the negative impact of shading within the smallest unit and preserves the power generation capacity of the module to the maximum extent.

[0049] Both sides of the positive terminal box 7 and the negative terminal box 8 are provided with connecting busbars. The connecting busbar on one side of the positive terminal box 7 is connected to the first intermediate busbar 31, and the connecting busbar on the other side of the positive terminal box 7 is connected to the second intermediate busbar 32. The connecting busbar on one side of the negative terminal box 8 is connected to the third intermediate busbar 33, and the connecting busbar on the other side of the negative terminal box 8 is connected to the fourth intermediate busbar 34.

[0050] By setting connecting busbars on both sides of the positive terminal box 7 and the negative terminal box 8, and connecting them to each intermediate busbar 3 respectively, a multi-point parallel current lead-out structure is formed, which significantly reduces the current density at the terminal box, reduces the heat generation inside the terminal box, and improves the operational safety and long-term reliability of the component under high current and high power conditions.

[0051] Each diode 6 is evenly distributed on the intermediate bus 3 along the extension direction of the intermediate bus 3, and is fixedly connected to the intermediate bus 3 by welding.

[0052] By evenly distributing diodes 6 along the central busbar 3, localized component accumulation is avoided. Compared to the traditional approach of concentrating all diodes 6 in the junction box, this distributed layout significantly increases the heat dissipation area, allowing the heat generated by diodes 6 to be quickly dissipated to the external environment through the backplate 17, effectively reducing the internal operating temperature, thereby increasing power generation and extending service life.

[0053] After the positive terminal box 7 and the negative terminal box 8 are connected to the external energy storage battery:

[0054] The current flow of the first photovoltaic unit A is as follows: the current flows from one end of the positive terminal junction box 7 through the connecting busbar to the first intermediate busbar 31, then from the first intermediate busbar 31 to the first main busbar 41, then from the first main busbar 41 to the first cell group 21 of the first photovoltaic unit A, then sequentially to the first busbar 51, the second cell group 22, the third busbar 43, the third cell group 23, the second busbar 52 of the first photovoltaic unit A, and the fourth cell group 24, then from the fourth cell group 24 to the second main busbar 42, and then through the fourth intermediate busbar 34 and the connecting busbar to the negative terminal junction box 8;

[0055] The current flow of the second photovoltaic unit B is as follows: the current flows from one end of the positive terminal junction box 7 through the connecting busbar to the first intermediate busbar 31, then from the first intermediate busbar 31 to the first main busbar 41, then from the first main busbar 41 to the first cell group 21 of the second photovoltaic unit B, then sequentially to the first busbar 51, the second cell group 22, the third busbar 43, the third cell group 23, the second busbar 52 of the second photovoltaic unit B, and the fourth cell group 24, then from the fourth cell group 24 to the second main busbar 42, and then through the fourth intermediate busbar 34 and the connecting busbar to the negative terminal junction box 8;

[0056] The currents of the first photovoltaic unit A and the second photovoltaic unit B are shunted from the first main busbar 41. After shunting, the currents of the first photovoltaic unit A and the second photovoltaic unit B are symmetrical and reversed, and then converge from the second main busbar 42 to flow to the negative terminal box 8. This realizes a parallel circuit with the same frequency and opposite direction. When any cell group 2 is shaded, it can accurately block the reverse current of the shaded unit, completely eliminate the hot spot effect, overcome the defect of the traditional diode 6 scheme that causes the overall output voltage of the module to drop by one-third due to unidirectional conduction, ensure the voltage stability of the photovoltaic module, and thus ensure efficient charging of the energy storage battery.

[0057] The backplate 17 is provided with mounting grooves corresponding to each intermediate busbar 3. The backplate 17 is covered with a first EVA film 16, which extends along the contour of the backplate 17. The intermediate busbar 3, on which multiple diodes 6 are fixed, is fixed in the mounting groove through the first EVA film 16.

[0058] By setting a mounting groove on the back plate 17 and using the first EVA film 16 to fix the intermediate busbar 3 with diode 6 in the mounting groove, the diode 6 is accurately positioned and effectively encapsulated. The EVA film has good fluidity and adhesion after lamination, ensuring that the diode 6 does not shift during long-term use, while also ensuring electrical insulation safety.

[0059] An insulating strip 15 is also provided in the mounting groove, and the insulating strip 15 is pressed against the intermediate busbar 3.

[0060] By adding an insulating strip 15 in the mounting groove and pressing it against the intermediate busbar 3 after lamination, the electrical isolation between the intermediate busbar 3 and the battery cell pack 2 is further enhanced, effectively preventing the risk of leakage. At the same time, the physical pressing effect of the insulating strip 15 enhances the positional stability of the intermediate busbar 3 during the lamination process.

[0061] A wide EVA film 14 is provided between the battery cell assembly 2 and the insulating strip 15. The width of the wide EVA film 14 is greater than the width of the insulating strip 15. A POE film 12 is provided between the battery cell assembly 2 and the glass layer 11. The battery cell assembly 2 is fixedly connected to the insulating strip 15 through the wide EVA film 14, and the glass layer 11 is fixedly connected to the battery cell assembly 2 through the POE film 12.

