Optical storage direct current coupling system

Abstract

The utility model belongs to the technical field of energy storage, and provides an optical storage direct current coupling system, which comprises a photovoltaic module, a photovoltaic charger, a battery inverter, a load, a rectifier cabinet, a switching cabinet, a power grid and a generator, and is characterized in that the photovoltaic charger is connected with the photovoltaic module; the battery inverter is connected with the photovoltaic charger; the load is connected with the battery inverter; the rectifier cabinet is respectively connected with the battery inverter and the photovoltaic charger; the switching cabinet is connected with the rectifier cabinet; the power grid is connected with the switching cabinet; and the generator is connected with the switching cabinet. According to the invention, the problems of load voltage fluctuation caused by switching the system from the grid-connected state to the off-grid state and unstable load voltage caused by unstable power grid are solved.

Description

Technical Field

[0001] This application belongs to the technical field of energy storage, and specifically relates to a photovoltaic-storage DC coupling system. Background Art

[0002] In the currently commonly used AC coupling energy storage system, when the system load power is large, or there are many inductive loads, such as motors, water pumps, compressors, air compressors, etc., in the grid connection and disconnection switching process, there is an easy phenomenon of unstable AC voltage after switching, resulting in abnormal operation or power outage of the load. And when applied to a grid environment with frequent grid voltage fluctuations, it is more likely to cause unstable operation of the load. Summary of the Utility Model

[0003] In order to overcome the above-mentioned drawbacks in the prior art, the purpose of this application is to provide a photovoltaic-storage DC coupling system to solve the problems of load voltage fluctuations caused by the system switching from the grid-connected state to the off-grid state, and load voltage instability caused by grid instability.

[0004] The technical means adopted by this application to solve the above technical problems is as follows:

[0005] This application provides a photovoltaic-storage DC coupling system, including:

[0006] Photovoltaic modules;

[0007] A photovoltaic charger, which is connected to the photovoltaic modules;

[0008] A battery inverter, which is connected to the photovoltaic charger;

[0009] A load, which is connected to the battery inverter;

[0010] A rectifier cabinet, which is respectively connected to the battery inverter and the photovoltaic charger;

[0011] A switching cabinet, which is connected to the rectifier cabinet;

[0012] A power grid, which is connected to the switching cabinet;

[0013] A generator, which is connected to the switching cabinet.

[0014] Preferably, it further includes a battery pack, which is respectively connected to the photovoltaic charger, the battery inverter, and the rectifier cabinet.

[0015] Preferably, the battery pack is a lithium battery pack.

[0016] Preferably, the load is at least one of an air conditioner, a water pump, a motor, and a lighting device.

[0017] Preferably, the photovoltaic module is a solar panel.

[0018] Compared with the prior art, the optical storage DC coupling system of the present application has the following beneficial effects:

[0019] 1. The battery inverter of the present application operates with a load in a pure off-grid mode, there is no voltage fluctuation problem caused by the switching between grid-connected and off-grid modes, reducing the voltage fluctuation caused by the switching, and enabling the load to operate more stably.

[0020] 2. The battery inverter of the present application operates in a pure off-grid mode, and the voltage is always controlled by the battery inverter for constant voltage output. There is no problem of load voltage fluctuation caused by grid voltage fluctuation. In the traditional AC coupling, when the battery inverter is in the grid-connected mode, the output voltage will follow the grid voltage. When the grid voltage fluctuates, as long as it does not exceed the upper and lower limits, the battery inverter will follow the fluctuation. For the load, frequent fluctuations have a greater impact on stable operation, such as the lighting device flickering.

[0021] 3. The grid connection of the present application is different from the traditional AC coupling scheme and is not directly connected to the load AC bus in the grid-connected mode. In the traditional AC coupling scheme, when the load power suddenly increases or decreases, the grid first needs to bear the large power fluctuation. The grid connection of the present application is on the switching cabinet and is then connected to the rectifier cabinet through the switching cabinet. The power of the rectifier cabinet is controllable, and there will be no impact power exceeding the range for the grid.

[0022] 4. The connection of the generator of the present application is different from the traditional AC coupling scheme and is not directly connected to the load AC bus in the grid-connected diesel engine mode. In the traditional AC coupling scheme, when the load power suddenly increases or decreases, the generator first needs to bear the large power fluctuation. The generator of the present application is connected to the switching cabinet and is then connected to the rectifier cabinet through the switching cabinet. The power of the rectifier cabinet is controllable, and there will be no impact power exceeding the range for the generator.

[0023] 5. The present application has an anti-backflow function. In the traditional AC coupling, in the grid-connected mode, since the grid is connected to the load AC bus, when the load power fluctuates, there will be a short-time backflow to the grid because the battery inverter needs a certain time to control and reduce the power. The power of the rectifier cabinet of the present application is not affected by the load power fluctuation and can completely prevent backflow to the grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 This is a schematic structural diagram of the optical storage DC coupling system of the present application. Specific embodiments

[0026] In order to more clearly understand the above objects, features, and advantages of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other. In the following description, many specific details are set forth in order to fully understand the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0027] It should be noted that: Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention in this specification are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. Similar reference numerals and letters in the following drawings represent similar items. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present application, the terms "first", "second", etc. are only used for distinguishing descriptions, and cannot be understood as indicating or implying relative importance.

