Solar photovoltaic power generation mppt control method and system based on disturbance observation method

Abstract

The present application relates to a solar photovoltaic power generation MPPT control method and system based on disturbance observation method, and relates to the field of photovoltaic power generation, which comprises obtaining a disturbance time of applying disturbance; determining a period number according to the disturbance time and a preset disturbance period; when the period number is an integer, obtaining an output power of a preset photovoltaic module; applying disturbance to the preset photovoltaic module according to a preset disturbance step, and obtaining a disturbance power of the preset photovoltaic module; when the disturbance power is higher than the output power, then applying disturbance to the preset photovoltaic module according to the preset disturbance step; when the disturbance power is not higher than the output power, then reversely applying disturbance to the preset photovoltaic module according to the preset disturbance step. The present application has the effect of improving the reliability of photovoltaic power generation and achieving the optimal power generation under the current environment.

Description

TECHNICAL FIELD

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

[0002] Solar photovoltaic power generation is a technology that converts solar energy into electricity directly by using photovoltaic modules according to the principle of photovoltaic effect.

[0003] In the prior art, solar energy, as a clean resource, has the characteristics of high cleanliness and no pollution to the environment compared with traditional combustion resources. In a reliable geographical environment, solar photovoltaic power generation technology can provide high-quality application resources. Using local solar energy resources can reduce dependence on external energy supply and improve energy self-reliance and security.

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

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

[0006] In a first aspect, the present application provides a solar photovoltaic power generation MPPT control method based on a perturbation and observation method, which adopts the following technical solution:

[0007] A solar photovoltaic power generation MPPT control method based on a perturbation and observation method, comprising:

[0008] Obtaining a perturbation time for applying a perturbation;

[0009] Determining the number of cycles according to the perturbation time and a preset perturbation period;

[0010] When the number of cycles is an integer, obtaining the output power of a preset photovoltaic module;

[0011] Applying a perturbation to the preset photovoltaic module according to a preset perturbation step, and obtaining the perturbation power of the preset photovoltaic module;

[0012] When the perturbation power is higher than the output power, then applying a perturbation to the preset photovoltaic module according to the preset perturbation step;

[0013] When the perturbation power is not higher than the output power, then applying a perturbation to the preset photovoltaic module in the opposite direction according to the preset perturbation step.

[0014] By adopting the above technical solutions, the output voltage or current of the photovoltaic module is adjusted by using the perturbation observation method 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 short time, and then the optimal power generation power under the current environment is reached in the case of rapid change of light, thereby improving the reliability of photovoltaic power generation.

[0015] Optionally, the method further comprises a perturbation step adjustment method, wherein the perturbation step adjustment method comprises:

[0016] calculating the quotient of the number of periods and the preset step period, and defining the quotient as an adjustment period;

[0017] when the adjustment period is an integer, calculating the difference between the perturbation power and the output power, and defining the difference as a power difference;

[0018] when the power difference is higher than a preset rapid change threshold, calculating the difference between the preset perturbation step and the preset adjustment step, and defining the difference as a perturbation step;

[0019] when the power difference is lower than a preset slow change threshold, calculating the sum of the preset perturbation step and the preset adjustment step, and defining the sum as the perturbation step.

[0020] By adopting the above technical solutions, the perturbation step is adjusted according to the actual situation, a larger perturbation step is taken when the external temperature or light intensity changes greatly to enhance the tracking effect, and a smaller perturbation step is taken when the maximum power point is approached to make the photovoltaic module work stably near the maximum power point, thereby improving the adaptability of the system to changes in light and temperature.

[0021] Optionally, the method further comprises a foreign matter removal method, wherein the foreign matter removal method comprises:

[0022] acquiring a component image of a preset photovoltaic module;

[0023] judging whether there is foreign matter on the photovoltaic module according to the component image;

[0024] when there is foreign matter on the photovoltaic module, determining a foreign matter area according to the component image;

[0025] determining a knocking position according to the foreign matter area;

[0026] controlling a preset knocking device to reach the knocking position according to the knocking position, and determining a foreign matter area according to the foreign matter area;

[0027] determining a knocking frequency according to the foreign matter area;

[0028] controlling the preset knocking device to knock the foreign matter according to the knocking frequency.

[0029] By adopting the technical scheme, when foreign matters exist on the surface of the photovoltaic module, the intensity and area of the light irradiation on the photovoltaic module are reduced, thereby reducing the power generation of the photovoltaic module, the foreign matters are knocked to be broken by the knocking device, and the power generation of the photovoltaic module is ensured.

[0030] Optionally, the foreign matter removing method further comprises:

[0031] When the foreign matters exist on the photovoltaic module, the component temperature of the photovoltaic module is acquired;

[0032] The knocking threshold is determined according to the component temperature, and the foreign matter density is determined according to the component image;

[0033] The resonance frequency of the foreign matter is determined according to the foreign matter density;

[0034] The knocking frequency is determined according to the foreign matter area, the resonance frequency and the knocking threshold.

