Photovoltaic junction box capable of automatic shutdown

Abstract

The application relates to an automatically closed photovoltaic junction box, and relates to the technical field of photovoltaic junction boxes, which comprises a junction box assembly, a connecting assembly, a conductive row, a control module, a state detection module and a switch execution module. The voltage detection unit and the current detection unit of the state detection module are used for double monitoring of the voltage and current states of the photovoltaic assembly, so that misjudgment caused by single detection is avoided; after detection signals are transmitted to the control module in real time, the control module can quickly drive the MOS tube group of the switch execution module to act, and the conductive row is used for realizing short-circuit protection of the shaded cell piece and recovery of power generation after the hot spot disappears, without manual intervention, so that the problems of response lag and high maintenance cost of the traditional junction box are effectively solved; the shell, the dust cover and the silica gel sealing ring of the junction box assembly can isolate external dust and rainwater, and the first clamping groove, the second clamping groove and the third clamping groove can regulate the installation layout of the conductive row, the control module and the state detection module.

Description

Technical Field

[0001] This application relates to the field of photovoltaic junction box technology, and in particular to a photovoltaic junction box that can be automatically shut off. Background Technology

[0002] When a photovoltaic module is working, if some of the cells are shaded, such as by dust, leaves, or shadows, the shaded cells will turn from power generation units into load units, generating a hot spot effect. Not only will they be unable to generate electricity themselves, but they will also consume the electrical energy of other normal cells, causing local temperature rise. This will affect the overall power generation efficiency of the photovoltaic module and may damage the cells in the long run.

[0003] Traditional photovoltaic junction boxes only have a current collection function and cannot identify the voltage and current status of the solar cells. They also cannot actively intervene in the hot spot effect and require manual inspection of obstructions. This results in problems such as slow response, high maintenance costs, and continuous power generation loss. Therefore, there is an urgent need for a photovoltaic junction box that is simple in structure, low in cost, and can automatically identify hot spots and realize shutdown and recovery to solve the above defects. Utility Model Content

[0004] The purpose of this application is to provide a photovoltaic junction box that can be automatically shut off, which has the advantage of automatic shutdown and solves the problems mentioned in the background art.

[0005] This application provides an automatically shut-off photovoltaic junction box, employing the following technical solution: An automatically shut-off photovoltaic junction box includes a junction box assembly, a connecting assembly, a conductive busbar, a control module, a status detection module, and a switch execution module. The connecting assembly includes input terminals and output terminals, which are respectively located on both sides of the junction box assembly. The conductive busbar is located inside the junction box assembly, with its two ends connected to the input terminals and output terminals, respectively. The status detection module is connected to the input terminals and is used to detect the operating status of the photovoltaic module. The control module is electrically connected to both the status detection module and the switch execution module, and is used to receive the detection signal from the status detection module and control the operation of the switch execution module. The switch execution module is connected in parallel with the conductive busbar to realize the on / off control of the photovoltaic module.

[0006] By adopting the above technical solution, the working status of photovoltaic modules can be monitored in real time through the status detection module. When an abnormal state caused by hot spot effect is detected, the control module can quickly receive the signal and control the switch execution module to act. The switch execution module works with the busbar to achieve short circuit protection for the shaded cells, preventing the shaded cells from consuming the power of other normal cells. No manual inspection or intervention is required. This effectively solves the problems of slow response, high maintenance costs, and continuous power generation loss of traditional photovoltaic junction boxes, while ensuring the overall power generation efficiency of photovoltaic modules and reducing the risk of module damage.

[0007] Preferably, the junction box assembly includes a housing, a first slot, a second slot, and a third slot, all of which are disposed inside the housing.

[0008] By adopting the above technical solution, the housing can protect the internal modules and prevent external environmental factors from affecting the operation of the components. At the same time, the first, second and third slots can provide the installation and positioning foundation for subsequent functional components, making the layout of each component in the housing more regular and preventing the components from shifting due to vibration and other factors. This solves the problem of easy loosening and chaotic layout of internal components in traditional junction boxes and improves the overall structural stability of the junction box.

[0009] Preferably, the conductive busbar is installed inside the first slot, the control module is installed inside the second slot, and the status detection module is installed inside the third slot.

[0010] By adopting the above technical solution, the conductive busbar, control module, and status detection module are respectively installed in the first slot, second slot, and third slot. The installation position of each component can be clearly defined, which not only facilitates rapid positioning during production assembly and reduces assembly difficulty, but also shortens the connection distance between modules, reduces interference during signal transmission, and ensures the accuracy of the control module receiving signals from the status detection module. At the same time, it is convenient to quickly find the corresponding components during subsequent maintenance, solving the problems of low assembly efficiency, inconvenient maintenance, and susceptibility to signal interference in traditional junction boxes.

