Photovoltaic module accumulated dust monitoring system and operation method

Abstract

The invention relates to the technical field of photovoltaic dust deposition evaluation, in particular to a photovoltaic module dust deposition monitoring system and an operation method. The system comprises a reference assembly, a test assembly, a data acquisition controller, a dust cover and a cleaning rolling brush, the cleaning rolling brush is arranged on the upper surface of the reference assembly; the dust cover is arranged above the reference assembly and is used for covering the reference assembly; the reference assembly, the dust cover and the cleaning rolling brush are all electrically connected with the data acquisition controller; and the test assembly is electrically connected with the data acquisition controller. According to the invention, full-automatic and real-time monitoring is realized, and the accumulated dust pollution loss can be accurately quantified.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic dust accumulation evaluation, and in particular to a photovoltaic module dust accumulation monitoring system and an operation method thereof. Background Art

[0002] Research shows that the shading effect of dust accumulation on the surface of photovoltaic panels seriously affects the power generation efficiency of photovoltaic panels. In special environments with strong wind and sand and little precipitation, there is more dust accumulation on the battery panels, and the power generation efficiency even drops by 20% - 25%. Therefore, it is of great significance to accurately measure the dust accumulation status of photovoltaic power stations and timely clean the components.

[0003] At present, most photovoltaic power stations use methods such as comparing the power generation of inverters and comparing historical data to evaluate the loss of dust accumulation pollution. This method is relatively rough, with poor accuracy and cannot achieve accurate and rapid measurement. This is because in addition to the power generation loss caused by dust accumulation pollution, there are many factors affecting the inverter power generation data, such as line loss, inverter efficiency, etc.

[0004] In existing real-time dust accumulation monitoring technologies, most use the principle of the optical method. By continuously measuring the light intensity reflected from the glass cover plate of the probe, the optical transmission loss caused by pollutants is calculated, and the power generation loss is indirectly obtained. This method has many environmental interference factors and large calculation errors, and needs to be calibrated for local dust accumulation before use, with complex operations. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems in the prior art, and provide a photovoltaic module dust accumulation monitoring system and an operation method thereof to achieve accurate quantification of the loss of dust accumulation pollution.

[0006] To achieve the above object, the present invention adopts the following technical solutions: In the first aspect, the present invention provides a photovoltaic module dust accumulation monitoring system, including a reference module, a test module, a data acquisition controller, a dust-proof cover, and a cleaning roller brush; the cleaning roller brush is arranged on the upper surface of the reference module; the dust-proof cover is arranged above the reference module for covering the reference module; the reference module, the dust-proof cover, and the cleaning roller brush are all electrically connected to the data acquisition controller; the test module is electrically connected to the data acquisition controller.

[0007] Preferably, the reference module, the dust-proof cover, and the cleaning roller brush are all electrically connected to the data acquisition controller through a reference module data cable; the test module is electrically connected to the data acquisition controller through a test module data cable.

[0008] Preferably, the cleaning roller brush is an electrostatic dust removal roller brush or a mechanical dust removal roller brush.

[0009] In the second aspect, the present invention provides an operation method for a photovoltaic module dust accumulation monitoring system, including the following steps: The data acquisition controller controls the dust cover to open and controls the cleaning brush to clean the reference component. The data acquisition controller collects the backplane center temperature and electrical parameters of the reference component and the test component; and obtains the effective irradiance of the reference component and the test component according to the backplane center temperature and electrical parameters. Obtain the dust pollution loss according to the effective irradiance of the reference component and the test component. The data acquisition controller controls the cleaning brush to clean the reference component again and controls the dust cover to close.

[0010] Preferably, the electrical parameter is short-circuit current or peak power.

[0011] Preferably, the calculation formula for obtaining the dust pollution loss according to the effective irradiance is:

[0012] Wherein, is the dust pollution loss; is the effective irradiance of the reference component; is the effective irradiance of the test component.

