Photovoltaic power generation cascade circuit and photovoltaic power generation equipment

Abstract

The utility model provides a photovoltaic power generation cascade circuit and photovoltaic power generation equipment, and relates to the photovoltaic field, and the photovoltaic power generation cascade circuit realizes parallel switching of MPPT controllers in photovoltaic power generation branches through a photovoltaic power generation main circuit and two-way switches arranged in a plurality of photovoltaic power generation branches which are connected in parallel with each other. The power generation power in the photovoltaic power generation branch circuit can be integrally input into the photovoltaic power generation main circuit in parallel under the condition that the power generation efficiency is relatively low, so that the input power of the MPPT controller in the photovoltaic power generation main circuit is improved, the low-power tracking conversion loss is reduced, the overall tracking efficiency is improved, and the photovoltaic power generation efficiency is favorably improved.

Description

Technical Field

[0001] The utility model relates to the field of photovoltaic power generation, in particular to a photovoltaic power generation cascade circuit and a photovoltaic power generation device. Background Art

[0002] The core device in the photovoltaic power generation control system is the maximum power point tracking controller, that is, the MPPT (Maximum Power Point Tracking) controller, which can detect the generated voltage of the solar panel in real time and track the highest voltage and current values, so that all photovoltaic modules can charge the storage battery with the maximum power output. In actual scenarios, the power generation efficiency of photovoltaic modules is relatively low under insufficient sunlight conditions and at night. The input power of the MPPT controller is insufficient, resulting in small power tracking conversion losses, thus affecting the overall tracking efficiency and reducing the power generation efficiency of photovoltaic power generation. Summary of the Utility Model

[0003] In view of this, the purpose of the utility model is to provide a photovoltaic power generation cascade circuit and a photovoltaic power generation device. The circuit realizes the parallel switching of the MPPT controllers in the photovoltaic power generation branches through the double - path switches arranged in the photovoltaic power generation main path and multiple mutually - parallel photovoltaic power generation branches. It can integrally parallel - input the generated power in the photovoltaic power generation branches into the photovoltaic power generation main path under the condition of low power generation efficiency, thereby increasing the input power of the MPPT controller in the photovoltaic power generation main path, reducing the small - power tracking conversion loss, improving the overall tracking efficiency, and being beneficial to improving the photovoltaic power generation efficiency.

[0004] In the first aspect, an embodiment of the utility model provides a photovoltaic power generation cascade circuit, which includes: a photovoltaic power generation main path and multiple photovoltaic power generation branches;

[0005] Among them, the photovoltaic power generation main path includes: a first photovoltaic module, a first double - path switch, a first diode, a first maximum power point tracking controller, and an inverter; the first photovoltaic module is connected to the input end of the first double - path switch; the normally - open output end of the first double - path switch is connected to the positive electrode of the first diode; the negative electrode of the first diode and the normally - closed output end of the first double - path switch are both connected to the power supply input end of the first maximum power point tracking controller; the power supply output end of the first maximum power point tracking controller is connected to the inverter;

[0006] The photovoltaic power generation branch includes: a second photovoltaic module, a second two-way switch, and a second maximum power point tracking controller; the second photovoltaic module is connected to the input end of the second two-way switch; the normally closed output end of the second two-way switch is connected to the power supply input end of the second maximum power point tracking controller; the normally open output end of the second two-way switch is connected to the positive electrode of the first diode in the main photovoltaic power generation path; the power supply output end of the second maximum power point tracking controller is connected to the inverter.

[0007] In one embodiment, the main photovoltaic power generation path further includes: a second diode; the positive electrode of the second diode is connected to the normally closed output end of the first two-way switch; the negative electrode of the second diode is connected to the power supply input end of the first maximum power point tracking controller.

[0008] In one embodiment, both the first two-way switch and the second two-way switch are two-way switches built into a power relay.

[0009] In one embodiment, the first two-way switch is arranged in the first power relay; the power supply input pins in the first power relay are respectively connected to the input end of the first two-way switch and the first photovoltaic module; the first power supply output pin in the first power relay is respectively connected to the normally open output end of the first two-way switch and the positive electrode of the first diode; the second power supply output pin in the first power relay is respectively connected to the normally closed output end of the first two-way switch and the power supply input end of the first maximum power point tracking controller.

