Solar photovoltaic power generation MPPT control method and system based on perturbation and observation method

Abstract

The invention relates to a perturbation and observation method-based solar photovoltaic power generation MPPT (maximum power point tracking) control method and system, and relates to the field of photovoltaic power generation. Determining the number of cycles according to the disturbance time and a preset disturbance cycle; when the cycle number is an integer, acquiring the preset output power of the photovoltaic module; applying disturbance to the preset photovoltaic module according to the preset disturbance step length, and obtaining the disturbance power of the preset photovoltaic module; when the disturbance power is higher than the output power, applying disturbance to a preset photovoltaic module according to a preset disturbance step length; and when the disturbance power is not higher than the output power, reversely applying disturbance to the preset photovoltaic module according to the preset disturbance step length. According to the invention, the reliability of photovoltaic power generation is improved, and the optimal power generation power in the current environment can be achieved.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic power generation, and in particular to a solar photovoltaic power generation MPPT control method and system based on a perturbation-observation method. Background Art

[0002] Solar photovoltaic power generation is a technology that uses photovoltaic modules to directly convert sunlight energy into electrical energy based on the principle of the photovoltaic effect.

[0003] Solar energy, as a clean energy resource, is far cleaner and less polluting than traditional combustion-based energy sources. In a reliable geographical environment, it can provide a high-quality resource for solar photovoltaic power generation. Leveraging local solar resources can reduce dependence on external energy supplies and improve energy independence and security.

[0004] Photovoltaic modules are greatly affected by external factors, which can easily lead to large fluctuations in the power generation of the photovoltaic modules, thereby affecting the power generation efficiency of the entire photovoltaic system. Summary of the Invention

[0005] In order to improve the reliability of photovoltaic power generation and achieve the optimal power generation power under the current environment, the present invention provides a solar photovoltaic power generation MPPT control method and system based on the perturbation and observation method.

[0006] In a first aspect, the present invention provides a solar photovoltaic power generation MPPT control method based on the perturbation and observation method, which adopts the following technical solutions: A solar photovoltaic power generation MPPT control method based on a perturbation-observation method, comprising: Get the disturbance time of the applied disturbance; Determine the number of cycles according to the disturbance time and the preset disturbance cycle; When the number of cycles is an integer, the output power of the preset photovoltaic module is obtained; Applying a disturbance to a preset photovoltaic component according to a preset disturbance step size, and obtaining the disturbance power of the preset photovoltaic component; When the disturbance power is higher than the output power, a disturbance is applied to the preset photovoltaic module according to the preset disturbance step size; When the disturbance power is not higher than the output power, a disturbance is applied to the preset photovoltaic component in the reverse direction according to a preset disturbance step size.

[0007] By adopting the above technical solution, the perturbation observation method is used to adjust the output voltage or current of the photovoltaic module to regulate the output power of the photovoltaic module, so that the output of the solar photovoltaic module quickly approaches the maximum power point in a relatively short period of time, and then achieves the optimal power generation power in the current environment when the light changes rapidly, thereby improving the reliability of photovoltaic power generation.

[0008] Optionally, a disturbance step length adjustment method is further included, and the disturbance step length adjustment method includes: Calculate the quotient of the number of cycles and the preset step period and define it as the adjustment period; When the adjustment period is an integer, the difference between the disturbance power and the output power is calculated and defined as the power difference; When the power difference is higher than a preset rapid change threshold, the difference between the preset disturbance step length and the preset adjustment step length is calculated and defined as the disturbance step length; When the power difference is lower than a preset slow-changing threshold, the sum of the preset disturbance step length and the preset adjustment step length is calculated and defined as the disturbance step length.

[0009] By adopting the above technical solution, the disturbance step size is adjusted according to the actual situation. When the external temperature or light intensity changes greatly, a larger disturbance step size is adopted to enhance the tracking effect. When approaching the maximum power point, a smaller disturbance step size is adopted to make the photovoltaic module work stably near the maximum power point, thereby improving the system's adaptability to light and temperature changes.

[0010] Optionally, a foreign body removal method is also included, and the foreign body removal method includes: Acquire a component image of a preset photovoltaic component; Determine whether there are foreign objects on the photovoltaic modules based on the module images; When there are foreign objects on the photovoltaic module, the foreign object area is determined based on the module image; Determine the knocking position according to the knocking area; Controlling a preset knocking device to reach the knocking position according to the knocking position, and determining the area of ​​the foreign matter according to the foreign matter area; Determine the knocking frequency according to the area of ​​the foreign body; The preset knocking device is controlled to knock the foreign object according to the knocking frequency.

[0011] By adopting the above technical solution, when there is foreign matter on the surface of the photovoltaic module, it is easy to cause the intensity and area of ​​light exposure to the photovoltaic module to decrease, thereby causing the power generation power of the photovoltaic module to decrease. The foreign matter is knocked by the knocking device to break the foreign matter, thereby ensuring the power generation power of the photovoltaic module.

