Method and device for evaluating output power of double-sided photovoltaic module in shadow shielding scene

Abstract

The embodiment of the invention discloses a method and device for evaluating the output power of a double-sided photovoltaic module in a shadow shielding scene, and is applied to the technical field of double-sided photovoltaic modules. The method comprises the following steps: firstly, respectively calculating five parameters of a shadow area and a non-shadow area of the front / rear side of the battery under a standard test condition according to a shadow area percentage and five parameters of the front / rear side of the double-sided photovoltaic battery under the standard test condition; secondly, respectively calculating five parameters of shadow and non-shadow areas on the front / rear side of the battery in a shadow shielding scene according to the radiation shielding proportion; a double-current-source model of the double-sided photovoltaic cell in the shadow shielding scene is constructed again, and five parameters of the front / rear side of the photovoltaic cell in the shadow shielding scene are calculated respectively; and finally, constructing a parallel equivalent circuit model, calculating five target parameters of the single double-sided photovoltaic cell in the shadow shielding scene, and sequentially calculating I-V characteristic equations of the cell, the cell string and the module based on the five target parameters, thereby realizing accurate evaluation of the output power of the double-sided photovoltaic module in the shadow shielding scene.

Description

Technical Field

[0001] The present application relates to the technical field of bifacial photovoltaic modules, and in particular to a method and device for evaluating the output power of a bifacial photovoltaic module in a shadow-shading scenario. Background Art

[0002] Bifacial photovoltaic modules can absorb solar energy from both the front and back sides of the modules to generate electricity. They have attracted much attention due to their lower levelized cost of energy (LCOE). However, in actual operation, mutual shielding between modules will lead to uneven radiation distribution on the front and back sides of bifacial photovoltaic modules. Under the aforementioned uneven radiation conditions, electrical mismatch will occur between the cells of the module, resulting in a decrease in the total output power of the module.

[0003] Existing photovoltaic power generation models take into account the shadow blocking scenario, see Figure 1 , (a) is a type of shadow shielding in which the radiation intensity of the same cell in the photovoltaic module is uniformly distributed, but the radiation intensity between each cell is uneven. (b) is a type of shadow shielding in which the radiation intensity of different areas in the same cell is different. For the shadow shielding type shown in (b), the existing photovoltaic power generation model usually uses the area weighted average method to calculate the total radiation of each area of ​​the same cell, ignoring the electrical mismatch problem between the shadow area and the non-shadow area of ​​the cell, thereby causing simulation errors. In addition, existing models generally use a constant bifacial coefficient to measure the ratio of the power generation performance of the rear side of the bifacial photovoltaic module to the power generation performance of the front side, and calculate the dynamic output power of the bifacial photovoltaic module based on this. However, when the radiation conditions on the front / rear side of the bifacial photovoltaic module change or there is a Figure 1 When complex shadows are shown, the power generation performance of the front / rear side will change, and the traditional constant bifacial coefficient method is no longer applicable.

[0004] In summary, the applicable scenarios of existing models are limited, especially it is difficult to simulate the output power of bifacial modules under the condition of partial shadows on the front and back sides. In addition, the existing models fail to fully consider the impact of radiation intensity and shadows on the power generation performance of the front and back sides of bifacial modules, resulting in the inability to accurately simulate the dynamic output power of bifacial modules, thus causing simulation errors. Summary of the invention

[0005] In view of this, the present application provides a method and device for evaluating the output power of a bifacial photovoltaic module in a shadow-blocking scenario, which can accurately evaluate the dynamic output power of a bifacial photovoltaic module.

[0006] To solve the above problems, the technical solutions provided by this application are as follows:

[0007] In a first aspect, an embodiment of the present application provides a method for evaluating the output power of a bifacial photovoltaic module in a shadow-blocking scene, wherein the bifacial photovoltaic module is formed by connecting a plurality of single bifacial photovoltaic cells, and the evaluation method comprises:

[0008] Calculate five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, the five parameters including photocurrent, dark saturation current of the diode, series resistance, parallel resistance and diode thermal voltage;

[0009] Determine the shadow area percentage and radiation shielding ratio of a single bifacial photovoltaic cell, wherein the shadow area percentage and the radiation shielding ratio are used to characterize the shadow shielding condition of the single bifacial photovoltaic cell;

[0010] Calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-shading scenario according to a pre-constructed dual current source model of the bifacial photovoltaic cell in a shadow-shading scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio;

[0011] Calculate the target five parameters of a single bifacial photovoltaic cell in a shadow-shading scenario according to the pre-constructed bifacial photovoltaic cell parallel equivalent circuit model and the five parameters of the front / rear side of the single bifacial photovoltaic cell in a shadow-shading scenario;

[0012] Based on the target five parameters of the single bifacial photovoltaic cell in the shadow-blocking scenario, the IV characteristic equations of the single bifacial photovoltaic cell, the bifacial photovoltaic cell string and the bifacial photovoltaic module are calculated in turn to determine the output power of the bifacial photovoltaic module in the shadow-blocking scenario.

[0013] In a possible implementation, the calculation of five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions includes:

[0014] Obtaining front-side rated parameters, rear-side rated parameters and internal circuit characteristics of the bifacial photovoltaic module;

[0015] Calculating five front-side parameters of a bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the front-side rated parameters;

[0016] Calculating five parameters of the rear side of the bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the rear side rated parameters;

[0017] Calculating five parameters of the front side of the single bifacial photovoltaic cell under standard test conditions based on the five parameters of the front side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component;

[0018] The five parameters of the rear side of the single bifacial photovoltaic cell under standard test conditions are calculated based on the five parameters of the rear side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component.

[0019] In a possible implementation, determining the shadow area percentage and radiation shielding ratio of a single bifacial photovoltaic cell includes:

[0020] Obtain the shadow area, radiation intensity of the shadow area, non-shadow area, and radiation intensity of the non-shadow area of ​​a single bifacial photovoltaic cell in a shadow-blocking scenario;

[0021] Determining the shadow area percentage based on the shadow area and the non-shadow area;

[0022] The radiation shielding ratio is determined based on the shadow area radiation intensity and the non-shadow area radiation intensity.

[0023] In a possible implementation, the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-blocking scenario are calculated based on a pre-constructed dual current source model of the bifacial photovoltaic cell in a shadow-blocking scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio, including:

[0024] According to the shadow area percentage and the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under standard test conditions are calculated respectively;

[0025] Calculate the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shielding scene according to the radiation shielding ratio and the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under the standard test conditions;

[0026] In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the front shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the front non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the front side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated;

[0027] In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the rear shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the rear side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated.

[0028] In a possible implementation, based on the target five parameters of the single bifacial photovoltaic cell in the shadow-shading scene, IV characteristic equations of the single bifacial photovoltaic cell, the bifacial photovoltaic cell string and the bifacial photovoltaic module are calculated in sequence to determine the output power of the bifacial photovoltaic module in the shadow-shading scene, including:

[0029] Using the target five parameters of the single bifacial photovoltaic cell in the shadow shading scene, an IV characteristic equation of the single bifacial photovoltaic cell in the shadow shading scene is calculated;

[0030] Based on the IV characteristic equation of the single bifacial photovoltaic cell, the IV characteristic equation of the bifacial photovoltaic cell string in the shadow shading scene is calculated;

[0031] Based on the IV characteristic equation of the bifacial photovoltaic cell string, the IV characteristic equation of the bifacial photovoltaic module in the shadow shading scene is calculated;

[0032] The output power of the bifacial photovoltaic module in a shadow-shading scenario is determined based on the IV characteristic equation of the bifacial photovoltaic module.

