A method and device for improving the power generation efficiency of the back surface of a bifacial cell

Abstract

The application discloses a method and device for improving back power generation efficiency of a bifacial cell, and belongs to the technical field of photovoltaic cells. The method comprises the following steps: obtaining total irradiance intensity and scattered light irradiance intensity of a target reflective component, an inclination angle and a backboard temperature of a target cell component, and a solar elevation angle; calculating an initial inclination angle of the target reflective component based on the inclination angle of the target cell component; calculating a basic adjustment angle of the target reflective component based on the solar elevation angle; calculating a temperature correction coefficient based on the backboard temperature of the target cell component; calculating an irradiance correction coefficient based on the total irradiance intensity and the scattered light irradiance intensity of the target reflective component; determining an angle adjustment mode of the target reflective component based on the total irradiance intensity and the scattered light irradiance intensity, and determining the inclination angle of the target reflective component under different modes. The application can effectively improve the back power generation efficiency of the bifacial cell.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic cell technology and relates to a method and apparatus for improving the power generation efficiency of the back side of a bifacial cell. Background Technology

[0002] TOPCon bifacial photovoltaic cells employ a tunneling oxide layer and polycrystalline silicon passivation structure, exhibiting high bifaciality, high infrared response, and excellent low-light performance, demonstrating significant potential for power generation from the back side. Currently, TOPCon bifacial photovoltaic cells primarily rely on absorbing scattered and reflected light from the ground, limiting their power generation potential. Therefore, increasing the light intensity on the back side of the panel is crucial for improving power generation. Summary of the Invention

[0003] The purpose of this invention is to provide a method and apparatus for improving the power generation efficiency of the back side of a bifacial battery, in order to solve the problem of low power generation efficiency of the back side of existing bifacial batteries.

[0004] To achieve the above objectives, the technical solution of the present invention is as follows:

[0005] In a first aspect, the present invention provides a method for improving the power generation efficiency of the back side of a bifacial battery, comprising:

[0006] Acquire the total irradiance and scattered light irradiance of the target reflective component, the tilt angle and backsheet temperature of the target battery component, and the solar altitude angle;

[0007] The initial tilt angle of the target reflector is calculated based on the tilt angle of the target battery module; the basic adjustment angle of the target reflector is calculated based on the solar altitude angle; the temperature correction coefficient is calculated based on the backsheet temperature of the target battery module; and the irradiance correction coefficient is calculated based on the total irradiance and scattered light irradiance of the target reflector.

[0008] Based on the total irradiance and the scattered light irradiance, the angle adjustment mode of the target reflective component is determined, including: direct mode, scattered mode, combined mode and dormant mode;

[0009] In the integrated mode, the base adjustment angle is corrected based on the temperature correction coefficient and the irradiation correction coefficient to obtain the target adjustment angle, and the target reflective component is adjusted to the target adjustment angle based on the initial tilt angle.

[0010] In direct sunlight mode, the base adjustment angle is corrected based on the temperature correction coefficient to obtain the target adjustment angle, and the target reflective component is adjusted to the target adjustment angle based on the initial tilt angle.

[0011] In scattering mode, adjust the tilt angle of the target reflective component to the preset scattering tilt angle;

[0012] In sleep mode, the target reflective component maintains the tilt angle of the previous moment.

[0013] When the total irradiance is greater than or equal to the preset total irradiance threshold and the proportion of scattered light is greater than or equal to the preset proportion of scattered light threshold, the angle adjustment mode is the comprehensive mode.

[0014] When the total irradiance is greater than or equal to the total irradiance threshold and the proportion of scattered light is less than the proportion of scattered light threshold, the angle adjustment mode is the direct mode.

[0015] When the total irradiance is less than the total irradiance threshold and the proportion of scattered light is greater than or equal to the proportion of scattered light threshold, the angle adjustment mode is the scattering mode.

[0016] When the total irradiance is less than the total irradiance threshold and the proportion of scattered light is less than the proportion of scattered light threshold, the angle adjustment mode is a dormant mode.

[0017] In the integrated mode, the method for correcting the base adjustment angle based on the temperature correction coefficient and the irradiation correction coefficient is as follows:

[0018]

[0019]

[0020]

[0021]

[0022] In the formula, Indicates the tilt angle of the target reflective component. The initial tilt angle of the target reflective component is represented by h, the solar altitude angle is represented by S, and the proportion of scattered light is represented by S. The temperature correction factor is expressed as follows: T represents temperature, G represents total irradiance, D represents scattered light irradiance, and M is the irradiance correction factor.