[0012] Optionally, the foreign matter removal method further includes: When there is foreign matter on the photovoltaic module, obtaining a preset module temperature of the photovoltaic module; Determine the knock threshold based on the component temperature and determine the foreign matter density based on the component image; Determine the resonant frequency of the foreign body based on the foreign body density; The knocking frequency is determined based on the foreign body area, resonance frequency and knocking threshold.

[0013] By adopting the above technical solution, the toughness and strength of the surface of the photovoltaic module are affected by temperature. The upper limit of the knocking frequency on the surface of the photovoltaic module is determined according to the temperature, and then the frequency closest to the resonant frequency of the foreign object is selected to knock the foreign object according to the density of the foreign object, so as to quickly remove the foreign object without damaging the photovoltaic module.

[0014] Optionally, the foreign matter removal method further includes: When there are foreign objects on the photovoltaic module, determine whether there is a shadow at the knocking position based on the module image; When there is no shadow at the knocking position, the reverse position is determined according to the knocking position; Controlling a preset knocking device to reach a reverse position according to the reverse position, and determining a reverse frequency according to the knocking frequency and a preset photovoltaic thickness; The preset knocking device is controlled according to the reverse frequency to knock the foreign object.

[0015] By adopting the above technical solution, when there is light at the location of the foreign object, the knocking device is likely to leave a shadow on the photovoltaic module when it moves to the location of the foreign object, thereby reducing the illuminated area of ​​the photovoltaic module. By knocking in the opposite direction on the back of the photovoltaic module to remove the foreign object, the illuminated area of ​​the photovoltaic module can be increased.

[0016] Optionally, a dust treatment method is further included, and the dust treatment method includes: When there are foreign objects on the photovoltaic modules, obtain the ambient wind speed; When the ambient wind speed exceeds the preset dust threshold, determine whether there is dust based on the component image; When dust is present, the dust visibility is determined based on the component image; Determine dust density based on dust visibility; Determine the dust emission frequency based on dust density and ambient wind speed; When the dust frequency is higher than a preset damage threshold, the preset knocking device is controlled to stop knocking foreign objects.

[0017] By adopting the above technical solution, when the surface of the photovoltaic module is subjected to high-frequency knocking of sand and dust, the toughness and strength of the surface of the photovoltaic module are likely to decrease. At this time, knocking foreign objects by the knocking device can easily cause damage to the photovoltaic module. The knocking device is controlled to stop to reduce damage to the photovoltaic module.

[0018] Optionally, the dust treatment method further includes: When the dust frequency is higher than the preset damage threshold, the loss area of ​​foreign matter is determined based on the component image; Determine the loss area of ​​foreign matter based on the loss area and foreign matter area; Determine the frequency of dust impact based on the loss area and foreign matter density; When the knocking frequency is higher than the striking frequency, the ambient wind direction and the component orientation of the photovoltaic module are obtained; Determine the strike coefficient based on the ambient wind direction and component orientation; Determine the adjustment factor based on the strike coefficient, strike frequency, and strike frequency; Determine the adjustment angle based on the adjustment coefficient, ambient wind direction, and component orientation; Control the preset PV panel rotation direction according to the adjustment angle.

[0019] By adopting the above technical solution, when the dust density is high, the photovoltaic modules cannot generate electricity normally. At this time, the orientation of the photovoltaic modules is adjusted to adjust the impact force of the dust on the surface of the photovoltaic modules, so that the dust can hit the foreign objects to remove the foreign objects and improve the working stability of the photovoltaic modules.

[0020] Optionally, the dust treatment method further includes: Determine the material of foreign matter based on component images; Determine the influence coefficient of temperature on foreign body density based on the material of the foreign body; Determine the influence density based on the component temperature, influence coefficient and foreign matter density; The impact frequency of dust is determined based on the loss area and impact density.

[0021] By adopting the above technical solution, when there is foreign matter on the surface of the photovoltaic module, the part of the photovoltaic module where the foreign matter exists is prone to abnormal heating, resulting in a higher temperature of the foreign matter, and then the density of the foreign matter is affected by the high temperature. The density of the foreign matter is predicted based on the temperature of the photovoltaic module, so as to evaluate the degree of impact of dust on the foreign matter, thereby improving the accuracy of photovoltaic control.

[0022] In a second aspect, the present application provides a solar photovoltaic power generation MPPT control system based on the perturbation and observation method, which adopts the following technical solutions: A solar photovoltaic power generation MPPT control system based on a perturbation-observation method, comprising: Photovoltaic panels, which convert solar energy into electricity; Sensor module, used to obtain disturbance time, output power, disturbance power, component image, component temperature and ambient wind speed; A control module, configured to store and execute a program of any of the above-mentioned solar photovoltaic power generation MPPT control methods based on the perturbation-observation method; Charging control module, used to manage the charging process of lithium batteries; Protection circuit module, used to provide overload, short circuit and overheat protection; Communication module, used to realize communication between the system and users.