[0035] By adopting the technical scheme, the toughness and strength of the surface of the photovoltaic module are affected by the temperature, the upper limit of the knocking frequency of the surface of the photovoltaic module is determined according to the temperature, the frequency closest to the resonance frequency of the foreign matter is selected according to the density of the foreign matter, and the foreign matter is knocked, so that the foreign matter is quickly removed without damaging the photovoltaic module.

[0036] Optionally, the foreign matter removing method further comprises:

[0037] When the foreign matters exist on the photovoltaic module, whether the shadow exists at the knocking position is determined according to the component image;

[0038] When the shadow does not exist at the knocking position, the reverse position is determined according to the knocking position;

[0039] The preset knocking device is controlled to reach the reverse position according to the reverse position, and the reverse frequency is determined according to the knocking frequency and the preset photovoltaic thickness;

[0040] The preset knocking device is controlled to knock the foreign matter according to the reverse frequency.

[0041] By adopting the technical scheme, when the foreign matter exists at the position of light irradiation, the knocking device is easy to leave the shadow on the photovoltaic module when the knocking device moves to the position of the foreign matter, thereby reducing the area of the photovoltaic module irradiated by the light, and the foreign matter is removed by knocking the photovoltaic module reversely on the back, thereby increasing the area of the photovoltaic module irradiated by the light.

[0042] Optionally, the dust raising treatment method further comprises:

[0043] When the foreign matters exist on the photovoltaic module, the environmental wind speed is acquired;

[0044] When the environmental wind speed is higher than a preset dust threshold value, it is determined whether there is a dust-raising phenomenon according to the component image;

[0045] When the dust-raising phenomenon exists, dust visibility is determined according to the component image;

[0046] Dust density is determined according to the dust visibility;

[0047] Dust frequency is determined according to the dust density and the environmental wind speed;

[0048] When the dust frequency is higher than a preset damage threshold value, the preset knocking device is controlled to stop knocking the foreign matter.

[0049] By adopting the above technical solution, when the surface of the photovoltaic component is subjected to high-frequency knocking of the dust, the toughness and strength of the surface of the photovoltaic component are prone to decrease, at this time, the knocking of the foreign matter by the knocking device is prone to cause damage to the photovoltaic component, and the knocking device is controlled to stop to reduce the damage to the photovoltaic component.

[0050] Optionally, the dust treatment method further comprises:

[0051] When the dust frequency is higher than the preset damage threshold value, a loss area of the foreign matter is determined according to the component image;

[0052] A loss area of the foreign matter is determined according to the loss area and the foreign matter area;

[0053] A knocking frequency of the dust is determined according to the loss area and the foreign matter density;

[0054] When the knocking frequency is higher than the knocking frequency, an environmental wind direction and a component orientation of the photovoltaic component are acquired;

[0055] A knocking coefficient is determined according to the environmental wind direction and the component orientation;

[0056] An adjustment coefficient is determined according to the knocking coefficient, the knocking frequency and the knocking frequency;

[0057] An adjustment angle is determined according to the adjustment coefficient, the environmental wind direction and the component orientation;

[0058] The preset photovoltaic component is controlled to turn according to the adjustment angle.

[0059] By adopting the above technical solution, when the dust density is high, the photovoltaic component cannot generate electricity normally, at this time, the orientation of the photovoltaic component is adjusted to adjust the knocking strength of the dust on the surface of the photovoltaic component, so that the foreign matter is knocked by the dust to remove the foreign matter, and the stability of the photovoltaic component in operation is improved.

[0060] Optionally, the dust treatment method further comprises:

[0061] The material of the foreign matter is determined according to the component image;

[0062] determine the influence coefficient of temperature on the density of the foreign matter according to the material of the foreign matter;

[0063] determine the influence density according to the component temperature, the influence coefficient and the density of the foreign matter;

[0064] determine the hitting frequency of the flying dust according to the loss area and the influence density.

[0065] By adopting the above technical solution, when there is foreign matter on the surface of the photovoltaic component, the part of the photovoltaic component where the foreign matter exists is prone to abnormal heating, resulting in a situation that the temperature of the foreign matter is relatively high, and further resulting in that the density of the foreign matter is affected by high temperature. The density of the foreign matter is predicted according to the temperature of the photovoltaic component, so as to evaluate the degree of the flying dust hitting the foreign matter, and further improve the accuracy of photovoltaic control.

[0066] In a second aspect, the application provides a solar photovoltaic power generation MPPT control system based on the perturbation and observation method, which adopts the following technical solution:

[0067] A solar photovoltaic power generation MPPT control system based on the perturbation and observation method, comprising:

[0068] a photovoltaic component for converting solar energy into electric energy;

[0069] a sensor module for acquiring perturbation time, output power, perturbation power, component image, component temperature and environmental wind speed;

[0070] a control module for storing and executing the program of the above-mentioned solar photovoltaic power generation MPPT control method based on the perturbation and observation method;

[0071] a charging control module for managing the charging process of the lithium battery;

[0072] a protection circuit module for providing overload, short circuit and overheat protection;

[0073] a communication module for realizing the communication between the system and the user.

