Method for determining conversion temperature of photovoltaic module

Abstract

The invention discloses a method for determining the conversion temperature of a photovoltaic module. The method comprises the following steps: S1, acquiring operation data of a target photovoltaic module; s2, extracting required electrical parameters according to the operation data; and S3, inputting the operation data and the extracted required electrical parameters into a conversion temperature model to obtain the conversion temperature of the target photovoltaic module. The problem that the conversion temperature of the target photovoltaic module cannot be determined when a tester performs IEC 60891 conversion on the current-voltage (I-V) characteristic curve of the target photovoltaic module outdoors can be effectively solved, accurate and convenient conversion of the I-V characteristic curve of the photovoltaic module is realized, the key technical problem in the IEC 60891 program of the photovoltaic module is solved, and the test efficiency is improved. And an effective technical support is provided for a tester to carry out converted work.

Description

Technical Field

[0001] The invention belongs to the field of photovoltaic technology, and in particular, relates to a method for determining a conversion temperature of a photovoltaic module. Background Art

[0002] Obtaining the current-voltage (IV) characteristic curve of photovoltaic modules under standard test conditions or selected conditions is a very important task in the field of photovoltaic power generation technology. When conducting performance tests on photovoltaic modules outdoors, testers are usually unable to measure their IV characteristic curves under standard test conditions or selected conditions. Therefore, it is necessary to convert the IV characteristic curves of photovoltaic modules measured on site to standard test conditions or selected conditions using the IEC 60891 procedure. The above standard test conditions (STC, Standard test conditions) refer to irradiance of 1000W / m 2 , battery temperature 25℃, air quality AM1.5G.

[0003] The application of IEC 60891 regulations requires obtaining the irradiance and corresponding operating temperature received by the target photovoltaic module before conversion. Outdoors, solar irradiance can be easily determined using a radiometer, but it is difficult to accurately determine its operating temperature. This is because the solar cells are encapsulated in glass and the temperature sensor cannot be installed on the cell. In addition, there are more than 60 cells encapsulated in a photovoltaic module, and the operating temperatures of each cell are different, so it is impossible to determine which cell's operating temperature should be selected as the conversion temperature. The IEC 60891 regulations recommend that the tester use four temperature sensors to measure the backplane temperature of the four cells in the target photovoltaic module and obtain the average value as its operating temperature. This method is based on two assumptions: 1. The deviation between the backplane temperature of the photovoltaic module and the junction temperature of the cell is very small and can be ignored; 2. The temperature distribution of the photovoltaic module is uniform, that is, the temperature of all cells in the photovoltaic module is consistent.

[0004] However, the above two assumptions based on this method do not hold true under outdoor conditions. First, the photovoltaic module is a multi-layer structure, and the solar cell is encapsulated by film and glass. The tester can only measure the backplane temperature corresponding to the cell, not the cell junction temperature required by the IEC 60891 specification. The temperature difference between the two is 1-3℃, and the specific value varies depending on factors such as the photovoltaic module structure, installation conditions, and weather conditions. Using the backplane temperature instead of the cell junction temperature will cause inaccurate conversion, and simply adding 1-3℃ to the backplane temperature cannot achieve the required accuracy. Second, photovoltaic modules are usually composed of multiple single solar cells in series and parallel. The temperature of these cells varies greatly outdoors. The reasons for this phenomenon are: the electrical performance of the cells encapsulated in the module is different; the heat dissipation capacity of the edge and center of the photovoltaic module is inconsistent; the different installation heights, angles, and ground types of photovoltaic modules cause uneven irradiation and uneven heat dissipation. Therefore, testers often do not know which four cells' backplane temperatures should be measured.