[0010] In one embodiment, the instruction output end of the first maximum power point tracking controller is connected to the instruction input pin in the first power relay; the instruction feedback end of the first maximum power point tracking controller is connected to the instruction feedback pin in the first power relay; wherein, a first coil is arranged in the first power relay, the input end of the first coil is connected to the instruction input pin in the first power relay; the output end of the first coil is connected to the instruction feedback pin in the first power relay; the first coil is used to switch the switch state of the first two-way switch.

[0011] In one embodiment, the second two-way switch is arranged in the second power relay; the power supply input pins in the second power relay are respectively connected to the input end of the second two-way switch and the second photovoltaic module; the first power supply output pin in the second power relay is respectively connected to the normally open output end of the second two-way switch and the positive electrode of the first diode; the second power supply output pin in the second power relay is respectively connected to the normally closed output end of the second two-way switch and the power supply input end of the second maximum power point tracking controller.

[0012] In one embodiment, the instruction output terminal of the second maximum power point tracking controller is connected to the instruction input pin in the second power relay; the instruction feedback terminal of the second maximum power point tracking controller is connected to the instruction feedback pin in the second power relay; wherein, a second coil is arranged in the second power relay, the input end of the second coil is connected to the instruction input pin in the second power relay; the output end of the second coil is connected to the instruction feedback pin in the second power relay; the second coil is used for switching the switch state of the second double-way switch.

[0013] In one embodiment, a first power supply port is arranged in the first maximum power point tracking controller, and the first power supply port is connected to the first photovoltaic module.

[0014] In one embodiment, a second power supply port is arranged in the second maximum power point tracking controller, and the second power supply port is connected to the second photovoltaic module.

[0015] In a second aspect, an embodiment of the present invention provides a photovoltaic power generation device, and this photovoltaic power generation device includes the photovoltaic power generation cascade circuit mentioned in the first aspect above.

[0016] A photovoltaic power generation cascade circuit and a photovoltaic power generation device provided by an embodiment of the present invention, this photovoltaic power generation cascade circuit includes: a main photovoltaic power generation path and a plurality of photovoltaic power generation branches. Among them, the main photovoltaic power generation path includes: a first photovoltaic module, a first double-way switch, a first diode, a first maximum power point tracking controller and an inverter; the first photovoltaic module is connected to the input end of the first double-way switch; the normally open output end of the first double-way switch is connected to the positive electrode of the first diode; the negative electrode of the first diode and the normally closed output end of the first double-way switch are both connected to the power supply input end of the first maximum power point tracking controller; the power supply output end of the first maximum power point tracking controller is connected to the inverter. The photovoltaic power generation branch includes: a second photovoltaic module, a second double-way switch, a second maximum power point tracking controller; the second photovoltaic module is connected to the input end of the second double-way switch; the normally closed output end of the second double-way switch is connected to the power supply input end of the second maximum power point tracking controller; the normally open output end of the second double-way switch is connected to the positive electrode of the first diode in the main photovoltaic power generation path; the power supply output end of the second maximum power point tracking controller is connected to the inverter. This photovoltaic power generation cascade circuit realizes the parallel switching of the MPPT controllers in the photovoltaic power generation branches through the double-way switches arranged in the main photovoltaic power generation path and its plurality of mutually parallel photovoltaic power generation branches, and can integrally parallel input the generated power in the photovoltaic power generation branches into the main photovoltaic power generation path when the power generation efficiency is low, so as to increase the input power of the MPPT controller in the main photovoltaic power generation path, reduce the small-power tracking conversion loss, improve the overall tracking efficiency, and is beneficial to improving the photovoltaic power generation efficiency.

[0017] Other features and advantages of the present utility model will be described in the subsequent specification, and in part will be obvious from the specification, or will be understood by implementing the present utility model. The objectives and other advantages of the present utility model are achieved and obtained by the structures specifically pointed out in the specification, claims, and drawings.

[0018] To make the above objectives, features, and advantages of the present utility model more obvious and understandable, the following specifically enumerates preferred embodiments and, in conjunction with the accompanying drawings, details are described as follows. Brief Description of the Drawings

[0019] To more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 Structural schematic diagram of the first photovoltaic cascaded circuit provided by an embodiment of the present utility model;

[0021] Figure 2 Structural schematic diagram of the second photovoltaic cascaded circuit provided by an embodiment of the present utility model;

[0022] Figure 3 Structural schematic diagram of the third photovoltaic cascaded circuit provided by an embodiment of the present utility model;

[0023] Figure 4 Structural schematic diagram of the fourth photovoltaic cascaded circuit provided by an embodiment of the present utility model;

[0024] Figure 5 Structural schematic diagram of the fifth photovoltaic cascaded circuit provided by an embodiment of the present utility model.