[0011] Preferably, a first thermally conductive silicone pad is fixedly connected to the bottom surface of the housing, a dust cover is provided on the top of the housing, and a silicone sealing ring is fixedly connected to the bottom surface of the dust cover.

[0012] By adopting the above technical solutions, the first thermally conductive silicone pad can assist the heat dissipation of the internal heat-generating components of the housing, preventing the components from degrading or being damaged due to long-term high-temperature operation; the dust cover can prevent external dust from entering the housing, and the silicone sealing ring can enhance the sealing between the dust cover and the housing, isolating rainwater, moisture, etc., effectively solving the problems of insufficient protection of traditional junction boxes, easy corrosion of internal components by dust and rainwater or overheating damage, and extending the service life of the junction box.

[0013] Preferably, connecting bolts are installed at all four corners of the dust cover, and the dust cover is fixedly connected to the housing by the connecting bolts.

[0014] By adopting the above technical solution, the connecting bolts can firmly fix the dust cover to the top of the housing, preventing the dust cover from falling off due to external force and ensuring the protective effect. At the same time, the dust cover can be opened by unscrewing the connecting bolts, which facilitates the inspection or maintenance of the internal components of the housing. This solves the problems of inconvenient disassembly and assembly and low maintenance efficiency of the traditional junction box dustproof structure, and improves the convenience of subsequent maintenance.

[0015] Preferably, the status detection module includes a voltage detection unit and a current detection unit. The voltage detection unit is connected in parallel across the two ends of the input terminal, and the current detection unit is connected in series in the busbar. Both are electrically connected to the control module.

[0016] By adopting the above technical solution, the voltage detection unit can monitor the voltage status of the photovoltaic module in real time, and the current detection unit can monitor the current status of the photovoltaic module in real time. The two work together to achieve dual detection of the working status of the photovoltaic module, avoiding misjudgment caused by a single detection method and ensuring accurate identification of abnormalities when hot spot effect occurs. At the same time, the detection signal can be transmitted to the control module in a timely manner, providing a reliable basis for the subsequent control actions of the control module, solving the problem that traditional junction boxes cannot identify the voltage and current status of the cells, and improving the accuracy and reliability of hot spot identification.

[0017] Preferably, the switch execution module includes a second thermally conductive silicone pad, a MOSFET group, and a reverse diode. The MOSFET group is attached to the inner wall of the housing via the second thermally conductive silicone pad. The reverse diode is connected in parallel with the MOSFET group, and the control terminal of the MOSFET group is connected to the control module.

[0018] By adopting the above technical solutions, the MOSFET group can quickly respond to the commands of the control module to realize the on-off control of the photovoltaic module, thereby completing short-circuit protection under hot spot conditions and power generation recovery after the hot spot disappears; the second thermally conductive silicone pad can assist the MOSFET group in heat dissipation, avoiding the MOSFET group from being affected by heat generation; the reverse diode can prevent reverse voltage from breaking down the MOSFET group, protecting the MOSFET group from damage, solving the problem that traditional junction boxes cannot actively intervene in the hot spot effect and the execution components are easily damaged, improving the working stability and service life of the switching execution module.

[0019] Preferably, positioning bases are fixedly connected to the four corners of the bottom of the housing.

[0020] By adopting the above technical solution, the positioning base can be precisely matched with the installation position of the photovoltaic module during the installation of the junction box assembly, so that the junction box is stably fixed on the photovoltaic module. This avoids displacement of the junction box due to vibration, external force or other factors after installation, which would cause the input terminals, output terminals and external lines to become loose and affect current transmission.