[0023] By adopting the above technical solution, the perturbation observation method is used to adjust the output voltage or current of the photovoltaic module to regulate the output power of the photovoltaic module, so that the output of the solar photovoltaic module quickly approaches the maximum power point in a relatively short period of time, and then achieves the optimal power generation power in the current environment when the light changes rapidly, thereby improving the reliability of photovoltaic power generation.

[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. The perturbation observation method is used to adjust the output voltage or current of the photovoltaic module to regulate the output power of the photovoltaic module, so that the output of the solar photovoltaic module quickly approaches the maximum power point in a relatively short period of time, thereby achieving the optimal power generation power under the condition of rapid changes in light intensity, thereby improving the reliability of photovoltaic power generation; 2. Adjust the perturbation step size according to the actual situation. When the external temperature or light intensity changes greatly, adopt a larger perturbation step size to enhance the tracking effect. When approaching the maximum power point, adopt a smaller perturbation step size to ensure that the photovoltaic module operates stably near the maximum power point, thereby improving the system's adaptability to light and temperature changes. 3. When there are foreign objects on the surface of the photovoltaic module, it is easy to cause the intensity and area of ​​light exposure to the photovoltaic module to decrease, thereby reducing the power generation capacity of the photovoltaic module. The foreign objects are knocked by the knocking device to break them, thereby ensuring the power generation capacity of the photovoltaic module. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a flow chart of the solar photovoltaic power generation MPPT control method based on the perturbation and observation method; Figure 2 It is a flow chart of the perturbation step size adjustment method; Figure 3 The process of foreign body removal method Figure 1 ; Figure 4 The process of foreign body removal method Figure 2 ; Figure 5 The process of foreign body removal method Figure 3 ; Figure 6 The process of dust treatment method Figure 1 ; Figure 7 The process of dust treatment method Figure 2 ; Figure 8 The process of dust treatment method Figure 3 . DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0027] Reference Figure 1 , a solar photovoltaic power generation MPPT control method based on the perturbation observation method includes: Step 100: Obtain the disturbance time of applying the disturbance.

[0028] Photovoltaic modules refer to devices used to convert solar energy into electrical energy. Photovoltaic modules are selected by staff based on actual conditions. Perturbation refers to a method of adjusting the output power of a photovoltaic module by adjusting the voltage or current output by the photovoltaic module. Perturbation time refers to the length of time that has passed since the first disturbance was applied. The disturbance time can be obtained through a counter. The method for obtaining the disturbance time is selected by staff based on actual conditions and will not be elaborated here.

[0029] Step 101: Determine the number of cycles according to the disturbance time and a preset disturbance cycle.

[0030] The perturbation period is the manually set time interval between perturbations. It is selected by the operator based on actual conditions and is not detailed here. The period number is the current time period within which the perturbation is applied. The period number is typically calculated by dividing the perturbation time by the perturbation period.

[0031] Step 102: When the number of cycles is an integer, obtain the preset output power of the photovoltaic component.

[0032] An integer number of cycles indicates that disturbance needs to be applied again. Output power refers to the power value of the electrical energy output by the photovoltaic module. The output power can be obtained through a power meter. The method of obtaining the output power is selected by the staff according to the actual situation and will not be elaborated here.

[0033] Step 103: applying a disturbance to the preset photovoltaic assembly according to a preset disturbance step size, and obtaining the disturbance power of the preset photovoltaic assembly.

[0034] The perturbation step size refers to the amplitude of the voltage or current output by the PV module. The perturbation step size is selected by the staff based on the actual situation and is not detailed here. The perturbation power refers to the power value of the electrical energy output by the PV module after the perturbation is applied. The perturbation power can be obtained using a power meter. The method for obtaining the perturbation power is selected by the staff based on the actual situation and is not detailed here.

[0035] Step 104: When the disturbance power is higher than the output power, a disturbance is applied to the preset photovoltaic assembly according to a preset disturbance step size.

[0036] The disturbance power being higher than the output power indicates that the power of the electric energy output by the photovoltaic module increases after the disturbance is applied, that is, the maximum power point of the current environment is in the direction of the applied disturbance. At this time, the disturbance is continued to be applied to drive the power of the electric energy output by the photovoltaic module to approach the maximum power point.

[0037] Step 105: When the disturbance power is not higher than the output power, a disturbance is applied in the reverse direction to the preset photovoltaic assembly according to a preset disturbance step size.

[0038] The disturbance power is not higher than the output power, which means that the power of the electric energy output by the photovoltaic module does not increase after the disturbance is applied. That is, the maximum power point of the current environment is in the opposite direction of the applied disturbance. At this time, the disturbance is applied in the reverse direction to drive the power of the electric energy output by the photovoltaic module to approach the maximum power point.

[0039] The perturbation observation method is used to adjust the output voltage or current of the photovoltaic module to regulate the output power of the photovoltaic module, so that the output of the solar photovoltaic module quickly approaches the maximum power point in a shorter period of time, and then achieves the optimal power generation power in the current environment when the light changes rapidly, thereby improving the reliability of photovoltaic power generation.

[0040] Reference Figure 2 , the perturbation step size adjustment methods include: Step 200: Calculate the quotient of the number of cycles and the preset step period, and define it as the adjustment period.