[0074] By adopting the above technical solution, the output voltage or current of the photovoltaic component is adjusted by the perturbation and observation method to adjust the output power of the photovoltaic component, so that the output of the solar photovoltaic component quickly approaches the maximum power point in a short time, and further reaches the best power generation under the current environment in the case of rapid change of light, thereby improving the reliability of photovoltaic power generation.

[0075] In summary, the application has at least one of the following beneficial technical effects:

[0076] 1. Adopting the perturbation observation method 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 short time, and then reaches the optimal power generation power under the current environment in the case of rapid change of light, thereby improving the reliability of photovoltaic power generation;

[0077] 2. Adjusting the perturbation step according to the actual situation, taking a larger perturbation step when the external temperature or light intensity changes greatly to enhance the tracking effect, and taking a smaller perturbation step when approaching the maximum power point to make the photovoltaic module work stably near the maximum power point, thereby improving the adaptability of the system to light and temperature changes;

[0078] 3. When there are foreign matters on the surface of the photovoltaic module, it is easy to cause the photovoltaic module to be subjected to reduced light intensity and area, thereby causing the power generation power of the photovoltaic module to decrease, and the foreign matters are broken by the knocking device to protect the power generation power of the photovoltaic module. BRIEF DESCRIPTION OF DRAWINGS

[0079] Figure 1 It is a flowchart of the solar photovoltaic power generation MPPT control method based on the perturbation observation method;

[0080] Figure 2 It is a flowchart of the foreign matter removal method Figure One ;

[0081] Figure 3 It is a flowchart of the foreign matter removal method Figure Two ;

[0082] Figure 4 It is a flowchart of the dust removal method Figure One ;

[0083] Figure 5 It is a flowchart of the dust removal method Figure Two ;

[0084] Figure 6 It is a flowchart of the dust removal method Figure Three . DETAILED DESCRIPTION

[0085] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.

[0086] Referring to Figure 1 , the solar photovoltaic power generation MPPT control method based on the perturbation observation method comprises:

[0087] Step 100: obtaining the perturbation time of the applied perturbation.

[0088] The photovoltaic module refers to a device for converting solar energy into electric energy, the photovoltaic module is selected by a worker according to actual conditions, the perturbation refers to a method for adjusting the output power of the photovoltaic module by adjusting the voltage or current output by the photovoltaic module, the perturbation time refers to the length of time elapsed since the first time the perturbation is applied, the perturbation time can be obtained by a counter, and the method for obtaining the perturbation time is selected by the worker according to actual conditions, which is not described herein.

[0089] Step 101: determining the cycle number according to the perturbation time and a preset perturbation period.

[0090] The perturbation period refers to a time interval for applying the perturbation set by a person, and the perturbation period is selected by the worker according to actual conditions, which is not described herein. The cycle number is the time period for applying the perturbation in which the current time is located, and the cycle number is generally obtained by calculating the quotient of the perturbation time and the perturbation period.

[0091] Step 102: obtaining the output power of the preset photovoltaic module when the cycle number is an integer.

[0092] The cycle number being an integer represents that the perturbation needs to be applied again at this time, and the output power refers to the power value of the electric energy output by the photovoltaic module, which can be obtained by a power meter, and the method for obtaining the output power is selected by the worker according to actual conditions, which is not described herein.

[0093] Step 103: applying the perturbation to the preset photovoltaic module according to a preset perturbation step and obtaining the perturbation power of the preset photovoltaic module.

[0094] The perturbation step refers to the amplitude of adjusting the voltage or current output by the photovoltaic module, and the perturbation step is selected by the worker according to actual conditions, which is not described herein. The perturbation power refers to the power value of the electric energy output by the photovoltaic module after the perturbation is applied, which can be obtained by a power meter, and the method for obtaining the perturbation power is selected by the worker according to actual conditions, which is not described herein.

[0095] Step 104: applying the perturbation to the preset photovoltaic module according to the preset perturbation step when the perturbation power is higher than the output power.

[0096] The perturbation power being higher than the output power represents that the power of the electric energy output by the photovoltaic module increases after the perturbation is applied, that is, the maximum power point of the current environment is in the direction of applying the perturbation, and the perturbation is continuously applied at this time to drive the power of the electric energy output by the photovoltaic module to tend to the maximum power point.

[0097] Step 105: applying the perturbation to the preset photovoltaic module in the reverse direction according to the preset perturbation step when the perturbation power is not higher than the output power.

[0098] The power of the disturbed power not higher than the output power represents that the power of the electrical energy output by the photovoltaic module after the disturbance is applied does not increase, that is, the maximum power point of the current environment is in the opposite direction of the applied disturbance, at which the disturbance is applied in the opposite direction to drive the power of the electrical energy output by the photovoltaic module to the maximum power point.

