Photovoltaic combiner box and photovoltaic system

Abstract

The utility model provides a photovoltaic combiner box and a photovoltaic system. The photovoltaic combiner box is connected with a plurality of photovoltaic string groups which are connected in parallel, and each photovoltaic string group comprises a plurality of photovoltaic modules which are connected in series; the photovoltaic combiner box comprises a main circuit which is connected with photovoltaic string groups, and positive and negative outputs of each photovoltaic string group are converged to the main circuit to form a path of positive and negative outputs; the multi-pole switches are connected with the photovoltaic string groups in series; the control module is electrically connected with each multi-pole switch; wherein the multi-pole switch is configured to receive the first signal output by the control module, and conduct or disconnect positive and negative output paths of each photovoltaic module in the photovoltaic string group at the same time. Thus, when a photovoltaic module of the photovoltaic combiner box breaks down, the whole photovoltaic combiner box does not need to be cut off, only the multi-pole switch corresponding to the fault photovoltaic module needs to be cut off, other photovoltaic string groups can still work normally, the failure of the whole photovoltaic combiner box caused by the fault of a single photovoltaic module is avoided, and the power generation loss of the photovoltaic combiner box is reduced.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic technology, and in particular to a photovoltaic combiner box and a photovoltaic system. Background Technology

[0002] The main function of a photovoltaic combiner box is to collect the current output from photovoltaic modules and transmit it to the inverter, while also providing basic functions such as overcurrent protection, overvoltage protection, and monitoring.

[0003] In related technologies, when a photovoltaic module in a photovoltaic combiner box circuit malfunctions, the entire photovoltaic combiner box circuit needs to be disconnected, causing all photovoltaic modules connected to the combiner box to stop working, resulting in a loss of power generation from the photovoltaic combiner box.

[0004] Therefore, how to increase the power generation of photovoltaic combiner boxes has become an urgent problem to be solved. Utility Model Content

[0005] This invention provides a photovoltaic combiner box and a photovoltaic system to reduce the power generation loss of the photovoltaic combiner box.

[0006] This utility model is implemented as follows: It provides a photovoltaic combiner box and a photovoltaic system. The photovoltaic combiner box includes: multiple parallel photovoltaic string groups, each photovoltaic string group including multiple photovoltaic modules connected in series; a main circuit connected to the photovoltaic string groups, wherein the positive and negative outputs of each photovoltaic string group are combined into a single positive and negative output path; multiple multi-pole switches connected in series with the photovoltaic string groups; and a control module electrically connected to each of the multi-pole switches. The multi-pole switches are configured to receive a first signal output by the control module and simultaneously connect or disconnect the positive and negative output paths of each photovoltaic module in the photovoltaic string group.

[0007] Furthermore, the photovoltaic combiner box also includes a first sampling point located at the output end of the photovoltaic string group. The control module samples the output voltage and / or output current of the photovoltaic string group through the first sampling point.

[0008] Furthermore, the photovoltaic combiner box also includes a second sampling point located in the main circuit. The control module samples the input voltage and / or input current of the main circuit through the second sampling point.

[0009] Furthermore, the photovoltaic combiner box also includes a button circuit, which is electrically connected to the multi-pole switch. The multi-pole switch is also configured to receive a button signal output by the button circuit and simultaneously connect or disconnect the positive and negative output paths of each photovoltaic module in one or more of the photovoltaic string groups.

[0010] Furthermore, the photovoltaic combiner box also includes a protection device located in the main circuit. The protection device is electrically connected to the control module and is configured to receive a second signal output by the control module to turn the main circuit on or off.

[0011] Furthermore, the protection device is a fuse, relay, circuit breaker, or crystal switch.

[0012] Furthermore, the control module includes a communication module, through which the control module communicates with external devices.

[0013] This utility model embodiment also provides a photovoltaic system, which includes a photovoltaic inverter, a power grid, and a photovoltaic combiner box as described above; the output terminal of the photovoltaic combiner box is electrically connected to the input terminal of the photovoltaic inverter, and the output terminal of the photovoltaic inverter is electrically connected to the power grid.