[0021] In summary, this application includes at least one of the following beneficial technical effects: This type of photovoltaic junction box with automatic shutdown function uses a voltage detection unit and a current detection unit in the status detection module to dual monitor the voltage and current status of the photovoltaic module, avoiding misjudgments caused by single detection. After the detection signal is transmitted to the control module in real time, the control module can quickly drive the MOSFET group of the switching execution module to operate. In conjunction with the conductive busbar, it realizes short circuit protection for the shaded cells and restoration of power generation after the hot spots disappear. No manual intervention is required, effectively solving the problems of slow response and high maintenance costs of traditional junction boxes. The housing, dust cover and silicone sealing ring of the junction box assembly can isolate external dust and rainwater. The first, second and third slots can organize the installation layout of the conductive busbar, control module and status detection module, improving structural stability. The first and second thermally conductive silicone pads assist in heat dissipation of the internal components, and the reverse diode protects the MOSFET group from reverse voltage damage. Overall, it not only ensures the power generation efficiency of the photovoltaic module, but also extends the service life of the junction box, solving the defects of insufficient protection and easy damage of traditional junction boxes. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall front view structure of this application; Figure 2 This is a schematic diagram of the overall top view of the structure of this application; Figure 3 This is a schematic diagram of the overall sectional planar structure of this application; Figure 4 This is a partial top view of the structural plan of this application; Figure 5 This is a partial top view of the structure of this application.

[0023] In the picture: 1. Junction box assembly; 101. Housing; 102. First slot; 103. Second slot; 104. Third slot; 105. First thermally conductive silicone pad; 106. Dust cover; 107. Silicone sealing ring; 108. Connecting bolt; 2. Connecting assembly; 201. Input terminal; 202. Output terminal; 3. Conductive busbar; 4. Control module; 5. Status detection module; 501. Voltage detection unit; 502. Current detection unit; 6. Switch execution module; 601. Second thermally conductive silicone pad; 602. MOSFET group; 603. Reverse diode; 7. Positioning base. Detailed Implementation

[0024] The following is in conjunction with the appendix Figure 1 - Appendix Figure 5 This application will be described in further detail below.

[0025] Example 1: A photovoltaic junction box with automatic shutdown capability, referring to... Figure 1 , Figure 3 and Figure 4The system includes a junction box assembly 1, a connection assembly 2, a conductive busbar 3, a control module 4, a status detection module 5, and a switch execution module 6. The connection assembly 2 includes an input terminal 201 and an output terminal 202, which are respectively located on both sides of the junction box assembly 1. The conductive busbar 3 is located inside the junction box assembly 1, with its two ends connected to the input terminal 201 and the output terminal 202, respectively. The status detection module 5 is connected to the input terminal 201 and is used to detect the operating status of the photovoltaic module. The control module 4 is electrically connected to both the status detection module 5 and the switch execution module 6, and is used to receive signals from the status detection module. The detection signal from block 5 controls the operation of switch execution module 6. Switch execution module 6 is connected in parallel with busbar 3 to realize the on / off control of photovoltaic module. Status detection module 5 includes voltage detection unit 501 and current detection unit 502. Voltage detection unit 501 is connected in parallel across input terminal 201, and current detection unit 502 is connected in series in busbar 3. Both are electrically connected to control module 4. Voltage detection unit 501 can monitor the voltage status of photovoltaic module in real time, and current detection unit 502 can monitor the current status of photovoltaic module in real time. The two work together to achieve dual detection of photovoltaic module operating status, avoiding single detection. To prevent misjudgments caused by the detection method, this module ensures accurate identification of anomalies when hot spot effects occur. Simultaneously, the detection signal can be promptly transmitted to the control module 4, providing a reliable basis for subsequent control actions. This solves the problem of traditional junction boxes being unable to identify the voltage and current status of battery cells, improving the accuracy and reliability of hot spot identification. The switch execution module 6 includes a second thermally conductive silicone pad 601, a MOSFET group 602, and a reverse diode 603. The MOSFET group 602 is attached to the inner wall of the housing 101 via the second thermally conductive silicone pad 601. The reverse diode 603 is connected in parallel with the MOSFET group 602, and the control of the MOSFET group 602... The control terminal is connected to the control module 4. The MOSFET group 602 can quickly respond to the commands of the control module 4 to realize the on-off control of the photovoltaic module, thereby completing the short-circuit protection under hot spot conditions and the restoration of power generation after the hot spot disappears. The second thermally conductive silicone pad 601 can assist the MOSFET group 602 in heat dissipation and prevent the MOSFET group 602 from being affected by heat. The reverse diode 603 can prevent the reverse voltage from breaking down the MOSFET group 602 and protect the MOSFET group 602 from damage. This solves the problem that traditional junction boxes cannot actively intervene in the hot spot effect and the execution components are easily damaged, thus improving the working stability and service life of the switching execution module 6.

