External terminal box for solar battery module

Abstract

To provide an external terminal box that is disposed outside a next-generation type solar battery module and electrically connected thereto, without affecting the design of the solar battery module or the external terminal box, and increasing the freedom of the installation location, layout, and shape of the solar battery module.SOLUTION: An external terminal box 1 is configured to have a box body 2 provided outside a solar battery module X, and this box body 2 is provided with a pair of terminal boards 3, 3 electrically connected to electric wires X1, X1 extending from the solar battery module X and electrically connected to each other, and an input cable 6 and an output cable 7 electrically connected to each of the terminal boards 3, 3, extending outside the box body 2, and connectable to cables extending from other adjacent devices.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an external terminal box that is used when connecting solar cell modules that constitute a solar power generation system that directly converts solar energy into electrical energy, and in particular to an external terminal box that is not built into the solar cell module. [Background technology]

[0002] Photovoltaic power generation systems that utilize the power generated by solar cells as a power source for home and industrial use have been widely used. Conventionally, in photovoltaic power generation systems, electricity is supplied or transmitted to each electrical appliance mainly through an inverter or the like from a solar panel installed on the roof of a building or an open space. In this type of solar cell panel, a structure is generally adopted in which a large number of solar cell modules are laid out flush with each other, and the electrodes of each solar cell module are connected in series or in parallel through a terminal box (also called a junction box). Each solar cell module is configured to have a large number of cells electrically connected in series by a bus bar (electrode wire), and the bus bar is electrically connected to a terminal box provided inside the module (particularly on the back side of the module). Adjacent solar cell modules are connected to each other by electrically connecting electric wires extending from the respective terminal boxes through a connector (see Patent Document 1 and Patent Document 2).

[0003] Solar cell modules, which have been widely adopted up until now, are limited in their installation locations, such as the roofs and rooftops of buildings with high load-bearing capacity, or flat, vast areas of land, due to their heavy weight and square shape. In light of these issues and the social situation in which the expansion of renewable energy is being called for due to the international trend toward a sustainable society, development of next-generation film-type solar cells, such as perovskite solar cells, is underway with the aim of making it possible to efficiently install solar power generation systems on the exterior walls and windows of buildings, carport roofs, etc., even in urban areas where large-scale power generation facilities could not be installed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 5-343724 [Patent Document 2] Japanese Patent Application Publication No. 11-026035 Summary of the Invention [Problem to be solved by the invention]

[0005] Next-generation solar cells are expected to be thin, flexible, transparent or semi-transparent, and characterized by being able to be installed anywhere, and therefore are expected to be configured without a large, sturdy housing. For this reason, if a terminal box is placed inside or on the back of a next-generation solar cell module as in conventional solar cell modules, it is thought that there is a risk of impairing the design and power generation efficiency. In addition, placing a terminal box inside a next-generation solar cell module would also hinder the reduction of the manufacturing cost of the entire solar cell module.

[0006] Due to these circumstances, in order to accommodate next-generation solar cells, and taking into consideration design and manufacturing costs, a new issue has arisen as to how to resolve the issue of where to place the terminal box, which did not previously need to be considered.

[0007] Therefore, the present invention aims to solve the above-mentioned problems in response to next-generation film-type solar cells and their modules by adopting a configuration in which the terminal box is not located within the solar cell module, but is placed outside the solar cell module, and the electric wires drawn from the solar cell module are connected to the terminal box. [Means for solving the problem]

[0008] In other words, the external terminal box for a solar cell module of the present invention is used by being electrically connected to the outside of the solar cell module, and is characterized in that it has a box main body that is provided outside the solar cell module, and this box main body is provided with a pair of terminal plates that are electrically connected to the electric wires extending from the positive and negative electrodes of the solar cell module, respectively, and are electrically connected to each other, and input and output cables that are electrically connected to each of the terminal plates, extend outside the box main body, and can be connected to cables extending from other adjacent equipment.

[0009] By connecting such an external terminal box to a solar cell module, the terminal box is arranged outside the solar cell module, and the positive and negative electrodes extending from the solar cell module are connected to the respective terminal plates in the box body, and further, input and output cables are drawn from each terminal plate and connected to the cables of other devices such as adjacent external terminal boxes, so that the terminal box has the same functions as the terminal box arranged on the back side of the conventional solar cell module. Moreover, even if a transparent or semi-transparent one or a film type without a large housing is adopted as a next-generation solar cell module, the terminal box (box body) is externally attached, so that the design of the solar cell module itself is not impaired, and the freedom of the installation location, layout, and shape of the solar cell module can be increased. In addition, since the box body is externally attached, it is easy to reduce the size of the box body, so that the terminal box can be made less noticeable, and in this respect, the design of the solar cell module can be improved. Furthermore, in conventional solar cell modules, a large number of cells are connected in series with a bus bar, and the bus bar is then connected to a terminal box on the back side of the module, but in the next-generation solar cell module, the bus bar is no longer used to connect the module to the external terminal box, so the connection structure between the bus bar and the terminal box is simplified using electric wires, and in addition to simplifying the structures of both the solar cell module and the external terminal box, the work time can be shortened by eliminating the need for connection work such as soldering, which ultimately leads to a reduction in the manufacturing cost of the solar cell module itself. Note that if there is no adjacent solar cell module to be electrically connected, the input cable and output cable extended from the box body may be connected to other appropriate devices such as an adjacent power conditioner, a power distributor, a power storage device, and a power meter.