[0014] Furthermore, the photovoltaic system also includes a back-end controller, which is communicatively connected to the photovoltaic combiner box.

[0015] In this embodiment of the invention, the photovoltaic combiner box is connected in series with the photovoltaic strings via a multi-pole switch. The multi-pole switch is configured to receive the first signal output by the control module and simultaneously connect or disconnect the positive and negative output paths of each photovoltaic module in one or more photovoltaic strings. This allows the photovoltaic combiner box to continue operating normally without shutting down the entire box when a photovoltaic module fails. Only the multi-pole switch corresponding to the failed photovoltaic module needs to be disconnected. This avoids the failure of the entire photovoltaic combiner box due to the failure of a single photovoltaic module, reduces the power generation loss of the photovoltaic combiner box, and improves the overall operational reliability and stability of the photovoltaic combiner box. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 A schematic diagram of the module structure of a photovoltaic combiner box provided in an embodiment of this utility model;

[0018] Figure 2 A schematic diagram of the circuit structure of a photovoltaic combiner box provided in an embodiment of this utility model;

[0019] Figure 3A schematic diagram of the connection module of the button circuit in a photovoltaic combiner box provided in an embodiment of this utility model;

[0020] Figure 4 This is a schematic diagram of a photovoltaic system module structure provided in an embodiment of the present invention.

[0021] Key component symbols: 1000, Photovoltaic system; 100, Photovoltaic string; 200, Photovoltaic combiner box; 300, Photovoltaic inverter; 400, Power grid; 500, Back-end controller; 101, Photovoltaic module; 10, Main circuit; 20, Multi-pole switch; 30, Control module; 40, Keypad circuit; 50, Protection device; 31, Communication module; A, First sampling point; B, Second sampling point. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present utility model, and should not be construed as limiting the present utility model. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining the present utility model and are not intended to limit the present utility model.

[0023] In the description of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "top", "bottom", "lateral", "longitudinal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0024] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0026] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0027] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0028] Please see Figures 1 to 3This utility model provides a photovoltaic combiner box 200, which is connected to multiple parallel photovoltaic string groups 100. Each photovoltaic string group 100 includes multiple photovoltaic modules 101 connected in series. The photovoltaic combiner box 200 includes: a main circuit 10, multiple multi-pole switches 20, and a control module 30. The multiple photovoltaic string groups 100 are connected in parallel, and each photovoltaic string group 100 includes multiple photovoltaic modules 101 connected in series. The main circuit 10 is connected to the photovoltaic string groups 100, and the positive and negative outputs of the photovoltaic string groups 100 are combined into a single positive and negative output path in the main circuit 10. The multi-pole switches 20 are connected in series with the photovoltaic string groups 100. The control module 30 is electrically connected to each multi-pole switch 20. The multi-pole switches 20 are configured to receive a first signal output by the control module 30, and simultaneously conduct or disconnect the positive and negative output paths of each photovoltaic module 101 in one or more photovoltaic string groups 100.

[0029] Thus, in this embodiment of the invention, the photovoltaic combiner box 200 is connected in series with the photovoltaic string group 100 via a multi-pole switch 20. The multi-pole switch 20 is configured to receive the first signal output by the control module 30, and simultaneously connect or disconnect the positive and negative output paths of each photovoltaic module 101 in one or more photovoltaic string groups 100. This allows the photovoltaic combiner box 200 to continue operating normally without disconnecting the entire photovoltaic combiner box 200 when a photovoltaic module 101 fails, simply disconnecting the multi-pole switch 20 corresponding to the failed photovoltaic module 101, while the other photovoltaic string groups 100 continue to operate normally, reducing power generation losses in the photovoltaic combiner box 200. It also avoids backflow caused by short circuits in photovoltaic modules 101. Furthermore, it prevents the entire photovoltaic combiner box 200 from failing due to the failure of a single photovoltaic module 101, improving the overall operational reliability and stability of the photovoltaic combiner box 200.