[0099] The output voltage or current of the photovoltaic module is adjusted by using the disturbance observation method to adjust the output power of the photovoltaic module, so that the output of the solar photovoltaic module quickly approaches the maximum power point in a short time, and the optimal power generation power under the current environment is reached in the case of rapid change of illumination, thereby improving the reliability of photovoltaic power generation.

[0100] The disturbance step adjustment method comprises:

[0101] Step 200: Calculate the quotient of the number of periods and the preset step period, and define it as the adjustment period.

[0102] The step period refers to the time interval for adjusting the disturbance step, which is selected by the staff according to the actual situation, and is not described here. The adjustment period is the time period for adjusting the disturbance step at the current time.

[0103] Step 201: When the adjustment period is an integer, calculate the difference between the disturbed power and the output power, and define it as the power difference.

[0104] The adjustment period being an integer represents that the disturbance step needs to be adjusted again at this time, and the power difference refers to the change value of the power of the electrical energy output by the photovoltaic module after the disturbance is applied.

[0105] Step 202: When the power difference is higher than the preset rapid change threshold, calculate the difference between the preset disturbance step and the preset adjustment step, and define it as the disturbance step.

[0106] The adjustment step refers to the unit amplitude value for adjusting the disturbance step, which is selected by the staff according to the actual situation, and is not described here. The rapid change threshold refers to the power change value for judging whether the power change speed of the electrical energy output by the photovoltaic module is too fast, which is selected by the staff according to the actual situation, and is not described here.

[0107] The power difference being higher than the rapid change threshold represents that the power change speed of the electrical energy output by the photovoltaic module is too fast at this time, that is, the disturbance step is too large, at which the original disturbance step is reduced by the adjustment step to obtain a new disturbance step, thereby reducing the disturbance step, and thereby making the photovoltaic module work stably near the maximum power point.

[0108] Step 203: When the power difference is lower than the preset slow change threshold, calculate the sum of the preset disturbance step and the preset adjustment step, and define it as the disturbance step.

[0109] The slow change threshold refers to a power change value used to determine whether the power change speed of the power 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 here.

[0110] The power difference lower than the fast change threshold represents that the power change speed of the power output by the photovoltaic module is too slow at this time, that is, the perturbation step is too small. At this time, the original perturbation step is added to the adjustment step to obtain a new perturbation step, so as to increase the perturbation step and further enhance the tracking effect.

[0111] The perturbation step is adjusted according to the actual situation. When the external temperature or light intensity changes greatly, a larger perturbation step is taken to enhance the tracking effect. When close to the maximum power point, a smaller perturbation step is used to make the photovoltaic module work stably near the maximum power point, so as to improve the adaptability of the system to light and temperature changes.

[0112] The foreign matter removal method comprises:

[0113] Step 300: Obtain a preset component image of a photovoltaic module.

[0114] The component image refers to a picture of a side of the photovoltaic module irradiated by sunlight. The component image can be obtained by a camera. The method for obtaining the component image is selected by the staff according to the actual situation, and will not be described here.

[0115] Step 301: Determine whether there is foreign matter on the photovoltaic module according to the component image.

[0116] The foreign matter refers to dust, bird droppings and other objects that are easy to adhere to and block the photovoltaic module. Whether there is foreign matter on the photovoltaic module can be determined by image recognition technology. The method for determining the foreign matter is known to those skilled in the art, and will not be described here.

[0117] Step 302: When there is foreign matter on the photovoltaic module, determine the foreign matter area according to the component image.

[0118] The presence of foreign matter on the photovoltaic module represents that the photovoltaic module is blocked, which is easy to cause the power generation of the photovoltaic module to decrease. 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 component image by image recognition technology. The method for determining the foreign matter area is known to those skilled in the art, and will not be described here.

[0119] Step 303: Determine the knocking position according to the foreign matter area.

[0120] The knocking device refers to a device arranged on the photovoltaic module for knocking the surface of the photovoltaic module to remove the foreign matter. The photovoltaic module is generally provided with a two-dimensional linear guide rail for moving the knocking device. The knocking device is selected by the staff according to the actual situation, and will not be described here.

[0121] The knocking position refers to a position at which the foreign matter is knocked by the knocking device to remove the foreign matter. Generally, a point at which the thickness of the foreign matter in the foreign matter area is the largest is taken as the knocking position. The knocking position can be determined by image recognition technology. The method for determining the knocking position is well known to those skilled in the art, and will not be described here.

[0122] Step 304: The knocking device is controlled to reach the knocking position according to the knocking position, and the foreign matter area is determined according to the foreign matter area.

[0123] The foreign matter area refers to the area value of the foreign matter on the photovoltaic module. When there are multiple foreign matters on the photovoltaic module, the foreign matter areas of different foreign matters are identified respectively. The foreign matter area can be determined by image recognition technology. The method for determining the foreign matter area is well known to those skilled in the art, and will not be described here.

