Photovoltaic power generation system
By combining a battery structure with parallel high-voltage battery units and series low-voltage battery units with a power optimizer, the high cost and compatibility issues of four-terminal tandem photovoltaic modules in photovoltaic power generation systems are solved, achieving cost savings and efficiency improvements.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-16
- Publication Date
- 2026-04-10
AI Technical Summary
The mismatch of electrical parameters between cells in four-terminal tandem photovoltaic modules in photovoltaic power generation systems requires the configuration of independent junction boxes and power generation circuits, which increases costs and is incompatible with the existing standardized circuit topology of power plants. The optical parasitic loss and the complex system integration requirements of multi-MPPT controllers also restrict their large-scale application.
The battery structure adopts parallel high-voltage battery units and series low-voltage battery units, combined with a power optimizer to form a stable MPPT output, reducing the number of junction boxes and power generation circuits, and is compatible with the existing power station circuit topology.
It significantly reduces costs, improves system efficiency and feasibility for large-scale deployment, and achieves compatibility with existing power plant circuit topologies.
Smart Images
Figure CN224111589U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to photovoltaic cell technical field especially relates to a photovoltaic power generation system. BACKGROUND
[0002] Four-terminal laminated photovoltaic module realizes wide spectrum absorption and heat loss inhibition through vertical integration of heterostructure band gap materials (such as perovskite / crystalline silicon) and four-terminal independent circuit architecture, and the theoretical efficiency can break through the upper limit of 40%. Four-terminal laminated photovoltaic module avoids the current matching constraint of traditional laminated cell by means of the electrical decoupling characteristics of sub-cell, and can significantly improve the design freedom and thermal distribution uniformity. However, when the four-terminal laminated photovoltaic module is applied in the photovoltaic power generation system, the electrical parameter mismatch problem (such as the voltage-current characteristic difference of perovskite cell and crystalline silicon cell) between the sub-cells of the module requires that each module be configured with an independent junction box and a power generation circuit (such as shown in FIG. Figure 1 The optical parasitic loss (such as transparent electrode absorption, interface reflection, etc.) caused by the multi-layer stacking in the four-terminal laminated photovoltaic module and the complex system integration requirements of multiple MPPT controllers will further restrict its large-scale application in the photovoltaic power generation system. SUMMARY
[0003] Therefore, it is necessary to provide a photovoltaic power generation system for solving the problem that each module needs to be configured with an independent junction box and a power generation circuit when the four-terminal laminated photovoltaic module is applied in the photovoltaic power generation system.
[0004] A photovoltaic power generation system includes a plurality of four-terminal laminated photovoltaic modules, each of which includes a first cell unit and a second cell unit; the first cell units in the plurality of four-terminal laminated photovoltaic modules are connected in parallel, and the second cell units in the plurality of four-terminal laminated photovoltaic modules are connected in series.
[0005] The above-mentioned photovoltaic power generation system does not need to configure an independent junction box and a power generation circuit in each four-terminal laminated photovoltaic module, which greatly saves the cost.
[0006] The four-terminal laminated photovoltaic module refers to a cell structure in which two sub-cells are connected in parallel and optically coupled, but remain independent in current.
[0007] In one embodiment, the first cell unit is a high-voltage cell unit, and the second cell unit is a low-voltage cell unit.
[0008] In one embodiment, the high-voltage cell unit and the low-voltage cell unit are both independent power generation units.
[0009] In one embodiment, the number of the four-terminal laminated photovoltaic modules is N, the N is less than the open voltage of the first cell unit / the open voltage of the second cell unit, the N is greater than or equal to 2, and the N is an integer.
[0010] In one embodiment, the photovoltaic power generation system further comprises at least one bypass diode, and when the N is greater than or equal to 3, the bypass diode is connected in parallel to the second cell unit of the second to (N-1)th four-terminal laminated photovoltaic module.
[0011] In one embodiment, the photovoltaic power generation system further comprises at least one power optimizer, and the first cell unit of a plurality of the four-terminal laminated photovoltaic modules is connected in parallel to the first power optimizer.
[0012] In one embodiment, the photovoltaic power generation system further comprises at least one power optimizer, and the series circuit formed by the second cell units is connected in parallel to the second power optimizer.
[0013] In one embodiment, the parallel circuit formed by the first cell units and the series circuit formed by the second cell units are connected in parallel to the junction box.
[0014] The photovoltaic power generation system of the utility model, a plurality of four-terminal laminated photovoltaic modules are combined into one power generation system, high-voltage cell units are connected in parallel, low-voltage cell units are connected in series to match the voltage with each other and cooperate with a power optimizer to form stable MPPT output, and finally output power through one junction box, thereby reducing the number of junction boxes and power generation circuits in the power generation system, greatly saving cost, and also being compatible with the standardized circuit topology of existing power stations.