[0013] Preferably, the calculation formula for the effective irradiance of the reference component is:

[0014] Wherein, is the short-circuit current of the reference component; is the short-circuit current temperature coefficient of the reference component; is the backplane temperature of the reference component; is the standard test temperature; is the short-circuit current of the reference component under standard test conditions; is the standard test irradiance; Or the calculation formula for the effective irradiance of the reference component is:

[0015] Wherein, is the peak power of the reference component; is the power temperature coefficient of the reference component; is the peak power of the reference component under standard test conditions.

[0016] Preferably, the calculation formula for the effective irradiance of the test component is:

[0017] Wherein, is the short-circuit current of the test component; is the short-circuit current temperature coefficient of the test component; For testing the backplane temperature of the component; For the standard test temperature; For the short - circuit current of the component tested under standard test conditions; For the standard test irradiance; Or the calculation formula for the effective irradiance of the test component is:

[0018] Wherein, For the peak power of the test component; For the power temperature coefficient of the test component; For the peak power of the component tested under standard test conditions.

[0019] Preferably, the standard test conditions include the standard test temperature and the standard test irradiance; the standard test temperature is 25 °C; the standard test irradiance is 1000 W / m 2 .

[0020] Preferably, the reference component and the test component are under the same dust - accumulation environmental conditions.

[0021] Compared with the prior art, the present invention has the following beneficial effects: The present invention synchronously obtains the backplane temperature and electrical parameters of the two components through the data acquisition controller, calculates the difference in effective irradiance based on the temperature compensation model, so as to accurately quantify the loss caused by dust pollution. It is cleaned by the cleaning brush roller, and the external dust is isolated by the dust - proof cover to ensure that the reference component is always in a clean state to form a reference. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 It is a schematic diagram of a photovoltaic module dust - accumulation monitoring system of the present invention.

[0024] Wherein: 1, reference component; 2, test component; 3, data acquisition controller; 4, dust - proof cover; 5, cleaning brush roller; 6, reference component data line; 7, test component data line. DETAILED DESCRIPTION OF THE INVENTION

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more apparent, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. The components of the embodiments of the present invention usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0027] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not require further definition and explanation in subsequent drawings.

[0028] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper", "lower", "horizontal", "inner", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed during use, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive distinction and cannot be construed as indicating or implying relative importance.

[0029] In addition, if the term "horizontal" appears, it does not mean that the component is required to be absolutely horizontal, but it can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but it can be slightly inclined.

[0030] In the description of the embodiments of the present invention, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "connected" are understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] The following further describes the present invention in detail with reference to the accompanying drawings: The first objective of the present invention is to provide a dust accumulation monitoring system for photovoltaic modules, such asFigure 1 As shown in the figure, it includes a reference component 1, a test component 2, a data acquisition controller 3, a dust-proof cover 4, and a cleaning roller brush 5; the cleaning roller brush 5 is arranged on the upper surface of the reference component 1; the dust-proof cover 4 is arranged above the reference component 1 to cover the reference component 1; the reference component 1, the dust-proof cover 4, and the cleaning roller brush 5 are all electrically connected to the data acquisition controller 3 through a reference component data cable 6; the test component 2 is electrically connected to the data acquisition controller 3 through a test component data cable 7.

[0032] Through the comparative design of the reference component 1 and the test component 2, combined with the automated operations of the dust-proof cover 4 and the cleaning roller brush 5, the present invention significantly improves the accuracy and efficiency of dust pollution monitoring. Specifically, before data acquisition, the reference component 1 is cleaned by the cleaning roller brush 5 and isolated from external dust by the dust-proof cover 4 to ensure that it is always in a clean state, forming a reference; the test component 2 accumulates dust synchronously with the photovoltaic power station components to truly reflect the actual pollution degree. The data acquisition controller 3 synchronously obtains the backplane temperature and electrical parameters (such as short-circuit current or peak power) of the two components through the reference component data cable 6 and the test component data cable 7, and calculates the effective irradiance difference based on the temperature compensation model, thereby accurately quantifying the dust pollution loss.