[0023] In direct sunlight mode, the method for correcting the base adjustment angle based on the temperature correction coefficient is as follows:

[0024]

[0025]

[0026] In the formula, Indicates the tilt angle of the target reflective component. The initial tilt angle of the target reflective component is represented by , and h represents the solar altitude angle. The temperature correction factor is expressed, where T represents temperature.

[0027] Optionally, the tilt angle of the target battery assembly is a fixed value, and the initial tilt angle of the target reflective assembly is equal to the tilt angle of the target battery assembly.

[0028] Optionally, the tilt angle of the target battery assembly is complementary to the solar altitude angle, so that the light always shines directly on the front of the target battery assembly.

[0029] The method further includes determining the installation location of the target reflector in the vicinity of the target battery module based on historical irradiation data of the target battery module's location.

[0030] In a second aspect, the present invention provides an apparatus for improving the power generation efficiency of the back side of a bifacial battery, comprising:

[0031] The sensing component is used to acquire the total irradiance and scattered light irradiance of the target reflective component, the tilt angle and backsheet temperature of the target battery component, and the solar altitude angle.

[0032] The operating mode selection component is used to determine the angle adjustment mode of the target reflective component based on the total irradiance and the scattered light irradiance, including: direct mode, scattered mode, combined mode and sleep mode;

[0033] The angle determination component calculates the initial tilt angle of the target reflector based on the tilt angle of the target battery module; calculates the basic adjustment angle of the target reflector based on the solar altitude angle; calculates the temperature correction coefficient based on the backsheet temperature of the target battery module; calculates the irradiance correction coefficient based on the total irradiance and scattered light irradiance of the target reflector; in the integrated mode, the basic adjustment angle is corrected based on the temperature correction coefficient and the irradiance correction coefficient to obtain the target adjustment angle; in the direct sunlight mode, the basic adjustment angle is corrected based on the temperature correction coefficient to obtain the target adjustment angle.

[0034] The angle adjustment component adjusts the target reflection component to the target adjustment angle of the corresponding mode based on the initial tilt angle in the comprehensive mode and direct mode; in the scattering mode, it adjusts the tilt angle of the target reflection component to the preset scattering tilt angle; in the sleep mode, it keeps the tilt angle of the target reflection component unchanged from the previous moment.

[0035] The reflective surface of the target reflective component is provided with a reflective coating, and the first reflection wavelength range corresponding to the reflective coating matches the first spectral response range of the target battery component backplane.

[0036] The target reflective component includes a plurality of reflective units, the number of which is the same as the number of battery blocks in the target battery component.

[0037] Beneficial effects

[0038] The present invention relates to a method and apparatus for improving the power generation efficiency of the back side of a bifacial battery. It automatically and dynamically adjusts the tilt angle of the reflective component according to different irradiation conditions, thereby improving the light capture efficiency of the back side of the battery module. The apparatus is easy to install and can be directly mounted on existing battery module supports, resulting in low modification costs. The reflected light is evenly distributed, reducing reflections in low-efficiency wavelengths, minimizing localized hot spots, and preventing excessively high operating temperatures of the battery module, further improving power generation efficiency and lifespan. Attached Figure Description

[0039] Figure 1 This is a flowchart of a method for improving the power generation efficiency of the back side of a bifacial battery according to the present invention. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] Example 1

[0042] refer to Figure 1 As shown, a method for improving the power generation efficiency of the back side of a bifacial battery includes:

[0043] The total irradiance and scattered light irradiance of the target reflective component, the tilt angle and backsheet temperature of the target battery component, and the solar altitude angle are obtained.

[0044] The installation location of the target reflector is determined in the vicinity of the target battery module. The initial tilt angle of the target reflector is calculated based on the tilt angle of the target battery module. The base adjustment angle of the target reflector is calculated based on the solar altitude angle. The temperature correction coefficient is calculated based on the backsheet temperature of the target battery module. The irradiance correction coefficient is calculated based on the total irradiance and scattered light irradiance of the target reflector.

[0045] Based on the total irradiance and the scattered light irradiance, the angle adjustment mode of the target reflective component is determined, including: direct mode, scattered mode, combined mode and dormant mode.

