CN101789572A - Junction box for solar cell module - Google Patents

Abstract

A junction box for a solar cell module, comprising a box body, a heat dissipation unit, and at least two control circuits arranged in the box body that are not directly electrically connected to each other, the control circuit includes a diode and at least one electrical connection with the diode pin The conductor used to connect with the bus bar, the conductor and the diode are integrally formed. The invention also discloses the corresponding integrated structure of the diode and the heat sink, and the solar cell assembly with the junction box. The size and packaging of the diode are fundamentally changed by the invention, and the conductor in the junction box and the diode The pins are integrated, and the insulating and heat-conducting medium is integrated in the heat dissipation bottom of the diode, so that the heat dissipation effect is very good; in addition, the junction box of the present invention has good sealing performance, is convenient for system installation, and saves system cost.

Description

Junction box for solar cell module

technical field

The invention relates to the field of photovoltaics, in particular to a junction box for a solar battery module.

Background technique

In recent years, in the development of alternative energy sources, solar cell technology has made great breakthroughs, and its applications have become more and more extensive. Solar cell technology generally outputs electric energy through a photovoltaic system composed of solar cell components. The current solar cell module is generally composed of 54 to 72 solar cells in series. Inside the solar cell module, in order to protect the solar cell from being burned out when the hot spot effect occurs, it is usually the solar cells connected in series inside the solar cell module Divided into multiple branches, each branch is connected in parallel with a bypass diode for protection, for example, each branch connected in parallel with 18-24 solar cells is connected in parallel with a bypass diode, and multiple bypass diodes are set in one component In the junction box, it is installed on the conductive sheet or the terminal seat inside the box body. The junction box has lead-out cables, and then the junction boxes are connected to each other by cables and connectors to realize the connection between solar cell modules.

The disadvantage of such a junction box is: since the components all use a junction box, more cables are needed when the components are connected to each other, and because the box body of the junction box is separated from the connector of the cable, so when the system is installed It is necessary to fix the cables connected between the junction boxes to prevent the connection effect from being unstable due to the weight of the cables themselves and the connectors, which will reduce the efficiency of system installation; in addition, the bypass diode is enclosed in the junction box, and Since the inside of the junction box is in direct contact with the conductive sheet or terminal block installed by the bypass diode is a medium with poor thermal conductivity, so the heat generated by the bypass diode is difficult to dissipate, which will cause the temperature of the bypass diode to be too high. It will shorten the life of the bypass diode, or even make the bypass diode fail, and then cause the components to burn or reduce the quality. Moreover, the diodes of the junction box are connected to the conductors by welding, but the disadvantage is that the amount of conductors is relatively large, and a welding process is required.

In order to solve this problem, in the junction box of the prior art, a heat sink is generally added inside the junction box, but this will increase the size of the junction box, or the size of the heat dissipation structure is limited by the space in the junction box, and the heat cannot be dissipated quickly and effectively. The heat is transmitted to the outside of the junction box, so the heat dissipation effect is limited. Long-term use will also cause the problem of heat accumulation, which also increases the cost of the junction box.

In addition, in order to solve the above problems, there is a junction box with only one control circuit inside, that is, each junction box contains only one diode connected in parallel with the branch circuit, so it can only control one solar cell module or one solar cell module Therefore, when there are many branch circuits in a component, multiple junction boxes are required, which will also increase the cost of the component, and will waste a lot of cables and labor during the system installation process.

Contents of the invention

In order to solve the above problems, the present invention provides a junction box capable of simultaneously controlling several branches in a solar cell module, having good thermal conductivity, small size and cost saving.

To this end, the present invention provides a junction box for solar cell modules, which includes a box body, a heat dissipation unit, and at least two control circuits that are not directly electrically connected to each other arranged in the box body, and the control circuits include diodes and At least one conductor electrically connected to the pin of the diode and used for connecting to the bus bar, the conductor is integrally connected with the diode.

Preferably, the diode has a tube body and pins accommodated in the tube body, a part of the conductor penetrates into the diode tube body, and the pins of the diode and the pins of the conductor The part in the tube body of the diode is connected as one or integrally formed structure.

Preferably, partitions for preventing high-voltage arcs between diodes of the control circuits are provided between the control circuits.

