Improved high current terminal block

Abstract

The application discloses an improved large-current junction box and belongs to the field of photovoltaic junction box structure design. The technical scheme is characterized in that a bending groove is arranged on a terminal to limit and fix diode pins; a reserved soldering tin is used to form an electric connection with a diode; the reserved soldering tin flows into the bending groove, fixes the diode after cooling, and fully wraps the diode pins to increase heat dissipation capacity; the diode pins are located in the bending groove to fully dissipate heat to copper terminals and a bus bar; the bending groove also increases the total area of the copper terminals to improve heat dissipation capacity; a pin clamping mechanism and the reserved soldering tin are arranged on the terminal to limit and fix the diode after the diode is placed and to form an electric connection; a baffle is arranged on the terminal to prevent the tin in the bending groove from flowing out; and the bus bar is arranged on both sides of the diode through a hole to assist heat dissipation of the diode. The junction box is small in size, can bear large current, effectively enhances heat dissipation of the box body, reduces working temperature, and prolongs the service life of the photovoltaic junction box.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic junction box structure design, specifically relating to a high-current junction box, characterized by strong heat dissipation capacity and the ability to carry high current. Background Technology

[0002] A photovoltaic (PV) junction box is a connector that sits between the photovoltaic (PV) cell array and the battery charging control device. Its main function is to connect and protect the PV modules, enabling the electricity generated by the PV cells to be connected to external power lines and to conduct the electrical energy generated by the PV modules through cables. The PV junction box and the wiring system form a sealed space. The PV junction box provides protection against environmental impacts for the wires and their connections, and provides accessibility protection for live parts.

[0003] Due to the specific application scenarios and high cost of photovoltaic (PV) cells, PV junction boxes must be specially designed to meet the requirements of PV modules. A key technical indicator is the module's operating current. Operating current refers to the maximum forward current allowed to pass through a diode during continuous operation. Current flowing through a diode causes the diode's core to heat up, and exceeding the allowable temperature limit will cause overheating and damage. Therefore, the diode's rated forward operating current must not be exceeded. Current flows through the diode when the module experiences hot spot effects. Generally, a higher operating current is better, as it expands the operating range of the PV junction box. Simultaneously, to improve module power generation efficiency and reduce costs, the junction box's width and volume should be as small as possible. With technological advancements, the requirements for the current carrying capacity and miniaturization of solar PV junction boxes have become increasingly stringent, and the existing structure of PV junction boxes can no longer meet current usage requirements.

[0004] The applicant previously proposed a high-current photovoltaic junction box structure in Chinese patent CN202010393097.2. This structure enhances the junction box's heat dissipation capacity and achieves a larger bypass protection current by placing diodes sideways in the terminal structure and the busbar centrally located within it, while maintaining a small box width and volume. However, this solution still has room for improvement in terms of space utilization, simplified connection processes, diode placement and fixation, and optimized heat dissipation area. Summary of the Invention

[0005] The purpose of this invention is to provide an improved high-current junction box to solve the problems of mutual constraints in size, heat dissipation, and current carrying capacity of current photovoltaic junction boxes mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0007] An improved high-current junction box includes a base, within which a terminal structure is installed. The terminal structure includes a terminal and a diode soldered to the terminal. The base is filled with potting compound to cover the diode. The terminal is narrow and elongated, and has a curved groove extending in the width direction. The diode body is mounted on the terminal with its mounting position offset to one side of the terminal. The diode leads are bent, and the bent portions are placed in the curved groove. A pre-socketed solder joint is provided above the curved groove and the bent portions of the diode leads.

[0008] Furthermore, the terminal is welded to the busbar, and the busbar is mounted on the terminal at the center of the length and width directions of the terminal and on both sides of the diode body. The bending direction of the busbar during welding is consistent with the length direction of the terminal.

[0009] Furthermore, the terminal has busbar through holes on both sides of the diode body between the bent groove and the busbar. The busbar passes through the busbar through holes and is bent. The bent part of the busbar is soldered to the reserved solder.

[0010] Furthermore, the soldering area of ​​the busbar on the terminal and the soldering area of ​​the diode on the terminal are located on opposite sides of the reserved solder, respectively.

[0011] Furthermore, the terminal is provided with a pin-clamping mechanism, which is located on both sides of the diode body and engages with the non-bent portion of the diode pin.

[0012] Furthermore, the pin-clamping mechanism has pre-reserved solder for welding to the non-bent portion of the diode pin.

[0013] Furthermore, the terminal is provided with a baffle, which is located at the end of a curved groove on the side of the terminal opposite to the diode body.

[0014] Furthermore, the bottom of the groove is provided with pre-reserved solder so that the bent portion of the diode pin is soldered to the bottom of the groove.

[0015] Furthermore, the bottom of the curved groove is provided with a convex bulge or a groove, so that a gap is formed between the curved groove and the bent part of the diode pin for the pre-reserved solder to flow in after hot melting.