[0046] When the total irradiance is greater than or equal to the preset total irradiance threshold and the proportion of scattered light is greater than or equal to the preset proportion of scattered light threshold, the angle adjustment mode is the comprehensive mode.

[0047] When the total irradiance is greater than or equal to the total irradiance threshold and the proportion of scattered light is less than the proportion of scattered light threshold, the angle adjustment mode is the direct mode.

[0048] When the total irradiance is less than the total irradiance threshold and the proportion of scattered light is greater than or equal to the proportion of scattered light threshold, the angle adjustment mode is the scattering mode.

[0049] When the total irradiance is less than the total irradiance threshold and the proportion of scattered light is less than the proportion of scattered light threshold, the angle adjustment mode is a dormant mode.

[0050] In the integrated mode, the base adjustment angle is corrected based on the temperature correction factor and the irradiation correction factor:

[0051]

[0052]

[0053]

[0054]

[0055] In the formula, Indicates the tilt angle of the target reflective component. The initial tilt angle of the target reflective component is represented by h, the solar altitude angle is represented by S, and the proportion of scattered light is represented by S. The expression represents the temperature correction factor, where T represents temperature, G represents total irradiance, D represents scattered light irradiance, and M is the irradiance correction factor. This indicates the basic adjustment angle; it takes into account the reflection of both direct and diffused light.

[0056] In direct sunlight mode, the base adjustment angle is corrected based on the temperature correction factor:

[0057]

[0058] It can maximize the gain of direct light.

[0059] In scattering mode:

[0060] The tilt angle of the reflective component is fixed at a preset scattering tilt angle. In this embodiment, the preset scattering tilt angle is 30°. Based on the results of optical simulation experiments, it is shown that when the tilt angle of the reflective component is less than 30°, the utilization rate of backscattered light will decrease by more than 15%, and there may be partial occlusion between adjacent reflective units, which will further reduce the utilization rate of scattered light. Therefore, the scattering tilt angle is specified to be 30° to ensure the utilization rate of scattered light in the scattering mode, and the scattering mode is more focused on weak light capture.

[0061] In hibernation mode:

[0062] The tilt angle of the reflective component remains unchanged from the previous moment, without consuming additional power.

[0063] In this embodiment, the battery module has a fixed tilt angle of 15°, and the initial tilt angle of the reflective module is the same as that of the battery module. The reflective module includes 132 independently driven reflective units, each of which provides reflected light energy to a corresponding battery cell. In direct mode, the back gain of the battery module is increased by 10.9%-11.3%; in diffused mode, the back gain of the battery module is increased by 6.8%-8.5%; and in combined mode, the back gain of the battery module is increased by 8.6%-10.8%.

[0064] Example 2

[0065] A method for improving the power generation efficiency of the back side of a bifacial battery includes:

[0066] Acquire the total irradiance and scattered light irradiance of the target reflective component, the tilt angle and backsheet temperature of the target battery component, and the solar altitude angle;

[0067] The initial tilt angle of the target reflector is calculated based on the tilt angle of the target battery module; the basic adjustment angle of the target reflector is calculated based on the solar altitude angle; the temperature correction coefficient is calculated based on the backsheet temperature of the target battery module; and the irradiance correction coefficient is calculated based on the total irradiance and scattered light irradiance of the target reflector.

[0068] Based on the total irradiance and the scattered light irradiance, the angle adjustment mode of the target reflective component is determined, including: direct mode, scattered mode, combined mode and dormant mode;

[0069] In the integrated mode, the base adjustment angle is corrected based on the temperature correction coefficient and the irradiation correction coefficient to obtain the target adjustment angle, and the target reflective component is adjusted to the target adjustment angle based on the initial tilt angle.

[0070] In direct sunlight mode, the base adjustment angle is corrected based on the temperature correction coefficient to obtain the target adjustment angle, and the target reflective component is adjusted to the target adjustment angle based on the initial tilt angle.

[0071] In scattering mode, adjust the tilt angle of the target reflective component to the preset scattering tilt angle;

[0072] In sleep mode, the target reflective component maintains the tilt angle of the previous moment.

[0073] In this embodiment, the tilt angle of the battery module changes dynamically with the change of the solar altitude angle, so that the light energy conversion efficiency of the front of the battery module remains optimal, and the initial tilt angle of the reflective component changes synchronously with the tilt angle of the battery module at all times.