[0025] Reference Signs:

[0026] 10 - Main photovoltaic power generation path; 20 - Photovoltaic power generation branch; 30 - Inverter;

[0027] 10a - First photovoltaic module; 10b - First double - way switch; 10c - First maximum power point tracking controller; 10d - First diode; 10e - Second diode;

[0028] 20a - Second photovoltaic module; 20b - Second double - way switch; 20c - Second maximum power point tracking controller;

[0029] 11 - Power supply input pin of the first power relay; 12 - First power supply output pin of the first power relay; 13 - Second power supply output pin of the first power relay; 14 - Command input pin of the first power relay; 15 - Command feedback pin of the first power relay;

[0030] 21 - Power supply input pin of the second power relay; 22 - First power supply output pin of the second power relay; 23 - Second power supply output pin of the second power relay; 24 - Command input pin of the second power relay; 25 - Command feedback pin of the second power relay;

[0031] U1 - First power relay; U2 - Second power relay. Detailed implementation mode

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions of the present utility model will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.

[0033] The core device in the photovoltaic power generation control system is the MPPT controller, which can detect the generated voltage of the solar panel in real time and track the maximum voltage and current values, enabling all photovoltaic modules to charge the battery with the maximum power output. In actual scenarios, near the critical points of the illumination or temperature range of the photovoltaic modules, the overall efficiency of the maximum power tracking will be low due to insufficient input power. For example, during insufficient sunlight conditions and at night, the power generation efficiency of the photovoltaic modules is low, resulting in insufficient input power to the MPPT controller, thereby causing small-power tracking conversion losses, affecting the overall tracking efficiency, and reducing the efficiency of photovoltaic power generation. Based on this, the embodiments of the present utility model provide a photovoltaic power generation cascade circuit and a photovoltaic power generation device. The circuit realizes the parallel switching of the MPPT controllers in the photovoltaic power generation branches through the double-path switches arranged in the main photovoltaic power generation path and multiple mutually parallel photovoltaic power generation branches. When the power generation efficiency is low, the generated power in the photovoltaic power generation branches can be integrally and parallely input into the main photovoltaic power generation path, thereby increasing the input power of the MPPT controller in the main photovoltaic power generation path, reducing the small-power tracking conversion losses, improving the overall tracking efficiency, and being conducive to improving the efficiency of photovoltaic power generation.

[0034] To facilitate the understanding of this embodiment, first, a photovoltaic power generation cascade circuit disclosed in the embodiments of the present utility model will be introduced in detail, specifically as Figure 1 shown. The photovoltaic power generation cascade circuit includes: a main photovoltaic power generation path 10 and multiple photovoltaic power generation branches 20.

[0035] Among them, the main photovoltaic power generation path 10 includes: a first photovoltaic module 10a, a first two-way switch 10b, a first maximum power point tracking controller 10c, a first diode 10d, and an inverter 30; the first photovoltaic module 10a is connected to the input end of the first two-way switch 10b; the normally open output end of the first two-way switch 10b is connected to the positive pole of the first diode 10d; the negative pole of the first diode 10d and the normally closed output end of the first two-way switch 10b are both connected to the power supply input end of the first maximum power point tracking controller 10c; the power supply output end of the first maximum power point tracking controller 10c is connected to the inverter 30.

[0036] The photovoltaic power generation branch 20 includes: a second photovoltaic module 20a, a second two-way switch 20b, and a second maximum power point tracking controller 20c; the second photovoltaic module 20a is connected to the input end of the second two-way switch 20b; the normally closed output end of the second two-way switch 20b is connected to the power supply input end of the second maximum power point tracking controller 20c; the normally open output end of the second two-way switch 20b is connected to the positive pole of the first diode 10d in the main photovoltaic power generation path 10; the power supply output end of the second maximum power point tracking controller 20c is connected to the inverter 30.

