Terminal box set

Abstract

To provide a terminal box set that can easily connect the terminal boxes of adjacent flexible solar panels without a connection cable when connecting a plurality of flexible solar panels in series and extracting generated power from the panels. [Solution] A terminal box set for electrically connecting adjacent flexible solar panels, intended to have a terminal box provided at each of the opposing ends of adjacent flexible solar panels, one terminal box being a male terminal box with a protruding terminal portion and the other terminal box being a female terminal box with a receiving terminal portion that receives the protruding terminal portion, and configured so that the electrical connection between the male and female terminal boxes can be maintained by inserting and fixing the protruding terminal portion into the receiving terminal portion.

Description

[Technical Field]

[0001] The present invention relates to a terminal box set for electrically connecting adjacent flexible solar panels without the use of cables. [Background technology]

[0002] In a power generation system using solar panels, a large number of rigid solar panels are prepared and connected in series to extract the required power (see Patent Documents 1 to 3). Specifically, as shown in Fig. 1, for this series connection, a terminal box B is attached to the back surface of the rigid solar panel P, and the terminal boxes B of adjacent solar panels P are electrically connected via an external connection cable K.

[0003] Conventional rigid solar panels are large and heavy, which poses the problem of requiring careful consideration of the installation location and the landscape. In recent years, flexible solar panels have been proposed as an alternative, as they are easy to move and install (see Patent Document 4). Unlike conventional rigid solar panels, flexible solar panels are thin and light, and are easily bendable, making them easy to carry and install. When installing multiple flexible solar panels, just like conventional heavy rigid solar panels, it is necessary to connect each panel in series to extract power. In this case, as in Figure 1, the terminal boxes B of adjacent flexible solar panels F are electrically connected via an external connection cable K (see Figure 2).

[0004] However, for lightweight, foldable flexible solar panels, the connection cables are bulky when transporting them, and each time the terminal boxes of adjacent flexible solar panels are connected or disconnected, the connection cables must also be connected or disconnected to the terminal boxes, making installation cumbersome. Furthermore, for flexible solar panels installed on a small scale, connecting adjacent panels in series with a connection cable can result in a high rate of electrical loss. Furthermore, for simple flexible solar panels, the presence of connection cables is a factor that increases costs. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-103567 [Patent Document 2] Japanese Patent Application Laid-Open No. 2014-90007 [Patent Document 3] Japanese Patent Application Laid-Open No. 2016-111849 [Patent Document 4] Japanese Patent Application Laid-Open No. 2017-175019 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention was devised in view of the current state of the prior art described above, and its purpose is to provide a terminal box set that can easily and safely connect the terminal boxes of adjacent flexible solar panels without a connection cable when connecting multiple flexible solar panels in series to extract the generated power, and a flexible solar panel using the same. [Means for solving the problem]

[0007] In order to achieve the above-mentioned object, the inventors have conducted extensive research into the structure of a terminal box suitable for electrically connecting adjacent flexible solar panels without using a connection cable, and as a result have found that the electrical connection of the terminal boxes of adjacent flexible solar panels can be easily and safely maintained by (i) providing a male terminal box and a female terminal box at each opposing end of adjacent flexible solar panels, and inserting and fixing the protruding terminal portion of the male terminal box of one flexible solar panel into the receiving terminal portion of the female terminal box of the other flexible solar panel, or (ii) providing terminal boxes at each opposing end of adjacent flexible solar panels so that the exposed terminals face each other, bringing the exposed terminals of each terminal box into contact with each other, and fixing both terminal boxes together as a unit, thereby completing the present invention.

