Photovoltaic MPPT control cabinet

Abstract

The application relates to a photovoltaic MPPT control cabinet and relates to the technical field of photovoltaic power bus convergence and control equipment; the cabinet comprises a cabinet body, a bus convergence input unit arranged in the cabinet body, an MPPT control module and a bus convergence output unit; the output end of the bus convergence input unit is electrically connected with the input end of the MPPT control module, and the output end of the MPPT control module is electrically connected with the input end of the bus convergence output unit. The application has the effect of simplifying the system structure.

Description

Technical Field

[0001] This application relates to the technical field of photovoltaic power collection and control, and in particular to a photovoltaic MPPT control cabinet. Background Technology

[0002] In recent years, with the increasing global demand for clean energy, photovoltaic (PV) systems have been widely adopted as a sustainable energy solution. PV systems play a crucial role in the power supply sector, converting solar energy into electricity to provide clean, renewable energy to various users, reducing dependence on traditional fossil fuels, and contributing to energy conservation, emission reduction, and environmental protection goals. During its development, PV systems have achieved significant results in energy structure adjustment and carbon emission reduction, and have been extensively applied in various scenarios such as industrial and commercial distributed PV, agricultural-photovoltaic hybrid projects, fishery-photovoltaic hybrid projects, and photovoltaic-storage-charging systems.

[0003] Traditional photovoltaic (PV) systems commonly employ a combiner box + independent MPPT controller architecture. The combiner box only performs the physical function of current collection; it simply aggregates the current from multiple PV strings and outputs it to the MPPT controller. Traditional combiner MPPT control systems often use discrete component designs. Specifically, cables run from the PV panels to the combiner box for current collection, and the output cables from the combiner box are then run to the MPPT controller. In this architecture, a large number of DC cables of varying specifications need to be laid to connect the PV panels to the combiner box and the combiner box to the MPPT controller.

[0004] Traditional architectures have significant drawbacks. The need to lay a large number of DC cables of varying specifications leads to extremely high wiring complexity, increasing the difficulty of installation and maintenance. Furthermore, the procurement and laying of cables is a substantial expense, raising the overall system cost. Moreover, the existing combiner box is separated from the MPPT control function, complicating troubleshooting and making it difficult to quickly and accurately locate the problem when a system failure occurs, thus impacting system reliability and operational efficiency. Utility Model Content

[0005] To simplify the system structure, this application provides a photovoltaic MPPT control cabinet.

[0006] The photovoltaic MPPT control cabinet provided in this application adopts the following technical solution: A photovoltaic MPPT control cabinet includes a cabinet body and a current input unit, an MPPT control module, and a current output unit disposed within the cabinet body; the output terminal of the current input unit is electrically connected to the input terminal of the MPPT control module, and the output terminal of the MPPT control module is electrically connected to the input terminal of the current output unit.

[0007] By adopting the above technical solution, the functions of traditionally distributed combiner boxes and MPPT controllers are integrated into one cabinet, simplifying the system structure of photovoltaic power stations, reducing the workload of on-site installation and wiring, and improving the overall integrity and reliability of the system.

[0008] Preferably, the bus input unit includes multiple first fuses and multiple input circuit breakers; each photovoltaic string corresponds to one of the input circuit breakers and one of the MPPT control modules; the connection terminal of each photovoltaic string is electrically connected to one end of the corresponding input circuit breaker through the first fuse, and the other end of the input circuit breaker is electrically connected to the input terminal of the corresponding MPPT control module.

[0009] By adopting the above technical solution, each photovoltaic string is equipped with an independent circuit breaker and MPPT controller, achieving refined management at the string level. If any string experiences a fault (such as a short circuit or overcurrent), its corresponding circuit breaker can trip independently without affecting the power generation of other normal strings, greatly improving the system's reliability and power generation.