[0033] The cleaning roller brush 5 is an electrostatic dust removal roller brush or a mechanical dust removal roller brush. The electrostatic dust removal roller brush adsorbs dust through an electric field, avoiding abrasion of the component surface caused by physical contact, and is especially suitable for dry and fine dust environments; the mechanical dust removal roller brush strongly removes adherent dust through physical brushing and is suitable for complex pollution scenarios such as sand and rain stains.

[0034] The second object of the present invention is to provide an operation method for a photovoltaic module dust monitoring system, including the following steps: The data acquisition controller 3 controls the dust-proof cover 4 to open and controls the cleaning roller brush 5 to clean the reference component 1; The data acquisition controller 3 collects the backplane center temperature and electrical parameters (short-circuit current or peak power) of the reference component 1 and the test component 2; obtains the effective irradiance of the reference component 1 and the test component 2 based on the backplane center temperature and electrical parameters; Obtains the dust pollution loss based on the effective irradiance of the reference component 1 and the test component 2; The data acquisition controller 3 controls the cleaning roller brush 5 to clean the reference component 1 again and controls the dust-proof cover 4 to close.

[0035] The operation method of the dust accumulation monitoring system for photovoltaic modules proposed by the present invention realizes high-precision automatic measurement of dust pollution loss through an intelligent closed-loop control process. The data acquisition controller 3 precisely controls the coordinated actions of the dust-proof cover 4 and the cleaning brush 5 to ensure that the reference module 1 is always in a standard clean state; at the same time, the backplane temperatures and electrical parameters of the test module 2 and the reference module 1 are synchronously collected, and the effective irradiance difference is calculated based on the temperature compensation algorithm, so as to accurately quantify the dust pollution degree. In particular, the reference module 1 is doubly cleaned before and after data acquisition, effectively eliminating the dust interference that may be introduced during the measurement process and significantly improving the accuracy of the monitoring data.

[0036] The reference module 1 and the test module 2 are in the same dust accumulation environmental conditions, ensuring the scientificity and comparability of the monitoring data.

[0037] The formula for calculating the effective irradiance of the reference module 1 is:

[0038] Where, is the short-circuit current of the reference module 1; is the short-circuit current temperature coefficient of the reference module 1; is the backplane temperature of the reference module 1; is the standard test temperature (25 °C); is the short-circuit current of the reference module 1 under standard test conditions (1000 W / m 2 , 25 °C); is the standard test irradiance (1000 W / m 2 ); Or the formula for calculating the effective irradiance of the reference module 1 is:

[0039] Where, is the peak power of the reference module 1; is the power temperature coefficient of the reference module 1; is the peak power of the reference module 1 under standard test conditions.

[0040] The formula for calculating the effective irradiance of the test module 2 is:

[0041] Where, is the short-circuit current of the test module 2; is the short-circuit current temperature coefficient of the test module 2; is the backplane temperature of the test module 2; is the short-circuit current of the test module 2 under standard test conditions; The calculation formula for the effective irradiance of the test component 2 is as follows:

[0042] Wherein, is the peak power of the test component 2; is the power temperature coefficient of the test component 2; is the peak power of the test component 2 under standard test conditions.

[0043] The calculation formula for obtaining the dust pollution loss based on the effective irradiance is as follows:

[0044] Wherein, is the dust pollution loss; is the effective irradiance of the reference component 1; is the effective irradiance of the test component 2.

[0045] The present invention can flexibly select the current or power calculation path according to actual needs, which not only ensures the reliability of the monitoring data, but also enhances the applicability of the system, providing an accurate data basis for subsequent analysis of the dust pollution loss. In addition, the present invention can avoid a single calculation error through a collaborative calculation mode, making the measurement result more truly reflect the actual irradiance intensity received by the component.

[0046] Example 1: 1) The dust monitoring system is arranged in the area of the photovoltaic power station to be measured, and the test component 2 and the reference component 1 of the photovoltaic power station are dusted in the same natural environment.