[0026] Reference Figure 3 , Figure 4 and Figure 5The junction box assembly 1 includes a housing 101, a first slot 102, a second slot 103, and a third slot 104. The first slot 102, second slot 103, and third slot 104 are all located inside the housing 101. The housing 101 provides protection for the internal modules, preventing external environmental factors from affecting the component's operation. Simultaneously, the first slot 102, second slot 103, and third slot 104 provide a mounting base for subsequent functional components, resulting in a more orderly layout of components within the housing 101 and preventing component displacement due to vibration or other factors. This solves the problems of loose components and chaotic layout in traditional junction boxes, improving the overall structural stability of the junction box. The conductive busbar 3 is installed in the first slot. Inside slot 102, control module 4 is installed in the second slot 103, and status detection module 5 is installed in the third slot 104. By installing conductive busbar 3, control module 4, and status detection module 5 in the first slot 102, second slot 103, and third slot 104 respectively, the installation position of each component can be clearly defined. This not only facilitates quick positioning during production assembly and reduces assembly difficulty, but also shortens the wiring distance between modules, reduces interference during signal transmission, and ensures the accuracy of the control module 4 receiving signals from status detection module 5. At the same time, it facilitates quick location of the corresponding components during subsequent maintenance, solving the problems of low assembly efficiency, inconvenient maintenance, and susceptibility to signal interference in traditional junction boxes.

[0027] Example 2: A photovoltaic junction box with automatic shutdown capability, refer to Figure 2 , Figure 3 and Figure 5Based on the same concept as Embodiment 1 above, this embodiment proposes that a first thermally conductive silicone pad 105 is fixedly connected to the bottom surface of the housing 101, and a dust cover 106 is provided on the top of the housing 101. A silicone sealing ring 107 is fixedly connected to the bottom surface of the dust cover 106. The first thermally conductive silicone pad 105 can assist in the heat dissipation of the internal heat-generating components of the housing 101, preventing the components from degrading or being damaged due to long-term high-temperature operation. The dust cover 106 can prevent external dust from entering the interior of the housing 101, and the silicone sealing ring 107 can enhance the sealing between the dust cover 106 and the housing 101, isolating rainwater, moisture, etc., effectively solving the problems of insufficient protection of traditional junction boxes, easy corrosion of internal components by dust and rainwater or overheating damage, and extending the service life of the junction box. Connecting bolts 108 are installed at the four corners of the dust cover 106. The dust cover 106 is fixedly connected to the housing 101 by connecting bolts 108. The connecting bolts 108 can firmly fix the dust cover 106 to the top of the housing 101, preventing the dust cover 106 from falling off due to external force and ensuring the protective effect. At the same time, the dust cover 106 can be opened by unscrewing the connecting bolts 108, which facilitates the inspection or maintenance of the internal components of the housing 101. This solves the problems of inconvenient disassembly and assembly and low maintenance efficiency of traditional junction box dustproof structures, and improves the convenience of subsequent maintenance. Positioning bases 7 are fixedly connected to the four corners of the bottom of the housing 101. The positioning bases 7 can accurately match the installation position of the photovoltaic module when the junction box assembly 1 is installed, so that the junction box is stably fixed on the photovoltaic module. This prevents the junction box from shifting due to vibration, external force and other factors after installation, which would cause the input terminal 201, output terminal 202 and external line connection to loosen and affect current transmission.

