Photovoltaic module dust accumulation simulation system and dust accumulation amount measurement method

Abstract

The invention discloses a photovoltaic module dust accumulation simulation system and a dust accumulation amount measurement method, and relates to the technical field of photovoltaic dust accumulation evaluation, and the system comprises a measurement system, an environment simulation system and a dust distribution system. The dust is naturally settled and distributed on the surface of the component through the dust distribution system according to the component and particle size distribution of the actual accumulated dust of the photovoltaic power station component. Humidity adjustment, water spraying and oil spraying are carried out through the environment simulation system, accumulated dust and special accumulated dust in different humidity and non-uniform dust accumulation scenes are simulated, the measurement system measures the accumulated dust density, and the accumulated dust density in different dust accumulation scenes is obtained. According to the invention, the problems of large difference and poor representativeness between the simulated dust retention state and the actual dust retention state of the power station are solved, and the accurate measurement of the dust retention density is realized.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic dust accumulation evaluation, and in particular to a photovoltaic component dust accumulation simulation system and a dust accumulation amount determination method. Background Art

[0002] Improving the power generation efficiency and service life of photovoltaic modules is the key to efficient, safe and economical use of solar energy. However, the widespread dust in the natural environment can easily cause dust accumulation on photovoltaic modules. The shading effect and hot spot effect caused by dust accumulation seriously affect the power generation efficiency and service life of photovoltaic panels. When conducting photovoltaic dust accumulation related tests, quickly and accurately obtaining simulated dust accumulation and dust accumulation amount in different scenarios is of great significance for the smooth progress of the test and accurate results.

[0003] Dust accumulation has many effects on photovoltaic modules. It not only reduces the power generation efficiency of photovoltaic modules, but also may cause hot spot effects and affect the service life of the modules. Dust accumulation will reduce the light transmittance of photovoltaic modules and reduce the absorption of solar radiation, thereby reducing power generation efficiency. Studies have shown that the impact of dust on the power generation efficiency of modules can reach 10% to 25%. In some cases, the dust density is inversely proportional to the photovoltaic power generation efficiency. When the dust density is 0.1244 g / m^2, the conversion efficiency of photovoltaic modules decreases by 16.59%; when the dust density reaches 0.898 g / m^2, the conversion efficiency of photovoltaic modules decreases by 54.95%.

[0004] In order to improve the power generation efficiency of photovoltaic modules, the following measures can be taken: optimize the design of photovoltaic modules, such as adjusting the installation inclination, using self-cleaning coatings to prevent particle deposition, so as to improve photovoltaic efficiency and transmittance, while reducing dust accumulation. Improve the cell parameters of photovoltaic modules, optimize the process flow, select high-quality materials, and adopt advanced packaging materials and processes. Use high-efficiency photovoltaic cells, such as high-efficiency monocrystalline silicon cells. Enhance the durability of photovoltaic modules, improve the quality of cells, and adopt new packaging materials and packaging processes. Through the above measures, the impact of dust accumulation on photovoltaic modules can be effectively reduced, and the efficiency and service life of photovoltaic power generation can be improved. However, the impact of dust accumulation on photovoltaic modules cannot be completely solved. At present, the simulation of dust accumulation usually adopts: 1) actual field dust accumulation in photovoltaic power stations; 2) relevant evaluation tests after natural dust accumulation outdoors; 3) artificial dusting indoors.

[0005] The main problems with the above method are: 1) When conducting dust accumulation evaluation tests outdoors, the requirements for weather, equipment, etc. are high, the test cost is high, and the test cycle is long; 2) When measuring dust accumulation outdoors, the test results have poor reproducibility; 3) During indoor tests, artificial dust has problems such as poor uniformity, large differences from natural dust accumulation states, and poor reproducibility. Summary of the invention

[0006] In order to solve the problems existing in the above-mentioned prior art, the present invention provides a photovoltaic module dust accumulation simulation system and a dust accumulation amount measurement method.