Preferably, there is a spacer between the two pins of the diodes of each control circuit to prevent bus bars from overlapping.

Preferably, the heat dissipation unit includes a heat dissipation bottom plate arranged horizontally and a heat dissipation grid plate arranged vertically.

Preferably, the box is arranged on the periphery of the heat dissipation grid of the heat dissipation unit.

Preferably, the box body is arranged on the heat dissipation bottom plate of the heat dissipation unit, and the heat dissipation grid is arranged on the periphery of the box body.

Preferably, the box body and the heat dissipation unit are integrally formed.

Preferably, the conductor is a metal sheet.

Preferably, the tube body of the diode is configured as a rectangular parallelepiped.

Preferably, the diode includes a first pin and a second pin, the electrical conductor includes a first electrical conductor and a second electrical conductor, and the first pin and the first electrical conductor are integrally connected or integrally formed structure, the second pin and the second conductor are connected as one or integrally formed structure.

Preferably, the size of the first electrical conductor is larger than that of the second electrical conductor, and the first electrical conductor is provided with wiring holes for fixing connecting wires.

Preferably, the diode is connected to the heat dissipation unit through an insulating and heat-conducting medium.

Preferably, the insulating and heat-conducting medium is respectively bonded to the diode and the heat dissipation unit through heat dissipation glue.

Preferably, it is characterized in that a cable connector is provided on the box body, and the cable connector is electrically connected to the control circuit.

Preferably, the cable connector includes a male connector or a female connector.

Preferably, the junction box further includes a box cover, and the box cover is configured to only seal the area of the box body where the conductor is disposed.

Preferably, the junction box further includes a box cover, and the box cover is configured to only seal the area of the box body where the conductor is disposed.

Preferably, the box cover is fixedly connected to the box body through a bayonet structure.

Preferably, a sealing ring is provided between the box cover and the box body.

Preferably, the box cover or the box body has a sealing groove, and the sealing ring is arranged in the sealing groove.

The invention also discloses an integrated structure of a diode and a heat sink, including a diode and a heat sink. device connection.

Preferably, the heat sink includes a heat dissipation bottom plate arranged horizontally and a heat dissipation grid plate arranged vertically, and the diodes are connected to the heat dissipation bottom plate of the heat sink.

Preferably, the insulating and heat-conducting medium is heat-dissipating glue.

The invention also discloses a diode, which includes a tube body, a pin and a conductor electrically connected to the pin, and is characterized in that the diode pin and the conductor are integrally formed.

Preferably, the tube body of the diode is configured as a rectangular parallelepiped.

The present invention also discloses a solar cell assembly, which includes the above junction box for the solar cell assembly.

The invention also discloses a solar battery module, which includes the above-mentioned integrated structure of the diode and the radiator.

Through the solar cell module junction box of the present invention, the following beneficial effects can be achieved:

1. Fundamentally changed the size and packaging of the diode, made the conductor in the junction box and the pins of the diode integrally formed, and integrated the insulating and heat-conducting medium into the heat dissipation bottom of the diode;

2. The diode and the insulating heat dissipation medium part are combined with the radiator part through the heat dissipation glue, so that the two are more fit, the thermal resistance is small, which is good for heat dissipation, and fundamentally improves the heat dissipation capacity of the diode;

3. Injection-molding the parts integrating the diode, the insulating heat-conducting medium and the heat sink into the box body, which eliminates the damage to the diode during the assembly operation of the junction box, and because the components of the diode, the insulating heat-conducting medium and the heat sink The plastic fits well, which is more conducive to the heat dissipation of the diode through the plastic;

4. The heat sink of the box body is exposed to the air, and the function of the heat sink can be maximized by using air convection.