[0010] Preferably, the bus input unit further includes an input busbar; the ends of multiple first fuses furthest from the photovoltaic string are uniformly connected to the input terminal of the input busbar, and the output terminal of the input busbar is electrically connected to one end of the input circuit breaker; the number of the input busbars is the same as the number of the MPPT control modules.

[0011] By adopting the above technical solution and setting up an input busbar, the number of connection points is reduced, the contact resistance and the risk of local overheating are lowered, and the electrical connection is made cleaner and more reliable.

[0012] Preferably, the bus output unit includes multiple second fuses, an output circuit breaker QF, and an output busbar; the output terminals of the multiple MPPT control modules are respectively electrically connected to one end of the output circuit breaker through the second fuses, and the other end of the output circuit breaker is used for output; the output busbar is used to collect the current output by the multiple MPPT control modules to the output circuit breaker.

[0013] By adopting the above technical solution, the second fuse provides overcurrent protection for the output circuit of each MPPT control module. The output circuit breaker QF can control the on / off state of the entire control cabinet's output and provide overall protection.

[0014] Preferably, the bus output unit further includes an output busbar, which is used to collect the current output by the multiple MPPT control modules to the output circuit breaker.

[0015] By adopting the above technical solution and setting up an output busbar, the number of connection points is reduced.

[0016] Preferably, the bus output unit further includes a surge protection module, one end of which is electrically connected to the input side of the output circuit breaker, and the other end is grounded; the surge protection module includes a surge protector and a surge protection circuit breaker.

[0017] By adopting the above technical solutions, damage to expensive electronic equipment such as MPPT control modules inside the cabinet by lightning surge currents entering from the output line is prevented, thereby improving the system's survivability and reliability in severe weather.

[0018] Preferably, the cabinet body is provided with a modular support plate, and multiple slide rails are arranged in parallel on the modular support plate; the MPPT control module is slidably connected to the adjacent slide rails on both sides near the slide rails.

[0019] By adopting the above technical solutions, installation, debugging, and subsequent maintenance and replacement are greatly facilitated, reducing downtime.

[0020] In summary, this application includes at least one of the following beneficial technical effects: 1. Integrating DC bus and MPPT functions into a single cabinet improves system reliability and reduces maintenance difficulty, solving the problems of complex cabling and troublesome fault location in traditional architectures; 2. The photovoltaic MPPT control cabinet, by setting multiple protections of fuses and circuit breakers in the input and output circuits, and integrating a lightning protection module including a lightning protection circuit breaker on the output side, constructs a complete overcurrent, short circuit and surge protection system. Attached Figure Description

[0021] Figure 1 This is a circuit diagram of an embodiment of this application; Figure 2 This is a schematic diagram of the structure of the bus input unit in the embodiments of this application; Figure 3 This is a schematic diagram of the structure of the bus output unit in the embodiments of this application; Figure 4 This is a schematic diagram of the MPPT control module in an embodiment of this application.

[0022] Reference numerals in the attached diagram: 1. Bus input unit; 11. First fuse; 12. Input circuit breaker; 13. Input busbar; 2. MPPT control module; 3. Bus output unit; 31. Second fuse; 32. Output circuit breaker; 33. Output busbar; 34. Lightning protection module; 341. Lightning protection circuit breaker; 342. Lightning arrester; 4. Module support plate; 5. Slide rail. Detailed Implementation

[0023] The following combination Figures 1-4This application will be described in further detail.

[0024] This application discloses a photovoltaic MPPT control cabinet.

[0025] Reference Figure 1 A photovoltaic MPPT control cabinet includes a cabinet body, and a combiner input unit 1, an MPPT control module 2, and a combiner output unit 3 disposed within the cabinet body. The output terminal of the combiner input unit 1 is electrically connected to the input terminal of the MPPT control module 2, and the output terminal of the MPPT control module 2 is electrically connected to the input terminal of the combiner output unit 3. The electrical energy generated by the photovoltaic string passes sequentially through the combiner input unit 1, the MPPT control module 2, and the combiner output unit 3 before being output externally.