[0007] In order to achieve the above purpose, the present invention adopts the following technical scheme: In a first aspect, the present invention provides a photovoltaic module dust accumulation simulation system, including a measurement system, an environmental simulation system, and a dust collection system; The dust collection system includes a blower, a mixing box, a dust collection box, and an air duct, wherein the blower and the mixing box are connected to the dust collection box in sequence through the air duct; The measuring system comprises a photovoltaic module, a reference glass plate, and an electronic balance. The photovoltaic module and the reference glass plate are placed in the dust box. A plurality of reference glass plates are arranged around the photovoltaic module, and each reference glass plate is placed on the electronic balance. The environmental simulation system comprises a humidifier and a nozzle. The outlet of the humidifier is connected to the dust box, and the nozzle is placed above the inside of the dust box.

[0008] As a further improvement of the present invention, a plurality of the nozzles are provided, and the plurality of the nozzles are evenly arranged above the interior of the dust box.

[0009] As a further improvement of the present invention, the spray head is connected to a water spray and / or oil spray device.

[0010] As a further improvement of the present invention, the photovoltaic module is laid flat in the center of the dust box with the front side facing upward. As a further improvement of the present invention, the reference glass plates are placed at the same height as the photovoltaic components around them, and the material and surface state of the multiple reference glass plates are consistent with those of the glass cover plates of the photovoltaic components.

[0011] As a further improvement of the present invention, the weight of the reference glass plate is less than the weight of the photovoltaic module and does not exceed the maximum range of the electronic balance.

[0012] In a second aspect, the present invention provides a method for measuring dust accumulation in a photovoltaic module dust accumulation simulation system, comprising the following steps: According to the actual dust composition and particle size distribution of the photovoltaic power station components, the dust is naturally settled and distributed on the surface of the components through the dust distribution system. The humidity is adjusted, water is sprayed, and oil is sprayed through the environmental simulation system to simulate dust accumulation and special dust accumulation under different humidity and uneven dust accumulation scenes. The measurement system measures the dust density and obtains the dust density under different dust accumulation scenes.

[0013] As a further improvement of the present invention, the following steps are specifically included: Record the readings of the electronic balance respectively to obtain the weight of the reference glass plate before dust accumulation; Pour simulated dust into the mixing box, start the blower, and blow the simulated dust in the mixing box into the dust box through the air duct; when all the dust in the mixing box is blown into the dust box and completely lifted up in the dust box; Turn on the humidifier to humidify the air humidity in the dust box to a specified value to obtain simulated dust accumulation on photovoltaic modules with a specified air humidity; turn on the spray system to spray water to obtain simulated dust accumulation on photovoltaic modules under rainy conditions; turn on the spray system to spray oil to obtain simulated dust accumulation on photovoltaic modules containing oil film and oily dust; Record the electronic balance reading to obtain the weight of the reference glass plate after dust accumulation, and calculate the dust accumulation amount of the reference glass plate. The average dust accumulation amount of the reference glass is the dust accumulation amount of the photovoltaic module.

[0014] As a further improvement of the present invention, the simulated dust is screened and compounded using a standard sieve according to the actual dust composition and particle size distribution of the photovoltaic power station to obtain simulated dust consistent with the actual dust composition and particle size distribution of the photovoltaic power station; the specific scheme is as follows: The dust composition of the power station is composed of quartz 52%, albite 37%, kaolinite 8%, and potassium iron oxalate ore 3%. The dust particle size distribution is between 0.356 and 280.232 μm, of which particles smaller than 14.897 μm account for 30%, and particles smaller than 123.332 μm account for more than 99%. According to the composition of the dust in the power station, the corresponding dust is simulated and prepared, and then the fine dust is sieved out with a sieve with an aperture of 125 μm, and then the sieve is used for secondary screening with a sieve with an aperture of 15 μm. The dust under the sieve and the remaining dust on the sieve are then mixed in a ratio of 3:7 to obtain simulated dust consistent with the actual dust composition and particle size distribution of the photovoltaic power station.

[0015] According to the composition of the power station dust, the corresponding dust is simulated and prepared, and sieved and proportioned through a sieve with a specific aperture to obtain simulated dust that is consistent with the actual dust composition and particle size distribution of the photovoltaic power station. This approach improves the accuracy of the simulation experiment. For example, by simulating the preparation of dust with the same composition as the actual dust, it can ensure that the experimental conditions are highly consistent with the actual environment, thereby more accurately evaluating the impact of dust on the performance of photovoltaic modules. Screening with sieves of different apertures can obtain simulated dust that conforms to the actual dust particle size distribution. This helps to more accurately study the specific impact of dust particles of different particle sizes on the performance of photovoltaic modules.