[0041] The step period is the manually set time interval for adjusting the disturbance step. The step period is selected by the staff based on the actual situation and will not be described in detail here. The adjustment period is the time period of the current time in which the disturbance step is adjusted.

[0042] Step 201: When the adjustment period is an integer, the difference between the disturbance power and the output power is calculated and defined as the power difference.

[0043] An integer adjustment period indicates that the disturbance step size needs to be adjusted again. The power difference refers to the change in the power output of the photovoltaic module after the disturbance is applied.

[0044] Step 202: When the power difference is higher than a preset rapid change threshold, a difference between a preset disturbance step length and a preset adjustment step length is calculated and defined as the disturbance step length.

[0045] The adjustment step size refers to the unit amplitude used to adjust the disturbance step size. The adjustment step size is selected by the staff based on actual conditions and is not detailed here. The rapid change threshold is the power change value used to determine whether the power output of the PV module is changing too quickly. The rapid change threshold is selected by the staff based on actual conditions and is not detailed here.

[0046] If the power difference is higher than the rapid change threshold, it means that the power of the electric energy output by the photovoltaic module is changing too quickly, that is, the disturbance step size is too large. At this time, the original disturbance step size is subtracted from the adjustment step size to obtain a new disturbance step size, thereby reducing the disturbance step size and making the photovoltaic module work stably near the maximum power point.

[0047] Step 203: When the power difference is lower than the preset slow change threshold, the sum of the preset disturbance step length and the preset adjustment step length is calculated and defined as the disturbance step length.

[0048] The slow change threshold refers to the power change value used to determine whether the power change speed of the electric energy output by the photovoltaic module is too slow. The slow change threshold is selected by the staff according to the actual situation and will not be described in detail here.

[0049] When the power difference is lower than the rapid change threshold, it means that the power change speed of the electric energy output by the photovoltaic module is too slow, that is, the disturbance step size is too small. At this time, the original disturbance step size is added to the adjustment step size to obtain a new disturbance step size, thereby increasing the disturbance step size and enhancing the tracking effect.

[0050] Adjust the disturbance step size according to the actual situation. When the external temperature or light intensity changes greatly, adopt a larger disturbance step size to enhance the tracking effect. When approaching the maximum power point, adopt a smaller disturbance step size to make the photovoltaic module work stably near the maximum power point, thereby improving the system's adaptability to light and temperature changes.

[0051] Reference Figure 3 , foreign body removal methods include: Step 300: Acquire a component image of a preset photovoltaic component.

[0052] The component image refers to a picture of the side of the photovoltaic component exposed to sunlight. The component image can be obtained through a camera. The method of obtaining the component image is selected by the staff according to the actual situation and will not be elaborated here.

[0053] Step 301: Determine whether there is foreign matter on the photovoltaic module based on the module image.

[0054] Foreign matter refers to objects such as dust and bird droppings that easily adhere to and block photovoltaic modules. Image recognition technology can be used to determine whether there are foreign matter on the photovoltaic modules. The method of determining foreign matter is common knowledge among people in this field and will not be elaborated here.

[0055] Step 302: When there is foreign matter on the photovoltaic module, the foreign matter area is determined based on the module image.

[0056] The presence of foreign matter on a photovoltaic module indicates that the photovoltaic module is obstructed, which may easily lead to a reduction in the power generation capacity of the photovoltaic module. The foreign matter area refers to the range of the foreign matter on the photovoltaic module. The area where the foreign matter exists can be identified from the module image through image recognition technology. The method for determining the foreign matter area is common knowledge among people in this field and will not be elaborated here.

[0057] Step 303: Determine the tapping position according to the tapping area.

[0058] A knocking device refers to a device installed on a photovoltaic module for knocking on the surface of the photovoltaic module to remove foreign matter. A two-dimensional linear guide rail for moving the active knocking device is generally provided on the photovoltaic module. The knocking device is selected by the staff according to actual conditions and will not be elaborated here.

[0059] The knocking position refers to the position where the foreign object is knocked by the knocking device to remove the foreign object. Generally, the point with the largest thickness of the foreign object in the foreign object area is used as the knocking position. The knocking position can be determined by image recognition technology. The method of determining the knocking position is common knowledge among people in this field and will not be elaborated here.

[0060] Step 304: Control a preset knocking device to reach the knocking position according to the knocking position, and determine the area of ​​the foreign matter according to the foreign matter area.

[0061] The foreign object area refers to the area value of the foreign object on the photovoltaic module. When there are multiple foreign objects on the photovoltaic module, the foreign object areas of different foreign objects are identified separately. The foreign object area can be determined by image recognition technology. The method for determining the foreign object area is common knowledge among people in this field and will not be elaborated here.

[0062] Step 305: Determine the knocking frequency according to the area of ​​the foreign object.

[0063] The knocking frequency is the frequency value of knocking foreign objects with the knocking device to remove the foreign objects. The larger the area of ​​the foreign object, the greater the knocking frequency. The knocking frequency can be obtained from the knocking data table. The knocking data table refers to a data table that records different knocking frequencies corresponding to intervals with different foreign object areas.