[0074] The tilt angle of the target battery module is complementary to the solar altitude angle, ensuring that the sunlight always shines directly on the front of the target battery module.

[0075] Example 3

[0076] An apparatus for improving the power generation efficiency of the back side of a bifacial battery, comprising:

[0077] The sensing component is used to acquire the total irradiance and scattered light irradiance of the target reflective component, the tilt angle and backsheet temperature of the target battery component, and the solar altitude angle.

[0078] The operating mode selection component is used to determine the angle adjustment mode of the target reflective component based on the total irradiance and the scattered light irradiance, including: direct mode, scattered mode, combined mode and sleep mode;

[0079] The angle determination component calculates the initial tilt angle of the target reflector based on the tilt angle of the target battery module; calculates the basic adjustment angle of the target reflector based on the solar altitude angle; calculates the temperature correction coefficient based on the backsheet temperature of the target battery module; calculates the irradiance correction coefficient based on the total irradiance and scattered light irradiance of the target reflector; in the integrated mode, the basic adjustment angle is corrected based on the temperature correction coefficient and the irradiance correction coefficient to obtain the target adjustment angle; in the direct sunlight mode, the basic adjustment angle is corrected based on the temperature correction coefficient to obtain the target adjustment angle.

[0080] The angle adjustment component adjusts the target reflection component to the target adjustment angle of the corresponding mode based on the initial tilt angle in the comprehensive mode and direct mode; in the scattering mode, it adjusts the tilt angle of the target reflection component to the preset scattering tilt angle; in the sleep mode, it keeps the tilt angle of the target reflection component unchanged from the previous moment.

[0081] A reflective coating is provided on the reflective surface of the target reflective component, and the first reflection wavelength range corresponding to the reflective coating matches the first spectral response range of the target battery component backplane.

[0082] In this embodiment, based on experimental data of photoelectric response efficiency of TOPCon batteries in different spectra, it is known that TOPCon batteries have a high response in the 700–1100nm infrared band. In order to improve the light capture capability in the infrared band, the reflective surface of the reflective component is provided with an aluminum-based nano-silica composite high-reflectivity coating, which has a reflectivity of ≥95% in the 700–1100nm infrared band and a reflectivity of ≤40% in the ultraviolet band. This accurately matches the light energy to the highest response range on the back of the TOPCon battery component, thereby improving the power generation efficiency.

[0083] In summary, the method and apparatus for improving the power generation efficiency of the back side of a bifacial battery according to the present invention automatically and dynamically adjusts the tilt angle of the reflective component according to different irradiation conditions, thereby improving the light energy capture efficiency of the back side of the battery module; the apparatus is easy to install and can be directly installed on the existing battery module bracket, with low modification costs; the reflected light is evenly distributed, reducing reflection of low-efficiency wavelengths, reducing local hot spots, and avoiding excessively high operating temperatures of the battery module, thereby further improving power generation efficiency and service life.

[0084] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for improving the power generation efficiency of the back side of a bifacial battery, characterized in that, include: Acquire the total irradiance and scattered light irradiance of the target reflective component, the tilt angle and backsheet temperature of the target battery component, and the solar altitude angle; The initial tilt angle of the target reflective component is calculated based on the tilt angle of the target battery component. The basic adjustment angle of the target reflective component is calculated based on the solar elevation angle. Calculate the temperature correction factor based on the backsheet temperature of the target battery module; calculate the irradiance correction factor based on the total irradiance and scattered light irradiance of the target reflective module; Based on the total irradiance and the scattered light irradiance, the angle adjustment mode of the target reflective component is determined, including: direct mode, scattered mode, combined mode and dormant mode; In the integrated mode, the base adjustment angle is corrected based on the temperature correction coefficient and the irradiation correction coefficient to obtain the target adjustment angle, and the target reflective component is adjusted to the target adjustment angle based on the initial tilt angle. In direct sunlight mode, the base adjustment angle is corrected based on the temperature correction coefficient to obtain the target adjustment angle, and the target reflective component is adjusted to the target adjustment angle based on the initial tilt angle. In scattering mode, adjust the tilt angle of the target reflective component to the preset scattering tilt angle; In sleep mode, the target reflective component maintains the tilt angle of the previous moment.