[0016] Experiments using simulated dust accumulation can evaluate the effects of different cleaning methods and cleaning frequencies on the recovery of photovoltaic module performance. This helps to develop more optimized cleaning strategies and improve the power generation efficiency of photovoltaic power stations. Through simulation experiments, the costs required for different cleaning strategies can be estimated, so as to minimize costs while ensuring the cleaning effect. Based on the results of the simulation experiments, a dust accumulation prediction model can be established to predict the dust accumulation of photovoltaic power stations in the future. This helps photovoltaic power stations to formulate cleaning plans in advance to avoid the impact of dust accumulation on power generation efficiency. According to the composition of power station dust accumulation, the corresponding dust is simulated and prepared, and sieved and proportioned through a sieve with a specific aperture to obtain simulated dust accumulation that is consistent with the actual dust accumulation composition and particle size distribution of the photovoltaic power station. This is of great significance for improving the accuracy of simulation experiments, optimizing the cleaning strategy of photovoltaic modules, promoting the intelligent management of photovoltaic power stations, and promoting technological innovation in photovoltaic power stations.

[0017] As a further improvement of the present invention, when the spray system sprays water to simulate dust accumulation in a rainy day environment, it is ensured that the spray water will not wash away the dust accumulated on the photovoltaic modules and the reference glass plates, and only strip-shaped or spot-shaped dust is formed on the surface of the photovoltaic panels or muddy strip-shaped dust is formed on the frames of the photovoltaic panels.

[0018] As a further improvement of the present invention, the dust accumulation density in different dust accumulation scenarios = (weight of the reference glass plate after dust accumulation - weight of the reference glass plate before dust accumulation) / front surface area of ​​the reference glass plate.

[0019] Compared with the prior art, the present invention has the following advantages: The photovoltaic module dust accumulation simulation system includes a measurement system, an environmental simulation system, and a dust distribution system. According to the composition and particle size distribution of the actual dust accumulation of the photovoltaic power station module, the dust is naturally settled and distributed on the module surface through the dust distribution system. The environmental simulation system is used to adjust the humidity, spray water, and spray oil to simulate the dust accumulation under different humidity and uneven dust accumulation scenes, such as strip-shaped and spot-shaped dust accumulation after rain; for special dust accumulation such as oily dust, the measurement system measures the dust density to obtain the dust density under different dust accumulation scenes. Compared with field testing and long-term monitoring, the photovoltaic module dust accumulation simulation system of the present invention has lower costs, which can greatly save experimental funds and time. The photovoltaic module dust accumulation simulation system of the present invention has the advantages of high precision, high accuracy, high repeatability, high flexibility and low cost, and provides a powerful tool for the dust accumulation research and performance testing of photovoltaic modules. The present invention solves the problem that the simulated dust accumulation is large in difference and poor in representativeness from the actual dust accumulation state of the power station, and realizes the accurate measurement of dust density. There is no need to simulate dust accumulation in a photovoltaic power station or outdoors, and the simulated dust accumulation of a specified dust amount can be obtained in the laboratory. The simulated dust accumulation is highly representative and can simulate dust accumulation in different scenarios; the dust accumulation simulation process and the dust accumulation measurement process are easy to operate and have good reproducibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the system of the present invention. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0022] It should be noted that when an element is referred to as being "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only embodiment.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0024] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0025] The first purpose of the present invention is to provide a photovoltaic module dust accumulation simulation system, including a measurement system, an environmental simulation system, and a dust collection system. The measurement system is composed of a photovoltaic module 1, a reference glass plate 2, and an electronic balance 3; the environmental simulation system is composed of a humidifier 4 and a nozzle 5; and the dust collection system is composed of a blower 6, a mixing box 7, a dust collection box 8, and an air duct 9.

[0026] Among them, the blower 6 and the mixing box 7 are connected to the dust box 8 in turn through the air duct 9; the photovoltaic module 1 and the reference glass plate 2 are placed in the dust box 8, and multiple reference glass plates 2 are arranged on the periphery of the photovoltaic module 1, and each reference glass plate 2 is placed on the electronic balance 3; the outlet of the humidifier 4 is connected to the dust box 8, and the nozzle 5 is placed above the inside of the dust box 8.