[0124] Step 305: The knocking frequency is determined according to the foreign matter area.

[0125] The knocking frequency refers to the frequency value at which the foreign matter is knocked by the knocking device to remove the foreign matter. The larger the area of the foreign matter is, the larger the knocking frequency is. The knocking frequency can be obtained by querying a knocking data table. The knocking data table refers to a data table in which different knocking frequencies corresponding to different intervals of foreign matter areas are recorded.

[0126] Step 306: The knocking device is controlled to knock the foreign matter according to the knocking frequency.

[0127] The foreign matter is knocked by the knocking device, so that the surface of the photovoltaic module is vibrated while the foreign matter is broken, so that the foreign matter is further separated from the surface of the photovoltaic module, and the efficiency of removing the foreign matter is improved.

[0128] Reference Figure 2 The foreign matter removal method further comprises:

[0129] Step 307: When there is foreign matter on the photovoltaic module, the component temperature of the preset photovoltaic module is obtained.

[0130] The component temperature refers to the temperature value of the component surface. The component temperature can be obtained by a temperature sensor. The method for obtaining the component temperature is selected by the worker according to the actual situation, and will not be described here.

[0131] Step 308: The knocking threshold is determined according to the component temperature, and the foreign matter density is determined according to the component image.

[0132] The toughness and strength of the surface of the photovoltaic module are susceptible to the influence of external temperature, and when the toughness and strength decrease, the surface of the photovoltaic module is more susceptible to damage by high-frequency knocking, the knocking threshold value is the maximum knocking frequency value that the surface of the photovoltaic module can withstand at the current temperature, and the knocking threshold value can be obtained from a threshold value data table, which is a data table recording different temperature intervals and corresponding knocking threshold values.

[0133] The foreign matter density is the density value of the foreign matter, and the foreign matter density can be determined by image recognition technology. The determination method of the foreign matter density is known to those skilled in the art, and will not be described here.

[0134] Step 309: determining the resonance frequency of the foreign matter according to the foreign matter density.

[0135] The resonance frequency is a specific frequency value at which the foreign matter vibrates with a larger amplitude than at other frequencies, and the resonance frequency can be obtained from a resonance data table, which is a data table recording different density intervals and corresponding resonance frequencies.

[0136] Step 310: determining the knocking frequency according to the foreign matter area, the resonance frequency, and the knocking threshold value.

[0137] The determination method of the knocking frequency includes:

[0138] Step 3101: determining a first frequency according to the foreign matter area.

[0139] The first frequency is a frequency value obtained from a knocking data table according to the foreign matter area.

[0140] Step 3102: when the first frequency is less than the resonance frequency, using the resonance frequency as a second frequency.

[0141] The first frequency being less than the resonance frequency means that the first frequency cannot cause the foreign matter to resonate, and at this time, a higher resonance frequency is used as the second frequency to make the foreign matter vibrate off the surface of the photovoltaic module while resonating.

[0142] Step 3103: when the first frequency is not less than the resonance frequency, using the first frequency and the resonance frequency alternately as the second frequency.

[0143] The first frequency not being less than the resonance frequency means that using the resonance frequency cannot completely remove the foreign matter, and at this time, the first frequency and the resonance frequency are used alternately to make the foreign matter vibrate off the surface of the photovoltaic module while resonating.

[0144] Step 3104: when the second frequency is greater than the knocking threshold value, using the knocking threshold value as the knocking frequency.

[0145] The second frequency greater than the knocking threshold value represents that the photovoltaic module is easily damaged by knocking the photovoltaic module with the second frequency, and thus the knocking threshold value is used as the knocking frequency to reduce the damage of the photovoltaic module.

[0146] Step 3105: When the second frequency is not greater than the knocking threshold value, the second frequency is used as the knocking frequency.

[0147] The second frequency not greater than the knocking threshold value represents that the surface of the photovoltaic module is not easily damaged by knocking the photovoltaic module with the second frequency, and thus the second frequency is directly used to knock the photovoltaic module. When the first frequency is not less than the resonance frequency, the first frequency is used as the frequency value of the second frequency.

[0148] Referring to Figure 3 , the foreign matter removing method further comprises:

[0149] Step 311: When the foreign matter exists on the photovoltaic module, whether a shadow exists at the knocking position is determined according to the component image.

[0150] Whether the shadow exists at the knocking position can be determined by image recognition technology, and the method for identifying the shadow is well known to those skilled in the art and is not described here.

[0151] Step 312: When the shadow does not exist at the knocking position, the reverse position is determined according to the knocking position.

[0152] The knocking position without the shadow represents that the knocking position is irradiated by sunlight, that is, the knocking device is easily irradiated by sunlight when reaching the knocking position on the photovoltaic module, thereby reducing the irradiated area of the photovoltaic module and further reducing the light power of the photovoltaic module. The reverse position refers to a position corresponding to the knocking position on the side of the photovoltaic module not irradiated by sunlight, and the method for determining the reverse position is well known to those skilled in the art and is not described here.