[0016] Due to the adoption of the above technical solution, the beneficial technical effects of the present invention are as follows:

[0017] This invention redesigns the terminal structure of a photovoltaic junction box, featuring strong heat dissipation capabilities and the ability to carry high currents. The invention utilizes pre-soldered solder for busbars and diodes, changing the traditional resistance welding connection method and simplifying the connection process. A curved groove structure provides restraint and fixation for the diode after placement, as well as ensuring electrical connection between the terminals and the diode. Pre-soldered solder flows into the curved groove during soldering, and after cooling, it fixes the diode and fully encloses the diode leads, increasing heat dissipation. The added bump further increases the solder inflow. The diode's position in the curved groove allows for efficient heat dissipation to the copper terminals and busbars. The curved groove also increases the total area of ​​the copper terminals, enhancing heat dissipation. A pin-clamping mechanism provides restraint and fixation for the diode after placement, as well as ensuring electrical connection between the terminals and the diode. A baffle prevents solder from flowing out of the curved groove. Perforations in the busbar are placed on both sides of the diode to aid in heat dissipation. In summary, this invention results in a more integrated junction box that effectively enhances heat dissipation, reduces operating temperature, and extends the lifespan of the photovoltaic junction box while carrying high currents.

[0018] The advantages of the present invention will be set forth in the following detailed description, and in some respects will become apparent from the description or may be learned by practice of the invention. Attached Figure Description

[0019] Figure 1 This is a perspective view of the high-current junction box of the present invention after the cover has been removed.

[0020] Figure 2 This is a top view of the high-current junction box of the present invention after the cover has been removed.

[0021] Figure 3 This is a front view of the terminal structure inside the high-current junction box of the present invention.

[0022] Figure 4 yes Figure 3 Front view of the terminal structure after removing the pre-reserved solder.

[0023] Figure 5 This is a back view of the terminal structure inside the high-current junction box of the invention.

[0024] The markings in the diagram are defined as follows: 1-base, 2-wire clip, 3-terminal, 4-diode, 41-diode body, 42-non-bent portion of diode pin, 43-bent portion of diode pin, 5-groove, 6-pin clipping mechanism, 7-baffle, 8-pre-reserved solder, 9-busbar through-hole. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] See Figure 1 and Figure 2 This embodiment uses a split-type junction box as an example for structural design. A split-type junction box refers to a single junction box that is divided into a positive terminal junction box, a negative terminal junction box, and several intermediate junction boxes. The purpose is to minimize the connection length and distribute the heat of the diode. In this embodiment, the junction boxes are the junction boxes at both ends of the split-type junction box. Obviously, the structural design of this invention is also applicable to single-type junction boxes.

[0027] See Figure 1 and Figure 2 The junction box of the present invention, viewed from the outside, includes a base 1 and a cover that snaps onto the top of the base 1. The base 1 and the cover together form the body of the junction box. The cover can adopt a conventional design in the art and is not shown in the figure, but this does not affect the understanding. The cover is removed to better show the terminal structure inside the junction box. In this embodiment, as the junction box at both ends of a split junction box, one end of the base 1 is provided with a wire clamp 2. The function of the wire clamp 2 is to allow the photovoltaic cable to pass through the middle of the wire clamp 2 and connect to the terminal structure inside the junction box. Obviously, if it were the junction box in the middle of the split junction box, there would be no wire clamp 2 structure.

[0028] See Figure 1 and Figure 2 The junction box contains a terminal structure, including terminals 3 and diodes 4. Terminals 3 consist of multiple pieces, each fitted onto a guide post inside the base 1 for fixation. Photovoltaic cables pass through the box and are soldered to terminals 3. Diodes 4 are soldered to terminals 3, electrically connecting the multiple terminals 3. The area below the diodes 4 is completely filled with potting compound. A busbar extends from the photovoltaic module, passes through the bottom of the junction box, and is soldered to terminals 3. The busbar is not shown in the diagram; its installation method is described below.

[0029] See Figures 3 to 5Terminal 3 is made of copper and consists of multiple pieces. Terminal 3 is narrow and long. Terminal 3 has two curved grooves 5 extending in the width direction of the terminal. Diode 4 consists of diode body 41 and diode pins. The diode pins are bent and divided into non-bent part 42 and bent part 43. As shown in the figure, the diode body 41 is installed on terminal 3 biased to one side of terminal 3. The bent part 43 of diode pins is placed in the two curved grooves 5. The curved grooves 5 and the bent part 43 of diode pins are provided with pre-reserved solder 8 above them. The functions of the above structure are as follows: the diode body 41 is offset to one side of the terminal 3, which reduces the width of the housing; the bending of the diode leads reduces the length of the housing, thus contributing to a smaller housing volume; the groove 5 provides a limiting and fixing effect for the diode 4 after placement; the pre-reserved solder 8 flows into the groove 5 during soldering, and after cooling, it fixes the diode leads and fully encloses them, increasing heat dissipation; the bent portion 43 of the diode leads is located in the groove 5, which can effectively dissipate heat to the terminal 3 and the busbar; the groove 5 is formed by bending the terminal 3, increasing the total area of ​​the terminal 3 and improving heat dissipation. The diode achieves electrical connection with the terminal through pre-reserved solder 8, changing the previous resistance soldering connection method between the diode and the terminal and simplifying the connection process; in addition, several bulges or grooves can be provided at the bottom of the groove 5 to form a gap between the groove and the bent portion of the diode leads, allowing the pre-reserved solder above to flow in after melting, improving the soldering quality; or a portion of pre-reserved solder can be directly provided at the bottom of the groove 5 to strengthen the soldering between the diode leads and the bottom of the groove, improving the soldering quality.