[0033] In a second aspect, an embodiment of the present application provides an evaluation device for the output power of a bifacial photovoltaic module in a shadow-blocking scene, wherein the bifacial photovoltaic module is formed by connecting a plurality of single bifacial photovoltaic cells, and the evaluation device comprises:

[0034] A first calculation module is used to calculate five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, wherein the five parameters include photocurrent, dark saturation current of the diode, series resistance, parallel resistance and diode thermal voltage;

[0035] A first determination module is used to determine the shadow area percentage and radiation shielding ratio of a single bifacial photovoltaic cell, wherein the shadow area percentage and the radiation shielding ratio are used to characterize the shadow shielding condition of the single bifacial photovoltaic cell;

[0036] The second calculation module is used to calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-blocking scenario according to a pre-constructed dual current source model of the bifacial photovoltaic cell in a shadow-blocking scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio;

[0037] A third calculation module is used to calculate the target five parameters of a single bifacial photovoltaic cell in a shadow-shading scenario according to a pre-constructed bifacial photovoltaic cell parallel equivalent circuit model and the five parameters of the front / rear side of the single bifacial photovoltaic cell in the shadow-shading scenario;

[0038] The second determination module is used to calculate the IV characteristic equations of the single bifacial photovoltaic cell, the bifacial photovoltaic cell string and the bifacial photovoltaic module in sequence based on the target five parameters of the single bifacial photovoltaic cell in the shadow shading scenario, and determine the output power of the bifacial photovoltaic module in the shadow shading scenario.

[0039] In a possible implementation, the first calculation module is specifically configured to:

[0040] Obtaining front-side rated parameters, rear-side rated parameters and internal circuit characteristics of the bifacial photovoltaic module;

[0041] Calculating five front-side parameters of a bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the front-side rated parameters;

[0042] Calculating five parameters of the rear side of the bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the rear side rated parameters;

[0043] Calculating five parameters of the front side of the single bifacial photovoltaic cell under standard test conditions based on the five parameters of the front side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component;

[0044] The five parameters of the rear side of the single bifacial photovoltaic cell under standard test conditions are calculated based on the five parameters of the rear side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component.

[0045] In a possible implementation manner, the first determining module is specifically configured to:

[0046] Obtain the shadow area, shadow area radiation intensity, non-shadow area area and non-shadow area radiation intensity of a single bifacial photovoltaic cell in a shadow shielding scenario; determine the shadow area percentage based on the shadow area and the non-shadow area; determine the radiation shielding ratio based on the shadow area radiation intensity and the non-shadow area radiation intensity.

[0047] In a possible implementation, the second calculation module is specifically configured to:

[0048] According to the shadow area percentage and the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under standard test conditions are calculated respectively;

[0049] Calculate the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shielding scene according to the radiation shielding ratio and the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under the standard test conditions;

[0050] In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the front shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the front non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the front side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated;

[0051] In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the rear shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the rear side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated.

[0052] In a possible implementation manner, the second determining module is specifically configured to:

[0053] Using the target five parameters of the single bifacial photovoltaic cell in the shadow shading scene, an IV characteristic equation of the single bifacial photovoltaic cell in the shadow shading scene is calculated;

[0054] Based on the IV characteristic equation of the single bifacial photovoltaic cell, the IV characteristic equation of the bifacial photovoltaic cell string in the shadow shading scene is calculated;

[0055] Based on the IV characteristic equation of the bifacial photovoltaic cell string, the IV characteristic equation of the bifacial photovoltaic module in the shadow shading scene is calculated;

[0056] The output power of the bifacial photovoltaic module in a shadow-shading scenario is determined based on the IV characteristic equation of the bifacial photovoltaic module.

[0057] In a third aspect, the present application provides a device for evaluating the output power of a bifacial photovoltaic module in a shadow-blocking scenario, the device comprising: a processor, a memory, and a system bus;

[0058] The processor and the memory are connected via the system bus;

[0059] The memory is used to store one or more programs, and the one or more programs include instructions. When the instructions are executed by the processor, the processor executes the method for evaluating the output power of a bifacial photovoltaic module in a shadow shading scenario described in the first aspect above.

[0060] In a fourth aspect, the present application provides a computer-readable storage medium, which stores instructions. When the instructions are executed on a device, the device executes the method for evaluating the output power of a double-sided photovoltaic module in a shadow shading scenario described in the first aspect above.

[0061] It can be seen that this application has the following beneficial effects:

[0062] The embodiment of the present application provides an evaluation method for the output power of a bifacial photovoltaic module in a shadow-shading scenario, wherein the bifacial photovoltaic module is formed by connecting a plurality of single bifacial photovoltaic cells. The evaluation method includes: calculating five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, wherein the five parameters include photocurrent, dark saturation current of a diode, series resistance, parallel resistance, and diode thermal voltage. Determine the shadow area percentage and radiation shielding ratio of a single bifacial photovoltaic cell, wherein the shadow area percentage and radiation shielding ratio are used to characterize the shadow-shading condition of a single bifacial photovoltaic cell. According to the pre-constructed dual current source model of a bifacial photovoltaic cell in a shadow-shading scenario, the five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio, the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-shading scenario are calculated. According to the pre-constructed parallel equivalent circuit model of bifacial photovoltaic cells and the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-shading scenario, the target five parameters of a single bifacial photovoltaic cell in a shadow-shading scenario are calculated. Based on the five target parameters, the IV characteristic equations of a single bifacial photovoltaic cell, a bifacial photovoltaic cell string, and a bifacial photovoltaic module are calculated in turn to determine the output power of the bifacial photovoltaic module in a shadow-blocking scenario.

[0063] In this way, a dual current source model of bifacial photovoltaic cells in shadow-shading scenarios was constructed, and the five parameters of the front side of a single bifacial photovoltaic cell in shadow-shading scenarios and the five parameters of the rear side in shadow-shading scenarios were calculated respectively, which can take into account the electrical mismatch problem between the shadow area and the non-shadow area of ​​the cell; a parallel equivalent circuit model of bifacial photovoltaic cells considering the dynamic power generation characteristics of the front / rear side of bifacial photovoltaic cells was constructed to calculate the five parameters of the front and rear sides of a single bifacial photovoltaic cell as a whole. Combining the above two sub-models, a composite electrical model was established to calculate the target five parameters of a single bifacial photovoltaic cell in complex shadow-shading scenarios, and based on this, the IV characteristic equations of the cell, cell string and module were calculated in turn, so that the dynamic output power of the bifacial photovoltaic module in complex front and rear shadow-shading scenarios can be accurately evaluated.

[0064] The embodiment of the present application also provides a device corresponding to the above method, which has the same beneficial effects as the above method. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 A schematic diagram of a shadow shielding type provided in an embodiment of the present application;

[0066] Figure 2 A schematic diagram of an equivalent circuit of a photovoltaic module provided in an embodiment of the present application;

[0067] Figure 3 A schematic diagram of a flow chart of a method for evaluating the output power of a bifacial photovoltaic module in a shadow occlusion scenario provided in an embodiment of the present application;

[0068] Figure 4 A schematic diagram of the internal circuit of a double-sided photovoltaic module provided in an embodiment of the present application;

[0069] Figure 5 A schematic diagram of the distribution of shadow areas of a single bifacial photovoltaic cell in a shadow occlusion scenario provided in an embodiment of the present application;

[0070] Figure 6 A dual current source model diagram of a bifacial photovoltaic cell in a shadow occlusion scenario provided in an embodiment of the present application;

[0071] Figure 7 A parallel model diagram of a single bifacial photovoltaic cell with the front and rear sides connected in parallel provided in an embodiment of the present application;

[0072] Figure 8 A parallel equivalent circuit model diagram of bifacial photovoltaic cells provided in an embodiment of the present application;

[0073] Fig. 9 A composite electrical model diagram provided for an embodiment of the present application;

[0074] Fig.10A schematic diagram of a target five-parameter calculation process provided in an embodiment of the present application;

[0075] Fig.11 Another schematic flow chart of a method for evaluating the output power of a bifacial photovoltaic module in a shadow occlusion scenario provided in an embodiment of the present application;

[0076] Fig.12 A schematic diagram of the structure of a device for evaluating the output power of a bifacial photovoltaic module in a shadow-shading scenario provided in an embodiment of the present application;

[0077] Fig.13 A schematic diagram of the structure of a device for evaluating the output power of a bifacial photovoltaic module in a shadow occlusion scenario provided in an embodiment of the present application. DETAILED DESCRIPTION

[0078] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0079] In this application, relational terms such as first and second, etc. are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The terms "comprise", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of further restrictions, the elements defined by the statement "comprising a ..." do not exclude the presence of other identical elements in the process, method, article or equipment including the elements.