[0030] Specifically, the photovoltaic combiner box 200 is connected to multiple photovoltaic string groups 100, each of which includes multiple photovoltaic modules 101 connected in series. Each photovoltaic string group 100 is connected in parallel. The positive and negative outputs of each photovoltaic string group 100 are connected to the main circuit 10 via a busbar. Furthermore, the positive and negative outputs of each photovoltaic module 101 in the photovoltaic combiner box 200 are also connected to one positive and one negative output of the main circuit 10 via a busbar. The output terminals of the photovoltaic modules 101 are correspondingly connected to the input terminals of the main circuit 10.

[0031] A multi-pole switch 20 is connected in series with a photovoltaic string 100, meaning that the multi-pole switch 20 can connect or disconnect the positive and negative output paths of each photovoltaic module 101 in the photovoltaic string 100. For example, when the multi-pole switch 20 is closed, the output path of each photovoltaic module 101 in the photovoltaic string 100 connected to the multi-pole switch 20 is connected. When the multi-pole switch 20 is open, the output path of each photovoltaic module 101 in the photovoltaic string 100 connected to the multi-pole switch 20 is disconnected.

[0032] Each corresponding multi-pole switch 20 is independent, and the closing or opening of one multi-pole switch 20 will not affect the closing or opening of other multi-pole switches 20. Therefore, when a photovoltaic module 101 fails in one or more photovoltaic string groups 100, closing or opening the photovoltaic string group 100 corresponding to the failed photovoltaic string group 100 will not affect the normal operation of the photovoltaic modules 101 in other photovoltaic string groups 100. Therefore, in the photovoltaic combiner box 200 of this utility model embodiment, by disconnecting the output path of a specific photovoltaic string group 100, the output path of the failed photovoltaic module 101 can be isolated without affecting the normal operation of other photovoltaic string groups 100.

[0033] At the same time, the multi-pole switch 20 has a low cost, which can also achieve the effect of cost saving.

[0034] Please see Figure 1 and Figure 2 Furthermore, the control module 30 is electrically connected to each multi-pole switch 20, and the control module 30 can control the closing or opening of the multi-pole switch 20 by outputting a first signal. At the same time, the control module 30 is independently electrically connected to each multi-pole switch 20, and the control of the multi-pole switch 20 by the control module 30 will not affect the closing or opening of other multi-pole switches 20.

[0035] Specifically, the control module 30 may include a field-programmable gate array (FPGA), a microcontroller, or a microprocessor. The control module 30 may use an FPGA, a microcontroller, or a microprocessor as its core component. The specific choice depends on the complexity, real-time requirements, and cost factors of the control module 30, in order to achieve the flexibility of the control module 30.

[0036] For example, control module 30 may include a field-programmable gate array (FPGA) of model XC6SLX9, EP4CE6E22C8N, or XC7A35T. For example, control module 30 may include a microcontroller of model Atmel ATmega2560, Microchip PIC16F877A, or STMicroelectronics STM32F103C8T6. For example, control module 30 may include a microcontroller chip of model NXPLPC1768, Texas Instruments TMS320F28069, or LPC1768.

[0037] Please see Figure 1 and Figure 2 In one possible implementation, the photovoltaic combiner box 200 further includes a first sampling point A, located at the output terminal of the photovoltaic string group 100. The control module 30 samples the output voltage and / or output current of the photovoltaic string group 100 through the first sampling point A. Thus, the control module 30 can sample the voltage and / or current at the first sampling point A to promptly detect which photovoltaic string group 100 is malfunctioning and accordingly open or close the corresponding multi-pole switch 20.

[0038] Specifically, the number of first sampling points A corresponds to the number of photovoltaic string groups 100. The first sampling point A is specifically located between the photovoltaic string group 100 and the main circuit 10. The control module 30 samples the first sampling point A and can sample the specific output voltage and output current of the corresponding photovoltaic string group 100.

[0039] Please see Figure 1 and Figure 2 In one possible implementation, the photovoltaic combiner box 200 further includes a second sampling point B, located in the main circuit 10. The control module 30 samples the input voltage and / or input current of the main circuit 10 through the second sampling point B. Thus, the control module 30 can sample the voltage and / or current at the second sampling point B to monitor the total voltage and / or total current of the main circuit 10 in a timely manner, and accordingly determine whether a faulty photovoltaic string 100 has appeared in the photovoltaic combiner box 200.