2. The method for improving the power generation efficiency of the back side of a bifacial battery according to claim 1, characterized in that, When the total irradiance is greater than or equal to the preset total irradiance threshold and the proportion of scattered light is greater than or equal to the preset proportion of scattered light threshold, the angle adjustment mode is the comprehensive mode. When the total irradiance is greater than or equal to the total irradiance threshold and the proportion of scattered light is less than the proportion of scattered light threshold, the angle adjustment mode is the direct mode. When the total irradiance is less than the total irradiance threshold and the proportion of scattered light is greater than or equal to the proportion of scattered light threshold, the angle adjustment mode is the scattering mode. When the total irradiance is less than the total irradiance threshold and the proportion of scattered light is less than the proportion of scattered light threshold, the angle adjustment mode is a dormant mode.

3. The method for improving the power generation efficiency of the back side of a bifacial battery according to claim 2, characterized in that, In the integrated mode, the method for correcting the base adjustment angle based on the temperature correction coefficient and the irradiation correction coefficient is as follows: In the formula, Indicates the tilt angle of the target reflective component. The initial tilt angle of the target reflective component is represented by h, the solar altitude angle is represented by S, and the proportion of scattered light is represented by S. The temperature correction factor is expressed as follows: T represents temperature, G represents total irradiance, D represents scattered light irradiance, and M is the irradiance correction factor.

4. The method for improving the power generation efficiency of the back side of a bifacial battery according to claim 2, characterized in that, In direct sunlight mode, the method for correcting the base adjustment angle based on the temperature correction coefficient is as follows: In the formula, Indicates the tilt angle of the target reflective component. The initial tilt angle of the target reflective component is represented by , and h represents the solar altitude angle. The temperature correction factor is expressed, where T represents temperature.

5. The method for improving the power generation efficiency of the back side of a bifacial battery according to claim 1, characterized in that, The tilt angle of the target battery assembly is a fixed value, and the initial tilt angle of the target reflective assembly is equal to the tilt angle of the target battery assembly.

6. The method for improving the power generation efficiency of the back side of a bifacial battery according to claim 1, characterized in that, The tilt angle of the target battery assembly is complementary to the solar altitude angle, ensuring that the light always shines directly on the front of the target battery assembly.

7. The method for improving the power generation efficiency of the back side of a bifacial battery according to claim 1, characterized in that, The method further includes determining the installation location of the target reflector in the vicinity of the target battery module based on historical irradiation data of the target battery module's location.

8. A device for improving the power generation efficiency of the back side of a bifacial battery, characterized in that, include: The sensing component is used to acquire the total irradiance and scattered light irradiance of the target reflective component, the tilt angle and backsheet temperature of the target battery component, and the solar altitude angle. The operating mode selection component is used to determine the angle adjustment mode of the target reflective component based on the total irradiance and the scattered light irradiance, including: direct mode, scattered mode, combined mode and sleep mode; The angle determination component calculates the initial tilt angle of the target reflector based on the tilt angle of the target battery module; calculates the basic adjustment angle of the target reflector based on the solar altitude angle; calculates the temperature correction coefficient based on the backsheet temperature of the target battery module; calculates the irradiance correction coefficient based on the total irradiance and scattered light irradiance of the target reflector; in the integrated mode, the basic adjustment angle is corrected based on the temperature correction coefficient and the irradiance correction coefficient to obtain the target adjustment angle; in the direct sunlight mode, the basic adjustment angle is corrected based on the temperature correction coefficient to obtain the target adjustment angle. The angle adjustment component adjusts the target reflection component to the target adjustment angle of the corresponding mode based on the initial tilt angle in the comprehensive mode and direct mode; in the scattering mode, it adjusts the tilt angle of the target reflection component to the preset scattering tilt angle; in the sleep mode, it keeps the tilt angle of the target reflection component unchanged from the previous moment.

9. The apparatus for improving the power generation efficiency of the back side of a bifacial battery according to claim 8, characterized in that, The reflective surface of the target reflective component is provided with a reflective coating, and the first reflection wavelength range corresponding to the reflective coating matches the first spectral response range of the target battery component backplane.

10. The apparatus for improving the power generation efficiency of the back side of a bifacial battery according to claim 8, characterized in that, The target reflective component includes a plurality of reflective units, the number of which is the same as the number of battery blocks in the target battery component.

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