[0080] When calculating the power generation of bifacial photovoltaic modules, existing models usually use the bifacial coefficient measured under standard test conditions (STC). To calculate the equivalent radiation G of the bifacial photovoltaic module E . E As the actual radiation intensity G of the bifacial photovoltaic module pv , and substitute it into the equivalent circuit model to calculate the total output power of the bifacial PV module.

[0081] Among them, STC refers to the standard conditions for solar cell testing, that is, the solar radiation intensity is 1000W / m2 , battery temperature is 25℃, air quality AM1.5. The bifaciality factor refers to the minimum value of the ratio between the main electrical characteristics of the rear and front sides of a bifacial photovoltaic module. The bifaciality factor under standard test conditions is The calculation formula of equivalent radiation G is shown in formula (1). E The calculation formula of is shown in formula (2).

[0082]

[0083] Where: and They are the short-circuit current and maximum power of the front side of the bifacial PV module under STC conditions; and They are the short-circuit current and maximum power of the rear side of the bifacial photovoltaic module under STC conditions. F Represents the front radiation intensity; G R Indicates the rear side radiation intensity.

[0084] The equivalent circuit model is an electrical model that simulates the output power of photovoltaic modules. Its equivalent circuit diagram is as follows: Figure 2 The voltage-current relationship of a bifacial photovoltaic module can be found in formula (3).

[0085]

[0086] Where: I ph is the photocurrent of the bifacial photovoltaic module, I d is the current flowing through the diode, I p is the current flowing through the parallel resistor, I0 is the dark saturation current of the diode, R s is the series resistance of the bifacial photovoltaic module, R p is the parallel resistance of the bifacial photovoltaic module, V t is the diode thermal voltage.

[0087] I ph ,I0,R s , R p and V t are the five unknown parameters in formula (3). Substituting the parameters on the PV module nameplate into formula (3), we can solve the five parameters under STC conditions: I ph,stc 、V t,stc ,I 0,stc , R p,stc , R s,stc .

[0088] The magnitudes of the five unknown parameters are affected by the actual temperature T of the PV module. pv And the actual radiation intensity G on the component surface pvInfluence, formula (4) can transform the five parameters of the component under STC conditions into the five parameters under actual conditions:

[0089]

[0090] Where: G pv is the actual radiation intensity of the component; G stc is the radiation intensity under standard test conditions (1000W / m 2 );T pv is the actual temperature of the component; T stc is the component temperature under standard test conditions (273.15K); α is the short-circuit current temperature coefficient, q e is the electron charge (1.6×10 -19 C); E g is the energy band gap, K0 is the Boltzmann constant (1.38×10 -23 J / K).

[0091] After substituting the five parameters under actual working conditions into formula (3) to obtain the IV characteristic equation under actual working conditions, the output power of the bifacial photovoltaic module under actual working conditions can be calculated.

[0092] When the radiation conditions on the front / rear side of the bifacial PV module change or Figure 1 When the complex shadow is blocked, the power generation performance of the front / rear side will change. Simply using a constant bifacial coefficient to calculate the dynamic output power of the bifacial module will cause simulation errors. Figure 1 (b) When the shadow is blocked, the radiation of each area of ​​the same cell is usually averaged by area weight. This method ignores the electrical mismatch between the shadow area and the non-shadow area of ​​the cell, which will lead to simulation errors. In summary, it is difficult for existing methods to accurately simulate the output power of bifacial modules in complex front and rear shadow scenarios.

[0093] The embodiment of the present application provides a method and device for evaluating the output power of a bifacial photovoltaic module under a shadow shading scenario. The bifacial photovoltaic module is composed of multiple single bifacial photovoltaic cells connected. The evaluation method not only considers the dynamic electrical performance of the front / rear side of the bifacial photovoltaic module, but also effectively processes the power generation characteristics of the front / rear side of the module under complex shadow shading conditions.

[0094] The evaluation method includes: calculating five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, the five parameters including photocurrent, dark saturation current of the diode, series resistance, parallel resistance and diode thermal voltage. Determining the shadow area percentage and radiation shielding ratio of a single bifacial photovoltaic cell, the shadow area percentage and radiation shielding ratio are used to characterize the shadow shielding condition of the single bifacial photovoltaic cell. According to the pre-constructed dual current source model of bifacial photovoltaic cells in the shadow shielding scenario, the five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, the shadow area percentage and the radiation shielding ratio, the five parameters of the front / rear side of a single bifacial photovoltaic cell in the shadow shielding scenario are calculated. According to the pre-constructed parallel equivalent circuit model of bifacial photovoltaic cells and the five parameters of the front / rear side of a single bifacial photovoltaic cell in the shadow shielding scenario, the target five parameters of a single bifacial photovoltaic cell in the shadow shielding scenario are calculated. Based on the five target parameters, the IV characteristic equations of a single bifacial photovoltaic cell, a bifacial photovoltaic cell string, and a bifacial photovoltaic module are calculated in turn to determine the output power of the bifacial photovoltaic module in a shadow-blocking scenario.

[0095] A dual current source model of bifacial photovoltaic cells in shadow-shading scenarios was constructed to calculate the five parameters of the front side of a single bifacial photovoltaic cell in shadow-shading scenarios and the five parameters of the rear side in shadow-shading scenarios, respectively, which can take into account the electrical mismatch between the shadow area and the non-shadow area of ​​the cell; a parallel equivalent circuit model of bifacial photovoltaic cells considering the dynamic power generation characteristics of the front / rear side of bifacial photovoltaic cells was constructed to calculate the five parameters of the front and rear sides of a single bifacial photovoltaic cell as a whole. Combining the above two sub-models, a composite electrical model was established to calculate the target five parameters of a single bifacial photovoltaic cell in complex shadow-shading scenarios, based on which the IV characteristic equations of the cell, cell string and module were calculated in turn, so that the dynamic output power of the bifacial photovoltaic module in complex front and rear shadow-shading scenarios can be accurately evaluated.

[0096] To facilitate understanding of the technical solution provided in the embodiment of the present application, a method and device for evaluating the output power of a double-sided photovoltaic module in a shadow shading scenario provided in the embodiment of the present application are described below in conjunction with the accompanying drawings.

[0097] See also Figure 3 , Figure 3 A flow chart of a method for evaluating the output power of a bifacial photovoltaic module in a shadow-blocking scenario provided in an embodiment of the present application, the method specifically includes S301-305.

[0098] Bifacial photovoltaic modules are generally composed of several bifacial photovoltaic cell strings, each of which is composed of a single bifacial photovoltaic cell connected in series and a bypass diode. Figure 4 , Figure 4A schematic diagram of the internal circuit of a bifacial photovoltaic module provided in an embodiment of the present application, wherein n is the number of bifacial photovoltaic cell strings in the bifacial photovoltaic module, and m is the number of single bifacial photovoltaic cells protected by bypass diodes in the bifacial photovoltaic cell string.

[0099] The pre-built electrical sub-model 1 (double current source model of bifacial photovoltaic cells in shadow shading scenario) is used to calculate the five parameters of the front / rear side of each single bifacial photovoltaic cell in the shadow shading scenario. Please refer to the embodiment disclosed in the following step S303.

[0100] By using the pre-built electrical sub-model 2 (equivalent circuit model of bifacial photovoltaic cells in parallel), and considering the dynamic power generation characteristics of the front / rear side of a single bifacial photovoltaic cell, when the front / rear side radiation conditions change, the target five parameters of a single bifacial photovoltaic cell can still be accurately calculated. See the embodiment disclosed in step S304 below. The output power of the bifacial photovoltaic module is further determined based on the target five parameters.

[0101] It should be noted that the calculation of the five parameters in different scenarios is implemented in parallel. The calculation order of the five parameters shown in the embodiment of the present application is only an example and does not constitute a limitation thereto.

[0102] S301: Calculate five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions.

[0103] Calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, that is, calculate the five parameters of the front side of a single bifacial photovoltaic cell under standard test conditions and the five parameters of the rear side of a single bifacial photovoltaic cell under standard test conditions.

[0104] The nameplate of a bifacial photovoltaic module is generally engraved with the front side rated parameters and the rear side rated parameters, which are data under standard test conditions. Substitute the front side rated parameters and the rear side rated parameters into the preset IV characteristic equation shown in formula (3) to obtain the five parameters of the front side of the module and the five parameters of the rear side of the module under standard test conditions. Then, based on the internal circuit characteristics of the bifacial photovoltaic module, calculate the five parameters of the front side of a single bifacial photovoltaic cell under standard test conditions and the five parameters of the rear side under standard test conditions.