[0047] 2) When dust measurement is carried out, the data acquisition controller 3 controls the opening of the dust-proof cover 4 of the reference component, and the cleaning brush 5 of the reference component starts to clean the reference component 1 to keep it in a clean state; wherein, the cleaning brush 5 is an electrostatic dust removal brush.

[0048] 3) The data acquisition controller 3 acquires the backplane center temperature and short-circuit current of the reference component 1 and the test component 2.

[0049] 4) After the data acquisition is completed, the data acquisition controller 3 controls the cleaning brush 5 of the reference component to clean the reference component 1 again, and controls the closing of the dust-proof cover 4 of the reference component.

[0050] 5) The data acquisition controller 3 performs calculations to obtain the dust pollution loss, and the test is completed.

[0051] The calculation formula for the effective irradiance of the reference component 1 is as follows:

[0052] is the short-circuit current of the reference component 1; is the short - circuit current temperature coefficient of the reference module 1 (provided by the module manufacturer, +0.050% / ℃); is the back - panel temperature of the reference module 1; is the standard test temperature (25℃); is the short - circuit current of the reference module 1 under standard test conditions (14.55A); is the standard test irradiance (1000W / m 2 ) The calculation formula for the effective irradiance of the test module 2 is

[0053] where, is the short - circuit current of the test module 2; is the short - circuit current temperature coefficient of the test module 2 (provided by the module manufacturer, +0.050% / ℃); is the back - panel temperature of the test module 2; is the short - circuit current of the test module 2 under standard test conditions (14.55A); The calculation formula for the dust - accumulation pollution loss is:

[0054] is the dust - accumulation pollution loss; is the effective irradiance of the reference module 1; is the effective irradiance of the test module 2.

[0055] The back - panel temperatures of the reference module 1 and the test module 2 collected by the data acquisition controller 3 are both 20℃. The short - circuit current of the reference module 1 is 11.75A, and the short - circuit current of the test module 2 is 10.21A. The calculated dust - accumulation pollution loss SLI is 13%.

[0056] Example 2: 1) The dust - accumulation monitoring system is arranged in the area of the photovoltaic power station to be measured. The test module 2 and the reference module 1 of the photovoltaic power station are dust - accumulated in the same natural environment.

[0057] 2) When measuring the dust - accumulation, the data acquisition controller 3 controls the opening of the dust - proof cover 4 of the reference module, and the cleaning brush 5 of the reference module starts to clean the reference module 1 to keep it in a clean state; among them, the cleaning brush 5 is a mechanical dust - removing brush.

[0058] 3) The data acquisition controller 3 collects the back - panel center temperature and the peak power of the reference module 1 and the test module 2.

[0059] 4) After the data acquisition is completed, the data acquisition controller 3 controls the cleaning brush 5 of the reference module to clean the reference module 1 again and controls the closing of the dust - proof cover 4 of the reference module.

[0060] 5) The data acquisition controller 3 performs calculations to obtain the dust pollution loss, and the test ends.

[0061] The calculation formula for the effective irradiance of the reference component 1 is:

[0062] where, is the peak power of the reference component 1; is the power temperature coefficient of the reference component 1 (provided by the component manufacturer, which is -0.280% / °C); is the peak power of the reference component 1 (600W) under standard test conditions.

[0063] The calculation formula for the effective irradiance of the test component 2 is:

[0064] where, is the peak power of the test component 2; is the power temperature coefficient of the test component 2 (provided by the component manufacturer, which is -0.280% / °C); is the peak power of the test component 2 (600W) under standard test conditions.

[0065] The backplane temperatures of the reference component 1 and the test component 2 collected by the data acquisition controller 3 are both 20°C. The peak power of the reference component 1 is 448W, and the peak power of the test component 2 is 355W. The calculated dust pollution loss SLI is 21%.