[0005] In addition, IEC 60904-5 proposes a solution to the equivalent battery temperature. The equivalent temperature uses the dependence of the open circuit voltage of the photovoltaic module on the temperature. By measuring the open circuit voltage of the target photovoltaic module, the conversion temperature of the photovoltaic module is calculated. However, this method is not universal, because the dependence of the open circuit voltage on the temperature of photovoltaic modules of different models and the same model with different degradation conditions is different. In addition, the acquisition of this dependence requires tedious and complicated indoor experiments, which is extremely inconvenient for testers to perform conversion work outdoors. Summary of the invention

[0006] In order to solve the technical problems existing in the above-mentioned prior art, the present invention provides a method for determining the conversion temperature of a photovoltaic module, which does not require tedious and complicated indoor experiments and can greatly improve the accuracy of IEC 60891 conversion of the IV characteristic curve of the photovoltaic module under outdoor conditions.

[0007] According to one aspect of the present invention, a method for determining the conversion temperature of a photovoltaic component provided includes: step S1: acquiring operating data of a target photovoltaic component; step S2: extracting required electrical parameters based on the operating data; step S3: inputting the operating data and the extracted required electrical parameters into a conversion temperature model to obtain the conversion temperature of the target photovoltaic component.

[0008] In an example of the conversion temperature determination method provided in the above aspect, the step S1 includes: step S11: obtaining the current-voltage characteristic curve data of the target photovoltaic component; step S12: obtaining the accurate backplane temperature data of all batteries of the target photovoltaic component; step S13: obtaining the environmental parameter data where the target photovoltaic component is installed.

[0009] In an example of the conversion temperature determination method provided in the above aspect, the step S12 includes: step S121: using a temperature sensor to be set at the backplane of four batteries in the target photovoltaic component to obtain the backplane temperature of the four batteries; step S122: using an infrared camera to obtain a temperature distribution diagram of all batteries of the target photovoltaic component; step S123: using the obtained backplane temperature of the four batteries as an anchor point, and according to the temperature distribution of all batteries of the target photovoltaic component, to obtain the accurate backplane temperature of all batteries of all target photovoltaic components.

[0010] In an example of the method for determining the conversion temperature provided in the above aspect, the temperature sensor in step S121 is a Pt100 temperature sensor.

[0011] In an example of the conversion temperature determination method provided in the above aspect, the step S122 specifically includes: the angle between the shooting direction of the infrared camera and the discovery direction of the front glass of the target photovoltaic component is 30°, the distance between the lens of the infrared camera and the center point of the target photovoltaic component is 2 meters, and the infrared emissivity in the infrared camera is set to 0.9.

[0012] In an example of the conversion temperature determination method provided in the above aspect, the step S13 includes: step S131: obtaining the inclined surface irradiance data received by the target photovoltaic component; step S132: obtaining the ambient temperature data where the target photovoltaic component is installed; step S133: obtaining the wind speed data received by the target photovoltaic component.

[0013] In an example of the conversion temperature determination method provided in the above aspect, the step S131 specifically includes: the radiometer for measuring the irradiance of the inclined surface is a silicon-based radiometer, and the installation angle of the radiometer differs from the installation angle of the target photovoltaic module by no more than ±0.5°.

[0014] In an example of the conversion temperature determination method provided in the above aspect, the step S132 specifically includes: the device for measuring the ambient temperature is a Pt100 temperature sensor, the measurement location of the Pt100 temperature sensor is no more than 5 meters away from the target photovoltaic component installation location, and the Pt100 temperature sensor needs to be shielded from light and wind.

[0015] In an example of the conversion temperature determination method provided in the above aspect, the step S133 specifically includes: the distance between the measurement location of the wind speed measuring instrument for measuring the wind speed data and the installation location of the target photovoltaic component is not more than 15 meters, the wind speed measuring instrument is not blocked by wind, and the difference between the measurement height of the wind speed measuring instrument and the installation height of the target photovoltaic component is not more than 1 meter.

[0016] In an example of the conversion temperature determination method provided in the above aspect, the temperature conversion model is composed of a junction temperature model and a mismatch compensation model.