[0105] In a possible implementation, the calculation of five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions includes:

[0106] Obtain the front-side rated parameters, rear-side rated parameters and internal circuit characteristics of the bifacial photovoltaic module; calculate the five front-side parameters of the bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the front-side rated parameters; calculate the five rear-side parameters of the bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the rear-side rated parameters; calculate the five parameters of the front side of the single bifacial photovoltaic cell under standard test conditions based on the five front-side parameters of the module under standard test conditions and the internal circuit characteristics of the bifacial photovoltaic module; calculate the five parameters of the rear side of the single bifacial photovoltaic cell under standard test conditions based on the five rear-side parameters of the module under standard test conditions and the internal circuit characteristics of the bifacial photovoltaic module.

[0107] Depend on Figure 4 It can be seen that the bifacial photovoltaic module is composed of n×m bifacial photovoltaic cells connected in series, and the parameters of each bifacial photovoltaic cell can be determined by the following formula (5).

[0108]

[0109] In the formula, and They are five parameters of a single bifacial photovoltaic cell in a bifacial photovoltaic module under STC conditions, including photocurrent, dark saturation current of the diode, series resistance, parallel resistance and diode thermal voltage.

[0110] Substituting the front side rated parameters on the nameplate into the preset IV characteristic equation shown in formula (3), the five parameters of the front side of the bifacial PV module under STC conditions are obtained ( and ), which are the five parameters on the front side of the component.

[0111] Substituting the rear side rated parameters on the nameplate into the preset IV characteristic equation shown in formula (3), the five parameters of the rear side of the bifacial PV module under STC conditions are obtained ( and ), which are the five parameters of the back side of the component.

[0112] According to the internal circuit characteristics of the bifacial photovoltaic module, the five parameters of the front side of a single bifacial photovoltaic cell under STC conditions are calculated by the above formula (5): and ); and calculate the five parameters of the rear side of a single bifacial photovoltaic cell under STC conditions ( and ).

[0113] It should be noted that the specific steps provided in this application are only one possible implementation method, but are not limited to this implementation method and can be set according to user needs.

[0114] S302: Determine a shadow area percentage and a radiation shielding ratio of a single bifacial photovoltaic cell, wherein the shadow area percentage and the radiation shielding ratio are used to characterize a shadow shielding condition of the single bifacial photovoltaic cell.

[0115] In the shadow occlusion scenario, the shadow area distribution diagram of a single bifacial photovoltaic cell can be found in Figure 5 As shown, the figure shows the shading of a single surface on the front or rear side. A single bifacial photovoltaic cell with an area of ​​S includes a shadow area and a non-shadow area, wherein the shadow area is S1, the shadow area radiation intensity is G1, the non-shadow area is S2, and the non-shadow area radiation intensity is G2. The embodiment of the present application does not limit the specific implementation method of determining S, S1, S2, G1, and G2, and can be selected according to actual needs.

[0116] In one possible implementation, determining the shadow area percentage and radiation shielding ratio of a single bifacial photovoltaic cell includes: obtaining the shadow region area, shadow region radiation intensity, non-shadow region area, and non-shadow region radiation intensity of a single bifacial photovoltaic cell in a shadow shielding scenario; determining the shadow area percentage based on the shadow region area and the non-shadow region area; and determining the radiation shielding ratio based on the shadow region radiation intensity and the non-shadow region radiation intensity.

[0117] Because both the front and back sides of a single bifacial photovoltaic cell may be blocked, the embodiments of the present application may calculate the shadow area percentage and radiation blocking ratio of the front side and the shadow area percentage and radiation blocking ratio of the back side respectively during execution.

[0118] The percentage of shaded area (POSA) is sa (sa>0.01) and is calculated by formula (6). The shading ratio (SR) is sr (sr>0.01) and is calculated by formula (7).

[0119]

[0120] The two indicators POSA and SR can reflect the local shadowing condition of a single bifacial photovoltaic cell.

[0121] S303: Calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-blocking scenario based on a pre-constructed dual current source model of the bifacial photovoltaic cell in a shadow-blocking scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio.

[0122] Through the pre-constructed dual current source model of bifacial photovoltaic cells in shadow shading scenarios, the mathematical relationship between the five parameters of the front / rear side of a single bifacial photovoltaic cell in shadow shading scenarios and POSA and SR can be obtained.

[0123] Among them, the dual current source model of the bifacial photovoltaic cell in the shadow shading scenario can be used to calculate the five parameters of any side of a single bifacial photovoltaic cell in the partial shadow shading scenario.

[0124] In a possible implementation, the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-blocking scenario are calculated based on a pre-constructed dual current source model of the bifacial photovoltaic cell in a shadow-blocking scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio, including:

[0125] According to the shadow area percentage and the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under standard test conditions are calculated respectively;

[0126] Calculate the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shielding scene according to the radiation shielding ratio and the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under the standard test conditions;

[0127] In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the front shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the front non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the front side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated;

[0128] In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the rear shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the rear side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated.

[0129] According to the shadow area percentage POSA, the five parameters of the front shadow area of ​​a single bifacial photovoltaic cell under STC conditions are calculated ( and ) and the five parameters of the front non-shadow area under STC conditions ( and ); Similarly, the five parameters of the rear shadow area of ​​a single bifacial photovoltaic cell under STC conditions are calculated based on the shadow area percentage POSA ( and ) and the five parameters of the rear non-shadow area under STC conditions ( and ).

[0130] According to the radiation shielding ratio SR, the five parameters of the shadow area on the front side of a single bifacial photovoltaic cell under actual radiation conditions are calculated ( and ) and the five parameters of the front non-shadow area under actual radiation conditions ( and ); Similarly, the five parameters of the shadow area behind a single bifacial photovoltaic cell under actual radiation conditions are calculated based on the radiation shielding ratio SR ( and ) and the five parameters of the rear non-shadow area under actual radiation conditions ( and ).

[0131] In the embodiment of the present application, the actual radiation condition is a shadow occlusion scene in actual application, and the following is expressed in terms of a shadow occlusion scene.

[0132] After obtaining the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​a single bifacial photovoltaic cell in the aforementioned shadow shading scene, the five parameters of the front side of a single bifacial photovoltaic cell in the shadow shading scene are calculated according to the dual current source model of the bifacial photovoltaic cell in the shadow shading scene ( and ) and the five parameters of the rear side of a single bifacial photovoltaic cell in a shadow occlusion scenario ( and ).

[0133] The following describes the modeling and calculation process of calculating the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow occlusion scenario according to an embodiment of the present application.

[0134] In the embodiment of the present application, since the photocurrent on any one side of the two sides of a single bifacial photovoltaic cell is equal to the sum of the photocurrent in the shadow area and the photocurrent in the non-shadow area, it can be assumed that the shadow area and the non-shadow area of ​​the single bifacial photovoltaic cell are connected in parallel, and the dual current source model diagram of any one side of the two sides of the single bifacial photovoltaic cell in the shadow shading scene is as follows: Figure 6 shown.

[0135] Figure 6 middle is the photocurrent in the shaded area, is the photocurrent in the non-shaded area, is the series resistance in the shaded area, is the series resistance of the non-shaded area, is the parallel resistance in the shaded area, is the parallel resistance of the non-shaded area, is the current flowing through the diode in the parallel circuit, through the dark saturation current and thermal voltage calculate.

[0136] In a specific embodiment, the photocurrent of the front side of a single bifacial photovoltaic cell under a shadow shading scenario is And the photocurrent of the rear side in the shadow occlusion scene Provide explanation.