[0028] The implementation principle of this application embodiment is as follows: First, the junction box assembly 1 is stably fixed in the corresponding position of the photovoltaic module by the positioning base 7. The input terminal 201 of the connecting assembly 2 is electrically connected to the solar cell of the photovoltaic module, and the output terminal 202 is connected to the external combiner box. The conductive bus 3 is installed in the first slot 102 inside the housing 101, with its two ends respectively connected to the input terminal 201 and the output terminal 202 to form the initial current transmission channel. At this time, the control module 4 is installed in the second slot 103, and the status detection module 5 is fixed in the third slot 104. Its voltage detection unit 501 is connected in parallel to both ends of the input terminal 201 to collect the solar cell voltage signal in real time, and the current detection unit 502 is connected in series in the conductive bus 3 to synchronously acquire the current signal. Both transmit the detection signal to the control module 4. When the photovoltaic module is unshaded and in normal power generation mode, the signals detected by the voltage detection unit 501 and the current detection unit 502 are both within the normal range. Based on this, the control module 4 outputs a control signal to keep the MOSFET group 602 of the switching execution module 6 in the off state. The current generated by the photovoltaic module cells is then transmitted along the busbar 3 through the input terminal 201, the busbar 3, and the output terminal 202 to the combiner box, achieving normal power generation. When the photovoltaic module is partially shaded, causing a hot spot effect, the voltage and current of the shaded cells will drop rapidly. The voltage detection unit 501 and the current detection unit 502 immediately capture this abnormal signal and transmit it to the control module 4. The control module 4 quickly analyzes the signal and switches the output signal, driving the MOSFET group 602 to conduct. At this time, the MOSFET group 602 is attached to the inner wall of the housing 101 for heat dissipation through the second thermally conductive silicone pad 601. The parallel reverse diode 603 prevents the reverse voltage from breaking down the MOSFET group 602. The shaded cells then conduct electricity. A short circuit is formed by the conducting MOSFET group 602, allowing current to bypass the blocked solar cell and continue to be transmitted through other normal solar cells and the busbar 3, avoiding power loss and component damage caused by hot spots. When the obstruction is removed and the hot spot disappears, the voltage and current signals detected by the voltage detection unit 501 and the current detection unit 502 return to normal. This recovery signal is transmitted to the control module 4. The control module 4 performs a short delay to avoid misjudgment due to signal fluctuations, and then outputs a signal to turn off the MOSFET group 602 again. The short-circuited solar cell is reconnected to the current transmission channel where the busbar 3 is located, and normal power generation is restored. Throughout the process, the housing 101, dust cover 106, and silicone sealing ring 107 work together to isolate external dust and rainwater, ensuring stable operation of internal components. The connecting bolt 108 ensures a firm connection between the dust cover 106 and the housing 101. The first thermally conductive silicone pad 105 assists in heat dissipation of other heat-generating components inside the housing 101, realizing fully automatic hot spot identification, protection, and power generation recovery.

Claims

1. An automatically shut-off photovoltaic junction box, comprising a junction box assembly (1), a connecting assembly (2), a conductive row (3), a control module (4), a state detection module (5) and a switch execution module (6), characterized in that: The connection component (2) includes an input terminal (201) and an output terminal (202). The input terminal (201) and the output terminal (202) are respectively located on both sides of the junction box component (1). The conductive bus (3) is located inside the junction box component (1), and its two ends are respectively connected to the input terminal (201) and the output terminal (202). The status detection module (5) is connected to the input terminal (201) and is used to detect the working status of the photovoltaic module. The control module (4) is electrically connected to the status detection module (5) and the switch execution module (6) respectively, and is used to receive the detection signal from the status detection module (5) and control the action of the switch execution module (6). The switch execution module (6) is connected in parallel with the conductive bus (3) and is used to realize the on / off control of the photovoltaic module.

2. A self-closing photovoltaic junction box according to claim 1, characterized in that: The junction box assembly (1) includes a housing (101), a first slot (102), a second slot (103) and a third slot (104), wherein the first slot (102), the second slot (103) and the third slot (104) are all disposed inside the housing (101).

3. The photovoltaic junction box with automatic shut-off according to claim 2, characterized in that: The conductive bus (3) is installed inside the first slot (102), the control module (4) is installed inside the second slot (103), and the status detection module (5) is installed inside the third slot (104).

4. The photovoltaic junction box with automatic shut-off according to claim 2, characterized in that: The bottom surface of the housing (101) is fixedly connected to a first thermally conductive silicone pad (105), and the top of the housing (101) is provided with a dust cover (106), and the bottom surface of the dust cover (106) is fixedly connected to a silicone sealing ring (107).

5. A photovoltaic junction box with automatic shut-off according to claim 4, characterized in that: The dust cover (106) is equipped with connecting bolts (108) at each of its four corners, and the dust cover (106) is fixedly connected to the housing (101) by the connecting bolts (108).

6. The photovoltaic junction box with automatic shut-off according to claim 1, characterized in that: The status detection module (5) includes a voltage detection unit (501) and a current detection unit (502). The voltage detection unit (501) is connected in parallel to both ends of the input terminal (201), and the current detection unit (502) is connected in series in the busbar (3). Both are electrically connected to the control module (4).

7. A photovoltaic junction box with automatic shut-off capability according to claim 1, characterized in that: The switch execution module (6) includes a second thermally conductive silicone pad (601), a MOS transistor group (602), and a reverse diode (603). The MOS transistor group (602) is attached to the inner wall of the housing (101) through the second thermally conductive silicone pad (601). The reverse diode (603) is connected in parallel with the MOS transistor group (602), and the control terminal of the MOS transistor group (602) is connected to the control module (4).

8. A photovoltaic junction box with automatic shut-off capability according to claim 2, characterized in that: Positioning bases (7) are fixedly connected to the four corners of the bottom of the housing (101).

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