[0008] That is, the present invention was completed based on the above findings and has the following features (1) to (9). (1) A terminal box set for electrically connecting adjacent flexible solar panels, intended to have terminal boxes provided at the opposing ends of adjacent flexible solar panels, one terminal box being a male terminal box having a protruding terminal portion and the other terminal box being a female terminal box having a receiving terminal portion for receiving the protruding terminal portion, characterized in that the terminal box set is configured so that the electrical connection between the male terminal box and the female terminal box can be maintained by inserting and fixing the protruding terminal portion of the male terminal box into the receiving terminal portion of the female terminal box. (2) A terminal box set as described in (1), characterized in that the male terminal box can be released from the female terminal box by releasing the fixation of the protruding terminal portion of the male terminal box to the receiving terminal portion of the female terminal box. (3) A flexible solar panel having an approximately rectangular shape and a terminal box set according to (1) or (2) provided on the back side of the light receiving surface, characterized in that a male terminal box is provided at one corner of the end portion that constitutes the same side of the flexible solar panel, and a female terminal box is provided at the other corner. (4) A flexible solar panel set having at least two or more flexible solar panels described in (3), characterized in that when the protruding terminal portion of the male terminal box of one flexible solar panel is inserted into the receiving terminal portion of the female terminal box of another adjacent flexible solar panel, the adjacent flexible solar panels are configured to be in close contact with each other without any gaps. (5) A terminal box set for electrically connecting adjacent flexible solar panels, wherein a terminal box is intended to be provided at each of the opposing ends of adjacent flexible solar panels, and each terminal box provided on adjacent flexible solar panels has exposed terminals facing each other, and the exposed terminals of each terminal box are brought into contact with each other and both terminal boxes are fixed together, thereby maintaining the electrical connection of both terminal boxes. (6) A terminal box set according to (5), characterized in that the terminal boxes are configured so that they can be released from each other by releasing the integral fixation of the terminal boxes. (7) A flexible solar panel having an approximately rectangular flexible solar panel with a terminal box set according to (5) or (6) provided on the back side of the light receiving surface, characterized in that a terminal box is provided at each end of the opposing sides of the flexible solar panel, and the terminals of each terminal box are exposed towards the outside of the flexible solar panel. (8) A terminal box set as described in (1) or (5), characterized in that the terminal box has a perforated tab that protrudes outward from the flexible solar panel, and is configured so that the end of the flexible solar panel can be fixed by fastening it to a fixed object with a screw or string through the hole in the perforated tab. (9) A terminal box set according to (1) or (5), characterized in that a bypass diode or a reverse current prevention diode is built into the terminal box. [Effects of the Invention]

[0009] The terminal box set of the present invention can connect terminal boxes on adjacent flexible solar panels without using cables, making it easy to carry and install, low-cost, and free from electrical loss due to cables. Furthermore, by providing the terminal box set of the present invention on the back side and at the end of the light-receiving surface of the flexible solar panel, it is possible to minimize the reduction in the light-receiving area and facilitate folding and storage of the flexible solar panel. Furthermore, even if the terminal box expands at high temperatures when the terminal box set of the present invention is used to electrically connect the terminal boxes of adjacent flexible solar panels, the flexibility of the flexible solar panels allows the terminal box to absorb the stress of thermal expansion, preventing deformation or damage of the terminal box due to the external environment, as occurs when the terminal box is used with rigid solar panels. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of an example of electrically connecting a terminal box of a conventional rigid solar panel. [Figure 2] FIG. 2 is a schematic diagram of an example of electrically connecting a terminal box of a conventional flexible solar panel. [Figure 3] FIG. 3 is a schematic diagram of an example of an installation example of a terminal box set of the present invention for electrically connecting adjacent flexible solar panels to each other. [Figure 4]FIG. 4 is a detailed schematic diagram of an example in which terminal boxes of the terminal box set of the present invention are fixed in an electrically connected state in adjacent flexible solar panels. [Figure 5] Figure 5(a) is a detailed schematic diagram of an example in which the fixing of each terminal box of the terminal box set in Figure 4 has been released. Figure 5(b) shows the AA cross-sectional view and the BB cross-sectional view of Figure 5(a) on the left and right, respectively. [Figure 6] Figure 6(a) is a schematic diagram of an example in which a bypass diode is provided in a terminal box, Figure 6(b) is a schematic diagram of an example in which a backflow prevention diode is provided in a terminal box, and Figure 6(c) is a schematic diagram of an example in which a diode is not provided in the terminal box. [Figure 7] FIG. 7 is a schematic view of an example of a perforated tab provided in the terminal box of the present invention. [Figure 8] FIG. 8 is a schematic diagram of another example of installation of a terminal box set of the present invention for electrically connecting adjacent flexible solar panels together. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the terminal box set of the present invention and a flexible solar panel provided with the same will be described with reference to the drawings, but the present invention is not limited to these.

[0012] The terminal box set of the present invention is for electrically connecting adjacent flexible solar panels and contributes to extracting the power generated by each flexible solar panel through a series connection. The terminal box set of the present invention does not require the use of a connection cable for electrically connecting the terminal boxes, so adjacent flexible solar panels can be installed close to each other.