[0062] The wide-width EVA film 14 provides stronger adhesion and stress buffering, protecting the fragile photovoltaic cells 13; while the POE film 12 demonstrates its excellent anti-aging and insulation properties, improving the weather resistance and safety of the module.

[0063] The present invention also provides a molding process for the aforementioned anti-shading solar photovoltaic module, comprising the following steps:

[0064] P1. Solder the corresponding number of diodes 6 onto each intermediate busbar;

[0065] P2. Connect each photovoltaic cell 13 in the cell group 2 in series to form the complete cell group 2.

[0066] P3. Lay POE film 12 on glass layer 11;

[0067] P4. Place the connected battery cell groups 2 sequentially on the POE film 12, adjust the spacing between the battery cell groups 2, and fix them with tape.

[0068] P5. Place a wide EVA film 14 with a width greater than the insulating strip 15 on each battery cell group 2.

[0069] P6. Place the intermediate busbar 3, which is soldered to each diode 6, on the insulating strip 15 and fix it with tape;

[0070] P7. Lay the first EVA film 16 on each battery cell group 2, insulating strip 15 and each intermediate busbar 3, and wrap the battery cell group 2, insulating strip 15 and intermediate busbar 3 between the first EVA film 16 and the glass layer 11.

[0071] P8. Lay the backing plate 17 on the first EVA film 16, and embed the insulating strip 15 and the intermediate busbar 3 into the mounting groove to form the part to be laminated.

[0072] P9. Place the part to be laminated into the laminator and form a laminate by segmented lamination;

[0073] P10. After lamination, the laminated component is removed from the laminator and cooled to form a complete solar panel.

[0074] The segmented lamination is divided into two stages. The temperature of the first stage of lamination is 110±3℃, and the temperature of the second stage of lamination is 140±3℃. The lamination pressure gradually increases from -80MPa to -35MPa.

[0075] The lamination temperature of the first stage is set to 110℃. The first EVA film 16, the wide EVA film 14, and the POE film 12 melt slowly at this temperature, resulting in low fluidity. Through slow melting, the gaps between the materials can be filled, thereby reducing the impact on each photovoltaic cell 13. Each photovoltaic cell 13 will not break during the lamination process. The temperature of the second stage is increased to 140℃, which allows the first EVA film 16, the wide EVA film 14, and the POE film 12 to melt fully, increasing the cross-linking degree of the first EVA film 16, the wide EVA film 14, and the POE film 12. At the same time, it increases the adhesion between the glass layer 11 and the cell group 2, between the cell group 2 and the insulating strip 15, and between the back sheet 17 and the cell group 2 and the insulating strip 15.

[0076] By adopting a two-stage segmented lamination process with gradually increasing pressure, the encapsulating film is fully melted, flowed, and cross-linked. The gradual temperature and pressure curves ensure that the film tightly wraps and fills each layer of material, while avoiding thermal shock and stress damage to diode 6 and solder ribbon connection points. This ensures that the final laminate has uniform internal stress, a flat structure, and is robust and reliable.

[0077] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are 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 solar photovoltaic module designed to prevent shading, comprising a photovoltaic frame, a back panel and a glass layer for light transmission fixed within the photovoltaic frame, and a positive terminal junction box and a negative terminal junction box provided on the back panel; characterized in that: Two symmetrically arranged power supply mechanisms are provided between the back panel and the glass layer. A positive terminal box and a negative terminal box are located between each power supply mechanism. Each power supply mechanism includes at least one photovoltaic unit group. The photovoltaic unit group includes a first photovoltaic unit and a second photovoltaic unit arranged side-by-side along the long side of the photovoltaic frame, and a busbar group located between the first and second photovoltaic units. Each first and second photovoltaic unit includes multiple groups of solar cells arranged side-by-side and connected in series along the wide side of the photovoltaic frame. Each solar cell group consists of multiple photovoltaic cells connected in series by solder strips. The busbar group includes a first main busbar and a second main busbar fixed to the back panel. Solar cells on one side of each solar cell group are electrically connected to the first main busbar via solder strips, and solar cells on the other side are electrically connected to the second main busbar via solder strips. The back panel also has intermediate busbars corresponding to each solar cell group. Each intermediate busbar is parallel to the long side of the photovoltaic frame and is located between the corresponding solar cells. The intermediate busbars located between the cell array and the backsheet, and insulated from the corresponding cell arrays, are electrically connected to the first main busbar and the second main busbar respectively. The first main busbar is electrically connected to the positive terminal box through the corresponding intermediate busbar, and the second main busbar is electrically connected to the negative terminal box through the corresponding intermediate busbar. Each intermediate busbar passing under each cell array in the first photovoltaic unit is equipped with a diode. Adjacent diodes in the first photovoltaic unit are reverse-oriented. In each intermediate busbar passing under the cell array in the second photovoltaic unit, except for the intermediate busbars connected to the first and second main busbars on both sides, diodes are also provided on the remaining intermediate busbars. The diodes on adjacent cell arrays are reverse-oriented. The corresponding diodes in the first photovoltaic unit and the second photovoltaic unit are reverse-oriented. The first photovoltaic unit and the second photovoltaic unit are connected in parallel through the connection of one intermediate busbar to the first main busbar and the connection of the other intermediate busbar to the second main busbar, forming a same-frequency reverse circuit.