[0137] Since the photocurrent is proportional to the cell area, the photocurrent of the front or back side of a single bifacial photovoltaic cell under standard test conditions can be calculated based on the shadow area percentage POSA. and It can be calculated according to POSA, the calculation formula is:

[0138]

[0139] The above formula (8) is used to calculate the photocurrent of the shadow area and non-shadow area on either side of a single bifacial photovoltaic cell under STC conditions. Refer to formula (8) to calculate the photocurrent of the shadow area and non-shadow area on the front side of a single bifacial photovoltaic cell under standard test conditions. Similarly, refer to the above formula (8) to calculate the photocurrent of the shadow area and non-shadow area on the rear side of a single bifacial photovoltaic cell under standard test conditions:

[0140] Since the photocurrent is proportional to the radiation intensity, the photocurrent of the shadow area / non-shadow area in the shadow shading scene can be calculated based on the radiation shielding ratio SR and the photocurrent of the shadow area / non-shadow area under standard test conditions. and It can be calculated according to SR, the calculation formula is:

[0141]

[0142] The above formula (9) is used to calculate the photocurrent of the shadow area and non-shadow area on either side of a single bifacial photovoltaic cell in a shadow-shaded scene. Referring to the above formula (9), the photocurrent of the shadow area and non-shadow area on the front side of a single bifacial photovoltaic cell in a shadow-shaded scene is calculated respectively. Similarly, refer to the above formula (9) to calculate the photocurrent of the shadow area and non-shadow area on the rear side of a single bifacial photovoltaic cell in the shadow occlusion scenario:

[0143] Photocurrent of a single bifacial photovoltaic cell under shadow occlusion Size:

[0144]

[0145] The above formula (10) is used to calculate the photocurrent of any side of a single bifacial photovoltaic cell in a shadow-shaded scene. Referring to the above formula (10), the photocurrent of the front side of a single bifacial photovoltaic cell in a shadow-shaded scene is calculated as And the photocurrent of the rear side in the shadow occlusion scene

[0146] In a specific embodiment, the series resistance of the front side of a single bifacial photovoltaic cell in a shadow-shading scenario is Series resistance of the rear side in shadow occlusion scenario Parallel resistor on the front side in shadow occlusion scenario And the parallel resistance of the rear side in the shadow occlusion scene Provide explanation.

[0147] Since the resistance of a material is inversely proportional to its cross-sectional area, the series resistance of different cell regions and parallel resistor It can be calculated according to POSA, the calculation formula is:

[0148]

[0149] The above formula (11) is used to calculate the series resistance of the shadow area and non-shadow area on either side of a single bifacial photovoltaic cell under STC conditions. Referring to the above formula (11), the series resistance of the shadow area and non-shadow area on the front side of a single bifacial photovoltaic cell under standard test conditions is calculated respectively. Similarly, refer to the above formula (11) to calculate the series resistance of the shadow area and non-shadow area on the rear side of a single bifacial photovoltaic cell under standard test conditions:

[0150] The above formula (12) is used to calculate the parallel resistance of the shadow area and non-shadow area on either side of a single bifacial photovoltaic cell under STC conditions. Refer to the above formula (12) to calculate the parallel resistance of the shadow area and non-shadow area on the front side of a single bifacial photovoltaic cell under standard test conditions. Similarly, refer to the above formula (12) to calculate the parallel resistance of the shadow area and non-shadow area on the rear side of a single bifacial photovoltaic cell under standard test conditions:

[0151] According to SR, the series resistance of different battery areas in the shadow occlusion scenario can be calculated by formulas (13)-(14): and parallel resistor

[0152]

[0153] The above formula (13) is used to calculate the series resistance of the shadow area and non-shadow area on either side of a single bifacial photovoltaic cell in a shadow occlusion scenario. Referring to the above formula (13), the series resistance of the shadow area and non-shadow area on the front side of a single bifacial photovoltaic cell in a shadow occlusion scenario is calculated respectively. Similarly, refer to the above formula (13) to calculate the series resistance of the shadow area and non-shadow area on the rear side of a single bifacial photovoltaic cell in the shadow occlusion scenario:

[0154] The above formula (14) is used to calculate the parallel resistance of the shadow area and non-shadow area on either side of a single bifacial photovoltaic cell in a shadow occlusion scenario. Referring to the above formula (14), the parallel resistance of the shadow area and non-shadow area on the front side of a single bifacial photovoltaic cell in a shadow occlusion scenario is calculated respectively. Similarly, refer to the above formula (14) to calculate the parallel resistance of the shadow area and non-shadow area on the rear side of a single bifacial photovoltaic cell in the shadow occlusion scenario:

[0155] Based on the dual current source model under the shadow shading scenario of the bifacial cell, the series resistance of a single bifacial photovoltaic cell under the shadow shading scenario and parallel resistor It can be calculated by formula (15)-(16):

[0156]

[0157]

[0158] The above formula (15) is used to calculate the series resistance of any side of a single bifacial photovoltaic cell in a shadow-shaded scenario. Referring to the above formula (15), the series resistance of the front side of a single bifacial photovoltaic cell in a shadow-shaded scenario is calculated as and the series resistance of the rear side in the shadow occlusion scenario

[0159] The above formula (16) is used to calculate the parallel resistance of any side of a single bifacial photovoltaic cell in a shadow-shaded scene. Referring to the above formula (16), the parallel resistance of the front side of a single bifacial photovoltaic cell in a shadow-shaded scene is calculated as And the parallel resistance of the rear side in the shadow occlusion scene

[0160] In a specific embodiment, the thermal voltage of a single bifacial photovoltaic cell under a shadow shading scenario is and dark saturation current Provide explanation.

[0161] Since the thermal voltage and dark saturation current are not affected by the radiation intensity but only by the temperature, the thermal voltage under the shadow of the cell is and dark saturation current Keeping in line with the uniform distribution of solar cell radiation, its size is calculated as formula (17)-(18):

[0162]

[0163] The above formula (17) is used to calculate the thermal voltage of any side of a single bifacial photovoltaic cell in a shadow-shaded scenario. Referring to the above formula (17), the voltage of the front side of a single bifacial photovoltaic cell in a shadow-shaded scenario is obtained: And the voltage of the back side in the shadow occlusion scene

[0164] The above formula (18) is used to calculate the dark saturation current of any side of a single bifacial photovoltaic cell in a shadow-shaded scene. Referring to the above formula (18), the dark saturation current of the front side of a single bifacial photovoltaic cell in a shadow-shaded scene is obtained: And the voltage of the back side in the shadow occlusion scene

[0165] Through the above steps, the five parameters of the front side of a single bifacial photovoltaic cell in the shadow occlusion scene can be calculated respectively ( and ) and the five parameters of the back side in the shadow occlusion scene ( and ).

[0166] S304: Calculate the target five parameters of the single bifacial photovoltaic cell in the shadow-shading scenario according to the pre-constructed bifacial photovoltaic cell parallel equivalent circuit model and the five parameters of the front / rear side of the single bifacial photovoltaic cell in the shadow-shading scenario.

[0167] Both the front and back sides of a single bifacial photovoltaic cell may have Figure 5 In the pre-built bifacial photovoltaic cell parallel equivalent circuit model, the target five parameters of a single bifacial photovoltaic cell in the shadow shading scenario are calculated based on the five parameters of the front side in the shadow shading scenario and the five parameters of the rear side in the shadow shading scenario.

[0168] The total photocurrent of a single bifacial photovoltaic cell is equal to the sum of the photocurrent on the front side and the photocurrent on the back side. The open circuit voltage on the front side is approximately equal to the open circuit voltage on the back side. Therefore, it can be assumed that the front and back sides of a single bifacial photovoltaic cell are connected in parallel. The parallel model can be found in Figure 7 The left dashed box represents the front side of a single bifacial photovoltaic cell, and the right dashed box represents the back side of a single bifacial photovoltaic cell. The series resistance of the front and back sides Located on the main line of the parallel circuit.

[0169] Will Figure 7 Combining the front and rear circuits in the parallel model shown, we get Figure 8 The parallel equivalent circuit model shown is the parallel equivalent circuit model of bifacial photovoltaic cells. The parallel equivalent circuit model of bifacial photovoltaic cells is used to calculate the target five parameters of a single bifacial photovoltaic cell in a shadow occlusion scenario. Among them, the first dotted box from left to right represents the combined target photocurrent The second dotted box represents the combined target parallel resistor The third dashed box represents the combined target series resistance

[0170] By using formulas (19)-(21) we can calculate and

[0171]

[0172] Since the thermal voltage and dark saturation current are only affected by temperature, and the temperature of the front and back sides of the bifacial photovoltaic module is the same, the combined target dark saturation current is and target thermal voltage Approximately equal to the value on the front side of the component:

[0173]

[0174] According to the parallel circuit characteristics between the shadow area and the non-shadow area, the target five parameters of a single bifacial photovoltaic cell in the shadow occlusion scene can be calculated by the above formulas (19)-(23): and ).