[0037] Specifically, when the light is sufficient, the power generation efficiency of the photovoltaic module is relatively high, and the input power of the MPPT controller is sufficient. At this time, both the main photovoltaic power generation path 10 and each photovoltaic power generation branch 20 can use their own MPPT controllers. The photovoltaic power generation branch 20 transmits the power generation power of the second photovoltaic module 20a to the second maximum power point tracking controller 20c through its built-in second two-way switch 20b, and finally transmits it to the inverter 30 through the second maximum power point tracking controller 20c. Similarly, the main photovoltaic power generation path 10 transmits the power generation power of the first photovoltaic module 10a to the first maximum power point tracking controller 10c through the built-in first two-way switch 10b, and finally transmits it to the inverter 30.

[0038] When the light is insufficient and the power generation efficiency of the photovoltaic module is low, the input power of the MPPT controller is insufficient. At this time, if the main photovoltaic power generation path 10 and each photovoltaic power generation branch 20 use the MPPT controller, it will bring relatively high small-power tracking conversion losses and affect the overall tracking efficiency. At this time, each photovoltaic power generation branch 20 switches its built-in second two-way switch 20b to the normally open path, so that the power generation power of the second photovoltaic module 20a is directly transmitted to the main photovoltaic power generation path 10, and thus no longer input to the second maximum power point tracking controller 20c.

[0039] The main photovoltaic power generation path 10 also switches the built-in first dual-path switch 10b to the normally open path, so that the power generation power of the first photovoltaic module 10a and the power generation power of the second photovoltaic module 20a are combined and then transmitted to the first diode 10d. After being rectified by the first diode 10d, it is centrally transmitted to the first maximum power point tracking controller 10c. At this time, the power generation power of the first photovoltaic module 10a in the main photovoltaic power generation path 10 and the second photovoltaic modules 20a in all photovoltaic power generation branches 20 only input to the first maximum power point tracking controller 10c in the main photovoltaic power generation path 10. By the method of combining multiple paths into one path, the input power of the first maximum power point tracking controller 10c is increased, thereby reducing the conversion loss of small-power tracking and improving the overall tracking efficiency.

[0040] In one embodiment, as Figure 2 shown, the main photovoltaic power generation path further includes: a second diode 10e; the positive electrode of the second diode 10e is connected to the normally closed output end of the first dual-path switch 10b; the negative electrode of the second diode 10e is connected to the power supply input end of the first maximum power point tracking controller 10c. The second diode 10e is arranged in the normally closed path of the main photovoltaic power generation path 10 and is similar to the function of the first diode 10d. The second diode 10e is mainly used to rectify and stabilize the power generation power of the first photovoltaic module 10a.

[0041] As Figure 3 shown, in one embodiment, both the first dual-path switch 10b and the second dual-path switch 20b are dual-path switches built in a power relay. In the specific use process, other semiconductor devices can also be used to replace the power relay.

[0042] In one embodiment, the first dual-path switch 10b is arranged in the first power relay U1; the power supply input pin 11 in the first power relay U1 is respectively connected to the input end of the first dual-path switch 10b and the first photovoltaic module 10a; the first power supply output pin 12 in the first power relay U1 is respectively connected to the normally open output end of the first dual-path switch 10b and the positive electrode of the first diode 10d; the second power supply output pin 13 in the first power relay U1 is respectively connected to the normally closed output end of the first dual-path switch 10b and the power supply input end of the first maximum power point tracking controller 10c.

[0043] The first dual-path switch 10b in the first power relay U1 realizes the connection with the first photovoltaic module 10a and the first maximum power point tracking controller 10c through the power supply input pin 11, the first power supply output pin 12 and the second power supply output pin 13. During the specific connection process, only the above-mentioned pins need to be connected.

[0044] In one embodiment, the instruction output terminal of the first maximum power point tracking controller 10c is connected to the instruction input pin 14 in the first power relay U1; the instruction feedback terminal of the first maximum power point tracking controller 10c is connected to the instruction feedback pin 15 in the first power relay U1. Wherein, a first coil is provided in the first power relay U1, the input end of the first coil is connected to the instruction input pin 14 in the first power relay U1; the output end of the first coil is connected to the instruction feedback pin 15 in the first power relay U1; the first coil is used to switch the switching state of the first double-path switch 10b. The first coil directly controls the switching state of the first double-path switch. Generally speaking, the first coil is the control unit of the first double-path switch. The control instruction of the first coil is sent through the instruction output terminal of the first maximum power point tracking controller 10c and received by the instruction input pin 14 in the first power relay U1. The working state of the first coil is fed back to the instruction feedback terminal of the first maximum power point tracking controller 10c through the generated feedback instruction by using the instruction feedback pin 15 in the first power relay U1. The first coil in the first power relay U1 is connected to the first maximum power point tracking controller 10c through the instruction input pin 14 and the instruction feedback pin 15. In the specific connection process, only the above-mentioned pins need to be connected.