[0027] In the photovoltaic module dust accumulation simulation system of the present invention, in the measurement system, the photovoltaic module 1 is used as the tested object to observe and analyze the influence of dust accumulation on its performance. The reference glass plate 2 is placed in the same environment as the photovoltaic module 1 to compare and calibrate the amount of dust accumulation. The glass plate material is transparent, which is convenient for observing and measuring the dust accumulation. The electronic balance 3 is used to accurately measure the mass of dust accumulation on the reference glass plate 2, thereby indirectly inferring the amount of dust accumulation on the photovoltaic module 1.

[0028] Furthermore, in the environmental simulation system, the humidifier 4 is used to adjust the humidity in the dust box 8 to simulate the dust accumulation under different humidity conditions. The nozzle 5 is placed above the dust box 8 to simulate natural phenomena such as rain erosion to observe the performance of the photovoltaic modules after dust accumulation under different conditions.

[0029] In the dust collection system, the blower 6 provides power to blow the dust particles in the mixing box 7 into the dust collection box 8. The mixing box 7 is used to store and mix different types of dust particles to simulate the complex dust accumulation in the actual environment. The dust collection box 8 provides a closed dust accumulation environment for the photovoltaic module 1 and the reference glass plate 2. The air duct 9 connects the blower 6, the mixing box 7 and the dust collection box 8 to ensure that the dust particles can be evenly distributed in the dust collection box 8.

[0030] Furthermore, by precisely controlling the humidifier 4 and the blower 6 and other equipment, the dust accumulation under various environmental conditions can be simulated, thereby improving the accuracy and reliability of the simulation. By using the electronic balance 3 to accurately measure the dust mass on the reference glass plate 2, the amount of dust on the photovoltaic module 1 can be indirectly inferred, avoiding the complexity of directly measuring the surface of the photovoltaic module. Due to the standardization of the system structure and operating procedures, the dust accumulation conditions and environmental parameters of each experiment can be ensured to remain consistent, thereby improving the repeatability of the experiment. By adjusting the humidity of the humidifier 4, the wind speed of the blower 6, and the type and proportion of dust particles in the mixing box 7, the dust accumulation conditions in various actual environments can be simulated to meet different research needs.

[0031] Since the weight of the photovoltaic module 1 exceeds the maximum range of the electronic balance 3, the dust accumulation of the photovoltaic module 1 is indirectly obtained by measuring the dust accumulation of the reference glass plate 2 in the same environment. This method avoids the difficulty of direct measurement. Direct measurement of the dust accumulation of the photovoltaic module may be difficult to achieve due to the excessive weight of the module, and the indirect measurement method cleverly bypasses this problem. The reference glass plate is in the same environment as the photovoltaic module, so its dust accumulation can better reflect the dust accumulation of the photovoltaic module, thereby improving the accuracy of the measurement.

[0032] As an example, a rainy day environment is simulated by a spray system. The spray system sprays water through the nozzle 5 to simulate the dust accumulation in the rainy day environment. The spray water will not wash away the dust on the photovoltaic module 1 and the reference glass plate 2, but only form dust of a specific shape on the surface of the photovoltaic panel. The rainy day environment is one of the common environmental conditions in the operation of photovoltaic power stations. The introduction of the spray system can more realistically simulate the dust accumulation in actual operation. By simulating the rainy day environment, the influence of dust accumulation on the power generation efficiency and heat dissipation performance of photovoltaic modules can be further studied, providing strong support for the operation and maintenance of photovoltaic power stations.

[0033] Multiple nozzles 5 are provided and evenly distributed above the inside of the dust box 8, connected to a water and / or oil spraying device. The uniform arrangement of multiple nozzles can ensure the uniform distribution of dust particles in the dust box, thereby avoiding the situation where there is too much or too little dust accumulation in some places. The uniformity of dust accumulation is crucial to the accuracy of the experimental results, and the uniform arrangement of the nozzles can ensure the reliability and accuracy of the experimental results.