2. The anti-shading solar photovoltaic module according to claim 1, characterized in that: Both the first and second photovoltaic units include a first cell group, a second cell group, a third cell group, and a fourth cell group arranged side-by-side and connected in series along the wide side of the photovoltaic frame. The busbar group also includes a third busbar positioned between the first and second main busbars. Side band groups are also provided on both sides of the first and second photovoltaic units. These side band groups include a first busbar spanning the first and second cell groups, and a second busbar spanning the third and fourth cell groups. The first, second, third, and fourth battery cell groups are electrically connected to the first main bus and the first bus via solder strips. The two ends of the second battery cell group are electrically connected to the first bus and the third bus via solder strips. The two ends of the third battery cell group are electrically connected to the third bus and the second bus via solder strips. The two ends of the fourth battery cell group are electrically connected to the second bus and the second main bus via solder strips. The first, second, third, and fourth battery cell groups are connected in series with the first main bus, the first bus, the third bus, the second bus, and the second main bus.

3. A solar photovoltaic module for preventing shading according to claim 2, characterized in that: The backplate is provided with a first intermediate busbar corresponding to the first battery cell group, a second intermediate busbar corresponding to the second battery cell group, a third intermediate busbar corresponding to the third battery cell group, and a fourth intermediate busbar corresponding to the fourth battery cell group. The first intermediate busbar is electrically connected in sequence to the first busbar, the first main busbar, and the positive terminal box of the first photovoltaic unit. The second intermediate busbar is electrically connected in sequence to the first busbar, the third busbar, the first busbar of the second photovoltaic unit, and the positive terminal box of the first photovoltaic unit. The third intermediate busbar is electrically connected in sequence to the second busbar, the third busbar, the second busbar of the second photovoltaic unit, and the negative terminal box of the first photovoltaic unit. The fourth intermediate busbar is electrically connected in sequence to the second busbar, the third busbar, and the negative terminal box of the first photovoltaic unit.

4. A solar photovoltaic module for preventing shading according to claim 3, characterized in that: Both sides of the positive terminal box and the negative terminal box are provided with connecting busbars. The connecting busbar on one side of the positive terminal box is connected to the first intermediate busbar, the connecting busbar on the other side of the positive terminal box is connected to the second intermediate busbar, the connecting busbar on one side of the negative terminal box is connected to the third intermediate busbar, and the connecting busbar on the other side of the negative terminal box is connected to the fourth intermediate busbar.

5. A solar photovoltaic module for preventing shading according to claim 4, characterized in that: Each diode is evenly distributed on the intermediate busbar along the extension direction of the intermediate busbar and is fixedly connected to the intermediate busbar by welding.

6. A solar photovoltaic module for preventing shading according to claim 5, characterized in that: The backplate is provided with mounting slots corresponding to each intermediate busbar. The backplate is covered with a first EVA film, which extends along the contour of the backplate. The intermediate busbars with multiple diodes are fixed in the mounting slots by the first EVA film.

7. A solar photovoltaic module for preventing shading according to claim 6, characterized in that: An insulating strip is also provided inside the mounting groove, and the insulating strip is pressed against the intermediate busbar.

8. A solar photovoltaic module for preventing shading according to claim 7, characterized in that: A wide EVA film is provided between the battery cell assembly and the insulating strip. The width of the wide EVA film is greater than the width of the insulating strip. A POE film is provided between the battery cell assembly and the glass layer. The battery cell assembly is fixedly connected to the insulating strip through the wide EVA film, and the glass layer is fixedly connected to the battery cell assembly through the POE film.

9. The molding process of the anti-shading solar photovoltaic module according to claim 8, characterized in that... Includes the following steps: P1. Solder the corresponding number of diodes onto each intermediate busbar; P2. Connect the individual photovoltaic cells in the cell array in series to form a complete cell array. P3. Lay POE film on the glass layer; P4. Place the connected battery cell groups on the POE film in sequence, adjust the spacing between the battery cell groups, and fix them with tape. P5. Place a wide EVA film, wider than the insulating strip, on each battery cell group; P6. Place the intermediate busbars that are soldered to each diode on the insulating strip and fix them with tape; P7. Lay the first EVA film on each battery cell group, insulating strip and intermediate busbar, and wrap the battery cell group, insulating strip and intermediate busbar between the first EVA film and the glass layer. P8. Lay the backing plate on the first EVA film and embed the insulating strip and intermediate busbar into the mounting groove to form the part to be laminated. P9. Place the part to be laminated into the laminator and form a laminate by segmented lamination; P10. After lamination, the laminated component is removed from the laminator and cooled to form a complete solar panel.

10. The molding process according to claim 9, characterized in that: The segmented lamination is divided into two stages. The temperature of the first stage of lamination is 110±3℃, and the temperature of the second stage of lamination is 140±3℃. The lamination pressure gradually increases from -80MPa to -35MPa.

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