[0153] Step 313: The preset knocking device is controlled to reach the reverse position according to the reverse position, and the reverse frequency is determined according to the knocking frequency and the preset photovoltaic thickness.

[0154] The photovoltaic thickness refers to the thickness value of the photovoltaic module, that is, the distance between the reverse position and the knocking position, and the photovoltaic thickness is selected by the staff according to the actual situation and is not described here. The reverse frequency refers to the frequency value required for knocking at the reverse position to generate the knocking frequency vibration at the knocking position, and the method for determining the reverse frequency is well known to those skilled in the art and is not described here.

[0155] Step 314: The preset knocking device knocks the foreign matter according to the reverse frequency.

[0156] When the foreign matter is located in a position with light, the knocking device is easy to leave a shadow on the photovoltaic module when moving to the position of the foreign matter, thereby reducing the light receiving area of the photovoltaic module, and the foreign matter is removed by reverse knocking on the back of the photovoltaic module, thereby increasing the light receiving area of the photovoltaic module.

[0157] With reference to Figure 4 , the dust raising treatment method comprises:

[0158] Step 400: When there is foreign matter on the photovoltaic module, the environmental wind speed is obtained.

[0159] The environmental wind speed refers to the wind speed value of the environment where the photovoltaic module is located, and the environmental wind speed can be obtained by a wind speed sensor. The method for obtaining the environmental wind speed is selected by the staff according to the actual situation, and is not described here.

[0160] Step 401: When the environmental wind speed is higher than the preset dust threshold, it is determined whether there is a dust raising phenomenon according to the component image.

[0161] The dust threshold refers to the minimum value of the wind speed that is easy to raise dust. The dust threshold is selected by the staff according to the actual situation, and is not described here. The environmental wind speed higher than the dust threshold represents that the wind at this time may raise dust to produce the phenomenon of raising dust. Whether the dust raising phenomenon occurs is determined by image recognition technology. The method for identifying dust is known to those skilled in the art, and is not described here.

[0162] Step 402: When there is a dust raising phenomenon, the dust visibility is determined according to the component image.

[0163] The presence of the dust raising phenomenon represents that the raised dust is easy to be affected by the wind and hit the surface of the photovoltaic module. The dust visibility refers to the maximum distance at which a person with normal vision can identify a target object from the background. The dust visibility can be obtained by image recognition technology. The method for identifying the dust visibility is known to those skilled in the art, and is not described here.

[0164] Step 403: The dust density is determined according to the dust visibility.

[0165] The dust density refers to the density of the raised dust in the air. The dust density can be obtained from a density data table. The density data table refers to a data table recording different dust visibility intervals and their corresponding dust densities.

[0166] Step 404: The dust frequency is determined according to the dust density and the environmental wind speed.

[0167] The dust frequency refers to a frequency value of dust density hitting the photovoltaic module according to the environmental wind speed. The dust frequency can be obtained by multiplying the dust density, the environmental wind speed, and the component area. The component area refers to a projection area value of the photovoltaic module in the environmental wind direction. The component area can be obtained by the staff through prior calculation. The environmental wind direction refers to the wind direction of the environment where the photovoltaic module is located. The environmental wind direction can be obtained by the wind speed sensor. The method for obtaining the environmental wind direction is selected by the staff according to the actual situation, which is not described herein.

[0168] Step 405: When the dust frequency is higher than the preset damage threshold, control the preset knocking device to stop knocking the foreign matter.

[0169] The damage threshold refers to the minimum frequency value of the dust hitting the photovoltaic module, which is easy to cause the photovoltaic module to vibrate. The damage threshold is selected by the staff according to the actual situation, which is not described herein. When the dust frequency is higher than the damage threshold, it means that the dust hitting frequency is large at this time, which is easy to cause the photovoltaic module to vibrate, thereby causing the toughness and strength of the surface of the photovoltaic module to decrease. At this time, the knocking device is stopped to reduce the vibration caused by the knocking device and the vibration caused by the dust, so as to avoid the situation that the vibration is superimposed to cause the photovoltaic module to be damaged.

[0170] Referring to Figure 5 , the dust processing method further comprises:

[0171] Step 406: When the dust frequency is higher than the preset damage threshold, determine the loss area of the foreign matter according to the component image.

[0172] The loss area refers to the range of the foreign matter on the photovoltaic module after the dust. The loss area can be determined by image recognition technology. The determination method of the loss area is known to those skilled in the art, which is not described herein.

[0173] Step 407: Determine the loss area of the foreign matter according to the loss area and the foreign matter area.

[0174] The loss area refers to the change value of the area of the foreign matter after the dust compared with the area of the foreign matter before the dust. The calculation method of the loss area is known to those skilled in the art, which is not described herein.

[0175] Step 408: Determine the hitting frequency of the dust according to the loss area and the foreign matter density.