[0028] As Figure 1 shown, in this embodiment, an optical storage DC coupling system is provided, including a photovoltaic module, a photovoltaic charger, a battery inverter, a load, a rectifier cabinet, a switching cabinet, a power grid, and a generator. The photovoltaic charger is connected to the photovoltaic module; the battery inverter is connected to the photovoltaic charger; the load is connected to the battery inverter; the rectifier cabinet is respectively connected to the battery inverter and the photovoltaic charger; the switching cabinet is connected to the rectifier cabinet; the power grid is connected to the switching cabinet; the generator is connected to the switching cabinet.

[0029] In some preferred embodiments of the present application, a battery pack is further included, and the battery pack is respectively connected to the photovoltaic charger, the battery inverter, and the rectifier cabinet.

[0030] In some preferred embodiments of the present application, the battery pack is a lithium battery pack.

[0031] In some preferred embodiments of the present application, the load is at least one of an air conditioner, a water pump, a motor, and a lighting device.

[0032] In some preferred embodiments of the present application, the photovoltaic module is a solar panel.

[0033] Compared with the prior art, the photovoltaic-storage DC coupling system of the present application has the following beneficial effects:

[0034] 1. The battery inverter of the present application operates with a load in a pure off-grid mode, eliminating the voltage fluctuation problem caused by the switching between grid-connected and off-grid modes, reducing the voltage fluctuation caused by the switching, and enabling the load to operate more stably.

[0035] 2. The battery inverter of the present application operates in a pure off-grid mode, and the voltage is always controlled by the battery inverter for constant voltage output, eliminating the load voltage fluctuation problem caused by grid voltage fluctuations. In the traditional AC coupling, when the battery inverter is in the grid-connected mode, the output voltage will follow the grid voltage. When the grid voltage fluctuates, as long as it does not exceed the upper and lower limits, the battery inverter will follow the fluctuation. For the load, frequent fluctuations have a greater impact on stable operation, such as the lighting equipment flickering.

[0036] 3. The grid connection of the present application is different from the traditional AC coupling scheme and is not directly connected to the load AC bus in the grid-connected mode. In the traditional AC coupling scheme, when the load power suddenly increases or decreases, the grid first needs to bear the large power fluctuation. The grid connection of the present application is on the switching cabinet and is then connected to the rectifier cabinet through the switching cabinet. The power of the rectifier cabinet is controllable, and there will be no impact power exceeding the range on the grid.

[0037] 4. The connection of the generator of the present application is different from the traditional AC coupling scheme and is not directly connected to the load AC bus in the grid-connected diesel engine mode. In the traditional AC coupling scheme, when the load power suddenly increases or decreases, the generator first needs to bear the large power fluctuation. The generator of the present application is connected to the switching cabinet and is then connected to the rectifier cabinet through the switching cabinet. The power of the rectifier cabinet is controllable, and there will be no impact power exceeding the range on the generator.

[0038] 5. The present application has an anti-backflow function. In the traditional AC coupling, in the grid-connected mode, since the grid is connected to the load AC bus, when the load power fluctuates, there will be a short-time backflow to the grid because the battery inverter needs a certain time to control and reduce the power. The power of the rectifier cabinet of the present application is not affected by the load power fluctuation and can completely prevent backflow to the grid.

[0039] As described above, this is only the specific implementation manner of the present application and is not used to limit the protection scope of the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application. Any person skilled in the art within the technical scope disclosed by the present application can easily think of changes or replacements, which should also be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

[0040] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the existence of additional identical elements in the process, method, article or device comprising the said element.

Claims

1. A photovoltaic energy storage DC coupling system, characterized in that: include: Photovoltaic panels; A photovoltaic charger connected to the photovoltaic assembly; A battery inverter connected to the photovoltaic charger; a load connected to the battery inverter; A rectifier cabinet, which is connected to the battery inverter and the photovoltaic charger respectively; A switching cabinet, the switching cabinet is connected to the rectifier cabinet; A power grid, the power grid being connected to the switching cabinet; A generator is connected to the switching cabinet.

2. The photovoltaic energy storage DC coupling system according to claim 1, characterized in that: It also includes a battery pack, which is respectively connected to the photovoltaic charger, the battery inverter and the rectifier cabinet.

3. The photovoltaic energy storage DC coupling system according to claim 2, characterized in that: The battery pack is a lithium battery pack.

4. The photovoltaic energy storage DC coupling system according to claim 1, characterized in that: The load is at least one of an air conditioner, a water pump, a motor, and a lighting device.

5. The photovoltaic energy storage DC coupling system according to claim 1, characterized in that: The photovoltaic component is a solar cell panel.

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