Variable-frequency ash removal device for improving photovoltaic power generation efficiency

Abstract

The invention discloses a variable-frequency ash removal device for improving photovoltaic power generation efficiency, and a control system of the variable-frequency ash removal device can dynamically adjust the output frequency and amplitude of a signal generator according to cleaning requirements. Particularly, when different types of dust are cleaned, the system can automatically adjust the vibration frequency, so that the cleaning process is more accurate. Large-particle dust is effectively removed through low-frequency and large-amplitude vibration, and small-particle dust is finely cleaned through high-frequency micro-vibration. The dynamic adjustment of the frequency and the amplitude ensures that each dust type can be thoroughly removed, and the problem of poor effect caused by fixed frequency in a traditional cleaning method is avoided.

Description

Technical Field

[0001] The present invention belongs to the field of photovoltaic dust cleaning, and in particular, relates to a variable frequency dust cleaning device for improving photovoltaic power generation efficiency. Background Art

[0002] Dust coverage in the air has a significant impact on the energy conversion of photovoltaic panels. Photovoltaic panels convert sunlight into electricity. The accumulation of dust will reduce the light transmittance of photovoltaic panels, thereby affecting their power generation efficiency. Especially in dry and rainy areas, the dust accumulation problem is more serious, resulting in a decrease in power generation. Therefore, dust is one of the key factors affecting the power generation of photovoltaic power stations.

[0003] There have been a lot of studies at home and abroad on the dust cleaning of large photovoltaic power stations. The main methods of cleaning the dust on the surface of photovoltaic panels are: manual cleaning, compressed air blowing, mechanical vibration, and dust suppression coating.

[0004] Although manual cleaning is the most intuitive and traditional cleaning method, it usually uses a brush, cleaning cloth or other tools to manually remove surface dust. Its advantages are that it can clean stubborn dust that is difficult to remove, and can perform fine cleaning on each photovoltaic module. However, manual cleaning is inefficient and labor-intensive, and in large-scale photovoltaic power stations, manual cleaning will bring high costs and considerable risks, especially in high temperature or high altitude environments;

[0005] Compressed air blowing is to quickly blow away the dust on the photovoltaic panels by jetting high-pressure air. Its advantages are easy operation and fast speed, especially suitable for light dust. Compressed air blowing can not only avoid surface scratches that may be caused by contact cleaning, but it is less effective for dust with heavy dust accumulation or strong adhesion. In addition, air blowing sometimes causes secondary pollution of dust, especially in areas with strong winds.

[0006] Mechanical vibration is to loosen the dust on the surface of the photovoltaic panel by the vibration force generated by the vibration device, so that it falls off. This method is more effective for cleaning large areas of dust accumulation, and can remove most of the dust on the surface with high efficiency. However, mechanical vibration may cause a certain degree of wear and tear on the surface of the photovoltaic panel, especially for high-efficiency photovoltaic panels, long-term use may cause minor damage, affecting the service life of the panel;

[0007] Dust suppression coating is a special dust-resistant coating applied to the surface of photovoltaic panels to reduce the adhesion of dust. This coating has self-cleaning properties and can prevent dust accumulation to a certain extent, reducing the frequency of cleaning. However, the cost of dust suppression coating is high, and the effect is affected by weather conditions and usage time. Over time, the dust-proof effect of the coating will gradually decrease.

[0008] The dust cleaning problem of photovoltaic power stations is directly related to power generation efficiency and equipment life. Although existing cleaning methods can remove dust to a certain extent, they all have problems such as low efficiency, high cost, and potential damage to equipment.

[0009] In view of this, the present invention is proposed. Summary of the invention

[0010] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a variable frequency dust cleaning device for improving the efficiency of photovoltaic power generation, thereby solving the problems raised in the above-mentioned background technology.

[0011] In order to solve the above technical problems, the basic concept of the technical invention adopted by the present invention is:

[0012] A variable frequency dust cleaning device for improving photovoltaic power generation efficiency comprises: a signal generator for sending a variable frequency signal;

[0013] A power amplifier, connected to the signal generator, for amplifying the frequency conversion signal to a required power;

[0014] Fixed bracket;

[0015] The transducer is fixedly mounted on the flat or curved surface of the plate through a fixing bracket and connected to a power amplifier to convert the power signal into vibration and act on the surface of the photovoltaic or thermal plate;

[0016] A controller with a control system, the control system is used to adjust the output frequency of the signal generator and control the working state of the transducer. The control system can gradually reduce the frequency of the signal generator within a certain period of time to complete a dust cleaning process.