[0040] Please see Figures 1 to 3In one possible implementation, the photovoltaic combiner box 200 further includes a button circuit 40, which is electrically connected to each multi-pole switch 20. The multi-pole switch 20 is configured to receive button signals output from the button circuit 40, simultaneously connecting or disconnecting the positive and negative output paths of each photovoltaic module 101 in one or more photovoltaic string groups 100. Thus, the multi-pole switches 20 can be opened and closed not only through the control module 30 but also through the button circuit 40. The multi-pole switches 20 can receive both automatic signals from the control module 30 and manual button signals from the button circuit 40. Users can switch between automatic control and manual operation as needed to improve the flexibility of the multi-pole switch 20 control.

[0041] Meanwhile, when the control module 30 malfunctions, the user can manually control the multi-pole switch 20 through the button circuit 40, which further improves the safety of the photovoltaic combiner box 200.

[0042] The number of button circuits 40 can correspond to the number of multi-pole switches 20, that is, one button circuit 40 is connected to one multi-pole switch 20. This allows the user to manually select which multi-pole switch 20 is closed or open, improving the flexibility of the multi-pole switch 20 settings.

[0043] Please see Figure 1 and Figure 2 In one possible implementation, the photovoltaic combiner box 200 includes a protection device 50 located in the main circuit 10. The protection device is electrically connected to the control module 30 and is configured to receive a second signal output by the control module 30 to turn the main circuit 10 on or off. Thus, when the photovoltaic combiner box 200 malfunctions, the protection device 50 can receive the second signal output by the control module 30 and quickly disconnect the main circuit 10, preventing abnormal current or overload from damaging the core circuit of the photovoltaic combiner box 200, thereby improving the safety of the photovoltaic combiner box 200.

[0044] Meanwhile, the protection device 50 and the multi-pole switch 20 form a multi-level protection for the photovoltaic combiner box 200. The multi-pole switch 20 is responsible for the individual control of the photovoltaic string group 100 and can isolate local faults in the photovoltaic combiner box 200 circuit. The protection device 50 provides global protection for the photovoltaic combiner box 200 and can disconnect the main circuit 10 in a timely manner. The multi-level protection formed by the protection device 50 and the multi-pole switch 20 further improves the safety and stability of the photovoltaic combiner box 200.

[0045] In addition, the protection device 50 can also prevent backflow. To prevent backflow, the protection device 50 is located in the main circuit 10. In this way, in the event of backflow, the protection device 50 can be disconnected to prevent backflow and extend the service life of the photovoltaic combiner box 200.

[0046] Specifically, the protection device 50 can be configured as a fuse, relay, circuit breaker or crystal switch.

[0047] Please see Figure 1 and Figure 2 In one possible implementation, the control module 30 includes a communication module 31, through which the control module 30 communicates with external devices. Thus, the control module 30 can communicate with external devices via the communication module 31, enhancing the intelligence level and remote management capabilities of the photovoltaic combiner box 200.

[0048] Specifically, the control module 30 can transmit the operating data (such as voltage, current, temperature, fault status, etc.) of the photovoltaic combiner box 200 to external devices (such as monitoring systems, cloud platforms, or mobile terminals) via the communication module 31, allowing maintenance personnel to monitor the equipment status of the photovoltaic combiner box 200 at any time. Simultaneously, in the event of a fault or when adjustments to the photovoltaic combiner box 200 are required, maintenance personnel can send control commands via external devices. Upon receiving these commands, the control module 30 will trigger the multi-pole switch 20 or the protection device 50 to isolate faults in the photovoltaic combiner box 200 circuit in a timely manner.

[0049] Specifically, the communication module 31 may include an RS485 interface, a CAN bus interface, a Wi-Fi module, a 4G / 5G module, etc.