[0175] The above respectively describes the realization of electrical sub-model 1 (dual current source model of bifacial photovoltaic cells in shadow occlusion scenario) and electrical sub-model 2 (equivalent circuit model of bifacial photovoltaic cells in parallel). On this basis, the following is established: Fig. 9 The composite electrical model shown in Figure 1 can accurately evaluate the dynamic output power of bifacial photovoltaic cells in complex shadow shading scenarios, that is, the model not only takes into account the bifacial power generation characteristics of bifacial photovoltaic modules, but also effectively handles the power generation characteristics of the front / rear sides of bifacial photovoltaic modules in complex shadow shading scenarios at the same time.

[0176] See also Fig.10 , Fig.10 A schematic diagram of a target five-parameter calculation process provided in an embodiment of the present application.

[0177] The electrical sub-model 1 can be used to calculate the photocurrent in the shadowed and non-shadowed areas on the front side of a single bifacial photovoltaic cell. Parallel resistance and series resistance And further calculate the five parameters of the front side of a single bifacial photovoltaic cell in the shadow occlusion scene ( and ). Similarly, the five parameters of the rear side of a single bifacial photovoltaic cell in the shadow occlusion scenario are calculated by the electrical sub-model 1 ( and ).

[0178] Based on the five parameters of the front side of a single bifacial photovoltaic cell in a shadow-shaded scenario and the five parameters of the back side in a shadow-shaded scenario, the overall five parameters of the front and back sides of a single bifacial photovoltaic cell in a shadow-shaded scenario can be calculated through the electrical sub-model 2 ( and ), namely the target five parameters.

[0179] S305: Based on the target five parameters of the single bifacial photovoltaic cell in the shadow-blocking scenario, IV characteristic equations of the single bifacial photovoltaic cell, the bifacial photovoltaic cell string and the bifacial photovoltaic module are calculated in sequence to determine the output power of the bifacial photovoltaic module in the shadow-blocking scenario.

[0180] In order to calculate the total output power of each single bifacial photovoltaic cell in the entire bifacial photovoltaic module under different front / rear shadow shading scenarios, based on the five parameters of a single bifacial photovoltaic cell in the front / rear shadow shading scenario, the IV characteristic equation of the single bifacial photovoltaic cell, the IV characteristic equation of the bifacial photovoltaic cell string and the IV characteristic equation of the bifacial photovoltaic module are calculated in turn.

[0181] In one possible implementation, based on the target five parameters of the single bifacial photovoltaic cell in the shadow-shading scenario, the IV characteristic equations of the single bifacial photovoltaic cell, the bifacial photovoltaic cell string and the bifacial photovoltaic module are calculated in sequence to determine the output power of the bifacial photovoltaic module in the shadow-shading scenario, including: using the target five parameters of the single bifacial photovoltaic cell in the shadow-shading scenario to calculate the IV characteristic equation of the single bifacial photovoltaic cell in the shadow-shading scenario; based on the IV characteristic equation of the single bifacial photovoltaic cell, calculate the IV characteristic equation of the bifacial photovoltaic cell string in the shadow-shading scenario; based on the IV characteristic equation of the bifacial photovoltaic cell string, calculate the IV characteristic equation of the bifacial photovoltaic module in the shadow-shading scenario; based on the IV characteristic equation of the bifacial photovoltaic cell string, calculate the IV characteristic equation of the bifacial photovoltaic module in the shadow-shading scenario; determine the output power of the bifacial photovoltaic module in the shadow-shading scenario based on the IV characteristic equation of the bifacial photovoltaic module.

[0182] In a specific embodiment, the process of determining the IV characteristic equation of a single bifacial photovoltaic cell is described below.

[0183] According to the output current I of the bifacial photovoltaic module and the photocurrent of a single bifacial photovoltaic cell To determine whether the solar cell can output power normally, the photovoltaic solar cell can be divided into two working states and the IV characteristic equation of each solar cell can be calculated.

[0184] When the output current I of the bifacial photovoltaic module is less than the photocurrent of a single bifacial photovoltaic cell When the output current I of the bifacial photovoltaic module is greater than or equal to the photocurrent of a single bifacial photovoltaic cell, the single bifacial photovoltaic cell in the bifacial photovoltaic cell string can output power normally; when the output current I of the bifacial photovoltaic module is greater than or equal to the photocurrent of a single bifacial photovoltaic cell When the photovoltaic cell is reverse biased and consumes power, it causes a negative terminal voltage on the photovoltaic cell. Therefore, the IV characteristic equation of a single bifacial photovoltaic cell is:

[0185]

[0186] Wherein, q represents the qth single bifacial photovoltaic cell in the bifacial photovoltaic cell string, LambertW is the Lambert W function,

[0187] In a specific embodiment, the process of determining the IV characteristic equation of a bifacial photovoltaic cell string and the IV characteristic equation of a bifacial photovoltaic module is described below.

[0188] Keep the current the same, add the voltage of each single bifacial photovoltaic cell in the bifacial photovoltaic cell string, determine whether the bypass diode of the bifacial photovoltaic cell string is turned on, and then calculate the IV characteristic equation of the bifacial photovoltaic cell string. str is negative and reaches the conduction voltage of the bypass diode -V bd When the bypass diode of the bifacial photovoltaic cell string is turned on, the terminal voltage of the bifacial photovoltaic cell string will remain at -V bd Therefore, the IV characteristic equation of the bifacial photovoltaic cell string is:

[0189]

[0190] Since the bifacial photovoltaic cell strings are connected in series to keep the current the same, the voltage of each bifacial photovoltaic cell string can be Add together to calculate the total component voltage V pv :

[0191]

[0192] The power of the bifacial photovoltaic module can be determined according to the IV characteristic equation of the output current and output voltage of the bifacial photovoltaic module.

[0193] See also Fig.11 , Fig.11 Another flow chart of a method for evaluating the output power of a bifacial photovoltaic module in a shadow-shading scenario provided in an embodiment of the present application. The five parameters of the front / rear side of the bifacial photovoltaic module under STC conditions are calculated using the front / rear side rated parameters and the IV characteristic equation of the bifacial photovoltaic module, and the five parameters of the front / rear side of a single bifacial photovoltaic cell under STC conditions are calculated based on the internal circuit characteristics of the photovoltaic module. The five parameters of the shadow area and non-shadow area of ​​the front / rear side of a single bifacial photovoltaic cell under STC conditions are calculated using POSA, and the five parameters of the shadow area and non-shadow area of ​​the front / rear side of a single bifacial photovoltaic cell under shadow-shading scenarios are calculated based on SA. A dual current source model of a bifacial photovoltaic cell in a shadow-shading scenario is constructed to calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-shading scenario.

[0194] A parallel equivalent circuit model of bifacial photovoltaic cells is constructed. The model characterizes the dynamic power generation performance of the front / rear side of the cell through the five parameters of the front and rear sides of the bifacial photovoltaic cells respectively. According to the parallel circuit characteristics between the front and rear sides of a single bifacial photovoltaic cell, the target five parameters of the single bifacial photovoltaic cell in the shadow shading scenario are calculated, and based on this, the IV characteristic equations of the single bifacial photovoltaic cell, battery string and module are calculated in turn, finally achieving accurate evaluation of the output power of bifacial photovoltaic modules in complex shadow shading scenarios.