[0017] Optionally, the signal generator can generate a variable frequency signal with a frequency of 10kHz to 20kHz; the power amplifier can amplify the frequency signal power output by the signal generator to 50W to 200W; the control system can control the frequency of the signal generator to gradually decrease from 20kHz to 10kHz within 30 seconds.

[0018] Optionally, a visual monitoring device is further included to monitor the dust distribution on the surface of the photovoltaic or solar thermal panel in real time; the visual monitoring device detects dust in uncleaned areas on the panel surface through an image processing algorithm and transmits a feedback signal to a control system; the control system automatically adjusts the vibration frequency and amplitude according to the feedback signal to ensure that the dust is completely removed, and the steps are as follows:

[0019] Use visual monitoring equipment to scan the surface of photovoltaic or solar thermal panels in real time to obtain the distribution image of dust on the panel surface. Then, use image processing algorithms to analyze the acquired image, identify the dust accumulation area, and generate dust distribution data. Based on the dust distribution data, evaluate the cleanliness level and determine which areas need further cleaning.

[0020] Based on the dust distribution detection results, the visual monitoring equipment transmits relevant feedback signals to the control system. The feedback signals include the location and area of ​​the uncleaned dust area and the degree of dust accumulation that needs further cleaning;

[0021] After receiving the feedback signal, the control system analyzes the areas that are not cleaned enough and automatically adjusts the vibration frequency and amplitude to ensure that the dust in the uncleaned areas can be completely removed. Specifically, the appropriate frequency is automatically selected according to the size and adhesion of the dust particles. Larger dust particles may require lower frequencies and larger amplitudes to remove, while smaller dust particles are cleaned through high-frequency tiny vibrations. For stubborn dust areas that are difficult to remove, the control system can increase the amplitude so that the transducer produces stronger vibrations, thereby activating the dust particles and moving them to the standing wave nodes.

[0022] Optionally, the steps of analyzing the acquired image by an image processing algorithm, identifying the dust accumulation area, and generating dust distribution data are as follows:

[0023] Input image I(x, y), where x and y represent the pixel coordinates in the image. Each pixel of the image can have three components: red, green, and blue. Then, through the grayscale process, the image is converted into a single-channel image G(x, y). The calculation formula is as follows: G(x, y) = 0.299·R(x, y) + 0.587·G(x, y) + 0.114·B(x, y) where G(x, y) are the red, green, and blue components of the (x, y)th pixel in the image respectively;

[0024] Use the threshold segmentation method to separate the dust area in the image from the background. Select an appropriate threshold T and convert the grayscale image into a binary image B(x, y), where the dust area is marked as 1 and the background is 0. For each pixel G(x, y), if its grayscale value is greater than the threshold T, it means that the pixel is a dust area, otherwise it is the background. The binary formula is:

[0025] By extracting the features of the dust area, the dust accumulation area is determined and the edge of the dust area in the image is detected by the Sobel operator. The expression is: G x (x,y)=B(x+1,y)-B(x-1,y),G y(x,y)=B(x,y+1)-B(x,y-1) is the gradient of the image in the x and y directions, and C(x,y) represents the edge strength of the dust area;

[0026] The image after edge detection is analyzed by the connected region labeling method to calculate the dust region aggregation degree A. First, let the detected dust region set be D, where each connected region R i satisfy: The aggregation degree A can be expressed by the ratio of the area to the edge density: The calculations of the area and boundary perimeter are: Indicates region R i the boundaries of;

[0027] The dust distribution map D is generated through the above aggregation and connected area marking results. map (x, y), its value represents the dust density of each pixel, and its expression is: is the indicator function. If (x, y) belongs to the dust region R i , then it is 1, otherwise it is 0, A i For region R i degree of aggregation.

[0028] Optionally, the cleanliness of each area is evaluated by first calculating the total area A of the dusty area. total and the total area of ​​the photovoltaic panels A panel Compare and get the total cleanliness. Then, for each area R i , calculate its cleanliness: in, and The introduction of is to reduce the weight of areas with stronger thickness and adhesion so that the system can automatically adjust the cleaning strategy;

[0029] Based on the cleanliness assessment results, the areas that need further cleaning are marked. All areas where the cleanliness is below the preset threshold R i The areas that need to be cleaned will be selected, and the control system will adjust the cleaning strategy based on this information.