[0010] A pair of terminal boards arranged inside the box body of the external terminal box are electrically connected to each other, and when the terminal boards are connected to each other with a jumper wire, they can be used regardless of the input / output direction. However, when the terminal boards are connected to each other with a bypass diode, a usage method (connection method) that specifies the input / output direction can be adopted.

[0011] Furthermore, if an external terminal box is provided with a pair of connector-equipped wires that extend from a pair of terminal plates and can be connected to wires extending from the positive and negative electrodes of the solar cell module, and if connectors are provided at the ends of the input and output cables that extend from the pair of terminal plates, then in addition to connecting to the solar cell module, the connection work with other adjacent external terminal boxes can be simplified.

[0012] Conventionally, after connecting the bus bar to the terminal plate in the box body, the inside of the box body is filled with a resin molding material to provide waterproofing and protection when used outdoors, but this filling work is cumbersome. However, by making the terminal box external, as described above, the bus bar for connecting the solar cell module and the external terminal box is not required, and the conventional connection structure and connection work between the bus bar and the terminal plate are not required, so it is possible to fill the inside of the box body with the resin molding material in advance. A suitable configuration of the external terminal box with such a configuration can be one that has a molding part made of a resin molding material that is filled inside the box body and covers the pair of terminal plates, the pair of electric wires with connectors, the input cable, and the output cable inside the box body. Effect of the Invention

[0013] The external terminal box of the present invention can be used as a terminal box that can be externally connected to next-generation solar cell modules such as perovskite solar cells, and therefore can improve the freedom of shape and arrangement as well as the design of transparent, semi-transparent or film-type solar cell modules without reducing the power generation efficiency of the modules. In addition, there are great benefits in terms of simplifying the connection structure between the solar cell module and the terminal box and simplifying the connection work. [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is a perspective view showing an external terminal box according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a plan view showing an external terminal box according to the embodiment; [Diagram 3] FIG. 2 is a front view showing the external terminal box according to the embodiment; [Figure 4] FIG. 2 is a perspective view showing a usage example of the external terminal box according to the embodiment. [Diagram 5] FIG. 4 is a plan view showing an example of use of the external terminal box according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0016] The external terminal box 1 according to this embodiment is externally connected to a film-type solar cell module X as shown in Figs. 4 and 5. The type of solar cell module X is not limited, but a module such as a perovskite solar cell currently under development is assumed. This type of solar cell module X uses a bus bar that connects a large number of cells (not shown) in series, but is provided with a pair of electric wires X1, X1 that extend positive and negative electrodes connected to the cells from the solar cell module X. A male connector X1a and a female connector X1b are attached to each of the electric wires X1, X1 for electrical connection with the external terminal box 1.

[0017] 1, 2, and 3, an external terminal box 1 has a pair of terminal boards 3, 3 fixed inside a box body 2. The box body 2 is a hollow rectangular resin case that is open upward, and two terminal boards 3, 3 are fixed to the bottom surface of the box body 2 in the longitudinal direction with a predetermined distance between them. In this embodiment, the terminal boards 3, 3 are connected to each other by a bypass diode 4, and the current flow direction is determined, but if a jumper wire is used instead of the bypass diode 4, a usage method that does not matter the current flow direction can be adopted.

[0018] The pair of terminal plates 3, 3 are provided with fixed core wires of connector-equipped electric wires 5, 5 that are electrically connected to a pair of electric wires X1, X2 extending from the solar cell module X. A male connector 5a and a female connector 5b are attached to the free end side of each connector-equipped electric wire 5, 5, which are the same type as the male connector X1a and the female connector X1b of the electric wires X1, X1, and are configured to mutually connect the male connector X1a and the female connector 5b, and the female connector X1b and the male connector 5a.

[0019] Furthermore, the pair of terminal boards 3, 3 are provided with fixed core wires of an input cable 6 and an output cable 7 that are electrically connected to other devices (the external terminal box 1 connected to the adjacent solar cell module X in the connection example shown in FIG. 5). Which cable is used as the input cable 6 and which is used as the output cable 7 is determined depending on the direction of current flow. In this embodiment, a male connector 6a is attached to the free end of the input cable 6, and a female connector 7a is attached to the free end of the output cable 7. The external terminal box 1 connected to the adjacent solar cell module X has a similar configuration, and the male connector 6a of the input cable 6 is connected to the female connector 7a of the output cable 7 extending from the adjacent external terminal box 1, and the male connector 6a of the input cable 6 extending from the adjacent external terminal box 1 on the opposite side is connected to the female connector 7a of the output cable 7. These male connectors 6a and female connectors 7a are also of the same type as the male connectors X1a and female connectors X1b of the electric wires X1, X1.