[0064] Step 306: Control a preset knocking device to knock the foreign object according to the knocking frequency.

[0065] The knocking device knocks the foreign matter, thereby breaking the foreign matter and vibrating the surface of the photovoltaic module, thereby further separating the foreign matter from the surface of the photovoltaic module and improving the efficiency of foreign matter removal.

[0066] Reference Figure 4 , foreign body removal methods also include: Step 307: When there is foreign matter on the photovoltaic module, a preset module temperature of the photovoltaic module is obtained.

[0067] The component temperature refers to the temperature value of the component surface. The component temperature can be obtained through a temperature sensor. The method for obtaining the component temperature is selected by the staff according to the actual situation and will not be described in detail here.

[0068] Step 308: Determine a knock threshold according to the component temperature, and determine a foreign matter density according to the component image.

[0069] The toughness and strength of the surface of photovoltaic modules are easily affected by the external temperature. When the toughness and strength decrease, the surface of the photovoltaic modules is more easily damaged by high-frequency knocking. The knocking threshold refers to the maximum knocking frequency value that the surface of the photovoltaic module can withstand at the current temperature. The knocking threshold can be obtained from the threshold data table. The threshold data table refers to a data table that records different temperature ranges and their corresponding knocking thresholds.

[0070] Foreign matter density refers to the density value of foreign matter. Foreign matter density can be determined by image recognition technology. The method for determining foreign matter density is common knowledge in this field and will not be described in detail here.

[0071] Step 309: Determine the resonance frequency of the foreign matter according to the foreign matter density.

[0072] The resonant frequency refers to the specific frequency value at which a foreign object vibrates at a larger amplitude than at other frequencies at a specific frequency. The resonant frequency can be obtained from the resonance data table, which is a data table that records different density ranges and their corresponding resonant frequencies.

[0073] Step 310: Determine the tapping frequency according to the foreign object area, the resonance frequency, and the tapping threshold.

[0074] The method for determining the tapping frequency includes: Step 3101: Determine a first frequency according to the area of ​​the foreign matter.

[0075] The first frequency is the frequency value obtained from the knocking data table according to the area of ​​the foreign body.

[0076] Step 3102: When the first frequency is less than the resonant frequency, the resonant frequency is used as the second frequency.

[0077] The first frequency being lower than the resonant frequency indicates that the first frequency cannot resonate the foreign matter. In this case, a higher resonant frequency is used as the second frequency to allow the foreign matter to be resonated and vibrated away from the surface of the photovoltaic module.

[0078] Step 3103: When the first frequency is not less than the resonant frequency, alternately adopting the first frequency and the resonant frequency as the second frequency.

[0079] The first frequency being not less than the resonant frequency indicates that the resonant frequency cannot completely remove the foreign matter. In this case, the first frequency and the resonant frequency are alternately used to allow the foreign matter to be vibrated away from the surface of the photovoltaic module while resonating.

[0080] Step 3104: When the second frequency is greater than the tapping threshold, the tapping threshold is used as the tapping frequency.

[0081] The second frequency being greater than the knocking threshold value indicates that knocking the photovoltaic module with the second frequency is likely to cause damage to the photovoltaic module. In this case, the knocking threshold value needs to be used as the knocking frequency to reduce damage to the photovoltaic module.

[0082] Step 3105: When the second frequency is not greater than the tapping threshold, the second frequency is used as the tapping frequency.

[0083] If the second frequency is not greater than the knocking threshold, it means that knocking the photovoltaic module at the second frequency is unlikely to damage the photovoltaic module surface, and the second frequency is directly used to knock the photovoltaic module. When the first frequency is not less than the resonant frequency, the first frequency is used as the frequency value of the second frequency.

[0084] Reference Figure 5 , foreign body removal methods also include: Step 311: When there is a foreign object on the photovoltaic module, determine whether there is a shadow at the knocking position based on the module image.

[0085] Image recognition technology can be used to determine whether there is a shadow at the tapping position. The shadow recognition method is common knowledge among people in this field and will not be described in detail here.

[0086] Step 312: When there is no shadow at the tapping position, determine a reverse position according to the tapping position.

[0087] The absence of a shadow at the striking location indicates that the striking location is exposed to sunlight. This means that when the striking device reaches the striking location, it is susceptible to sunlight, casting a shadow on the photovoltaic module. This reduces the area of ​​the photovoltaic module exposed to sunlight, and in turn reduces the luminous power of the photovoltaic module. The reverse position refers to the location on the side of the photovoltaic module that is not exposed to sunlight that corresponds to the striking location. The method for determining the reverse position is common knowledge in the art and will not be elaborated on here.

[0088] Step 313: Control the preset knocking device to reach the reverse position according to the reverse position, and determine the reverse frequency according to the knocking frequency and the preset photovoltaic thickness.