[0195] based on Fig.11 From the specific steps, it can be seen that the dual current source model (electrical sub-model 1) of the bifacial photovoltaic cell in the shadow-shading scene proposed in the embodiment of the present application can take into account the electrical mismatch between the shadow area and the non-shadow area of ​​a single bifacial photovoltaic cell, thereby improving the accuracy of the component power simulation results in the battery shadow-shading scene; in response to the simulation error problem caused by simulating the dynamic output power of the bifacial photovoltaic module using a constant bifacial coefficient, the embodiment of the present application proposes a bifacial photovoltaic cell parallel equivalent circuit model (electrical sub-model 2), which can characterize its dynamic electrical performance through the five parameters of the front / rear side of the battery, and calculate the five parameters of the whole of a single bifacial photovoltaic cell according to the parallel circuit characteristics between the front / rear side of the battery, and further accurately calculate the output power of the bifacial photovoltaic module, thereby improving the accuracy of the simulation. The composite electrical model proposed on the basis of the above two electrical sub-models calculates the target five parameters of a single bifacial photovoltaic cell in a complex shadow-shading scene, and based on this, calculates the IV characteristic equations of the battery, battery string and module in turn, which can accurately evaluate the dynamic output power of the bifacial photovoltaic module in the complex front and rear side shadow-shading scene. The composite electrical model not only improves the accuracy when simulating the output power of bifacial photovoltaic modules, but also adapts to complex local shadowing scenarios on the front and back sides, and has a wider range of application scenarios.

[0196] The above embodiment of the present application provides a method for evaluating the output power of a bifacial photovoltaic module in a shadow-shading scenario based on the above. Next, an evaluation device for the output power of a bifacial photovoltaic module in a shadow-shading scenario provided in the embodiment of the present application is described, which is used to perform the above Figure 3 Next, the function of the device for evaluating the output power of a bifacial photovoltaic module in a shadow-shading scene is described. The schematic diagram of the structure of the device for evaluating the output power of a bifacial photovoltaic module in a shadow-shading scene is shown in FIG. Fig.12 As shown, it includes a first calculation module 1201, a first determination module 1202, a second calculation module 1203, a third calculation module 1204 and a second determination module 1205.

[0197] The bifacial photovoltaic module is formed by connecting a plurality of single bifacial photovoltaic cells, wherein:

[0198] The first calculation module 1201 is used to calculate five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, wherein the five parameters include photocurrent, dark saturation current of the diode, series resistance, parallel resistance and diode thermal voltage;

[0199] A first determination module 1202 is used to determine a shadow area percentage and a radiation shielding ratio of a single bifacial photovoltaic cell, wherein the shadow area percentage and the radiation shielding ratio are used to characterize the shadow shielding condition of the single bifacial photovoltaic cell;

[0200] The second calculation module 1203 is used to calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-shading scenario according to the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow-shading scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio;

[0201] The third calculation module 1204 is used to calculate the target five parameters of a single bifacial photovoltaic cell in a shadow-shading scenario according to the pre-constructed bifacial photovoltaic cell parallel equivalent circuit model and the five parameters of the front / rear side of the single bifacial photovoltaic cell in the shadow-shading scenario;

[0202] The second determination module 1205 is used to calculate the IV characteristic equations of the single bifacial photovoltaic cell, the bifacial photovoltaic cell string and the bifacial photovoltaic module in sequence based on the target five parameters of the single bifacial photovoltaic cell in the shadow shading scenario, and determine the output power of the bifacial photovoltaic module in the shadow shading scenario.

[0203] In a possible implementation, the first calculation module 1201 is specifically configured to:

[0204] Obtaining front-side rated parameters, rear-side rated parameters and internal circuit characteristics of the bifacial photovoltaic module;

[0205] Calculating five front-side parameters of a bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the front-side rated parameters;

[0206] Calculating five parameters of the rear side of the bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the rear side rated parameters;

[0207] Calculating five parameters of the front side of the single bifacial photovoltaic cell under standard test conditions based on the five parameters of the front side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component;

[0208] The five parameters of the rear side of the single bifacial photovoltaic cell under standard test conditions are calculated based on the five parameters of the rear side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component.

[0209] In a possible implementation, the first determining module 1202 is specifically configured to:

[0210] Obtain the shadow area, shadow area radiation intensity, non-shadow area area and non-shadow area radiation intensity of a single bifacial photovoltaic cell in a shadow shielding scenario; determine the shadow area percentage based on the shadow area and the non-shadow area; determine the radiation shielding ratio based on the shadow area radiation intensity and the non-shadow area radiation intensity.

[0211] In a possible implementation, the second calculation module 1203 is specifically configured to:

[0212] According to the shadow area percentage and the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under standard test conditions are calculated respectively;

[0213] Calculate the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shielding scene according to the radiation shielding ratio and the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under the standard test conditions;

[0214] In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the front shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the front non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the front side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated;

[0215] In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the rear shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the rear side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated.

[0216] In a possible implementation, the second determining module 1205 is specifically configured to:

[0217] Using the target five parameters of the single bifacial photovoltaic cell in the shadow shading scene, an IV characteristic equation of the single bifacial photovoltaic cell in the shadow shading scene is calculated;

[0218] Based on the IV characteristic equation of the single bifacial photovoltaic cell, the IV characteristic equation of the bifacial photovoltaic cell string in the shadow shading scene is calculated;

[0219] Based on the IV characteristic equation of the bifacial photovoltaic cell string, the IV characteristic equation of the bifacial photovoltaic module in the shadow shading scene is calculated;

[0220] The output power of the bifacial photovoltaic module in a shadow-shading scenario is determined based on the IV characteristic equation of the bifacial photovoltaic module.

[0221] The embodiment of the present application provides an evaluation device for the output power of a bifacial photovoltaic module in a shadow-blocking scenario, comprising a first calculation module, a first determination module, a second calculation module, a third calculation module and a second determination module. The bifacial photovoltaic module is formed by connecting a plurality of single bifacial photovoltaic cells. The first calculation module is used to calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions. The first determination module is used to determine the shadow area percentage and the radiation shielding ratio of a single bifacial photovoltaic cell, and the shadow area percentage and the radiation shielding ratio are used to characterize the shadow shielding condition of the single bifacial photovoltaic cell. The second calculation module is used to calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-blocking scenario according to a pre-constructed dual current source model of a bifacial photovoltaic cell in a shadow-blocking scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio. The third calculation module is used to calculate the target five parameters of a single bifacial photovoltaic cell in a shadow-shading scene according to the pre-constructed parallel equivalent circuit model of bifacial photovoltaic cells and the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-shading scene. The second determination module is used to sequentially calculate the IV characteristic equations of a single bifacial photovoltaic cell, a bifacial photovoltaic cell string and a bifacial photovoltaic module based on the target five parameters of the single bifacial photovoltaic cell in a shadow-shading scene, and determine the output power of the bifacial photovoltaic module in a shadow-shading scene.

[0222] In this way, a dual current source for bifacial photovoltaic cells in shadow-shading scenarios is constructed, and the five parameters of the front side of a single bifacial photovoltaic cell in shadow-shading scenarios and the five parameters of the rear side in shadow-shading scenarios are calculated respectively, which can take into account the electrical mismatch problem between the shadow area and the non-shadow area of ​​the cell; a parallel equivalent circuit model of bifacial photovoltaic cells considering the dynamic power generation characteristics of the front / rear side of bifacial photovoltaic cells is constructed to calculate the five parameters of the front and rear sides of a single bifacial photovoltaic cell as a whole. Combining the above two sub-models, a composite electrical model is established to calculate the target five parameters of bifacial photovoltaic cells in complex shadow-shading scenarios, and based on this, the IV characteristic equations of cells, cell strings and modules are calculated in turn, so that the dynamic output power of bifacial photovoltaic modules in complex front and rear shadow-shading scenarios can be accurately evaluated.

[0223] Based on the method for evaluating the output power of a bifacial photovoltaic module in a shadow-shading scenario provided by the above method embodiment, the present application embodiment provides an evaluation device for the output power of a bifacial photovoltaic module in a shadow-shading scenario, see Fig.13 , the device includes: a processor, a memory, and a system bus;

[0224] The processor and the memory are connected via the system bus;

[0225] The memory is used to store one or more programs, and the one or more programs include instructions. When the instructions are executed by the processor, the processor executes the method for evaluating the output power of a bifacial photovoltaic component in a shadow shading scenario described in any of the above embodiments.

[0226] Based on the method for evaluating the output power of a bifacial photovoltaic module in a shadow-blocking scenario provided in the above-mentioned method embodiment, an embodiment of the present application provides a computer-readable storage medium, which stores instructions. When the instructions are executed on a device, the device executes the method for evaluating the output power of a bifacial photovoltaic module in a shadow-blocking scenario described in any of the above-mentioned embodiments.