Description of drawings

Fig. 1 is an embodiment of the diode used for the junction box of the solar cell assembly provided by the present invention;

Fig. 2 is an embodiment of the integrated structure of the diode and radiator that the junction box for solar cell assembly provided by the present invention is used;

Fig. 3 is an embodiment of the solar cell assembly junction box provided by the present invention;

Fig. 4 is the schematic diagram of another embodiment of the solar cell assembly junction box provided by the present invention;

Fig. 5 is a schematic diagram after the junction box shown in Fig. 4 is covered with a lid;

Fig. 6 is the schematic view of another embodiment of the junction box for solar cell module provided by the present invention;

Fig. 7 is a schematic diagram after the junction box shown in Fig. 6 is covered with a cover;

Figure 8 is a schematic diagram of another embodiment of a junction box for a solar cell module provided by the present invention;

Fig. 9 is a schematic diagram after the junction box shown in Fig. 8 is covered with a cover;

Figure 10 is a schematic diagram of the circuit connection of the solar cell assembly provided by the present invention;

FIG. 11 is a schematic view of the solar cell assembly junction box provided by the present invention installed on the solar cell assembly shown in FIG. 10 .

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Fig. 1 is an embodiment of the diode used in the junction box for solar cell modules provided by the present invention, as shown in Fig. 1, the diode 3 has a tube body 31 and pins accommodated in the tube body 31, the first conductor 41, Second conductors 42 (such as metal sheets) are partially penetrated and arranged in the tube body 31 of diode 3, and the pins of diode 3 are integrally formed with first and second conductors 41, 42. The parts of the conductors 41, 42 outside the tube body 31 of the diode 3 can be used to connect bus bars, lead wires, etc. when the solar cell module is installed. Of course, the diode 2 can also be set so that only one pin is connected to one conductor. become one, and the other pin in the form of an ordinary diode pin. The preferred tube body 31 of the above-mentioned diode 3 is a cuboid, and is packaged with a material with excellent insulating properties; The feet are integrally formed, the size of the first conductor 41 is larger than that of the second conductor 42 , and the first conductor 41 is provided with a wiring hole 43 for fixing a bus bar or a lead wire.

In this implementation, the pins of the diode and the conductor are integrally formed, which greatly simplifies the connection between the diode and the conductor, and also simplifies the internal structure of the junction box where the diode is located, and does not require welding, which reduces the process and reduces the The cost is reduced; in addition, because the tube body of the diode is constructed as a cuboid, it is easy to be fixedly connected with other components.

Fig. 2 is an embodiment of the integrated structure of the diode and the radiator used in the solar cell module junction box provided by the present invention. In this embodiment, the diode shown in Fig. 1 is installed on the heat dissipation unit 2 to form the diode and the radiator integrated structure. As shown in Figure 2, the heat dissipation unit 2 includes a heat dissipation bottom plate 21 and a heat dissipation grid plate 22. The heat dissipation unit 2 is made of a material with good heat dissipation, such as a commonly used metal material. shown) is connected to the heat dissipation bottom plate 21 of the heat dissipation unit 2, for example, connected to the heat dissipation bottom plate 21 of the heat dissipation unit 2 through heat dissipation foam, mica sheet or heat dissipation silica gel. Preferably, the insulating and heat dissipation medium can be integrated at the bottom of the diode 3, for example, the heat dissipation bottom plate 21, the bottom of the diode 3 and the insulation and heat dissipation medium are combined together through heat dissipation glue, so that the combination of the heat dissipation unit 2, the insulation and heat dissipation medium and the diode 3 It is more compact, the thermal resistance is smaller, and it is more conducive to heat dissipation, thereby improving the heat dissipation capacity of the junction box, effectively preventing the bypass diode from being damaged due to excessive temperature, so as to ensure that the solar cell module will not be damaged due to excessive temperature.

In this implementation, the diode, the insulating heat dissipation medium, and the heat sink are bonded together by heat dissipation glue, so that the two are more closely bonded, the thermal resistance is small, and the heat dissipation is facilitated, which fundamentally improves the heat dissipation capacity of the diode.