[0015] In one embodiment, the power optimizer comprises at least one of a Buck power optimizer, a Boost power optimizer, a Buck-Boost power optimizer, a resonant LLC power optimizer, an SRC power optimizer and a DC-DC converter. The power optimizer, also called a photovoltaic power optimizer or a component power optimizer, adopts a unique software algorithm to track the maximum power point of a single component in real time, and users can select different types of power optimizers according to the actual operation of the photovoltaic system to solve the problem of reduced power generation of the photovoltaic system caused by shadow shielding, component orientation difference or inconsistent component attenuation, realize maximum power output and online monitoring of a single component, and improve system efficiency.
[0016] In one of the embodiments, the first battery cell comprises at least one of perovskite photovoltaic cell, chromium telluride battery, copper indium gallium selenide battery, and crystalline silicon battery, and the second battery cell comprises at least one of perovskite photovoltaic cell, chromium telluride battery, copper indium gallium selenide battery, and crystalline silicon battery.
[0017] In one of the embodiments, the first battery cell is a perovskite photovoltaic cell, and the second battery cell is a crystalline silicon battery.
[0018] In one of the embodiments, the four-terminal laminated photovoltaic module comprises, from top to bottom, a substrate, the first battery cell, a first encapsulation layer, the second battery cell, a second encapsulation layer, and a protective layer.
[0019] The utility model further provides a power station, including the photovoltaic power generation system of any one of the above.
[0020] Compared with the prior art, the utility model has the following beneficial effects:
[0021] The photovoltaic power generation system of the utility model does not need to configure independent junction box and power generation loop in each four-terminal laminated photovoltaic module, greatly saves the cost. The photovoltaic power generation system of the utility model collects multiple four-terminal laminated photovoltaic modules into one power generation system, high-voltage battery cells are connected in parallel, low-voltage battery cells are connected in series to match the voltage with each other and cooperate power optimizer to form stable MPPT output, finally outputs power with one junction box, reduces the number of junction box and power generation loop in the power generation system, greatly saves the cost, and can also be compatible with the standardization circuit topology structure of the existing power station. BRIEF DESCRIPTION OF DRAWINGS
[0022] Figure 1 It is a traditional connection mode schematic diagram of four-terminal laminated photovoltaic module in photovoltaic power generation system;
[0023] Figure 2 It is a structure schematic diagram of photovoltaic power generation system in embodiment 1;
[0024] Figure 3 It is a structure schematic diagram of photovoltaic power generation system in embodiment 2-4.
[0025] Mark explanation: 1, four-terminal laminated photovoltaic module;11, first battery cell;12, second battery cell;21, first power optimizer;22, second power optimizer;3, bypass diode;4, junction box. DETAILED DESCRIPTION
[0026] For the purpose of facilitating the understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The preferred embodiments of the present application are shown in the drawings. However, the present application can be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the present application will be thorough and complete, and will fully convey the scope of the application to those skilled in the art.
[0027] It should be noted that when an element is referred to as being "fixed" to another element, it can be directly on the other element or intervening elements can also be present. When an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements can also be present. In addition, the terms "central", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, as used herein, refer to the orientation or position of the apparatus or element shown in the drawings, and are used only for convenience in describing the present application and its embodiments, and are not intended to indicate or imply that a specific orientation, configuration, or arrangement of the apparatus or element is required for the proper working of the present application, and therefore should not be construed as limiting the present application. The terms "first", "second", "third", etc. are used only for descriptive purposes and should not be construed as indicating or implying relative importance.
[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.
[0029] Embodiment 1
[0030] A photovoltaic power generation system, as shown in Figure 2 includes a plurality of four-terminal laminated photovoltaic modules 1 and a plurality of power optimizers.
[0031] The power optimizer includes a first power optimizer 21 and a second power optimizer 22, and the power optimizer includes at least one of a Buck power optimizer, a Boost power optimizer, a Buck-Boost power optimizer, a resonant LLC power optimizer, an SRC power optimizer, and a DC-DC converter.
[0032] Each four-terminal laminated photovoltaic module 1 includes a first cell unit 11 and a second cell unit 12, the first cell unit 11 is a high-voltage cell unit, and the second cell unit 12 is a low-voltage cell unit; the high-voltage cell unit and the low-voltage cell unit are both independent power generation units, and the two are laminated. The first cell unit 11 includes at least one of a perovskite photovoltaic cell, a chromium telluride cell, a copper indium gallium selenide cell, and a crystalline silicon cell, and the second cell unit 12 includes at least one of a perovskite photovoltaic cell, a chromium telluride cell, a copper indium gallium selenide cell, and a crystalline silicon cell.