[0013] The terminal box set of the present invention is not intended to be installed on conventional rigid solar panels, which are thick, hard, and heavy and are fixed using a mounting base, but is intended to be installed on flexible solar panels. Flexible solar panels, unlike conventional rigid solar panels, are made of flexible materials, and are therefore thin and light, and their flexibility allows them to be bent or folded. Therefore, flexible solar panels are highly portable and storable, and can be easily brought to various locations and installed.

[0014] Flexible solar panels generally consist of solar cells that convert solar energy into electricity, a surface protection layer that protects the solar cells from external impacts and ultraviolet rays, a sealing film filled between the solar cells, and a backsheet that protects the back surface of the flexible solar panel, and the present invention can have a similar configuration. Perovskite crystal structure cells, thin-film silicon cells, etc. are used as solar cells for flexible solar panels, and these can be made by coating or printing materials, allowing for mass production at low cost.

[0015] FIG. 3 shows a schematic diagram of an example of the installation of a terminal box set of the present invention for electrically connecting adjacent flexible solar panels. In FIG. 3, 1 denotes flexible solar panels, which are shown adjacent to each other on the left and right. Flexible solar panels are preferably approximately rectangular because this effectively increases the light-receiving area when multiple solar panels are arranged adjacently. 2 denotes a male terminal box constituting one side of the terminal box set. Male terminal box 2 has a protruding terminal portion 4 that protrudes outward. 3 denotes a female terminal box constituting the other side of the terminal box set. Female terminal box 3 has a receiving terminal portion 5 that accepts the protruding terminal portion 4 of male terminal box 2. The receiving terminal portion 5 may be located within the female terminal box or may protrude from the female terminal box. The terminal box set of the present invention is composed of a male terminal box 2 having a protruding terminal portion 4 and a female terminal box 3 having a receiving terminal portion 5 that accepts the protruding terminal portion 4. 3, each terminal box of the terminal box set is provided at an end on the back side of the light-receiving surface of a rectangular flexible solar panel 1. Specifically, a male terminal box 2 is provided at one corner of the end that constitutes the same side of the rectangular flexible solar panel, and a female terminal box 3 is provided at the other corner. When two rectangular flexible solar panels are placed adjacent to each other and electrically connected using the male terminal box 2 and female terminal box 3 of the terminal box set, for example, as shown in the bottom center of FIG. 3, the male terminal box 2 and female terminal box 3 are installed at opposite ends of the adjacent flexible solar panels, and the protruding terminal portion 4 of the male terminal box 2 is inserted into the receiving terminal portion 5 of the female terminal box 3 and fixed in this state to maintain the electrical connection between the male terminal box 2 and the female terminal box 3.In Figure 3, there are gaps between adjacent flexible solar panels. However, by, for example, (i) positioning the male terminal box 2 and female terminal box 3 of adjacent flexible solar panels further inward than the positions shown in Figure 3, or (ii) providing the receiving terminal portion 5 within the female terminal box 3 so that the protruding terminal portion 4 of the male terminal box 2 fits completely inside the receiving terminal portion 5, it is possible to configure the adjacent flexible solar panels so that they are in close contact with each other without any gaps when the protruding terminal portion 4 of the male terminal box 2 of one flexible solar panel is inserted into the receiving terminal portion 5 of the female terminal box 3 of another adjacent flexible solar panel. This prevents sunlight from passing between adjacent flexible solar panels. Such an embodiment allows flexible solar panels to be used not only for solar power generation but also as weed control sheets to block sunlight and suppress weed growth.

[0016] Figure 4 is an enlarged view of the bottom center of Figure 3, showing the state in which the electrical connection between the male terminal box 2 and the female terminal box 3 is maintained, along with a detailed schematic of the interior of the terminal box. Figure 5(a) shows the state in which the male terminal box 2 and the female terminal box 3 in Figure 4 are released after their electrical connection has been released, and Figure 5(b) shows the AA and BB cross-sectional views of Figure 5(a), respectively. In Figures 4 and 5, 1 denotes a flexible solar panel, 2 denotes a male terminal box, 3 denotes a female terminal box, 4 denotes a protruding terminal portion, 5 denotes a receiving terminal portion, 6 denotes a fixing claw, 7 denotes a terminal board, and 8 denotes a diode. In the male terminal box 2, the protruding terminal portion 4 is connected to the terminal board 7, and in the female terminal box 3, the receiving terminal portion 5 is connected to the terminal board 7. As can be seen from Figure 4, which shows the electrically connected state of the male terminal box 2 and the female terminal box 3, in this state the protruding terminal portion 4 of the male terminal box 2 is inserted into the receiving terminal portion 5 of the female terminal box 3, and the outside of the protruding terminal portion 4 is in contact with the inside of the receiving terminal portion 5. Furthermore, as can be further seen from Figures 5(a) and (b), which show the male terminal box 2 and the female terminal box 3 in a released state where they are not in electrical contact with each other, there is a space between the protruding terminal portion 4 of the male terminal box 2 and the housing portion surrounding it, and there is no space between the receiving terminal portion 5 of the female terminal box 3 and the housing portion surrounding it, and the outside of the protruding terminal portion 4 is inserted into the inside of the receiving terminal portion 5, and the protruding terminal portion 5 and the housing portion surrounding it are inserted into the space between the receiving terminal portion 4 and the housing portion surrounding it, thereby establishing contact between the protruding terminal portion 4 and the receiving terminal portion 5.