Fig. 3 is a schematic diagram of an embodiment of a junction box for a solar cell module provided by the present invention. As shown in Figure 3, the junction box of this embodiment includes a box body 5, in which a heat dissipation unit 2 and at least two control circuits that are not directly electrically connected to each other are arranged in the box body 5, and each control circuit The circuit is used for parallel connection with the branch circuit in the solar battery module. Each control circuit includes a diode (not shown) and a conductor electrically connected to the diode pin for connecting with the bus bar. The conductor includes a first conductor 41, a second conductor 42, a first conductor, a second conductor The conductors 41, 42 and the diode are integrally formed. In the above-mentioned junction box, the diode (not shown), the insulating and heat-conducting medium and the heat dissipation unit 2 can be integrally injection-molded in the box body 5, which can eliminate the damage to the diode during the installation process of the junction box, thereby improving the reliability of the junction box. Reliability is also more conducive to the heat dissipation of the diode in the junction box; the heat dissipation unit 2 is closely connected with the box body 5 or is formed integrally with the box body 5 using different materials, such as integrally formed of metal and plastic. In this embodiment, the box body 5 is arranged on the periphery of the heat dissipation unit 2 . Preferably, partitions 51 are provided between the control circuits in the box body 5 to prevent high-voltage arcs from occurring between the diodes of the control circuits, thereby protecting the diodes. A bus bar can also be provided between the two pins of the diodes Overlapped partitions 53 .

The solar cell assembly junction box of this embodiment includes at least two control circuits, and each control circuit includes a bypass diode, so one junction box can protect at least two solar cell assembly branches connected in parallel with the bypass diodes. way, reducing the cost of the system. The bypass diode is connected to the heat dissipation part with good heat dissipation through the connection part made of a material with good insulation and thermal conductivity, and the heat dissipation part is closely connected or integrally formed with the box body, so the heat generated by the bypass diode can be dissipated safely and quickly , effectively prevent the bypass diode from being damaged due to high temperature, so as to ensure that the solar cell module will not be damaged due to high temperature; the diode and the insulating heat dissipation medium part are combined with the heat sink part through heat dissipation glue, making the two more efficient Bonding, small thermal resistance, good for heat dissipation, fundamentally improves the heat dissipation capacity of the diode, and injects the parts integrating the diode, insulating and heat-conducting medium and the heat sink into the box body, which eliminates the need for heat dissipation during the assembly operation of the junction box. Damage to the diode, in addition, because the diode, the insulating and heat-conducting medium and the parts of the radiator are well bonded to the heat dissipation glue, it is more conducive to the heat dissipation of the diode through the heat dissipation glue, and most of the heat dissipation unit is exposed to the air, and the air convection The function of the heat sink is maximized, and the heat dissipation capacity of the junction box is greatly improved.

Fig. 4 is a schematic diagram of another embodiment of the junction box for solar cell modules provided by the present invention; Fig. 5 is a schematic diagram of the junction box shown in Fig. 4 after the box cover is put on. As shown in Figures 4 and 5, the junction box 1 of this embodiment includes a box body 5, which is different from the junction box shown in Figure 3 in that the box body 5 is not arranged on the periphery of the heat dissipation unit 2, but is only arranged on the The central part of the unit 2, that is, the heat dissipation grid 22 of the heat dissipation unit 2 is arranged on the periphery of the box body 5, so that the heat dissipation unit 2 is more exposed to the air, and the heat dissipation of the junction box 1 is further improved. Preferably, partitions 51 are provided between the control circuits in the box body 5 to prevent high-voltage arcs from occurring between the diodes of the control circuits, thereby protecting the diodes. A bus bar can also be provided between the two pins of the diodes Overlapped separators (not shown).

As shown in Fig. 5, the above-mentioned junction box may further include a box cover 52, and the box cover 52 is configured to only seal the area where the conductor is arranged in the box body 5, that is, to expose the heat dissipation unit 2 to the air as much as possible. , in order to facilitate the heat dissipation of the junction box. The heat dissipation grid plate 22 and/or part of the heat dissipation bottom plate 21 of the heat dissipation unit 2 can be exposed to the air, which is more conducive to the heat dissipation of the diode in the junction box, and the box cover 52 can also be used for marking graphics and text symbols, etc.; A sealing ring (not shown) for increasing the sealing performance of the junction box 1 can be provided between the box body 5 and the box cover 52, and can be placed in a sealing ring groove (not shown) on the box body 5 or the box cover 52 ; The box body 5 and the box cover 52 can be sealed and connected by a known connection method such as a buckle structure (not shown), and the box body 5 and the heat dissipation unit 2 can also be integrally formed.