[0033] The first cell units 11 in the plurality of four-terminal laminated photovoltaic modules 1 are connected in parallel through wires and a first power optimizer 21; the second cell units 12 in the plurality of four-terminal laminated photovoltaic modules 1 are connected in series through wires, and the series circuit formed by the second cell units 12 is connected in parallel with a second power optimizer 22. The parallel circuit formed by the first cell units 11 and the series circuit formed by the second cell units 12 are connected in parallel and then connected to the junction box 4.
[0034] The number N of the plurality of four-terminal laminated photovoltaic modules 1 is less than the open voltage of the first cell unit 11 / the open voltage of the second cell unit 12, N≥2 and is an integer (for example: the open voltage of the first cell unit 11 is 273V, the open voltage of the second cell unit 12 is 48V, 273 / 48=5.68, N≤5.68, so the number N of the four-terminal laminated photovoltaic modules 1 can be 5 or 4 or 3 or 2).
[0035] When N≥3, the second cell unit 12 on the second to (N-1) four-terminal laminated photovoltaic module 1 is connected in parallel with a bypass diode 3.
[0036] The above scheme can realize dynamic voltage adaptation and global MPPT optimization by using hybrid series-parallel topology architecture (high-voltage parallel expansion and low-voltage series expansion) for the high-voltage cell unit and the low-voltage cell unit in the four-terminal laminated photovoltaic module 1, and combining a power optimizer (such as a DC-DC power electronic compensation control device). Through active voltage-current collaborative matching between sub-cell units, the scheme reduces the hetero-material mismatch loss, and uses a centralized power electronic conversion module to replace the traditional dispersed power generation circuit, thereby constructing an integrated single junction box 4 output architecture, thereby significantly reducing the number of independent junction boxes 4 and the complexity of cables required by the four-terminal laminated photovoltaic module 1. At the same time, the output characteristics (such as voltage / current range) of the photovoltaic power generation system can be compatible with the standard inverter and circuit topology of the existing power station, avoiding system-level modification, reducing BOS (system balance cost), and improving the feasibility of large-scale deployment.
[0037] Embodiment 2
[0038] A photovoltaic power generation system, such as Figure 3As shown, it comprises 5 four-terminal laminated photovoltaic modules 1 and 2 power optimizers; the power optimizers are respectively a first power optimizer 21 and a second power optimizer 22.
[0039] Each four-terminal laminated photovoltaic module 1 comprises a first cell unit 11 and a second cell unit 12, the first cell unit 11 is a high-voltage cell unit, and the second cell unit 12 is a low-voltage cell unit; both the high-voltage cell unit and the low-voltage cell unit are independent power generation units, and the two are laminated.
[0040] The first cell units 11 in the 5 four-terminal laminated photovoltaic modules 1 are connected in parallel with the first power optimizer 21 through wires; the second cell units 12 in the 5 four-terminal laminated photovoltaic modules 1 are connected in series with each other, and the series circuit formed by the second cell units 12 is connected in parallel with the second power optimizer 22. A bypass diode 3 is connected in parallel on the second cell unit 12 of the second to fourth four-terminal laminated photovoltaic modules 1. The parallel circuit formed by the first cell units 11 is connected in parallel with the series circuit formed by the second cell units 12, and then connected to the junction box 4.
[0041] The structure of the four-terminal laminated photovoltaic module 1 comprises a substrate, a first cell unit 11, a first encapsulation layer, a second cell unit 12, a second encapsulation layer, and a protective layer, which are sequentially and laminatedly arranged from top to bottom. The substrate is a glass plate, the first cell unit 11 is a perovskite photovoltaic cell, the first encapsulation layer is a polyolefin elastomer layer, the second cell unit 12 is an HJT crystalline silicon cell, the second encapsulation layer is a polyolefin elastomer layer, and the protective layer is a glass plate.
[0042] The perovskite photovoltaic cell comprises a 5nm-thick SAM hole transport layer, a perovskite light-absorbing layer (with a band gap of 1.6eV), a 60nm-thick C 60 electron transport layer, a 30nm-thick SnO x transport layer, and a 300nm-thick TCO electrode layer, which are sequentially and laminatedly arranged.
[0043] Example 3
[0044] A photovoltaic power generation system, the structure of which is basically the same as that of Example 2, except that the structure of the four-terminal laminated photovoltaic module 1 comprises a substrate, a first cell unit 11, a first encapsulation layer, a second cell unit 12, a second encapsulation layer, and a protective layer, which are sequentially and laminatedly arranged from top to bottom. The substrate is a flexible conductive glass, the first cell unit 11 is a perovskite photovoltaic cell, the first encapsulation layer is an ethylene-vinyl acetate copolymer layer, the second cell unit 12 is a TopCon crystalline silicon cell, the second encapsulation layer is an ethylene-vinyl acetate copolymer layer, and the protective layer is a water vapor barrier film.