[0017] To safely maintain the electrical contact between the protruding terminals 4 and the receiving terminals 5, it is preferable to secure them together using a securing mechanism. The securing mechanism is not particularly limited, and any conventionally known means can be used as long as it achieves its purpose. For example, as shown in FIGS. 4 and 5, securing claws 6 protruding from the female terminal box 3 on both sides of the receiving terminals 5 can be provided, and these securing claws 6 can be engaged with the outer portions of the protruding terminals 4 of the male terminal box 2 to secure them together. Alternatively, they can be secured together using a securing mechanism such as a fixture 14 shown in FIG. 8 (described later). These securing mechanisms make it difficult for the protruding terminals 4 of the male terminal box 2 and the receiving terminals 5 of the female terminal box 3 to come off, thereby safely maintaining the electrical connection between them. The securing mechanism can be released by removing the tips of the securing claws 6. To explain the flow of current using the schematic diagram in Figure 4, the current generated by the flexible solar panel 1 on the left side is taken out to the upper terminal board 7 of the female terminal box 3, and flows from the upper terminal board 7 through the diode 8 to the lower terminal board 7 and receiving terminal portion 5, and then flows to the protruding terminal portion 4 of the male terminal box 2, the lower terminal board 7, the diode 8, and the upper terminal board 7, and then to the flexible solar panel 1 on the right side.

[0018] FIG. 6(a) is a schematic diagram of an example in which a bypass diode is provided in a terminal box, FIG. 6(b) is a schematic diagram of an example in which a backflow prevention diode is provided in a terminal box, and FIG. 6(c) is a schematic diagram of an example in which a diode is not provided in a terminal box. The provision of a diode in the terminal box of the present invention, as shown in FIG. 6(c), is not required. Diodes can be provided as shown in FIGS. 6(a) and 6(b) depending on the purpose. A diode is a semiconductor element through which current flows when a forward voltage is applied. A bypass diode only passes current when an abnormality occurs in the power generation of the flexible solar panel due to shadowing or a malfunction. A backflow prevention diode always passes current even in the event of an abnormality, as long as reverse current can be prevented. In the example shown in FIG. 6(a) with a bypass diode, when the flexible solar panel is normal, the generated current flows through the lower positive bus bar 9 to the lower terminal board 7 and receiving terminal 5. However, when an abnormality occurs, the generated current flows through the upper negative bus bar 10 to the upper terminal board 7, diode 8, lower terminal board 7, and receiving terminal 5. In the example of Fig. 6(b) where a backflow prevention diode is provided, the generated current flows through the positive bus bar 9, to the upper terminal board 7, the diode, the lower terminal board 7, and the receiving terminal part 5. In the terminal box where no diode is provided as shown in Fig. 6(c), the generated current flows through the positive bus bar 9, to the terminal board 7, and the receiving terminal part 5.

[0019] Figure 7 is a schematic diagram of an example of a perforated tab provided on a terminal box set of the present invention. The male terminal box and female terminal box of the terminal box set of the present invention are fixed to the flexible solar panel with adhesive or sealant, double-sided tape, or screws, and when fixed in this manner, a perforated tab 11 can be provided that protrudes outward from the flexible solar panel 1, as shown in Figure 7. This perforated tab 11 can be fixed to a surrounding fixture with screws or string, allowing the end of the flexible solar panel to be stably fixed.