[0017] Beneficial effects: The method for determining the conversion temperature of a photovoltaic module of the present invention can effectively solve the problem that the conversion temperature of a target photovoltaic module cannot be determined when the tester performs IEC 60891 conversion on the current-voltage (IV) characteristic curve of the target photovoltaic module outdoors, realizes accurate and convenient conversion of the IV characteristic curve of the photovoltaic module, solves the key technical problems in the IEC60891 procedure of the photovoltaic module, and provides effective technical support for the tester's work after the conversion. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other aspects, features and advantages of the embodiments of the present invention will become more apparent through the following description in conjunction with the accompanying drawings, in which:

[0019] Figure 1 is a schematic structural diagram of an example of a target photovoltaic component targeted by the method for determining the conversion temperature of a photovoltaic component according to an embodiment of the present invention;

[0020] Figure 2 is a flow chart of a method for determining a conversion temperature of a photovoltaic module according to an embodiment of the present invention;

[0021] Figure 3 This is a comparison chart of the backplane temperature of a target photovoltaic module with uniform temperature distribution under different inclined surface irradiances and the cell junction temperature obtained by the junction temperature model;

[0022] Figure 4 This is a comparison chart of the relative error of the battery junction temperature obtained by the junction temperature model under IEC 60891 conversion to standard test conditions and the relative error of the battery junction temperature obtained by the backplane temperature under IEC 60891 conversion to standard test conditions;

[0023] Figure 5 This is a comparison chart of the relative error of the battery junction temperature obtained by using the mismatch compensation model to convert IEC 60891 to standard test conditions and the relative error of the backplane temperature to convert IEC 60891 to standard test conditions. DETAILED DESCRIPTION

[0024] Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention may be implemented in many different forms, and the present invention should not be construed as being limited to the specific embodiments set forth herein. On the contrary, these embodiments are provided to explain the principles of the present invention and their practical applications, so that other persons skilled in the art can understand the various embodiments of the present invention and various modifications suitable for specific intended applications.

[0025] As used herein, the term "including" and its variations represent open terms, meaning "including but not limited to". The terms "based on", "according to", etc. mean "based at least in part on", "based at least in part on". The terms "one embodiment" and "an embodiment" mean "at least one embodiment". The term "another embodiment" means "at least one other embodiment". The terms "first", "second", etc. may refer to different or the same objects. Other definitions may be included below, whether explicit or implicit. Unless the context clearly indicates otherwise, the definition of a term is consistent throughout the specification.

[0026] The terms "exemplary," "example," and the like used throughout this specification mean "used as an example, instance, or illustration" and do not mean "preferred" or "advantageous" over other embodiments. The detailed description includes specific details for the purpose of providing an understanding of the described techniques. However, these techniques can be implemented without these specific details. In some instances, in order to avoid obscuring the concepts of the described embodiments, well-known structures and devices are shown in block diagram form.

[0027] Figure 1 1 is a schematic diagram of an example of a target photovoltaic module for which the conversion temperature determination method of a photovoltaic module according to an embodiment of the present invention is directed. It should be understood that the structure of the target photovoltaic module here is only an example, and the conversion temperature determination method of a photovoltaic module according to an embodiment of the present invention is not only directed to the photovoltaic module of this structure.

[0028] Reference Figure 1 The front and back sides of the solar cell 3 (which is composed of a plurality of single solar cells) are respectively combined with the front glass 1 and the back glass 4 through the EVA adhesive film 2.

[0029] Figure 2 is a flow chart of a method for determining a conversion temperature of a photovoltaic module according to an embodiment of the present invention.

[0030] Reference Figure 2 , in step S1, the operating data of the target photovoltaic module is obtained.

[0031] Furthermore, the step S1 includes step S11, step S12 and step S13.

[0032] Specifically, in step S11, current-voltage (IV) characteristic curve data of the target photovoltaic module is obtained.

[0033] In step S12, accurate backplane temperature data of all cells (all single cells) of the target photovoltaic module are obtained.

[0034] Specifically, the step S12 includes: step S121: using a temperature sensor to be set at the back plates of the four batteries in the target photovoltaic module (i.e., the back plates corresponding to the four single batteries) to obtain the back plate temperature of the four batteries; step S122: using an infrared camera to obtain a temperature distribution diagram of all batteries of the target photovoltaic module; step S123: using the obtained back plate temperature of the four batteries as an anchor point, and according to the temperature distribution of all batteries of the target photovoltaic module, to obtain the accurate back plate temperature of all batteries of all target photovoltaic modules.