[0034] Preferably, a plurality of the nozzles 5 are provided, and the plurality of the nozzles 5 are evenly arranged above the inside of the dust box 8. The nozzles 5 are connected to a water spraying and / or oil spraying device. The photovoltaic module 1 is laid flat in the center of the dust box 8 with the front side facing upward.

[0035] In the above scheme, the photovoltaic module 1 is laid flat in the center of the dust box 8 with the front side facing upward. In actual installation, the photovoltaic module is usually placed with the front side facing upward, so this setting can more realistically simulate the dust accumulation under actual installation conditions. The front side facing upward setting facilitates the observation and measurement of dust accumulation on the surface of the photovoltaic module, which facilitates subsequent experimental analysis and data processing.

[0036] As a further optional solution, the reference glass plate 2 is placed at the same height as the photovoltaic module 1, and the material and surface state of the multiple reference glass plates are consistent with the glass cover of the photovoltaic module 1. The reference glass plate has the same material and surface state as the photovoltaic module, so its dust accumulation can more accurately reflect the dust accumulation of the photovoltaic module. By comparing the dust accumulation of the reference glass plate and the photovoltaic module, the experimental results can be calibrated and compared, thereby further improving the accuracy and reliability of the experiment.

[0037] Since the weight of the photovoltaic module 1 exceeds the maximum range of the electronic balance 3, the dust accumulation of the photovoltaic module 1 cannot be directly measured by weighing. The dust accumulation of the photovoltaic module 1 is indirectly obtained by measuring the dust accumulation of the reference glass plate 2 in the same environment. Therefore, the weight of the reference glass plate 2 is less than the weight of the photovoltaic module 1 and does not exceed the maximum range of the electronic balance 3.

[0038] As a further optional solution, when the spray system sprays water to simulate dust accumulation in a rainy environment, the spray water will not wash away the dust accumulated on the photovoltaic components 1 and the reference glass plate 2, but will only form strip-shaped or spot-shaped dust on the surface of the photovoltaic panel or muddy strip-shaped dust on the frame of the photovoltaic panel.

[0039] Preferably, the reference glass plate 2 is placed at the same height as the photovoltaic module 1, and the material and surface state of the reference glass plates 2 are consistent with the glass cover of the photovoltaic module 1. The weight of the reference glass plate 2 is less than the weight of the photovoltaic module 1, and does not exceed the maximum range of the electronic balance 3.

[0040] The second object of the present invention is to provide a method for measuring dust accumulation, which specifically comprises the following steps: According to the composition and particle size distribution of the actual dust accumulation of the photovoltaic power station components, the dust is naturally settled and distributed on the surface of the components through the dust distribution system. The humidity is adjusted, water is sprayed, and oil is sprayed through the environmental simulation system to simulate the dust accumulation (strip-shaped and spot-shaped dust accumulation after rain, etc.) and special dust accumulation (oil dust, etc.) under different humidity and uneven dust accumulation scenes. The measurement system measures the dust density to obtain the dust density under different dust accumulation scenes. The present invention solves the problem that the simulated dust is very different from the actual dust accumulation state of the power station and the representativeness is poor, and realizes the accurate measurement of dust density.

[0041] The specific steps are as follows: 1) Lay the photovoltaic module 1 with its front side facing upward in the center of the dust box 8, and place four reference glass plates 2 with the same material and surface condition as the glass cover of the photovoltaic module 1 around it at the same height. Record the front surface areas of the four reference glass plates 2 as S and S as follows: 1 , S 2 , S 3 , S 4 The four reference glass plates 2 are placed on four electronic balances 3 respectively to display the weight of the reference glass plates 2 before and after dust accumulation in real time.

[0042] 2) Record the readings of the four electronic balances 3 respectively to obtain the weight m of the four reference glass plates 2 before dust accumulation 1 、m 2 、m 3 、m 4 ; 3) According to the actual dust composition and particle size distribution of the photovoltaic power station, the dust is screened and compounded using a standard sieve to obtain simulated dust that is consistent with the actual dust composition and particle size distribution of the photovoltaic power station; 4) Pour the simulated dust into the mixing box 7, start the blower 6, and blow the simulated dust in the mixing box 7 into the dust box 8 through the air duct 9. When all the dust in the mixing box 7 is blown into the dust box 8 and completely lifted up in the dust box 8, stop blowing and let it stand for 4 hours.