[0089] Photovoltaic thickness refers to the thickness of the photovoltaic module, i.e., the distance between the reverse position and the striking position. Photovoltaic thickness is determined by personnel based on actual conditions and is not detailed here. Reverse frequency refers to the frequency required to produce vibrations at the striking frequency when striking at the reverse position. The determination of reverse frequency is common knowledge in the art and is not detailed here.

[0090] Step 314: Control the preset knocking device to knock the foreign object according to the reverse frequency.

[0091] When there is light at the location of the foreign object, the knocking device is likely to leave a shadow on the photovoltaic module when it moves to the location of the foreign object, thereby reducing the illuminated area of ​​the photovoltaic module. By knocking in the opposite direction on the back of the photovoltaic module to remove the foreign object, the illuminated area of ​​the photovoltaic module can be increased.

[0092] Reference Figure 6 , dust treatment methods include: Step 400: When there is foreign matter on the photovoltaic module, obtain the ambient wind speed.

[0093] Ambient wind speed refers to the wind speed value of the environment in which the photovoltaic modules are located. The ambient wind speed can be obtained through a wind speed sensor. The method for obtaining the ambient wind speed is selected by the staff based on the actual situation and will not be elaborated here.

[0094] Step 401: When the ambient wind speed is higher than a preset dust threshold, determine whether there is dust according to the component image.

[0095] The dust threshold refers to the minimum wind speed at which dust is likely to be generated. This threshold is selected by personnel based on actual conditions and is not detailed here. A wind speed exceeding the threshold indicates that the wind is likely to pick up dust and generate dust. Image recognition technology is used to determine whether dust is occurring. Dust identification methods are well-known in the field and are not detailed here.

[0096] Step 402: When dust is present, determine dust visibility based on the component image.

[0097] The presence of dust means that the raised dust is easily affected by the wind and hits the surface of the photovoltaic module. Dust visibility refers to the maximum distance at which a person with normal vision can identify the target object from the background. Dust visibility can be obtained through image recognition technology. The method of identifying dust visibility is common knowledge among people in this field and will not be elaborated here.

[0098] Step 403: Determine the dust density according to the dust visibility.

[0099] Dust density refers to the density of sand and dust raised in the air. The dust density can be obtained from the density data table. The density data table refers to a data table that records different dust visibility ranges and their corresponding dust densities.

[0100] Step 404: Determine the dust frequency according to the dust density and the ambient wind speed.

[0101] Dust frequency refers to the frequency value of sand and dust with high dust density hitting photovoltaic modules according to the ambient wind speed. The dust frequency can be obtained by calculating the product of dust density, ambient wind speed and module area. The module area refers to the projected area value of the photovoltaic module in the ambient wind direction, which can be obtained by staff in advance. The ambient wind direction refers to the wind direction of the environment in which the photovoltaic module is located. The ambient wind direction can be obtained through a wind speed sensor. The method of obtaining the ambient wind direction is selected by the staff according to the actual situation and will not be elaborated here.

[0102] Step 405: When the dust frequency is higher than a preset damage threshold, the preset knocking device is controlled to stop knocking the foreign object.

[0103] The damage threshold is the minimum frequency at which dust impacts PV panels, causing them to vibrate. This threshold is selected by personnel based on actual conditions and is not detailed here. If the dust frequency exceeds the damage threshold, the dust impact frequency is high, which can easily cause vibrations in the PV panels, thereby reducing the toughness and strength of the PV panel surface. At this point, the impact device should be stopped to reduce the combined vibrations of the impact device and the dust, which could damage the PV panels.

[0104] Reference Figure 7 , dust treatment methods also include: Step 406: When the dust frequency is higher than a preset damage threshold, determine the loss area of ​​the foreign matter based on the component image.

[0105] The loss area refers to the range where foreign matter exists on the photovoltaic module after dust is raised. The loss area can be determined by image recognition technology. The method for determining the loss area is common knowledge among people in this field and will not be elaborated here.

[0106] Step 407: Determine the loss area of ​​the foreign matter according to the loss area and the foreign matter area.

[0107] The loss area refers to the change in the area of ​​foreign matter after dust emission compared to the area of ​​foreign matter before dust emission. The calculation method of the loss area is common knowledge among people in this field and will not be elaborated here.

[0108] Step 408: Determine the impact frequency of dust according to the loss area and the foreign matter density.

[0109] The striking frequency refers to the average frequency of dust hitting the surface of photovoltaic modules per unit time. The degree of impact of dust on the surface of photovoltaic modules per unit time is determined based on the loss area, and the degree of impact is converted into a frequency value for easy comparison. The method for determining the striking frequency refers to the above-mentioned method for determining the knocking frequency.

[0110] Step 409: When the knocking frequency is higher than the striking frequency, the ambient wind direction and the component orientation of the photovoltaic component are obtained.

[0111] If the tapping frequency is higher than the striking frequency, it means that the dust is not striking the PV panels hard enough to completely remove the foreign matter. Module orientation refers to the angle of the PV panels. The method for determining module orientation is determined by the operator based on actual conditions and is not detailed here.

[0112] Step 410: Determine the strike coefficient based on the ambient wind direction and the component orientation.