[0026] Reference Figure 1 , Figure 2 and Figure 3 The bus input unit 1 includes multiple first fuses 11 and multiple input circuit breakers 12, and the bus output unit includes multiple second fuses 31 and an output circuit breaker 32QF. Each photovoltaic string includes multiple connection terminals, and each photovoltaic string corresponds to an input circuit breaker 12 and an MPPT control module 2. Each connection terminal is electrically connected to one end of the input circuit breaker 12 corresponding to the photovoltaic string to which the connection terminal belongs through a first fuse 11. One end of the input circuit breaker 12 is electrically connected to the input terminal of the MPPT control module 2 corresponding to the photovoltaic string. The output terminals of the multiple MPPT control modules 2 are respectively electrically connected to one end of the output circuit breaker 32QF through second fuses 31. The other end of the output circuit breaker 32QF serves as the system's total output.

[0027] Preferably, the bus input unit 1 further includes an input busbar 13. The ends of the multiple first fuses 11 furthest from the photovoltaic strings are uniformly connected to the input terminals of the input busbar 13, and the output terminals of the input busbar 13 are then electrically connected to one end of the input circuit breaker 12. The number of input busbars 13 is the same as the number of MPPT control modules 2. The input busbars can collect the current output from multiple photovoltaic strings together, allowing them to be connected to the MPPT control modules 2 with fewer branches.

[0028] Reference Figure 3The cabinet also houses multiple module support plates 4, on which the first fuse 11, the second fuse 31, the DC circuit breaker, and the MPPT control module 2 are all mounted. The first fuse 11 and the second fuse 31 are generally high-breaking-capacity fuses, capable of quickly cutting off the circuit and effectively preventing overcurrent damage to the equipment; alternatively, current-limiting fuses can be used to limit the magnitude of the short-circuit current. The connection terminal above the first fuse 11 is electrically connected to the corresponding input busbar 13 via a wire, and the input busbar 13 is fixed to the input circuit breaker 12. The first fuse 11 provides overcurrent protection for each input circuit; when the current in a certain circuit is too high, the first fuse 11 will melt, cutting off that circuit. The input circuit breaker 12 controls the connection and disconnection of the photovoltaic string to the photovoltaic MPPT module, facilitating equipment inspection and maintenance.

[0029] Reference Figure 4 Multiple MPPT control modules 2 are stacked and arranged in a stacked manner. Each MPPT control module 2 is rectangular in shape, and multiple slide rails 5 are arranged parallel to each other on the module support plate 4. The length direction of the slide rail 5 is parallel to the length direction of the MPPT control module 2, and the MPPT control module 2 is positioned between two adjacent slide rails 5. The sides of the MPPT control module 2 closest to the slide rail 5 are slidably connected to the adjacent slide rail 5. Through the above sliding connection structure, the MPPT control module 2 can be detachably assembled, facilitating the installation, disassembly, and replacement of the MPPT control module 2.

[0030] Specifically, the busbar output unit 3 also includes an output busbar 33 and a surge protection module 34. The surge protection module 34 includes a surge protector 342 and a surge circuit breaker 341. One end of the surge protection module 34 is electrically connected to the side of the output circuit breaker 32 furthest from the output end, and the other end of the surge protection module 34 is grounded. The output busbar 33 collects the electricity output from multiple MPPT modules together. In the event of a lightning strike, the surge protection module 34 can conduct the lightning current to the ground, thus providing lightning protection. The DC molded case circuit breaker at the output end, also known as the output circuit breaker 32, controls the grid connection of the photovoltaic MPPT control cabinet. When the output circuit breaker 32 is closed, it enables the photovoltaic MPPT control cabinet to be directly coupled to the external system.