[0045] In one embodiment, the second double-path switch 20b is arranged in the second power relay U2; the power supply input pin 21 in the second power relay U2 is respectively connected to the input end of the second double-path switch 20b and the second photovoltaic module 20a; the first power supply output pin 22 in the second power relay U2 is respectively connected to the normally open output end of the second double-path switch 20b and the positive pole of the first diode 10d; the second power supply output 23 pin in the second power relay U2 is respectively connected to the normally closed output end of the second double-path switch 20b and the power supply input end of the second maximum power point tracking controller 20c. The second double-path switch 20b in the second power relay U2 is connected to the second photovoltaic module 20a and the second maximum power point tracking controller 20c through the power supply input pin 21, the second power supply output pin 22 and the second power supply output pin 23. In the specific connection process, only the above-mentioned pins need to be connected.

[0046] In one embodiment, the instruction output terminal of the second maximum power point tracking controller 20c is connected to the instruction input pin 24 in the second power relay U2; the instruction feedback terminal of the second maximum power point tracking controller 20c is connected to the instruction feedback pin 25 in the second power relay U2; wherein, a second coil is provided in the second power relay U2, the input end of the second coil is connected to the instruction input pin 24 in the second power relay U2; the output end of the second coil is connected to the instruction feedback pin 25 in the second power relay U2; the second coil is used to switch the switching state of the second double-way switch 20b. The second coil directly controls the switching state of the second double-way switch. Generally speaking, the second coil is the control unit of the second double-way switch. The control instruction of the second coil is sent through the instruction output terminal of the second maximum power point tracking controller 20c and received by the instruction input pin 24 in the second power relay U2. The working state of the second coil is fed back to the instruction feedback terminal of the second maximum power point tracking controller 20c through the generated feedback instruction by using the instruction feedback pin 25 in the second power relay U2. The second coil in the second power relay U2 is connected to the second maximum power point tracking controller 20c through the instruction input pin 24 and the instruction feedback pin 25. In the specific connection process, only the above-mentioned pins need to be connected.

[0047] As Figure 4 shown, in one embodiment, a first power supply port is provided in the first maximum power point tracking controller 10c, and the first power supply port is connected to the first photovoltaic module 10a. A second power supply port is provided in the second maximum power point tracking controller 20c, and the second power supply port is connected to the second photovoltaic module 20a. The generated power of the first photovoltaic module 10a and the second photovoltaic module 20a is respectively transmitted to the power supply ports of the first maximum power point tracking controller 10c and the second maximum power point tracking controller 20c, and is used to trigger the power relays connected thereto. Generally speaking, the power supply of the first power relay U1 comes from the power supply of the first photovoltaic module 10a, and the power supply of the second power relay U2 comes from the power supply of the second photovoltaic module 20a.

[0048] As Figure 5Schematic diagram of the structure of the fifth type of photovoltaic cascaded circuit. In the specific process, the power relay uses the type of TE Connectivity relay 1-1393225-7, and the models of the first diode 10d and the second diode 10e are SBR10120CTL-13. This photovoltaic cascaded circuit has 1 main photovoltaic path 10 and 9 photovoltaic branches 20, a total of 10 paths. When the light is sufficient, the power generation efficiency of each photovoltaic module is relatively high, and the input power of the MPPT 1 controller and the MPPT2 controller is sufficient. At this time, both the main photovoltaic path 10 and each photovoltaic branch 20 can use their own MPPT controllers. The photovoltaic branch 20 transmits the power generation power of the second photovoltaic module 20a to the second maximum power point tracking controller 20c through its built-in second double-way switch 20b, and finally transmits it to the inverter through the second maximum power point tracking controller 20c. The main photovoltaic path 10 transmits the power generation power of the first photovoltaic module 10a to the first maximum power point tracking controller 10c through its built-in first double-way switch 10b, and finally transmits it to the inverter.