Fig. 6 is the schematic diagram of another embodiment of the junction box for solar cell assembly provided by the present invention; Fig. 7 is the schematic diagram after the junction box shown in Fig. 6 is covered with a box cover, as shown in Fig. 6 and Fig. Among them, the junction box 1' is similar to the above junction box 1, and in each control circuit, only one conductor is electrically connected to the pin of a diode (not shown) as a whole or integrally formed. The box body 5 of the junction box 1' is provided with a cable connector, and the cable connector includes a cable 74, a nut 73 and a male head (plug), wherein the male head is connected to the cable wire 74 according to common knowledge in the art. The cable connector is arranged on the box body 5 through the nut 73 and is electrically connected with a control circuit in the box body 5, that is, the male head is electrically connected with the first conductor and the second conductor in the junction box respectively, In an optional embodiment of the present invention, the cable connector may also be connected to the box body 5 in other ways. Preferably, partitions 51 are provided between the control circuits in the box body 5 to prevent high-voltage arcs from occurring between the diodes of the control circuits, thereby protecting the diodes. A bus bar can also be provided between the two pins of the diodes Overlapped separators (not shown).

Fig. 8 is a schematic diagram of another embodiment of a junction box for solar cell modules provided by the present invention; Fig. 9 is a schematic diagram after the junction box shown in Fig. 8 is covered with a cover, as shown in Fig. 8 and Fig. 9, the present embodiment Among them, the solar cell assembly junction box 1″ is similar to the junction box 1 above, and the box body 5 of the junction box 1″ is provided with a cable connector including a male head 71 and a female head 72, and the cable connector is connected to the box body 5. A control circuit is electrically connected. Preferably, partitions 51 are provided between the control circuits in the box body 5 to prevent high-voltage arcs from occurring between the diodes of the control circuits, thereby protecting the diodes. A bus bar can also be provided between the two pins of the diodes Overlapped separators (not shown).

The junction box 1' shown in Figure 6 and Figure 7 and the junction box 1" shown in Figure 8 and Figure 9 can be electrically connected to each other through the male and female connectors included in the cable connector. The method is simple and not only can save a lot of cables. Connecting wires, the connection between junction boxes is more reliable and convenient, especially can improve system installation efficiency. And junction box 1 shown in Fig. 4, Fig. 5 and junction box 1 ' shown in Fig. 6, Fig. 7 and Fig. 8, The junction boxes 1 ″ shown in FIG. 9 can be electrically connected using the bus bars in the solar cell modules.

FIG. 10 is a schematic diagram of a circuit connection of a solar cell module of the present invention, and FIG. 11 is a schematic diagram of a junction box for a solar cell module of the present invention installed on the solar cell module shown in FIG. 10 . As shown in Fig. 10 and Fig. 11, the solar cell assembly 6 of this embodiment is equipped with the above-mentioned junction box, and the junction box is installed in the middle of the solar cell assembly 6, since the illustrated solar cell assembly 6 is divided into six branches road, and each junction box shown in the figure includes two control circuits 2, so three junction boxes are provided on the solar cell assembly 6, but this is only an example, and is not intended to limit the present invention. The two control circuits in each junction box are respectively opposite to the position of the solar cell assembly 6 and the two branches that are not directly electrically connected to each other are connected in parallel through the bus bar 61. The three junction boxes are preferably junction boxes 1, 1' respectively. . When the solar cell modules of 1" are electrically connected, the junction boxes that are preferably connected to each other by two solar cell modules 6 in adjacent positions are respectively junction boxes 1' and 1", so that junction boxes 1' and The 1" cable connector quickly and reliably connects a plurality of solar cell modules 6 together, which can save connecting cables and because the cable used is relatively short and the cable connector and the junction box are integrated without connecting the cables. fixed, thus improving system installation efficiency and reducing system cost.

In a word, the above descriptions are only examples of the present invention, not for limiting the protection scope of the present invention, but for illustrating the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (28)

1. junction box for solar cell module, comprise box body, heat-sink unit and be arranged in the described box body at least two and not have the directly control circuits of electric connection mutually, described control circuit comprises that diode and at least one and diode pin be electrically connected is used for the electric conductor that is connected with busbar, it is characterized in that described electric conductor and diode connect as one.