[0043] 5) Turn on the humidifier 4, humidify the air humidity of the dust box 8 to the specified value, and let it stand for 4 hours to obtain the simulated dust accumulation of the photovoltaic module 1 under the specified air humidity; turn on the spray system to spray water, let it stand for 4 hours after spraying water, and then obtain the simulated dust accumulation of the photovoltaic module 1 under rainy conditions; turn on the spray system to spray oil, let it stand for 4 hours after spraying oil, and then obtain the simulated dust accumulation of the photovoltaic module 1 containing oil film and oil dust. 6) Record the readings of the 4 electronic balances 3 respectively, and obtain the weight m of the 4 reference glass plates 2 after dust accumulation 5 、m 6 、m 7 、m 8 , and calculate the dust accumulation ρ of reference glass plate 2 1 , 2 , 3 , 4 , the average dust accumulation of the reference glass plate 2 is ρ, which is the dust accumulation of the photovoltaic module 1.

[0044] The calculation formula is:

[0045] Embodiment 1: The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0046] like Figure 1 As shown, the photovoltaic module dust accumulation simulation system includes a measurement system, an environmental simulation system, and a dust collection system. The measurement system is composed of a photovoltaic module 1, a reference glass plate 2, and an electronic balance 3; the environmental simulation system is composed of a humidifier 4 and a nozzle 5; and the dust collection system is composed of a blower 6, a mixing box 7, a dust collection box 8, and an air duct 9. According to the composition and particle size distribution of the actual dust accumulation of the photovoltaic power station module, the dust is naturally settled and distributed on the module surface through the dust collection system.

[0047] The steps of the dust accumulation simulation and dust accumulation amount determination method in this embodiment are as follows: 1) Lay the photovoltaic module 1 (2279×1134×35mm) with its front side facing upward in the center of the dust box 8, and place four reference glass plates 2 (200×100×3mm) with the same material and surface condition as the glass cover of the photovoltaic module 1 at the same height around it. The front surface area of ​​the four reference glass plates 2 is 0.02m 2 .

[0048] 2) Four reference glass plates 2 are placed on four electronic balances 3 respectively, and the readings of the four electronic balances 3 are recorded respectively to obtain the weight m of the four reference glass plates 2 before dust accumulation. 1 153.5828g, m 2 153.5064g, m 3 153.5679g, m 4 It is 153.5532g.

[0049] 3) The actual dust composition and particle size distribution provided by the photovoltaic power station show that quartz accounts for 52%, albite accounts for 37%, kaolinite accounts for 8%, and potassium iron oxalate accounts for 3% of the dust composition of the power station. The dust particle size distribution ranges from 0.356 to 280.232μm, of which particles smaller than 14.897μm account for 30%, and particles smaller than 123.332μm account for more than 99%. According to the dust composition of the power station, the corresponding dust is simulated and prepared, and then the fine dust is sieved out with a sieve with an aperture of 125μm, and then the sieve is used for secondary screening with a sieve with an aperture of 15μm. Then, the dust under the sieve and the remaining dust on the sieve are mixed in a ratio of 3:7 to obtain simulated dust consistent with the actual dust composition and particle size distribution of the photovoltaic power station.

[0050] 4) Pour the simulated dust into the mixing box 7, start the blower 6, and blow the simulated dust in the mixing box 7 into the dust box 8 through the air duct 9. When all the dust in the mixing box 7 is blown into the dust box 8 and completely lifted up in the dust box 8, stop blowing and let it stand for 4 hours.

[0051] 5) Turn on the humidifier 4 to humidify the air in the dust box 8 to a relative humidity of 65% and leave it for 4 hours.

[0052] 6) Record the readings of the four electronic balances 3 respectively to obtain the weight m of the four reference glass plates 2 after dust accumulation 5 153.7832g, m 6 153.7060g, m 7 153.7674 g, m 8 is 153.7540 g, and the dust accumulation ρ of reference glass plate 2 is calculated 1 10.02g / m 2 , ρ 2 9.98g / m 2 , ρ 3 9.98g / m 2 , ρ 4 10.04g / m 2 ,, the average dust accumulation of reference glass plate 2 is ρ10.00g / m 2 , which is the amount of dust accumulated on PV module 1.