[0045] The perovskite photovoltaic cell comprises a 5nm-thick SAM hole transport layer, a perovskite light-absorbing layer (with a band gap of 1.6eV), a 20nm-thick C60 electron transport layer, 30 nm of SnO x transport layer and 100 nm of TCO electrode layer.
[0046] Example 4
[0047] A photovoltaic power generation system, the structure is basically the same as that of example 2, the difference is that: the structure of the four-terminal laminated photovoltaic module 1 comprises a substrate, a first cell unit 11, a first encapsulation layer, a second cell unit 12, a second encapsulation layer and a protective layer which are sequentially stacked from top to bottom. The substrate is a polyethylene terephthalate layer, the first cell unit 11 is a perovskite photovoltaic cell, the first encapsulation layer is a thermoplastic polyolefin layer, the second cell unit 12 is a BC crystalline silicon cell, the second encapsulation layer is a thermoplastic polyolefin layer, and the protective layer is a water vapor barrier film.
[0048] The perovskite photovoltaic cell comprises a 5nm thick SAM hole transport layer, a perovskite light absorbing layer (with a band gap of 1.6eV), 30nm of C 60 electron transport layer, 30 nm of SnO x transport layer and 200 nm of TCO electrode layer.
[0049] Experimental example
[0050] The electrical performance changes of the parallel circuit of the first cell unit 11, the series circuit of the second cell unit 12 and the four-terminal laminated photovoltaic module circuit obtained by connecting the above parallel circuit and series circuit in parallel in examples 2-4 are detected using a steady-state solar simulator, and the detection results are shown in Table 1.
[0051]
[0052] Each technical feature of the above-described embodiments can be combined arbitrarily, and in order to make the description simple, not all possible combinations of each technical feature in the above-described embodiments are described, however, as long as the combination of these technical features does not exist contradictory, it should be considered as the scope of the description.
[0053] The above-described embodiments only express several implementation manners of the present application, the description is more specific and detailed, but it should not be understood as a limitation on the scope of the application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of the present application patent should be subject to the appended claims.
Claims
1. A photovoltaic power system, characterized by, The application relates to a four-terminal laminated photovoltaic module, comprising a plurality of four-terminal laminated photovoltaic components, each of which comprises a first cell unit and a second cell unit; the first cell units of the plurality of four-terminal laminated photovoltaic components are connected in parallel, and the second cell units of the plurality of four-terminal laminated photovoltaic components are connected in series.
2. The photovoltaic power system of claim 1, wherein, The first cell unit is a high-voltage cell unit, and the second cell unit is a low-voltage cell unit.
3. The photovoltaic power system of claim 2, wherein, The high-voltage cell unit and the low-voltage cell unit are both independent power generation units.
4. The photovoltaic power system of claim 2, wherein, The number of the four-terminal laminated photovoltaic components is N, the N is less than the open voltage of the first cell unit / the open voltage of the second cell unit, the N is greater than or equal to 2, and the N is an integer.
5. The photovoltaic power system of claim 4, wherein, At least one bypass diode is further included; when the N is greater than or equal to 3, the bypass diode is connected in parallel to the second cell unit of the second to (N-1)-th four-terminal laminated photovoltaic component.
6. The photovoltaic power system of claim 1, wherein, At least one power optimizer is further included, the power optimizer comprises a first power optimizer, and the first cell units of the plurality of four-terminal laminated photovoltaic components are connected in parallel to the first power optimizer.
7. The photovoltaic power system of claim 1, wherein, At least one power optimizer is further included, the power optimizer comprises a second power optimizer, and the series circuit formed by the second cell units is connected in parallel to the second power optimizer.
8. The photovoltaic power system according to any of claims 6 or 7, characterized in that, The power optimizer comprises at least one of a Buck power optimizer, a Boost power optimizer, a Buck-Boost power optimizer, a resonant LLC power optimizer, an SRC power optimizer and a DC-DC converter.
9. The photovoltaic power system of claim 1, wherein, The first cell unit comprises at least one of a perovskite photovoltaic cell, a chromium telluride cell, a copper indium gallium selenide cell and a crystalline silicon cell, and the second cell unit comprises at least one of a perovskite photovoltaic cell, a chromium telluride cell, a copper indium gallium selenide cell and a crystalline silicon cell.
10. The photovoltaic power system of claim 1, wherein, The four-terminal laminated photovoltaic component comprises, from top to bottom, a substrate, the first cell unit, a first encapsulation layer, the second cell unit, a second encapsulation layer and a protective layer.