[0030] See Figures 3 to 5 Terminal 3 has two pin-clamping mechanisms 6 located on both sides of the diode body 41, which engage with the non-bent portion 42 of the diode pins. Terminal 3 also has two baffles 7 located at the ends of the grooves 5 on the opposite side of the diode body 41. The functions of this structure are: the pin-clamping mechanisms 6 can limit and fix the diode 4 after placement; some solder can be reserved at the pin-clamping mechanisms 6 to allow soldering between the pin-clamping mechanisms 6 and the non-bent portion 42 of the diode pins, improving the electrical connection between the diode and the terminal; the baffles 7 can prevent solder from flowing out of the grooves 5.

[0031] See Figures 3 to 5The busbar is positioned at the center of the length and width of terminal 3, and on both sides of diode body 41. The bending direction of the busbar during soldering is consistent with the length direction of terminal 3. Specifically, two busbar through-holes 9 are made on terminal 3 between the two bends 5 and the two sides of diode body 41. After the two busbars pass through the bottom of the housing, they pass through the busbar through-holes 9 and are then bent. The bent part of the busbar is soldered to the reserved solder 8. In this way, the soldering area of ​​the busbar on terminal 3 and the soldering area of ​​diode 4 on terminal 3 are located on opposite sides of the reserved solder 8. The functions of the above structure are as follows: the busbar through-hole 9 is located in the middle of the entire housing, so that the busbar installation position is also in the middle of the entire housing, which facilitates the heat dissipation of the busbar; the reserved solder 8 is used to solder the busbar, and the reserved solder is not limited to solder wire soldering or solder paste soldering; the busbar through-hole 9 is arranged on both sides of the diode, which can assist the diode in heat dissipation; the bent part 43 of the diode lead is located at the reserved solder 8 position, which can fully dissipate heat to the busbar that is also soldered at the reserved solder 8 position, which is beneficial to heat dissipation.

[0032] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An improved high-current junction box, comprising a base, a terminal structure mounted within the base, the terminal structure including terminals and diodes soldered to the terminals, the base being filled with potting compound to cover the diodes; characterized in that: The terminal is narrow and elongated, and a curved groove extending in the width direction of the terminal is provided on the terminal. The body of the diode is mounted on the terminal at a position biased towards one side of the terminal. The diode leads are bent and the bent portion is placed in the curved groove. A pre-reserved solder is provided above the curved groove and the bent portion of the diode leads.

2. The improved high-current junction box according to claim 1, characterized in that: The terminal is welded to the busbar. The busbar is installed on the terminal at the center of the length and width directions of the terminal and on both sides of the diode body. The bending direction of the busbar during welding is consistent with the length direction of the terminal.

3. An improved high-current junction box according to claim 2, characterized in that: The terminal has busbar through holes on both sides of the diode body between the bent groove and the busbar. The busbar passes through the busbar through holes and is bent. The bent part of the busbar is soldered to the reserved solder.

4. An improved high-current junction box according to claim 3, characterized in that: The soldering area of ​​the busbar on the terminal and the soldering area of ​​the diode on the terminal are located on opposite sides of the reserved solder, respectively.

5. An improved high-current junction box according to claim 1, characterized in that: The terminal is provided with a pin-clamping mechanism, which is located on both sides of the diode body and engages with the non-bent portion of the diode pin.

6. An improved high-current junction box according to claim 5, characterized in that: The pin-clamping mechanism has pre-reserved solder for welding to the non-bent portion of the diode pin.

7. An improved high-current junction box according to claim 1, characterized in that: The terminal is provided with a baffle, which is located at the end of a curved groove on the side of the terminal that is opposite to the diode body.

8. An improved high-current junction box according to claim 1, characterized in that: The bottom of the bend has a pre-reserved solder joint, which allows the bent portion of the diode pin to be soldered to the bottom of the bend.

9. An improved high-current junction box according to claim 1, characterized in that: The bottom of the bend is provided with a convex bulge or a groove, so that a gap is formed between the bend and the bent part of the diode pin for the pre-reserved solder to flow in after hot melting.

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