[0053] Through the above steps, the dust accumulation under the condition of relative humidity of 65% can be obtained as 10g / m 2 Photovoltaic modules 1.

[0054] Embodiment 2: The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0055] like Figure 1 As shown, the photovoltaic module dust accumulation simulation system includes a measurement system, an environmental simulation system, and a dust collection system. The measurement system is composed of a photovoltaic module 1, a reference glass plate 2, and an electronic balance 3; the environmental simulation system is composed of a humidifier 4 and a nozzle 5; and the dust collection system is composed of a blower 6, a mixing box 7, a dust collection box 8, and an air duct 9. According to the composition and particle size distribution of the actual dust accumulation of the photovoltaic power station module, the dust is naturally settled and distributed on the module surface through the dust collection system.

[0056] The steps of the dust accumulation simulation and dust accumulation amount determination method in this embodiment are as follows: 1) Lay the photovoltaic module 1 (2279×1134×35mm) with its front side facing upward in the center of the dust box 8, and place four reference glass plates 2 (200×100×3mm) with the same material and surface condition as the glass cover of the photovoltaic module 1 at the same height around it. The front surface area of ​​the four reference glass plates 2 is 0.02m 2 .

[0057] 2) Four reference glass plates 2 are placed on four electronic balances 3 respectively, and the readings of the four electronic balances 3 are recorded respectively to obtain the weight m of the four reference glass plates 2 before dust accumulation. 1 153.5830g, m 2 153.5069g, m 3 153.5677g, m 4 It is 153.5534g.

[0058] 3) The actual dust composition and particle size distribution provided by the photovoltaic power station show that quartz accounts for 52%, albite accounts for 37%, kaolinite accounts for 8%, and potassium iron oxalate accounts for 3% of the dust composition of the power station. The dust particle size distribution ranges from 0.356 to 280.232μm, of which particles smaller than 14.897μm account for 30%, and particles smaller than 123.332μm account for more than 99%. According to the dust composition of the power station, the corresponding dust is simulated and prepared, and then the fine dust is sieved out with a sieve with an aperture of 125μm, and then the sieve is used for secondary screening with a sieve with an aperture of 15μm. Then, the dust under the sieve and the remaining dust on the sieve are mixed in a ratio of 3:7 to obtain simulated dust consistent with the actual dust composition and particle size distribution of the photovoltaic power station.

[0059] 4) Pour the simulated dust into the mixing box 7, start the blower 6, and blow the simulated dust in the mixing box 7 into the dust box 8 through the air duct 9. When all the dust in the mixing box 7 is blown into the dust box 8 and completely lifted up in the dust box 8, stop blowing and let it stand for 4 hours.

[0060] 5) Turn on the spray system to spray water. The water flow rate should be such that the dust on the components is not washed away. The spraying time is 3 minutes. After the spraying is completed, let it stand for 4 hours. At this time, spot-like simulated dust is obtained.

[0061] 6) Record the readings of the four electronic balances 3 respectively to obtain the weight m of the four reference glass plates 2 after dust accumulation 5 153.7835g, m 6 153.7064g, m 7 153.7679 g, m 8 is 153.7542 g, and the dust accumulation ρ of reference glass plate 2 is calculated 1 10.03g / m 2 , ρ 2 9.98g / m 2 , ρ 3 10.01g / m 2 , ρ 4 10.04g / m 2 , the average dust accumulation of the reference glass plate 2 is ρ10.01g / m 2 , which is the amount of dust accumulated on PV module 1.

[0062] Through the above steps, the dust accumulation in light rainy weather can be obtained. 2 Photovoltaic modules 1.