[0030] Optionally, the control system can adjust the frequency and amplitude of the vibration according to the size of the dust particles and the cleaning requirements; for larger dust particles, the system increases the amplitude and increases the vibration intensity; for smaller dust particles, the system adjusts the frequency to achieve fine cleaning, the steps are:

[0031] The particle image of the dust area is obtained by the acquired image, and then, according to the area A of the dust area i , set a threshold A threshold To classify particles, the expression is: Classify the particles into large and small particles through threshold classification, and then adjust the frequency and amplitude of the vibration according to the size of the dust particles;

[0032] According to the adhesion of the particles, the frequency and amplitude of the vibration are fine-tuned, and the expression is: A adjusted =A new ·(1+γ·C i ),f adjusted =f new ·(1-δ·C i ), where γ and δ are adjustment coefficients, which respectively control the increase or decrease of amplitude and frequency in the area with strong adhesion, A adjusted and f adjusted are the adjusted frequency and amplitude, respectively;

[0033] When all dust areas are cleared, the system calculates the total dust area A total Determine whether to stop cleaning.

[0034] Optionally, when adjusting the frequency and amplitude of vibration according to the size of dust particles, the amplitude of vibration is increased for large dust particles, and the expression is: For small dust particles, the frequency of vibration is adjusted as follows: Among them, f base is the fundamental frequency; β is the adjustment coefficient; A i is the area of ​​the current dust region; A max is the maximum area of ​​the large particle, A base is the basic amplitude; α is the amplification factor; A max is the maximum area of ​​the large particle; A i is the area of ​​the current dust region.

[0035] A variable frequency dust cleaning device for improving the efficiency of photovoltaic power generation also includes an environmental sensor for monitoring ambient temperature, humidity, and wind speed; a control system dynamically adjusts the working state of the dust cleaning device according to the monitored environmental data, including vibration frequency, amplitude, and cleaning cycle, to adapt to different climatic conditions; when the temperature is too high or the humidity is too high, the control system automatically adjusts the cleaning intensity to avoid excessive dust adhesion or damage.

[0036] After adopting the above technical invention, the present invention has the following beneficial effects compared with the prior art. Of course, any product implementing the present invention does not necessarily need to achieve all the advantages described below at the same time:

[0037] 1. The control system of the present invention can dynamically adjust the output frequency and amplitude of the signal generator according to the cleaning requirements. In particular, when cleaning different types of dust, the system can automatically adjust the vibration frequency to make the cleaning process more precise. Larger particles of dust are effectively removed by low-frequency and large-amplitude vibrations, while smaller particles are finely cleaned by high-frequency micro-vibrations. This dynamic adjustment of frequency and amplitude ensures that each type of dust can be thoroughly removed, avoiding the poor effect caused by fixed frequency in traditional cleaning methods.

[0038] 2. The device can efficiently remove dust on the surface of photovoltaic panels or solar thermal panels in a short time by converting the power signal into vibration through the transducer and acting on the surface of the photovoltaic panel or solar thermal panel. Compared with traditional cleaning methods, this variable frequency dust cleaning device for improving photovoltaic power generation efficiency can greatly improve the cleaning efficiency. The variable frequency signal with gradually decreasing frequency can make the dust concentrate at the node of the standing wave, forming an effective dust removal path, thereby ensuring thorough cleaning.

[0039] 3. A variable frequency dust cleaning device for improving photovoltaic power generation efficiency amplifies the variable frequency signal to the required power through a power amplifier to ensure that the vibration energy is accurately transmitted to the cleaning surface. The efficient vibration output of the device ensures the cleaning effect while avoiding unnecessary energy waste. Compared with other cleaning methods, this device can provide the same or more efficient cleaning effect while saving energy.

[0040] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings described below are only some embodiments. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0042] Figure 1 A schematic diagram of the frequency variation of a variable frequency dust cleaning device for improving photovoltaic power generation efficiency with a period;

[0043] Figure 2 A frequency conversion dust cleaning device for improving photovoltaic power generation efficiency is placed on the main plane view of a plate;

[0044] Figure 3 A frequency conversion dust cleaning device for improving photovoltaic power generation efficiency is placed on a side view of a plate plane;

[0045] Figure 4 A comparison curve diagram of cleaning effects in a variable frequency dust cleaning device for improving photovoltaic power generation efficiency;

[0046] Figure 5A diagram showing the effect of particle size on cleaning effect in a variable frequency dust cleaning device for improving photovoltaic power generation efficiency;

[0047] Figure 6 This is one of the three-dimensional structural schematic diagrams of the handheld dust cleaning device of Example 2;

[0048] Figure 7 This is the second schematic diagram of the three-dimensional structure of the handheld dust cleaning device in Example 2.