[0049] When the light is insufficient and the power generation efficiency of the photovoltaic module is lower than 10% of the rated power, the input power of the MPPT controller is insufficient. At this time, if the main photovoltaic path 10 and each photovoltaic branch 20 use the MPPT controller, it will bring relatively high small-power tracking conversion losses, affecting the overall tracking efficiency. At this time, each photovoltaic branch 20 switches its built-in second double-way switch 20b to the normally open path, so that the power generation power of the second photovoltaic module 20a is directly transmitted to the main photovoltaic path 10, and thus no longer input to the second maximum power point tracking controller 20c. The main photovoltaic path 10 also switches its built-in first double-way switch 10b to the normally open path, so that the power generation power of the first photovoltaic module 10a converges with the power generation power of the second photovoltaic module 20a and is transmitted to the first diode 10d, and after being rectified by the first diode 10d, it is centrally transmitted to the first maximum power point tracking controller 10c. At this time, the power generation power of the first photovoltaic module 10a in the main photovoltaic path 10 and the second photovoltaic modules 20a in all photovoltaic branches 20 are only input to the first maximum power point tracking controller 10c in the main photovoltaic path 10. By the method of combining ten paths into one path, the input power of the first maximum power point tracking controller 10c is increased, thereby reducing 80-90% of the small-power tracking conversion losses and improving the overall tracking efficiency.

[0050] It is worth mentioning that the above 10-in-1 method can be extended to 20-in-1, 30-in-1, etc. according to specific requirements.

[0051] As can be seen from the photovoltaic power generation cascade circuit provided by the embodiments of the present utility model, the photovoltaic power generation cascade circuit realizes the parallel switching of the MPPT controllers in the photovoltaic power generation branches through the dual-path switches arranged in the main photovoltaic power generation path and multiple mutually parallel photovoltaic power generation branches. When the power generation efficiency is relatively low, the generated power in the photovoltaic power generation branches can be integrally and parallelly input into the main photovoltaic power generation path, thereby increasing the input power of the MPPT controller in the main photovoltaic power generation path, reducing the conversion loss of small-power tracking, improving the overall tracking efficiency, and being conducive to improving the photovoltaic power generation efficiency.

[0052] An embodiment of the present utility model provides a photovoltaic power generation device, which includes the photovoltaic power generation cascade circuit mentioned in the above embodiments.

[0053] The photovoltaic power generation device utilizes the built-in photovoltaic power generation cascade circuit. Through the dual-path switches arranged in the main photovoltaic power generation path and multiple mutually parallel photovoltaic power generation branches, the parallel switching of the MPPT controllers in the photovoltaic power generation branches is realized. When the power generation efficiency is relatively low, the generated power in the photovoltaic power generation branches can be integrally and parallelly input into the main photovoltaic power generation path, thereby increasing the input power of the MPPT controller in the main photovoltaic power generation path, reducing the conversion loss of small-power tracking, improving the overall tracking efficiency, and being conducive to improving the photovoltaic power generation efficiency.

[0054] For the photovoltaic power generation cascade circuit in the photovoltaic power generation device provided by the embodiments of the present utility model, its implementation principle and the technical effects produced are the same as those of the foregoing embodiments of the photovoltaic power generation cascade circuit. For the sake of brief description, for the parts not mentioned in the device embodiments, reference may be made to the corresponding content in the foregoing embodiments.

[0055] In several embodiments provided in the present application, it should be understood that the disclosed systems and devices can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For another example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some communication interfaces. The indirect couplings or communication connections of devices or units can be in electrical, mechanical or other forms.

[0056] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place, or they can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0057] In addition, in each embodiment of the present utility model, each functional unit can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit.

[0058] If the above-mentioned functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium executable by a processor. Based on such an understanding, the technical solution of the present utility model, in essence, or the part that makes contributions to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of the present utility model. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs.

[0059] Finally, it should be noted that the above-mentioned embodiments are only specific implementation manners of the present utility model, used to illustrate the technical solutions of the present utility model, rather than limiting it. The protection scope of the present utility model is not limited thereto. Although the present utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that any person skilled in the art within the technical scope disclosed by the present utility model can still modify the technical solutions described in the foregoing embodiments, or can easily think of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes, or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present utility model, and should all be covered within the protection scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to the protection scope of the claims.