[0113] The hitting coefficient refers to the ratio of the effective force exerted on the photovoltaic module by dust when it hits the photovoltaic module in the direction of the ambient wind. When the dust hits the surface of the photovoltaic module vertically, the force of the dust acts completely on the surface of the photovoltaic module. The hitting direction of the dust deviates from the vertical, the lower the ratio of the effective force of the dust on the photovoltaic module. The method for determining the hitting coefficient is common knowledge among people in this field and will not be elaborated here.

[0114] Step 411: Determine an adjustment coefficient according to the striking coefficient, striking frequency, and tapping frequency.

[0115] The adjustment coefficient refers to the coefficient of the effective force of sand and dust on the photovoltaic components required to adjust the striking frequency to the striking frequency. The frequency multiplier can be obtained by calculating the quotient of the striking frequency and the striking frequency, and then the product of the frequency multiplier and the striking coefficient can be calculated to obtain the adjustment coefficient.

[0116] Step 412: Determine the adjustment angle according to the adjustment coefficient, the ambient wind direction, and the component orientation.

[0117] The adjustment angle refers to the angle value that the photovoltaic module needs to rotate to make the striking coefficient reach the adjustment coefficient. The method for determining the adjustment angle is common knowledge in this field and will not be described in detail here.

[0118] Step 413: Control the preset photovoltaic assembly rotation direction according to the adjustment angle.

[0119] When the dust density is high, photovoltaic modules cannot generate electricity normally. At this time, the orientation of the photovoltaic modules should be adjusted to adjust the impact of dust on the surface of the photovoltaic modules, so that foreign objects can be removed by the dust and improve the working stability of the photovoltaic modules.

[0120] Reference Figure 8 , dust treatment methods also include: Step 414: Determine the material of the foreign object based on the component image.

[0121] The material of the foreign body refers to the type of material of the foreign body. The material of the foreign body can be determined by image recognition technology. The method for determining the material of the foreign body is common knowledge in this field and will not be described in detail here.

[0122] Step 415: Determine the influence coefficient of temperature on the density of the foreign matter according to the material of the foreign matter.

[0123] The influence coefficient refers to the degree of influence of temperature on the density of foreign matter. The influence coefficient can be obtained by querying the coefficient data table. The coefficient data table refers to a data table that records different materials and their corresponding influence coefficients.

[0124] Step 416: Determine the impact density based on the component temperature, the impact coefficient, and the foreign matter density.

[0125] The impact density refers to the actual density value of the foreign matter at the component temperature. The method for determining the impact density is common knowledge among those skilled in the art and will not be elaborated here.

[0126] Step 417: Determine the impact frequency of dust according to the loss area and the impact density.

[0127] When there is foreign matter on the surface of a photovoltaic module, the part of the photovoltaic module where the foreign matter is present is prone to abnormal heating, resulting in a higher temperature of the foreign matter, which in turn causes the density of the foreign matter to be affected by the high temperature. The density of the foreign matter can be predicted based on the temperature of the photovoltaic module, thereby evaluating the degree of impact of dust on the foreign matter, thereby improving the accuracy of photovoltaic control.

[0128] Based on the same inventive concept, an embodiment of the present invention provides a solar photovoltaic power generation MPPT control system based on the perturbation and observation method, comprising: Photovoltaic panels, which convert solar energy into electricity; Sensor module, used to obtain disturbance time, output power, disturbance power, component image, component temperature and ambient wind speed; A control module, configured to store and execute a program of any of the above-mentioned solar photovoltaic power generation MPPT control methods based on the perturbation-observation method; Charging control module, used to manage the charging process of lithium batteries; Protection circuit module, used to provide overload, short circuit and overheat protection; Communication module, used to realize communication between the system and users.

[0129] Those skilled in the art will clearly understand that for the sake of convenience and brevity, the division of the above-mentioned functional modules is only used as an example for illustration. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working processes of the above-mentioned systems, devices, and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0130] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiment. All technical solutions based on the concept of the present invention are within the scope of protection of the present invention. It should be noted that for those skilled in the art, various improvements and modifications that do not depart from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A solar photovoltaic power generation MPPT control method based on the perturbation and observation method, characterized in that: include: Get the disturbance time of the applied disturbance; Determine the number of cycles according to the disturbance time and the preset disturbance cycle; When the number of cycles is an integer, the output power of the preset photovoltaic module is obtained; Applying a disturbance to a preset photovoltaic component according to a preset disturbance step size, and obtaining the disturbance power of the preset photovoltaic component; When the disturbance power is higher than the output power, a disturbance is applied to the preset photovoltaic module according to the preset disturbance step size; When the disturbance power is not higher than the output power, a disturbance is applied to the preset photovoltaic component in the reverse direction according to a preset disturbance step size.