[0176] The hitting frequency refers to the average hitting frequency of the dust on the surface of the photovoltaic module per unit time. According to the loss area, the hitting degree of the dust on the surface of the photovoltaic module per unit time is determined, and the hitting degree is converted into a frequency value for easy comparison. The determination method of the hitting frequency refers to the determination method of the knocking frequency.

[0177] Step 409: When the knocking frequency is higher than the hitting frequency, obtain the environmental wind direction and the component orientation of the photovoltaic module.

[0178] The knocking frequency is higher than the hitting frequency, which represents that the hitting degree of the dust on the photovoltaic module is not enough to completely remove the foreign matter. The component orientation refers to the orientation angle value of the photovoltaic module, and the obtaining method of the component orientation is selected by the staff according to the actual situation, which is not described herein.

[0179] Step 410: determining a hitting coefficient according to the environmental wind direction and the component orientation.

[0180] The hitting coefficient refers to the proportion coefficient of the effective force of the dust on the photovoltaic module when the dust hits the photovoltaic module according to the environmental wind direction and the component orientation. When the dust hits the photovoltaic module vertically, the force of the dust acts completely on the surface of the photovoltaic module. The lower the hitting direction of the dust deviates from the vertical, the lower the proportion coefficient of the effective force of the dust on the photovoltaic module. The determination method of the hitting coefficient is known to those skilled in the art, which is not described herein.

[0181] Step 411: determining an adjustment coefficient according to the hitting coefficient, the hitting frequency and the knocking frequency.

[0182] The adjustment coefficient refers to the proportion coefficient of the effective force of the dust on the photovoltaic module required for adjusting the hitting frequency to the knocking frequency. The frequency ratio can be obtained by calculating the quotient of the knocking frequency and the hitting frequency, and the adjustment coefficient can be obtained by calculating the product of the frequency ratio and the hitting coefficient.

[0183] Step 412: determining an adjustment angle according to the adjustment coefficient, the environmental wind direction and the component orientation.

[0184] The adjustment angle refers to the angle value required for the photovoltaic module to rotate to make the hitting coefficient reach the adjustment coefficient. The determination method of the adjustment angle is known to those skilled in the art, which is not described herein.

[0185] Step 413: controlling the preset photovoltaic module turning direction according to the adjustment angle.

[0186] When the dust density is high, the photovoltaic module cannot generate electricity normally. At this time, the orientation of the photovoltaic module is adjusted to adjust the hitting degree of the dust on the surface of the photovoltaic module, so as to remove the foreign matter by the dust hitting the foreign matter and improve the stability of the photovoltaic module.

[0187] Reference Figure 6 The dust treatment method further comprises:

[0188] Step 414: determining the material of the foreign matter according to the component image.

[0189] The material of the foreign matter refers to the material type of the foreign matter. The material of the foreign matter can be determined by image recognition technology. The determination method of the material of the foreign matter is known to those skilled in the art, which is not described herein.

[0190] Step 415: determining the influence coefficient of temperature on the density of the foreign matter according to the material of the foreign matter.

[0191] The influence coefficient refers to the influence degree value of temperature on the density of the foreign matter, and the influence coefficient can be obtained by querying a coefficient data table, which is a data table recording different materials and their corresponding influence coefficients.

[0192] Step 416: determining the influence density according to the component temperature, the influence coefficient and the density of the foreign matter.

[0193] The influence density refers to the actual density value of the foreign matter at the component temperature, and the determination method of the influence density is well known to those skilled in the art, which is not described here.

[0194] Step 417: determining the hitting frequency of the dust on the foreign matter according to the loss area and the influence density.

[0195] When the photovoltaic component surface exists foreign matter, the part of the photovoltaic component where the foreign matter exists is easy to abnormally heat, resulting in the condition that the temperature of the foreign matter is high, and further resulting in that the density of the foreign matter is affected by high temperature. According to the temperature of the photovoltaic component, the density of the foreign matter is predicted, so as to evaluate the hitting degree of the dust on the foreign matter, and further improve the accuracy of photovoltaic control.

[0196] Based on the same inventive concept, the embodiment of the present application provides a solar photovoltaic power generation MPPT control system based on the perturbation and observation method, comprising:

[0197] The photovoltaic component is used for converting solar energy into electric energy.

[0198] The sensor module is used for acquiring the perturbation time, the output power, the perturbation power, the component image, the component temperature and the environmental wind speed.

[0199] The control module is used for storing and executing the program of the above-mentioned solar photovoltaic power generation MPPT control method based on the perturbation and observation method.

[0200] The charging control module is used for managing the charging process of the lithium battery.

[0201] The protection circuit module is used for providing overload, short circuit and overheat protection.

[0202] The communication module is used for realizing the communication between the system and the user.