[0227] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device or device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device and device embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0228] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0229] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for evaluating the output power of a bifacial photovoltaic module in a shadow-blocking scenario, characterized in that: The bifacial photovoltaic assembly is formed by connecting a plurality of single bifacial photovoltaic cells, and the evaluation method comprises: Calculate five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, the five parameters including photocurrent, dark saturation current of the diode, series resistance, parallel resistance and diode thermal voltage; Determine the shadow area percentage and radiation shielding ratio of a single bifacial photovoltaic cell, wherein the shadow area percentage and the radiation shielding ratio are used to characterize the shadow shielding condition of the single bifacial photovoltaic cell; Calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-shading scenario according to a pre-constructed dual current source model of the bifacial photovoltaic cell in a shadow-shading scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio; Calculate the target five parameters of a single bifacial photovoltaic cell in a shadow-shading scenario according to the pre-constructed bifacial photovoltaic cell parallel equivalent circuit model and the five parameters of the front / rear side of the single bifacial photovoltaic cell in a shadow-shading scenario; Based on the target five parameters of the single bifacial photovoltaic cell in the shadow-blocking scenario, the IV characteristic equations of the single bifacial photovoltaic cell, the bifacial photovoltaic cell string and the bifacial photovoltaic module are calculated in turn to determine the output power of the bifacial photovoltaic module in the shadow-blocking scenario.

2. The evaluation method according to claim 1, characterized in that: The calculation of the five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions includes: Obtaining front-side rated parameters, rear-side rated parameters and internal circuit characteristics of the bifacial photovoltaic module; Calculating five front-side parameters of a bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the front-side rated parameters; Calculating five parameters of the rear side of the bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the rear side rated parameters; Calculating five parameters of the front side of the single bifacial photovoltaic cell under standard test conditions based on the five parameters of the front side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component; The five parameters of the rear side of the single bifacial photovoltaic cell under standard test conditions are calculated based on the five parameters of the rear side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component.

3. The evaluation method according to claim 1, characterized in that: Determining the shadow area percentage and radiation shielding ratio of a single bifacial photovoltaic cell includes: Obtain the shadow area, radiation intensity of the shadow area, non-shadow area, and radiation intensity of the non-shadow area of ​​a single bifacial photovoltaic cell in a shadow-blocking scenario; Determining the shadow area percentage based on the shadow area and the non-shadow area; The radiation shielding ratio is determined based on the shadow area radiation intensity and the non-shadow area radiation intensity.

4. The evaluation method according to claim 3, characterized in that: The method calculates the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-blocking scenario according to the pre-constructed dual current source model of the bifacial photovoltaic cell in a shadow-blocking scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio, including: According to the shadow area percentage and the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under standard test conditions are calculated respectively; According to the radiation shielding ratio, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under the standard test conditions, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shielding scene are calculated; In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the front shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the front non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the front side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated; In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the rear shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the rear side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated.

5. The evaluation method according to claim 1, characterized in that: The method of calculating the IV characteristic equations of the single bifacial photovoltaic cell, the bifacial photovoltaic cell string and the bifacial photovoltaic module in sequence based on the target five parameters of the single bifacial photovoltaic cell in the shadow shading scene, and determining the output power of the bifacial photovoltaic module in the shadow shading scene, includes: Using the target five parameters of the single bifacial photovoltaic cell in the shadow shading scene, an IV characteristic equation of the single bifacial photovoltaic cell in the shadow shading scene is calculated; Based on the IV characteristic equation of the single bifacial photovoltaic cell, the IV characteristic equation of the bifacial photovoltaic cell string in the shadow shading scene is calculated; Based on the IV characteristic equation of the bifacial photovoltaic cell string, the IV characteristic equation of the bifacial photovoltaic module in the shadow shading scene is calculated; The output power of the bifacial photovoltaic module in a shadow-shading scenario is determined based on the IV characteristic equation of the bifacial photovoltaic module.

6. A device for evaluating the output power of a bifacial photovoltaic module in a shadow-blocking scene, characterized in that: The bifacial photovoltaic assembly is formed by connecting a plurality of single bifacial photovoltaic cells, and the evaluation device comprises: A first calculation module is used to calculate five parameters of the front / rear side of a single bifacial photovoltaic cell under standard test conditions, wherein the five parameters include photocurrent, dark saturation current of the diode, series resistance, parallel resistance and diode thermal voltage; A first determination module is used to determine the shadow area percentage and radiation shielding ratio of a single bifacial photovoltaic cell, wherein the shadow area percentage and the radiation shielding ratio are used to characterize the shadow shielding condition of the single bifacial photovoltaic cell; The second calculation module is used to calculate the five parameters of the front / rear side of a single bifacial photovoltaic cell in a shadow-blocking scenario according to a pre-constructed dual current source model of the bifacial photovoltaic cell in a shadow-blocking scenario, the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the shadow area percentage, and the radiation shielding ratio; A third calculation module is used to calculate the target five parameters of a single bifacial photovoltaic cell in a shadow-shading scenario according to a pre-constructed bifacial photovoltaic cell parallel equivalent circuit model and the five parameters of the front / rear side of the single bifacial photovoltaic cell in the shadow-shading scenario; The second determination module is used to calculate the IV characteristic equations of the single bifacial photovoltaic cell, the bifacial photovoltaic cell string and the bifacial photovoltaic module in sequence based on the target five parameters of the single bifacial photovoltaic cell in the shadow shading scenario, and determine the output power of the bifacial photovoltaic module in the shadow shading scenario.

7. The evaluation device according to claim 6, characterized in that The first calculation module is specifically used for: Obtaining front-side rated parameters, rear-side rated parameters and internal circuit characteristics of the bifacial photovoltaic module; Calculating five front-side parameters of a bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the front-side rated parameters; Calculating five parameters of the rear side of the bifacial photovoltaic module under standard test conditions using a preset IV characteristic equation and the rear side rated parameters; Calculating five parameters of the front side of the single bifacial photovoltaic cell under standard test conditions based on the five parameters of the front side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component; The five parameters of the rear side of the single bifacial photovoltaic cell under standard test conditions are calculated based on the five parameters of the rear side of the component under the standard test conditions and the internal circuit characteristics of the bifacial photovoltaic component.

8. The evaluation device according to claim 6, characterized in that The first determining module is specifically configured to: Obtain the shadow area, radiation intensity of the shadow area, non-shadow area, and radiation intensity of the non-shadow area of ​​a single bifacial photovoltaic cell in a shadow-blocking scenario; Determining the shadow area percentage based on the shadow area and the non-shadow area; The radiation shielding ratio is determined based on the shadow area radiation intensity and the non-shadow area radiation intensity.

9. The evaluation device according to claim 8, characterized in that The second calculation module is specifically used for: According to the shadow area percentage and the five parameters of the front / rear side of the single bifacial photovoltaic cell under standard test conditions, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under standard test conditions are calculated respectively; According to the radiation shielding ratio, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell under the standard test conditions, the five parameters of the front shadow area, the five parameters of the front non-shadow area, the five parameters of the rear shadow area, and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shielding scene are calculated; In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the front shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the front non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the front side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated; In the pre-constructed dual current source model of the bifacial photovoltaic cell in the shadow shading scenario, based on the five parameters of the rear shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario and the five parameters of the rear non-shadow area of ​​the single bifacial photovoltaic cell in the shadow shading scenario, the five parameters of the rear side of the single bifacial photovoltaic cell in the shadow shading scenario are calculated.

10. The evaluation device according to claim 6, characterized in that The second determining module is specifically used to: Using the target five parameters of the single bifacial photovoltaic cell in the shadow shading scene, an IV characteristic equation of the single bifacial photovoltaic cell in the shadow shading scene is calculated; Based on the IV characteristic equation of the single bifacial photovoltaic cell, the IV characteristic equation of the bifacial photovoltaic cell string in the shadow shading scene is calculated; Based on the IV characteristic equation of the bifacial photovoltaic cell string, the IV characteristic equation of the bifacial photovoltaic module in the shadow shading scene is calculated; The output power of the bifacial photovoltaic module in a shadow-shading scenario is determined based on the IV characteristic equation of the bifacial photovoltaic module.

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