2. terminal box as claimed in claim 1, it is characterized in that, described diode has body and is contained in the interior pin of described body, the part of described electric conductor penetrates and is arranged in the described diode body, and the part structure that connects as one or be formed in one in the body that is in described diode of the pin of described diode and described electric conductor.

3. terminal box as claimed in claim 1 is characterized in that, is provided with the dividing plate that produces high-voltage arc between the diode that is used to prevent each control circuit between each control circuit.

4. as claim 1 or 3 described terminal boxes, it is characterized in that having the dividing plate that prevents the busbar overlap joint between two pins of the diode of described each control circuit.

5. terminal box as claimed in claim 1 is characterized in that, described heat-sink unit comprises horizontally disposed radiating bottom plate and the heat radiation screen that vertically is provided with.

6. terminal box as claimed in claim 5 is characterized in that, described box body is arranged on the periphery of the heat radiation screen of described heat-sink unit.

7. terminal box as claimed in claim 5 is characterized in that described box body is arranged on the radiating bottom plate of described heat-sink unit, and described heat radiation screen is arranged on the periphery of described box body.

8. terminal box as claimed in claim 5 is characterized in that, described box body and the heat-sink unit structure that is formed in one.

9. terminal box as claimed in claim 1 is characterized in that, described electric conductor is a sheet metal.

10. terminal box as claimed in claim 1 is characterized in that, the structure of tube body of described diode is a cuboid.

11. terminal box as claimed in claim 1, it is characterized in that, described diode comprises first pin and second pin, described electric conductor comprises first electric conductor and second electric conductor, described first pin and first electric conductor structure that connects as one or be formed in one, described second pin and second electric conductor structure that connects as one or be formed in one.

12. terminal box as claimed in claim 11 is characterized in that, the size of described first electric conductor is greater than the size of described second electric conductor, and described first electric conductor is provided with the wiring hole that is used for fixing connecting line.

13. terminal box as claimed in claim 1 is characterized in that, described diode is connected with described heat-sink unit by insulated heat-conducting medium.

14. terminal box as claimed in claim 13 is characterized in that, described insulated heat-conducting medium is bonding with described diode and heat-sink unit respectively by thermal paste.

15., it is characterized in that it is characterized in that described box body is provided with cable connectors, described cable connectors is electrically connected with described control circuit as claim 1,3,5,11 each described terminal boxes.

16. terminal box as claimed in claim 15 is characterized in that, described cable connectors comprises male or female.

17. terminal box as claimed in claim 1 is characterized in that, described terminal box also comprises lid, and described lid is configured to only seal the zone that is provided with described electric conductor in the described box body.

18. terminal box as claimed in claim 15 is characterized in that, described terminal box also comprises lid, and described lid is configured to only seal the zone that is provided with described electric conductor in the described box body.

19. terminal box as claimed in claim 17 is characterized in that, described lid is fixedlyed connected by bayonet arrangement with box body.

20. terminal box as claimed in claim 19 is characterized in that, has sealing ring between lid and the box body.

21. terminal box as claimed in claim 20 is characterized in that, has seal groove on described lid or the box body, described sealing ring is arranged in the described seal groove.

22. the integrated morphology of diode and radiator comprises diode and radiator, it is characterized in that be wholely set the electric conductor that is electrically connected with pin on the described diode, described diode is connected with radiator by insulated heat-conducting medium.

23. integrated morphology according to claim 22 is characterized in that, described radiator comprises horizontally disposed radiating bottom plate and the heat radiation screen that vertically is provided with, and described diode is connected on the radiating bottom plate of radiator.

24. integrated morphology according to claim 22 is characterized in that, described insulated heat-conducting medium is a thermal paste.

25. a diode, comprise body, pin and with the electric conductor that pin is electrically connected, it is characterized in that described diode pin and the described electric conductor structure that is formed in one.

26. diode according to claim 25 is characterized in that, the structure of tube body of described diode is a cuboid.

27. a solar module is characterized in that, comprises as claim 1 each described junction box for solar cell module to the claim 21.

28. a solar module comprises junction box for solar cell module, it is characterized in that, described terminal box comprises the integrated morphology as claim 22 each described diode and radiator to the claim 24.

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