[0049] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0050] 1. Transducer; 2. Fixed bracket; 3. Plate surface; 4. Control box; 5. Hand-held rod; 6. Connecting part; 7. Display screen; 8. Placement slot; 9. Plate body; 10. Camera.

[0051] It should be noted that these drawings and textual descriptions are not intended to limit the conceptual scope of the present invention in any way, but are intended to illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0052] The present invention will now be described in further detail with reference to the accompanying drawings.

[0053] Example 1: Please refer to Figure 1-2 As shown, in this embodiment, a variable frequency dust cleaning device for improving photovoltaic power generation efficiency is provided, including a signal generator for sending a variable frequency signal;

[0054] A power amplifier, connected to the signal generator, for amplifying the frequency conversion signal to a required power;

[0055] Fixed bracket 2;

[0056] The transducer 1 is fixedly mounted on the flat surface 3 or the curved surface of the plate through a fixing bracket 2 and connected to a power amplifier to convert the power signal into vibration and act on the surface of the photovoltaic or thermal plate 3;

[0057] The controller 4 is provided with a control system, and the control system is used to adjust the output frequency of the signal generator and control the working state of the transducer 1. The control system can gradually reduce the frequency of the signal generator within a certain period of time to complete a dust cleaning process.

[0058] The present invention is mainly used for cleaning the surface of photovoltaic or thermal panels 3, glass mirrors, pipe walls and other planes or curved surfaces. The present invention mainly includes a signal generator, a power amplifier, a transducer 1 and a corresponding control system. The signal generator sends a variable frequency signal to the power amplifier, and the power amplifier outputs power to the transducer 1, which is fixedly mounted on the surface of the plane or curved surface. According to the Chladni figure principle, the vibration acting on the plane or curved surface will cause the particles to gather at the nodes of the standing wave. When the frequency of the transducer 1 gradually decreases, as the vibration frequency decreases, the longer the period, the wave speed remains unchanged due to the material, and the wavelength becomes longer, that is, the sparser the Chladni figure, which is manifested as the particles moving away from the vibration source. This is the principle of variable frequency cleaning. Using this principle to clean the dust on the photovoltaic or thermal panels 3 and other surfaces is simple, convenient and easy to maintain.

[0059] In this embodiment, the signal generator can generate a variable frequency signal with a frequency of 10kHz to 20kHz; the power amplifier can amplify the frequency signal power output by the signal generator to 50W to 200W; the control system can control the frequency of the signal generator to gradually decrease from 20kHz to 10kHz within 30 seconds. The frequency of the signal generator is controlled to decrease from 20kHz to 10kHz within 30 seconds, and one cleaning is completed. According to the size of the photovoltaic or solar thermal plate 3, multiple cleanings are reasonably set to complete the dust cleaning work on the surface of the entire plate 3.

[0060] See also Figure 6-7 As shown, embodiment 2: a handheld dust cleaning device, comprising a handheld rod 5, a connecting portion (6) above the handheld rod 5, a display screen 7 and a plurality of control buttons are arranged above the connecting portion 6, a placement slot 8 is provided in the middle part of one side of the connecting portion 6, two plates 9 are connected to its edge, a transducer 1 is fixedly connected to the bottom of the top plate 9, a controller 4 is arranged inside the placement slot 9, and the transducer 1 and the controller 4 are connected via a signal line, and a camera 10 is also fixedly connected to one side of the plate 9. By using the handheld dust cleaning device, personnel can clamp the dust cleaning device at different positions on the plate plane according to the situation, and the plate plane is located between the transducer 1 and the bottom plate 9. The handheld setting also facilitates subsequent personnel to adjust its position, and real-time data can be monitored through the display screen 7.