[0020] FIG. 8 is a schematic diagram illustrating a terminal box set according to the present invention, which is different from the terminal box sets shown in FIGS. 3 to 5, installed on adjacent flexible solar panels. In FIG. 8, 1 denotes a flexible solar panel, and 12 denotes a terminal box. The terminal boxes 12 are installed facing adjacent flexible solar panels 1. The interior of the terminal box 12 in FIG. 8 can have a structure similar to that of the terminal boxes shown in FIGS. 3 to 5, but terminals 13 extending from the internal terminal board are exposed on the exterior of each terminal box 11 and face each other. The facing exposed terminals 13 are brought close to each other as shown by the arrows, and after they come into contact, the two terminal boxes are fixed together. This fixing method is not particularly limited, and any conventionally known method can be used. For example, as shown in FIG. 8, the exposed terminals 13 of the two terminal boxes 12 can be brought close to each other and fixed by hooking fixtures 14 from above and below the two terminal boxes 12 as shown by the arrows. Release of the fixation can be easily achieved by removing the fixtures 14 from the two terminal boxes 12. The terminal box set of Figure 8 can appropriately adopt the internal configuration used in the terminal box sets of Figures 3 to 5 and configurations that can be applied to the terminal box sets of Figures 3 to 5 (such as the configurations of Figures 6 and 7), thereby being able to expect the same basic effects. [Industrial Applicability]

[0021] The terminal box set of the present invention is extremely useful for the flexible solar panel industry and its users, as it allows adjacent flexible solar panels to be placed close to each other and electrically connected easily and safely without using connection cables. [Explanation of symbols]

[0022] 1. Flexible solar panels 2 Male terminal box 3 Female terminal box 4 Protruding terminal part 5 Receptor terminal 6 Fixing claw 7 Terminal board 8. Diodes 9 positive busbars 10 Negative busbar 11 Perforated tab 12 Terminal box 13 terminals 14 Fixtures

Claims

1. A terminal box set for electrically connecting adjacent flexible solar panels, wherein a terminal box is intended to be provided at each of the opposing ends of adjacent flexible solar panels, one terminal box being a male terminal box having a protruding terminal portion and the other terminal box being a female terminal box having a receiving terminal portion that accepts the protruding terminal portion, and wherein the terminal box is configured so that the electrical connection between the male terminal box and the female terminal box can be maintained by inserting and fixing the protruding terminal portion of the male terminal box into the receiving terminal portion of the female terminal box, and the terminal box has a perforated tab that protrudes outside the flexible solar panel, and is configured so that the end of the flexible solar panel can be fixed to a fixed object by passing the hole in the perforated tab through the tab and fixing it with a screw or string.

2. 2. The terminal box set according to claim 1, wherein the male terminal box is configured to be released from the female terminal box by releasing the fixation of the protruding terminal portion of the male terminal box to the receiving terminal portion of the female terminal box.

3. 3. A flexible solar panel having an approximately rectangular flexible solar panel in which the terminal box set according to claim 1 or 2 is provided on the back side of the light receiving surface, wherein a male terminal box is provided at one corner of the end portion constituting the same side of the flexible solar panel, and a female terminal box is provided at the other corner.

4. A flexible solar panel set having at least two or more flexible solar panels according to claim 3, characterized in that when the protruding terminal portion of the male terminal box of one flexible solar panel is inserted into the receiving terminal portion of the female terminal box of another adjacent flexible solar panel, the adjacent flexible solar panels are configured to be in close contact with each other without any gaps.

5. A terminal box set for electrically connecting adjacent flexible solar panels, wherein the terminal boxes are intended to be provided at the opposing ends of adjacent flexible solar panels, and the terminal boxes provided on adjacent flexible solar panels have exposed terminals facing each other, and are configured so that the electrical connection between the two terminal boxes can be maintained by bringing the exposed terminals of the terminal boxes into contact with each other and fixing the two terminal boxes together as a unit, and the terminal boxes have perforated tabs that protrude outward from the flexible solar panel, and are configured so that the ends of the flexible solar panels can be fixed by passing the holes in the perforated tabs through screws or strings to a fixed object.

6. 6. The terminal box set according to claim 5, wherein the terminal boxes are configured so that they can be released from each other by releasing the fixed terminal boxes from one another.

7. A flexible solar panel characterized in that the terminal box set according to claim 5 or 6 is provided on the back side of the light receiving surface of an approximately rectangular flexible solar panel, a terminal box is provided at each end of opposing sides of the flexible solar panel, and the terminals of each terminal box are exposed toward the outside of the flexible solar panel.

8. 6. The terminal box set according to claim 1, wherein a bypass diode or a backflow prevention diode is built into the terminal box.

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