[0031] The input bus 1 and the MPPT control module 2 form the first-stage bus, which integrates the current from multiple photovoltaic strings into a branch current matching the number of MPPT control modules 2, reducing the number of branches connected to MPPT control modules 2. The output bus 2 and the output bus 3 form the second-stage bus, which integrates the output current of MPPT control modules 2 into a single output branch, facilitating the output of electrical energy. Simultaneously, the number of fuses in the input bus 1 matches the number of photovoltaic strings, and the number of output fuses in the output bus 3 matches the number of MPPT control modules 2, ensuring effective overcurrent protection for each input and output.

[0032] The implementation principle of this embodiment is as follows: The photovoltaic MPPT control cabinet of this embodiment integrates the current collection and MPPT functions into one cabinet. Through a two-stage current collection architecture, it collects and processes the electrical energy generated by the photovoltaic string. The current collection input unit 1 collects and protects the current input to the photovoltaic string, while the MPPT control module 2 implements string-level maximum power point tracking control, enabling the photovoltaic string to operate at its maximum power point and improving the energy conversion efficiency. The current collection output unit 3 collects the current output from the MPPT control module 2 again and outputs it, while also providing functions such as lightning protection. The overall cabinet design reduces the laying of a large number of DC cables, lowers wiring complexity and cost, and makes fault diagnosis easier, thereby improving the reliability and operation and maintenance efficiency of the system.

[0033] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A photovoltaic MPPT control cabinet, characterized in that: It includes a cabinet and a bus input unit (1), an MPPT control module (2) and a bus output unit (3) disposed in the cabinet; the output end of the bus input unit (1) is electrically connected to the input end of the MPPT control module (2), and the output end of the MPPT control module (2) is electrically connected to the input end of the bus output unit (3).

2. The photovoltaic MPPT control cabinet according to claim 1, characterized in that: The bus input unit (1) includes multiple first fuses (11) and multiple input circuit breakers (12); each photovoltaic string corresponds to one of the input circuit breakers (12) and one of the MPPT control modules (2); the connection end of each photovoltaic string is electrically connected to one end of the corresponding input circuit breaker (12) through the first fuse (11), and the other end of the input circuit breaker (12) is electrically connected to the input end of the corresponding MPPT control module (2).

3. A photovoltaic MPPT control cabinet according to claim 2, characterized in that: The bus input unit (1) further includes an input busbar (13); the ends of multiple first fuses (11) away from the photovoltaic string are uniformly connected to the input end of the input busbar (13), and the output end of the input busbar (13) is electrically connected to one end of the input circuit breaker (12); the number of the input busbars (13) is the same as the number of the MPPT control modules (2).

4. A photovoltaic MPPT control cabinet according to claim 1, characterized in that: The bus output unit (3) includes multiple second fuses (31), an output circuit breaker (32) QF, and an output busbar (33); the output terminals of multiple MPPT control modules (2) are respectively electrically connected to one end of the output circuit breaker (32) through the second fuses (31), and the other end of the output circuit breaker (32) is used for output; the output busbar (33) is used to collect the current output by multiple MPPT control modules (2) to the output circuit breaker (32).

5. A photovoltaic MPPT control cabinet according to claim 4, characterized in that: The bus output unit (3) further includes an output busbar (33), which is used to collect the current output by the multiple MPPT control modules (2) to the output circuit breaker (32).

6. A photovoltaic MPPT control cabinet according to claim 5, characterized in that: The bus output unit (3) also includes a lightning protection module (34), one end of which is electrically connected to the input side of the output circuit breaker (32), and the other end is grounded; the lightning protection module (34) includes a lightning arrester (342) and a lightning protection circuit breaker (341).

7. A photovoltaic MPPT control cabinet according to claim 1, characterized in that: The cabinet is equipped with a module support plate (4), and multiple slide rails (5) are arranged in parallel on the module support plate (4); the MPPT control module (2) is slidably connected to the adjacent slide rails (5) on both sides near the slide rails (5).

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