[0061] The present embodiment also includes a visual monitoring device for real-time monitoring of dust distribution on the surface of the photovoltaic or solar thermal panel; the visual monitoring device detects dust in uncleaned areas on the panel surface through an image processing algorithm and transmits a feedback signal to a control system; the control system automatically adjusts the vibration frequency and amplitude according to the feedback signal to ensure that the dust is completely removed, and the steps are as follows:

[0062] Use visual monitoring equipment such as cameras, infrared sensors or laser scanners to scan the surface of photovoltaic or solar thermal panels in real time to obtain dust distribution images on the panel surface. Then, use image processing algorithms to analyze the acquired images, identify dust accumulation areas, and generate dust distribution data. Based on the dust distribution data, evaluate the degree of cleanliness and determine which areas need further cleaning.

[0063] Based on the dust distribution detection results, the visual monitoring equipment transmits relevant feedback signals to the control system. The feedback signals include information such as the location and area of ​​the uncleaned dust area and the degree of dust accumulation that needs further cleaning;

[0064] After receiving the feedback signal, the control system analyzes the areas that are not cleaned enough and automatically adjusts the vibration frequency and amplitude to ensure that the dust in the uncleaned areas can be completely removed. Specifically, the appropriate frequency is automatically selected according to the size and adhesion of the dust particles. Larger dust particles may require lower frequencies and larger amplitudes to be removed, while smaller dust particles are cleaned through high-frequency tiny vibrations. For stubborn dust areas that are difficult to remove, the control system can increase the amplitude so that the transducer 1 produces stronger vibrations, thereby activating the dust particles and moving them to the standing wave nodes.

[0065] In this embodiment, the steps of analyzing the acquired image, identifying the dust accumulation area, and generating dust distribution data by using an image processing algorithm are as follows:

[0066] Input image I(x, y), where x and y represent the pixel coordinates in the image. Each pixel of the image can have three components: red, green, and blue RGB. Then, through the grayscale process, the image is converted into a single-channel image G(x, y). The calculation formula is as follows: G(x, y) = 0.299·R(x, y) + 0.587·G(x, y) + 0.114·B(x, y) where G(x, y) are the red, green, and blue components of the (x, y)th pixel in the image respectively;

[0067] Use the threshold segmentation method to separate the dust area in the image from the background. Select an appropriate threshold T and convert the grayscale image into a binary image B(x, y), where the dust area is marked as 1 and the background is 0. For each pixel G(x, y), if its grayscale value is greater than the threshold T , it means that the pixel is a dust area, otherwise it is a background. The binary formula is:

[0068] By extracting the features of the dust area, the dust accumulation area is determined and the edge of the dust area in the image is detected by the Sobel operator. The expression is: G x (x,y)=B(x+1,y)-B(x-1,y),Gy (x,y)=B(x,y+1)-B(x,y-1) is the gradient of the image in the x and y directions, and C(x,y) represents the edge strength of the dust area;

[0069] The image after edge detection is analyzed by the connected region labeling method to calculate the dust region aggregation degree A. First, let the detected dust region set be D, where each connected region R i satisfy: The concentration A It can be expressed by the ratio of the area to the edge density: The calculations of the area and boundary perimeter are: Indicates region R i the boundaries of;

[0070] The dust distribution map D is generated through the above aggregation and connected area marking results. map (x, y), its value represents the dust density of each pixel, and its expression is: is the indicator function. If (x, y) belongs to the dust region R i , then it is 1, otherwise it is 0, A i For region R i degree of aggregation.

[0071] In this embodiment, when evaluating the cleanliness of each area, first, the total area A of the dust area is calculated. total and the total area of ​​the photovoltaic panels A panel Compare and get the total cleanliness. Then, for each area R i , calculate its cleanliness: in, and The introduction of is to reduce the weight of areas with stronger thickness and adhesion so that the system can automatically adjust the cleaning strategy;

[0072] Based on the cleanliness assessment results, the areas that need further cleaning are marked. All areas where the cleanliness is below the preset threshold R i The areas that need to be cleaned will be selected, and the control system will adjust the cleaning strategy based on this information.

[0073] In this embodiment, the control system can adjust the frequency and amplitude of the vibration according to the size of the dust particles and the cleaning requirements; for larger dust particles, the system increases the amplitude and increases the vibration intensity; for smaller dust particles, the system adjusts the frequency to achieve fine cleaning, and the steps are as follows:

[0074] The particle image of the dust area is obtained by the acquired image, and then, according to the area A of the dust area i , set a threshold Athreshold To classify particles, the expression is: Classify the particles into large and small particles through threshold classification, and then adjust the frequency and amplitude of the vibration according to the size of the dust particles;

[0075] According to the particle adhesion, the boundary complexity C i Evaluate and fine-tune the frequency and amplitude of vibration, the expression is: A adjusted =A new ·(1+γ·C i ),f adjusted =f new ·(1-δ·C i ), where γ and δ are adjustment coefficients, which respectively control the increase or decrease of amplitude and frequency in the area with strong adhesion, A adjusted and f adjusted are the adjusted frequency and amplitude, respectively;

[0076] When all dust areas are cleared, the system calculates the total dust area A total Determine whether to stop cleaning.