Claims

1. A photovoltaic power generation cascade circuit, characterized in that: The photovoltaic power generation cascade circuit comprises: a photovoltaic power generation main circuit and a plurality of photovoltaic power generation branches; Wherein, the photovoltaic power generation main path includes: a first photovoltaic component, a first dual-way switch, a first diode, a first maximum power point tracking controller and an inverter; the first photovoltaic component is connected to the input end of the first dual-way switch; the normally open output end of the first dual-way switch is connected to the positive electrode of the first diode; the cathode of the first diode and the normally closed output end of the first dual-way switch are both connected to the power supply input end of the first maximum power point tracking controller; the power supply output end of the first maximum power point tracking controller is connected to the inverter; The photovoltaic power generation branch includes: a second photovoltaic component, a second two-way switch, and a second maximum power point tracking controller; the second photovoltaic component is connected to the input end of the second two-way switch; the normally closed output end of the second two-way switch is connected to the power supply input end of the second maximum power point tracking controller; the normally open output end of the second two-way switch is connected to the positive electrode of the first diode in the photovoltaic power generation main circuit; the power supply output end of the second maximum power point tracking controller is connected to the inverter.

2. The photovoltaic power generation cascade circuit according to claim 1, characterized in that: The photovoltaic power generation main circuit also includes: a second diode; the anode of the second diode is connected to the normally closed output end of the first dual-way switch; the cathode of the second diode is connected to the power supply input end of the first maximum power point tracking controller.

3. The photovoltaic power generation cascade circuit according to claim 1, characterized in that: The first two-way switch and the second two-way switch are both two-way switches built into the power relay.

4. The photovoltaic power generation cascade circuit according to claim 3, characterized in that: The first dual-way switch is arranged in the first power relay; The power supply input pin in the first power relay is respectively connected to the input end of the first dual-way switch and the first photovoltaic component; The first power supply output pin in the first power relay is connected to the normally open output end of the first dual-way switch and the positive electrode of the first diode respectively; The second power supply output pin in the first power relay is respectively connected to the normally closed output end of the first dual-way switch and the power supply input end of the first maximum power point tracking controller.

5. The photovoltaic power generation cascade circuit according to claim 4, characterized in that: The command output terminal of the first maximum power point tracking controller is connected to the command input pin in the first power relay; the command feedback terminal of the first maximum power point tracking controller is connected to the command feedback pin in the first power relay; Among them, a first coil is provided in the first power relay, the input end of the first coil is connected to the command input pin in the first power relay; the output end of the first coil is connected to the command feedback pin in the first power relay; the first coil is used to switch the switching state of the first dual-way switch.

6. The photovoltaic power generation cascade circuit according to claim 3, characterized in that: The second dual-way switch is arranged in the second power relay; The power supply input pin in the second power relay is connected to the input end of the second dual-way switch and the second photovoltaic assembly respectively; The first power supply output pin in the second power relay is connected to the normally open output end of the second dual-way switch and the positive electrode of the first diode respectively; The second power supply output pin in the second power relay is respectively connected to the normally closed output end of the second dual-way switch and the power supply input end of the second maximum power point tracking controller.

7. The photovoltaic power generation cascade circuit according to claim 6, characterized in that: The command output terminal of the second maximum power point tracking controller is connected to the command input pin in the second power relay; the command feedback terminal of the second maximum power point tracking controller is connected to the command feedback pin in the second power relay; Among them, a second coil is provided in the second power relay, the input end of the second coil is connected to the instruction input pin in the second power relay; the output end of the second coil is connected to the instruction feedback pin in the second power relay; the second coil is used to switch the switching state of the second dual-way switch.

8. The photovoltaic power generation cascade circuit according to claim 1, characterized in that: The first maximum power point tracking controller is provided with a first power supply port, and the first power supply port is connected to the first photovoltaic component.

9. The photovoltaic power generation cascade circuit according to claim 1, characterized in that: The second maximum power point tracking controller is provided with a second power supply port, and the second power supply port is connected to the second photovoltaic assembly.

10. A photovoltaic power generation device, characterized in that: The photovoltaic power generation equipment comprises the photovoltaic power generation cascade circuit as described in any one of claims 1 to 9 above.

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