[0020] In order to extend these connector-equipped electric wires 5, 5, input cable 6 and output cable 7 from the box body 2, two grooves 2a (four in total) are formed on each side wall of the box body 2, and stoppers 21 are fitted into each of the grooves 2a to fix the connector-equipped electric wires 5, 5, input cable 6 and output cable 7 when inserted.

[0021] In this state, the inside of the box body 2 is filled with a resin molding material and solidified to form a molded section 8 (shown by hatching in Figs. 1 and 2) so as to be suitable for outdoor use. Furthermore, as shown in Figs. 4 and 5, a lid section 22 is fitted and fixed to the box body 2 so as to close the upward opening of the box body 2. Note that if it is possible to completely seal between the box body 2 and the lid section 22, and between the recessed groove 2a and the stopper 21, the connector-equipped electric wires 5, 5, the input cable 6, and the output cable 7, it is possible to omit the formation of the molded section 8 using a resin molding material.

[0022] 4 and 5, in the external terminal box 1 of this embodiment, the female connector 5b and the male connector 5a of the connector-attached electric wires 5, 5 are connected to the male connector X1a and the female connector X1b of the electric wires X1, X1 extending from the positive electrode and the negative electrode of the solar cell module X, respectively. This allows electricity generated in each cell in the solar cell module X to be sent to the external terminal box 1, which is outside the solar cell module X.

[0023] Furthermore, as shown in FIG. 5 , by connecting the male connector 6a of the input cable 6 to the female connector 7a of the output cable 7 extending from the external terminal box 1 connected to the adjacent solar cell module X, and connecting the male connector 6a of the input cable 6 extending from the external terminal box 1 connected to the opposite solar cell module X to the female connector 7a of the output cable 7, adjacent solar cell modules X can be connected in series via these external terminal boxes 1, and electricity can be sent to appropriate devices such as a power conditioner, a power distributor, a power storage device, and a power meter.

[0024] In the conventional solar cell module, electrical connection between the bus bar and the terminal box attached to the back side of the module was required, but in the next-generation solar cell module X, the bus bar is no longer used to connect the module and the external terminal box, and electric wires X1, X1 are used instead of the bus bar, so that the electrical connection between the solar cell module X and the external terminal box 1 can be completed by simply connecting the connectors X1a, X1b of the electric wires X1, X1 extending from the solar cell module X to the connectors 5a, 5b of the connector-attached electric wires 5, 5 of the external terminal box 1, simplifying the work process and significantly shortening the work time. In addition, since the connection work with the bus bar is no longer necessary, the inside of the box body 1 can be filled with a resin molding material in advance to form the molded part 5, and the external terminal box 1 can be sold in this state, so that the work process can be further simplified and the work time can be further shortened compared to the conventional work in which the molded part was formed after the connection with the bus bar.

[0025] In particular, even if the solar cell module X is a transparent or semi-transparent film type, attaching the terminal box 1 externally, i.e., providing the terminal box 1 outside the solar cell module X, does not impair the design of the solar cell module X and does not reduce the power generation efficiency, which is also useful for increasing the freedom of the installation location and shape of the solar cell module X.

[0026] The external terminal box of the present invention is not limited to the configuration of the above-mentioned embodiment. For example, the shape of the box body can be appropriately changed depending on the installation location and shape of the solar cell module. In addition, the free end of the connector-attached electric wire or input / output cable to which the male and female connectors are attached can be appropriately changed depending on the arrangement of the solar cell module, the specifications of the output side device, etc.

[0027] Furthermore, the specific configuration of each part is not limited to the above embodiment, and various modifications are possible without departing from the spirit of the present invention. [Industrial Applicability]

[0028] The external terminal box of the present invention is suitable for use as a terminal box provided on the outside of a module such as a perovskite solar cell, which is currently under development. [Explanation of symbols]

[0029] 1…External terminal box 2. Box body 3...Terminal board 4...Bypass diode 5…Connector-attached wire 6…Input cable 7…Output cable 8…Mold section X: Solar cell module X1…Electric wire

Claims

1. A terminal box for use in electrical connection to a solar cell module on the outside of the module, A box body is provided outside the solar cell module, An external terminal box for a solar cell module, characterized in that the box body is provided with a pair of terminal plates that are electrically connected to the electric wires extending from the positive and negative electrodes of the solar cell module and are electrically connected to each other, and input and output cables that are electrically connected to each terminal plate and extend outside the box body so as to be connectable to cables extending from other adjacent equipment.

2. The external terminal box for a solar cell module according to claim 1 , further comprising a bypass diode or a jumper wire for electrically connecting the pair of terminal plates.

3. a pair of connector-attached electric wires extending from the pair of terminal plates, respectively, and connectable to the electric wires extending from the positive electrode and the negative electrode, respectively; 3. The external terminal box for a solar cell module according to claim 1, wherein a connector is provided at each of the tip ends of the input cable and the output cable.

4. An external terminal box for a solar cell module as described in claim 3, further comprising a molded portion which is filled inside the box body and which is composed of a resin molding material that covers the pair of terminal boards, the pair of connector-equipped electric wires, the input cable, and the output cable inside the box body.

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