[0077] In this embodiment, when the frequency and amplitude of the vibration are adjusted according to the size of the dust particles, the amplitude of the vibration is increased for large dust particles, and the expression is: For small dust particles, the frequency of vibration is adjusted as follows: Among them, f base is the fundamental frequency; β is the adjustment coefficient; A i is the area of ​​the current dust region; A max is the maximum area of ​​the large particle, A base is the basic amplitude; α is the amplification factor; A max is the maximum area of ​​the large particle; A i is the area of ​​the current dust region.

[0078] A variable frequency dust cleaning device for improving the efficiency of photovoltaic power generation also includes an environmental sensor for monitoring external environmental parameters such as ambient temperature, humidity, wind speed, etc.; the control system dynamically adjusts the working state of the dust cleaning device according to the monitored environmental data, including vibration frequency, amplitude and cleaning cycle, to adapt to different climatic conditions; when the temperature is too high or the humidity is too high, the control system automatically adjusts the cleaning intensity to avoid excessive dust adhesion or damage.

[0079] The cleaning inventions in the prior art include manual cleaning, mechanical vibration, compressed air blowing and other methods. Although these methods can remove dust, they all have the limitation of being unable to be precisely adjusted, especially the poor adaptability to particle size and dust adhesion. The details are as follows:

[0080] Manual cleaning: Although it is cleaned by manual brushing or wiping with a rag with high precision, it is labor-intensive, inefficient, and causes great damage to the surface of the photovoltaic panel.

[0081] Mechanical vibration: Mechanical vibration devices remove dust by applying vibrations to the surface, but their vibration frequency and amplitude are usually fixed and cannot be dynamically adjusted according to different particle sizes and adhesion forces, which may result in unsatisfactory cleaning results, especially for fine particles or difficult-to-clean areas.

[0082] Compressed air blowing: Compressed air is suitable for cleaning light dust, but when there is a lot of dust accumulation, the blowing effect is not obvious, and it cannot handle dust with strong adhesion.

[0083] Electromagnetic vibration cleaning: This method uses electromagnetic vibration to clean tiny particles. Although it has a certain effect on fine particles, the adjustment of its frequency and amplitude is usually fixed and lacks the ability to adjust according to actual needs.

[0084] To ensure the fairness of the comparative experiments, the experiments were conducted under the same environmental conditions. All experiments used the same type of photovoltaic panels and simulated the same amount of dust accumulation in a standardized manner. The experimental time for all cleaning methods was set to 30 minutes, and the surface of the photovoltaic panels was pretreated before cleaning to make the dust accumulation the same. In the experiment, we measured the dust area removed by each cleaning method and quantitatively analyzed the cleaning effect through image processing technology. In addition, all methods were carried out in an indoor environment with a temperature of 25°C and a humidity of about 60% to eliminate the influence of the external environment on the experimental results.

[0085] Depend on Figure 4 As shown, after 30 minutes of cleaning time, the present invention is particularly outstanding in cleaning effect compared with other prior art inventions. The present invention dynamically adjusts the frequency and amplitude of vibration through the control system, and can remove 85% of dust in the same time, which is significantly better than traditional cleaning methods:

[0086] The present invention: removes 85% of the dust, and only 15% of the dust area remains after cleaning.

[0087] Manual cleaning: Only 55% of the dust was removed, and 45% remained in the dusty area after cleaning.

[0088] Mechanical vibration: removes 50% of the dust, leaving 50% of the dust area after cleaning.

[0089] Compressed air: Removes 45% of dust, leaving 55% of dust in the cleaned area.

[0090] Electromagnetic vibration cleaning: removes 40% of dust, 60% of dust remains in the area after cleaning

[0091] In the same time, the present invention can more effectively remove dust from the surface of photovoltaic panels or solar thermal panels, and the cleaning effect is much better than traditional methods. Traditional methods such as manual cleaning, mechanical vibration, compressed air blowing, etc., not only have limited cleaning effects, but also have poor removal capabilities for stubborn dust or tiny particles.