2. The solar photovoltaic power generation MPPT control method based on the perturbation and observation method according to claim 1 is characterized in that: Also included is a disturbance step length adjustment method, the disturbance step length adjustment method comprising: Calculate the quotient of the number of cycles and the preset step period and define it as the adjustment period; When the adjustment period is an integer, the difference between the disturbance power and the output power is calculated and defined as the power difference; When the power difference is higher than a preset rapid change threshold, the difference between the preset disturbance step length and the preset adjustment step length is calculated and defined as the disturbance step length; When the power difference is lower than a preset slow-changing threshold, the sum of the preset disturbance step length and the preset adjustment step length is calculated and defined as the disturbance step length.

3. The solar photovoltaic power generation MPPT control method based on the perturbation and observation method according to claim 1 is characterized in that: Also included is a foreign body removal method, the foreign body removal method comprising: Acquire a component image of a preset photovoltaic component; Determine whether there are foreign objects on the photovoltaic modules based on the module images; When there are foreign objects on the photovoltaic module, the foreign object area is determined based on the module image; Determine the knocking position according to the knocking area; Controlling a preset knocking device to reach the knocking position according to the knocking position, and determining the area of ​​the foreign matter according to the foreign matter area; Determine the knocking frequency according to the area of ​​the foreign body; The preset knocking device is controlled to knock the foreign object according to the knocking frequency.

4. The solar photovoltaic power generation MPPT control method based on the perturbation and observation method according to claim 3 is characterized in that: The foreign body removal method further comprises: When there is foreign matter on the photovoltaic module, obtaining a preset module temperature of the photovoltaic module; Determine the knock threshold based on the component temperature and determine the foreign matter density based on the component image; Determine the resonant frequency of the foreign body based on the foreign body density; The knocking frequency is determined based on the foreign body area, resonance frequency and knocking threshold.

5. The solar photovoltaic power generation MPPT control method based on the perturbation and observation method according to claim 4 is characterized in that: The method for determining the tapping frequency includes: determining a first frequency according to the area of ​​the foreign matter; When the first frequency is less than the resonant frequency, the resonant frequency is used as the second frequency; When the first frequency is not less than the resonant frequency, the first frequency and the resonant frequency are alternately used as the second frequency; When the second frequency is greater than the tapping threshold, the tapping threshold is used as the tapping frequency; When the second frequency is not greater than the tapping threshold, the second frequency is adopted as the tapping frequency.

6. The solar photovoltaic power generation MPPT control method based on the perturbation and observation method according to claim 5, characterized in that: The foreign body removal method further comprises: When there are foreign objects on the photovoltaic module, determine whether there is a shadow at the knocking position based on the module image; When there is no shadow at the knocking position, the reverse position is determined according to the knocking position; Controlling a preset knocking device to reach a reverse position according to the reverse position, and determining a reverse frequency according to the knocking frequency and the preset photovoltaic thickness; The preset knocking device is controlled according to the reverse frequency to knock the foreign object.

7. The solar photovoltaic power generation MPPT control method based on the perturbation and observation method according to claim 6, characterized in that: Also included is a dust treatment method, the dust treatment method comprising: When there are foreign objects on the photovoltaic modules, obtain the ambient wind speed; When the ambient wind speed exceeds the preset dust threshold, determine whether there is dust based on the component image; When dust is present, the dust visibility is determined based on the component image; Determine dust density based on dust visibility; Determine the dust emission frequency based on dust density and ambient wind speed; When the dust frequency is higher than a preset damage threshold, the preset knocking device is controlled to stop knocking foreign objects.

8. The solar photovoltaic power generation MPPT control method based on the perturbation and observation method according to claim 7, characterized in that: The dust treatment method further comprises: When the dust frequency is higher than the preset damage threshold, the loss area of ​​foreign matter is determined based on the component image; Determine the loss area of ​​foreign matter based on the loss area and foreign matter area; Determine the frequency of dust impact based on the loss area and foreign matter density; When the knocking frequency is higher than the striking frequency, the ambient wind direction and the component orientation of the photovoltaic module are obtained; Determine the strike coefficient based on the ambient wind direction and component orientation; Determine the adjustment factor based on the strike coefficient, strike frequency, and strike frequency; Determine the adjustment angle based on the adjustment coefficient, ambient wind direction, and component orientation; Control the preset PV panel rotation direction according to the adjustment angle.

9. The solar photovoltaic power generation MPPT control method based on the perturbation and observation method according to claim 8, characterized in that: The dust treatment method further comprises: Determine the material of foreign matter based on component images; Determine the influence coefficient of temperature on foreign body density based on the material of the foreign body; Determine the influence density based on the component temperature, influence coefficient and foreign matter density; The impact frequency of dust is determined based on the loss area and impact density.

10. A solar photovoltaic power generation MPPT control system based on the perturbation and observation method, characterized in that: include: Photovoltaic panels, which convert solar energy into electricity; Sensor module, used to obtain disturbance time, output power, disturbance power, component image, component temperature and ambient wind speed; A control module, configured to store and execute a program of the solar photovoltaic power generation MPPT control method based on the perturbation and observation method according to any one of claims 1 to 8; Charging control module, used to manage the charging process of lithium batteries; Protection circuit module, used to provide overload, short circuit and overheat protection; Communication module, used to realize communication between the system and users.

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