[0050] like Figure 4 As shown, the photovoltaic system 1000 in this embodiment of the present invention includes: a photovoltaic inverter 300, a power grid 400, and the aforementioned photovoltaic combiner box 200. The output terminal of the photovoltaic combiner box 200 is electrically connected to the input terminal of the photovoltaic inverter 300, and the output terminal of the photovoltaic inverter 300 is electrically connected to the power grid 400.

[0051] Specifically, the main function of the photovoltaic inverter 300 is to convert the direct current output from the photovoltaic combiner box 200 into alternating current, and then output the alternating current to the power grid 400. The input terminal of the photovoltaic inverter 300 is electrically connected to the output terminal of the photovoltaic combiner box 200. In this way, the photovoltaic combiner box 200 can transmit electrical energy to the photovoltaic inverter 300 for conversion and output to the power grid 400, thereby providing clean energy to the power grid 400.

[0052] Furthermore, in one possible implementation, the photovoltaic system 1000 also includes a back-end controller 500, which is communicatively connected to the photovoltaic combiner box 200. Thus, through the configuration of the back-end controller 500, centralized monitoring and optimized control of the photovoltaic combiner box 200 can be achieved.

[0053] Specifically, the background controller 500 can communicate and coordinate with the photovoltaic combiner box 200 to obtain the operating status information of the photovoltaic combiner box 200.

[0054] The backend controller 500 can connect to the photovoltaic combiner box 200 via a communication interface to obtain the operating status data of each component within the photovoltaic combiner box 200. The backend controller 500 can analyze the power generation efficiency of the entire system using this data and make adjustments. In case of abnormalities, such as a malfunction of the photovoltaic combiner box 200 or a power output that does not meet standards, the backend controller 500 can send alarm or control signals, activate the protection mechanism, and shut down the photovoltaic combiner box 200 to ensure the safety of the photovoltaic system 1000.

[0055] In the description of this specification, the references to terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0056] Furthermore, the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A photovoltaic combiner box, characterized by, The photovoltaic combiner box is connected with a plurality of parallel photovoltaic string groups, each of the photovoltaic string groups comprising a plurality of series photovoltaic modules; the photovoltaic combiner box comprises: a main circuit connected with the photovoltaic string groups, the positive and negative outputs of each of the photovoltaic string groups being connected to the main circuit as a positive and negative output; a plurality of multi-pole switches connected in series with the photovoltaic string groups; a control module electrically connected with each of the multi-pole switches; wherein the multi-pole switches are configured to receive a first signal output by the control module and simultaneously turn on or off the positive and negative output paths of each of the photovoltaic modules in the photovoltaic string groups.

2. The PV combiner box of claim 1, wherein, Further comprising a first sampling point at the output of the photovoltaic string groups, the control module sampling the output voltage and / or output current of the photovoltaic string groups through the first sampling point.

3. The PV combiner box of claim 1, wherein, Further comprising a second sampling point at the main circuit, the control module sampling the input voltage and / or input current of the main circuit through the second sampling point.

4. The PV combiner box of claim 1, wherein, Further comprising a key circuit electrically connected with the multi-pole switches, the multi-pole switches being further configured to receive a key signal output by the key circuit and simultaneously turn on or off the positive and negative output paths of each of the photovoltaic modules in one or more of the photovoltaic string groups.

5. The photovoltaic combiner box of claim 1, wherein, Further comprising a protection device at the main circuit, the protection device being electrically connected with the control module, the protection device being configured to receive a second signal output by the control module and turn on or off the main circuit.

6. The PV combiner box of claim 5, wherein, The protection device is a fuse, a relay, a circuit breaker or a crystal switch tube.

7. The PV combiner box of claim 1, wherein, The control module comprises a communication module, the control module communicating with external devices through the communication module.

8. A photovoltaic system characterized by, Comprising: a photovoltaic inverter, a power grid and the photovoltaic combiner box according to any one of claims 1 to 7; the output of the photovoltaic combiner box being electrically connected with the input of the photovoltaic inverter, the output of the photovoltaic inverter being electrically connected with the power grid.

9. The photovoltaic system of claim 8, wherein, Further comprising: a background controller, the background controller being communicatively connected with the photovoltaic combiner box.

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