[0066] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A dust accumulation monitoring system for a photovoltaic module, characterized in that, It includes a reference component (1), a test component (2), a data acquisition controller (3), a dust-proof cover (4), and a cleaning roller brush (5); the cleaning roller brush (5) is arranged on the upper surface of the reference component (1); the dust-proof cover (4) is arranged above the reference component (1) and is used to cover the reference component (1); the reference component (1), the dust-proof cover (4), and the cleaning roller brush (5) are all electrically connected to the data acquisition controller (3); the test component (2) is electrically connected to the data acquisition controller (3).

2. The dust accumulation monitoring system for a photovoltaic module according to claim 1, wherein The reference component (1), the dust-proof cover (4), and the cleaning roller brush (5) are all electrically connected to the data acquisition controller (3) through a reference component data cable (6); the test component (2) is electrically connected to the data acquisition controller (3) through a test component data cable (7).

3. The dust accumulation monitoring system for a photovoltaic module according to claim 1, wherein The cleaning roller brush (5) is an electrostatic dust removal roller brush or a mechanical dust removal roller brush.

4. The operating method of a dust accumulation monitoring system for a photovoltaic module according to any one of claims 1 to 3, characterized in that, It includes the following steps: The data acquisition controller (3) controls the dust-proof cover (4) to open and controls the cleaning roller brush (5) to clean the reference component (1). The data acquisition controller (3) collects the backplane center temperature and electrical parameters of the reference component (1) and the test component (2); the effective irradiance of the reference component (1) and the test component (2) is obtained based on the backplane center temperature and the electrical parameters. The dust accumulation pollution loss is obtained based on the effective irradiance of the reference component (1) and the test component (2). The data acquisition controller (3) controls the cleaning roller brush (5) to clean the reference component (1) again and controls the dust-proof cover (4) to close.

5. The operation method of a dust accumulation monitoring system for a photovoltaic module according to claim 4, characterized in that, The electrical parameter is short-circuit current or peak power.

6. The operating method of a dust accumulation monitoring system for a photovoltaic module according to claim 5, characterized in that, The calculation formula for obtaining the dust accumulation pollution loss based on the effective irradiance is: Among them, is the loss due to dust accumulation pollution; is the effective irradiance of the reference component (1); is the effective irradiance of the test component (2).

7. The operating method of a dust accumulation monitoring system for a photovoltaic module according to claim 6, characterized in that, The calculation formula for the effective irradiance of the reference component (1) is: Among them, is the short - circuit current of the reference component (1); is the temperature coefficient of the short - circuit current of the reference component (1); is the back - panel temperature of the reference component (1); is the standard test temperature; is the short - circuit current of the reference component (1) under standard test conditions; is the standard test irradiance; Or the calculation formula for the effective irradiance of the reference component (1) is: Wherein, is the peak power of the reference component (1); is the power temperature coefficient of the reference component (1); is the peak power of the reference component (1) under standard test conditions.

8. The operating method of a dust accumulation monitoring system for a photovoltaic module according to claim 6, characterized in that, The calculation formula for the effective irradiance of the test component (2) is: Wherein, is the short - circuit current of the test component (2); is the temperature coefficient of the short - circuit current of the test component (2); is the back - plate temperature of the test component (2); is the standard test temperature; is the short - circuit current of the test component (2) under standard test conditions; is the standard test irradiance; Or the calculation formula for the effective irradiance of the test component (2) is: Among them, is the peak power of the test component (2); is the power temperature coefficient of the test component (2); is the peak power of the test component (2) under standard test conditions.

9. The operating method of a dust accumulation monitoring system for a photovoltaic module according to claim 7 or 8, characterized in that, The standard test conditions include a standard test temperature and a standard test irradiance; the standard test temperature is 25 °C; the standard test irradiance is 1000 W / m 2 .

10. The operating method of a dust accumulation monitoring system for a photovoltaic module according to claim 3, characterized in that The reference component (1) and the test component (2) are under the same dust accumulation environmental conditions.

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