[0092] Depend on Figure 5 As shown, this experiment also compares the cleaning effects of different particle sizes. Large dust particles: The present invention can remove 85% of large dust particles, while the effects of mechanical vibration and compressed air are 70% and 45% respectively. Although mechanical vibration can remove some large particles, the cleaning effect is inferior because it cannot accurately adjust the vibration frequency and amplitude.

[0093] Small dust particles: The cleaning effect of the present invention reaches 90%, mechanical vibration is 65%, and compressed air is 55%. Smaller dust particles require more delicate vibration adjustment, and the control system can automatically adjust the high-frequency micro-vibration to ensure that these fine particles are effectively removed.

[0094] Particle dust: The present invention has a cleaning effect of up to 92% on tiny particles, which is significantly higher than mechanical vibration (60%) and compressed air (58%). Tiny particles usually have strong adhesion and require precise vibration control. The present invention achieves thorough removal of particles through precise adjustment of frequency and amplitude.

[0095] The control system of the present invention can dynamically adjust the vibration frequency and amplitude during the cleaning process according to the size of different particles to ensure efficient cleaning of different types of dust. Compared with traditional methods, the present invention has stronger adaptability to small and large particles and can provide more accurate cleaning under different environmental conditions.

[0096] The present invention is not limited to the above-mentioned embodiments. Anyone should be aware of the structural changes made under the enlightenment of the present invention. All technical inventions that are the same or similar to the present invention fall within the protection scope of the present invention. The technology, shape, and structural parts not described in detail in the present invention are all well-known technologies.

Claims

1. A variable frequency dust cleaning device for improving photovoltaic power generation efficiency, characterized in that: include: A signal generator, used for sending a variable frequency signal; A power amplifier, connected to the signal generator, for amplifying the frequency conversion signal to a required power; Fixed bracket (2); A transducer (1), which is fixedly mounted on a flat or curved surface of a plate (3) via a fixing bracket (2), and is connected to a power amplifier, and is used to convert a power signal into vibration and act on the surface of a photovoltaic or photothermal plate (3); A controller (4) is provided with a control system, wherein the control system is used to adjust the output frequency of the signal generator and control the working state of the transducer (1). The control system can gradually reduce the frequency of the signal generator within a certain period of time to complete a dust cleaning process.

2. A variable frequency dust cleaning device for improving photovoltaic power generation efficiency according to claim 1, characterized in that: The signal generator can generate a variable frequency signal with a frequency of 10kHz to 20kHz; the power amplifier can amplify the frequency signal power output by the signal generator to 50W to 200W; the control system can control the frequency of the signal generator to gradually decrease from 20kHz to 10kHz within 30 seconds.

3. A variable frequency dust cleaning device for improving photovoltaic power generation efficiency according to claim 1, characterized in that: It also includes a visual monitoring device for real-time monitoring of dust distribution on the surface of a photovoltaic or solar thermal panel; the visual monitoring device detects dust in uncleaned areas on the panel surface through an image processing algorithm and transmits a feedback signal to a control system; the control system automatically adjusts the vibration frequency and amplitude according to the feedback signal to ensure that the dust is completely removed, and the steps are: Use visual monitoring equipment to scan the surface of photovoltaic or solar thermal panels in real time to obtain the distribution image of dust on the panel surface. Then, use image processing algorithms to analyze the acquired image, identify the dust accumulation area, and generate dust distribution data. Based on the dust distribution data, evaluate the cleanliness level and determine which areas need further cleaning. Based on the dust distribution detection results, the visual monitoring equipment transmits relevant feedback signals to the control system. The feedback signals include the location and area of ​​the uncleaned dust area and the degree of dust accumulation that needs further cleaning; After receiving the feedback signal, the control system analyzes the areas that are not cleaned enough and automatically adjusts the vibration frequency and amplitude to ensure that the dust in the uncleaned areas can be completely removed.