[0203] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the division of the above functional modules is exemplified, and in actual application, the above functions can be completed by different functional modules according to needs, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. The specific working process of the system, device and unit described above can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0204] The above is only the preferred embodiment of the present application, and the protection scope of the present application is not limited to the above-mentioned embodiments. Any technical solution falling within the concept of the present application shall fall within the protection scope of the present application. It should be noted that, for ordinary skilled persons in the art, some improvements and refinements without departing from the principles of the present application shall also be considered as the protection scope of the present application.

Claims

1. A perturbation-observation-based MPPT control method for solar photovoltaic power generation, characterized in that, include: Obtain the duration of the applied disturbance; The number of cycles is determined based on the disturbance time and the preset disturbance period; When the number of cycles is an integer, obtain the preset output power of the photovoltaic module; A perturbation is applied to a preset photovoltaic module according to a preset perturbation step size, and the perturbation power of the preset photovoltaic module is obtained. 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, the preset photovoltaic module is subjected to a reverse disturbance according to the preset disturbance step size; It also includes a foreign object removal method, which includes: Obtain a preset image of the photovoltaic module; Determine whether there are foreign objects on the photovoltaic module based on the module image; When there are foreign objects on the photovoltaic module, the foreign object area is determined based on the module image; Determine the striking location based on the area containing the foreign object; The preset striking device is controlled to reach the striking position according to the striking position, and the area of ​​the foreign object is determined according to the foreign object area. Determine the tapping frequency based on the area of ​​the foreign object; The preset striking device strikes the foreign object according to the striking frequency; The foreign matter removal method further includes: When there are foreign objects on the photovoltaic module, the preset module temperature of the photovoltaic module is obtained; The knocking threshold is determined based on the component temperature, and the foreign object density is determined based on the component image. Determine the resonant frequency of the foreign object based on its density; The striking frequency is determined based on the area of ​​the foreign object, the resonant frequency, and the striking threshold.

2. The MPPT control method for solar photovoltaic power generation based on the perturbation-observation method according to claim 1, characterized in that, The method for determining the tapping frequency includes: The first frequency is determined based on the area of ​​the foreign object; 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 used alternately 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 used as the tapping frequency.

3. The MPPT control method for solar photovoltaic power generation based on the perturbation-observation method according to claim 2, characterized in that, The foreign matter removal method further includes: When there are foreign objects on the photovoltaic module, determine whether there is a shadow at the tapping location based on the module image; When there is no shadow at the tapping location, determine the reverse location based on the tapping location; The preset striking device is controlled to reach the reverse position according to the reverse position, and the reverse frequency is determined according to the striking frequency and the preset photovoltaic thickness. The foreign object is struck by a pre-set striking device controlled by the reverse frequency.

4. The MPPT control method for solar photovoltaic power generation based on the perturbation-observation method according to claim 3, characterized in that, It also includes a dust control method, which includes: When there are foreign objects on the photovoltaic module, the ambient wind speed is obtained; When the ambient wind speed is higher than the preset dust threshold, the presence of dust is determined based on the component image. When dust is present, dust visibility is determined based on component images; Dust density is determined based on dust visibility; The dust frequency is determined based on dust density and ambient wind speed. When the dust emission frequency exceeds the preset damage threshold, the preset striking device is controlled to stop striking the foreign object.

5. The MPPT control method for solar photovoltaic power generation based on the perturbation-observation method according to claim 4, characterized in that, The dust control method further includes: When the dust emission frequency exceeds the preset damage threshold, the area of ​​foreign object loss is determined based on the component image; Determine the area of ​​foreign object loss based on the loss area and the foreign object area; The impact frequency of dust is determined based on the area of ​​loss and the density of foreign objects. When the tapping frequency is higher than the striking frequency, the ambient wind direction and the orientation of the photovoltaic module are obtained; The impact factor is determined based on the ambient wind direction and the orientation of the components. The adjustment coefficient is determined based on the striking coefficient, striking frequency, and tapping frequency. The adjustment angle is determined based on the adjustment coefficient, ambient wind direction, and component orientation. The photovoltaic module's rotation is controlled by adjusting the angle.

6. The MPPT control method for solar photovoltaic power generation based on the perturbation-observation method according to claim 5, characterized in that, The dust control method further includes: Determine the material of the foreign object based on the component image; Determine the influence coefficient of temperature on the density of the foreign object based on its material; The influence density is determined based on component temperature, influence coefficient, and foreign matter density. The frequency of dust impact is determined based on the area of ​​loss and the density of impact.

7. A solar photovoltaic power generation MPPT control system based on the perturbation-observation method, characterized in that, include: Photovoltaic modules are used to convert solar energy into electrical energy; The sensor module is used to acquire disturbance time, output power, disturbance power, component image, component temperature and ambient wind speed; A control module for storing and executing the program of the solar photovoltaic power generation MPPT control method based on the perturbation-observation method as described in any one of claims 1 to 6; The charging control module is used to manage the charging process of the lithium battery; Protection circuit module, used to provide overload, short circuit and overheat protection; The communication module is used to enable communication between the system and the user.

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