[0063] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the content of the present invention can be implemented without being limited by any specific theory or mechanism. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention, and these improvements and modifications should also be regarded as the scope of protection of the present invention.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A photovoltaic module dust accumulation simulation system, characterized by: Including measurement system, environmental simulation system, and dust control system; The dust collection system comprises a blower (6), a mixing box (7), a dust collection box (8), and an air duct (9); the blower (6) and the mixing box (7) are connected to the dust collection box (8) in sequence through the air duct (9); The measuring system comprises a photovoltaic module (1), a reference glass plate (2), and an electronic balance (3); the photovoltaic module (1) and the reference glass plate (2) are both placed in the dust box (8); a plurality of reference glass plates (2) are arranged on the periphery of the photovoltaic module (1), and each reference glass plate (2) is placed on the electronic balance (3); The environmental simulation system comprises a humidifier (4) and a nozzle (5); the outlet of the humidifier (4) is connected to a dust box (8), and the nozzle (5) is placed above the inside of the dust box (8).

2. A photovoltaic module dust accumulation simulation system according to claim 1, characterized in that: A plurality of the nozzles (5) are provided, and the plurality of nozzles (5) are evenly arranged above the interior of the dust box (8).

3. A photovoltaic module dust accumulation simulation system according to claim 1, characterized in that: The spray head (5) is connected to a water spray and / or oil spray device.

4. A photovoltaic module dust accumulation simulation system according to claim 1, characterized in that: The photovoltaic assembly (1) is laid flat in the center of the dust box (8) with its front side facing upwards.

5. A photovoltaic module dust accumulation simulation system according to claim 1, characterized in that: The reference glass plates (2) are placed at the same height as the photovoltaic module (1) on all sides, and the material and surface state of the multiple reference glass plates (2) are consistent with those of the glass cover plate of the photovoltaic module (1).

6. A photovoltaic module dust accumulation simulation system according to claim 1, characterized in that: The weight of the reference glass plate (2) is less than the weight of the photovoltaic module (1) and does not exceed the maximum range of the electronic balance (3).

7. A method for measuring dust accumulation in a photovoltaic module dust accumulation simulation system as claimed in claims 1 to 6, characterized in that: The steps include: According to the actual dust composition and particle size distribution of the photovoltaic power station components, the dust is naturally settled and distributed on the surface of the components through the dust distribution system. The humidity is adjusted, water is sprayed, and oil is sprayed through the environmental simulation system to simulate dust accumulation and special dust accumulation under different humidity and uneven dust accumulation scenes. The measurement system measures the dust density and obtains the dust density under different dust accumulation scenes.

8. The dust accumulation measurement method according to claim 7, characterized in that: The specific steps include: Record the readings of the electronic balance (3) respectively to obtain the weight of the reference glass plate (2) before dust accumulation; Pour simulated dust into the mixing box (7), start the blower (6), and blow the simulated dust in the mixing box (7) into the dust box (8) through the air duct (9); when all the dust in the mixing box (7) is blown into the dust box (8) and is completely lifted up in the dust box (8); Turning on the humidifier (4) to humidify the air humidity in the dust box (8) to a specified value, thereby obtaining simulated dust accumulation on the photovoltaic module (1) at the specified air humidity; turning on the spraying system to spray water, thereby obtaining simulated dust accumulation on the photovoltaic module (1) under rainy conditions; The spray system is turned on to spray oil, so as to obtain a photovoltaic module (1) containing oil film and oily dust to simulate dust accumulation; The reading of the electronic balance (3) is recorded to obtain the weight of the reference glass plate (2) after dust accumulation, and the dust accumulation amount of the reference glass plate (2) is calculated. The average dust accumulation amount of the reference glass is the dust accumulation amount of the photovoltaic module (1).

9. The dust accumulation measurement method according to claim 8, characterized in that: The simulated dust is obtained by sieving and compounding the dust according to the actual dust composition and particle size distribution of the photovoltaic power station using a standard sieve to obtain simulated dust consistent with the actual dust composition and particle size distribution of the photovoltaic power station; When the spray system sprays water to simulate dust accumulation in a rainy day environment, it is ensured that the spray water does not wash away the dust accumulated on the photovoltaic module (1) and the reference glass plate (2), and only forms strip-shaped or spot-shaped dust accumulation on the surface of the photovoltaic panel or mud-shaped dust accumulation on the frame of the photovoltaic panel.

10. The dust accumulation measurement method according to claim 8, characterized in that: Dust density in different dust accumulation scenarios = (weight of the reference glass plate after dust accumulation - weight of the reference glass plate before dust accumulation) / front surface area of ​​the reference glass plate.

Images