4. A variable frequency dust cleaning device for improving photovoltaic power generation efficiency according to claim 1, characterized in that: The steps of analyzing the acquired image, identifying the dust accumulation area, and generating dust distribution data through image processing algorithms are as follows: Input image I(x, y), where x and y represent the pixel coordinates in the image. Each pixel of the image can have three components: red, green, and blue (RGB). Then, through the grayscale process, the image is converted into a single-channel image G(x, y). The calculation formula is as follows: G(x, y) = 0.299·R(x, y) + 0.587·G(x, y) + 0.114·B(x, y), where G(x, y) are the red, green, and blue components of the (x, y)th pixel in the image, respectively; Use the threshold segmentation method to separate the dust area in the image from the background. Select an appropriate threshold T and convert the grayscale image into a binary image B(x, y), where the dust area is marked as 1 and the background is 0. For each pixel G(x, y), if its grayscale value is greater than the threshold T, it means that the pixel is a dust area, otherwise it is the background. The binary formula is: By extracting the features of the dust area, the dust accumulation area is determined and the edge of the dust area in the image is detected by the Sobel operator. The expression is: G x (x,y)=B(x+1,y)-B(x-1,y),G y (x, y) = B(x, y+1) - B(x, y-1) is the gradient of the image in the x and y directions, and C(x, y) represents the edge strength of the dust area; The image after edge detection is analyzed by the connected region labeling method to calculate the dust region aggregation degree A. First, let the detected dust region set be D, where each connected region R i satisfy: The aggregation degree A can be expressed by the ratio of the area to the edge density: The calculations of the area and boundary perimeter are: Indicates region R i the boundaries of; The dust distribution map D is generated through the above aggregation and connected area marking results. map (x, y), its value represents the dust density of each pixel, and its expression is: is the indicator function. If (x, y) belongs to the dust region R i , then it is 1, otherwise it is 0, A i For region R i The degree of aggregation.

5. The variable frequency dust cleaning device for improving photovoltaic power generation efficiency according to claim 1, characterized in that: When evaluating the cleanliness of each area, first calculate the total area A of the dusty area. total and the total area of ​​the photovoltaic panels A panel Compare and get the total cleanliness. Then, for each area R i , calculate its cleanliness: in, and The introduction of is to reduce the weight of the thick and strong adhesion areas so that the system can automatically adjust the cleaning strategy; Based on the cleanliness assessment results, the areas that need further cleaning are marked. All areas where the cleanliness is below the preset threshold R i The areas that need to be cleaned will be selected, and the control system will adjust the cleaning strategy based on this information.

6. A variable frequency dust cleaning device for improving photovoltaic power generation efficiency according to claim 1, characterized in that: The control system can adjust the frequency and amplitude of vibration according to the size of dust particles and cleaning requirements. For large dust particles, the system increases the amplitude and vibration intensity. For small dust particles, the system adjusts the frequency to achieve fine cleaning. The steps are as follows: The particle image of the dust area is obtained by the acquired image, and then, according to the area A of the dust area i , set a threshold A threshold To classify particles, the expression is: Classify the particles into large and small particles through threshold classification, and then adjust the frequency and amplitude of the vibration according to the size of the dust particles; According to the adhesion of particles (given by the boundary complexity C i Evaluation), fine-tune the frequency and amplitude of vibration, the expression is: A adjusted =A new ·(1+γ·C i ), f adjusted =f new ·(1-δ·C i ), where γ and δ are adjustment coefficients, which respectively control the increase or decrease of amplitude and frequency in the area with strong adhesion, A adjusted and f adjusted are the adjusted frequency and amplitude, respectively; When all dust areas are cleared, the system calculates the total dust area A total Determine whether to stop cleaning.

7. The variable frequency dust cleaning device for improving photovoltaic power generation efficiency according to claim 1, characterized in that: When adjusting the frequency and amplitude of vibration according to the size of dust particles, the amplitude of vibration is increased for large dust particles, and the expression is: For small dust particles, the frequency of vibration is adjusted as follows: Among them, f base is the fundamental frequency, β is the adjustment coefficient, A i is the area of ​​the current dust region, A max is the maximum area of ​​the large particle, A base is the basic amplitude, α is the amplification factor, A max is the maximum area of ​​the large particle, A i is the area of ​​the current dust region.

8. The variable frequency dust cleaning device for improving photovoltaic power generation efficiency according to claim 1, characterized in that: It also includes environmental sensors for monitoring ambient temperature, humidity and wind speed; the control system dynamically adjusts the working state of the cleaning device according to the monitored environmental data, including vibration frequency, amplitude and cleaning cycle, to adapt to different climatic conditions; when the temperature is too high or the humidity is too high, the control system automatically adjusts the cleaning intensity to avoid excessive dust adhesion or damage.

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