[0035] In one example, the temperature sensor in step S121 is a Pt100 temperature sensor, but the present invention is not limited thereto.

[0036] In addition, the step S122 specifically includes: the angle between the shooting direction of the infrared camera and the discovery direction of the front glass of the target photovoltaic module is 30°, the distance between the lens of the infrared camera and the center point of the target photovoltaic module is 2 meters, and the infrared emissivity in the infrared camera is set to 0.9.

[0037] In step S13, environmental parameter data of the location where the target photovoltaic assembly is installed is obtained.

[0038] Specifically, the step S13 includes: step S131: acquiring the inclined surface irradiance data received by the target photovoltaic assembly; step S132: acquiring the ambient temperature data where the target photovoltaic assembly is installed; step S133: acquiring the wind speed data received by the target photovoltaic assembly.

[0039] In addition, the step S131 specifically includes: the radiometer for measuring the irradiance of the inclined surface is a silicon-based radiometer, and the installation angle of the radiometer differs from the installation angle of the target photovoltaic module by no more than ±0.5°.

[0040] The step S132 specifically includes: the device for measuring the ambient temperature is a Pt100 temperature sensor, the distance between the measurement location of the Pt100 temperature sensor and the target photovoltaic component installation location is no more than 5 meters, and the Pt100 temperature sensor needs to be shielded from light and wind.

[0041] The step S133 specifically includes: the distance between the measurement location of the wind speed measuring instrument for measuring wind speed data and the installation location of the target photovoltaic component is no more than 15 meters, the wind speed measuring instrument is not blocked by wind, and the difference between the measurement height of the wind speed measuring instrument and the installation height of the target photovoltaic component is no more than 1 meter.

[0042] Continue to refer to Figure 1In step S2, required electrical parameters are extracted according to the operating data of the target photovoltaic module.

[0043] In an example, the specific method for extracting the required electrical parameters can be performed with reference to the parameter extraction method of IEC 60891, which will not be described in detail here.

[0044] In step S3, the operating data and the extracted required electrical parameters are input into a conversion temperature model to obtain the conversion temperature of the target photovoltaic component.

[0045] Specifically, the conversion temperature model includes two parts: a junction temperature model and a mismatch compensation model. The junction temperature model corresponds to the problem of difference in backplane and battery temperature, while the mismatch compensation model corresponds to the mismatch problem between batteries. The construction of the conversion temperature model is described in detail below.

[0046] The transition temperature model can be expressed as the following Equation 1.

[0047]

[0048] Among them, T trans represents the conversion temperature of the target photovoltaic module, that is, the IV characteristic curve of the target photovoltaic module is converted to IEC 60891 using the temperature; T ave,j Represents the average value of the junction temperature of all cells (all single cells) in the target photovoltaic module; Indicates the temperature compensation for the mismatch loss caused by the uneven temperature between cells (between individual cells) in the target photovoltaic module; It indicates the degree of uneven temperature of the target photovoltaic module, that is, the relative variance of the temperature of all cells in the target photovoltaic module, specifically the proportion of the variance to the average value, in %.

[0049] First, for T in Equation 1 ave,j T ave,j It is based on the junction temperature model in the conversion temperature model, such as Figure 1As shown, the target photovoltaic module is a "sandwich" packaging structure, with a front glass 1 on the front, a solar cell 3 in the middle, and a back glass 4 on the back (it can also be a back panel, glass is used in this example), and the layers are sealed with EVA film 2 (the type of film is only a schematic, and the present invention is not limited to this). When the sun shines on the target photovoltaic module, it will heat the internal solar cell and raise its temperature to the highest in the target photovoltaic module. Heat conduction will occur between the internal layers of the target photovoltaic module, and heat energy will be conducted from the inner layer (solar cell) to the outer layer (glass on both sides). Afterwards, heat convection and heat radiation will occur between the target photovoltaic module and the external environment. The heat conduction between the solar cell junction temperature and the back panel temperature of the target photovoltaic module is expressed as the following formula 2.

[0050]

[0051] Among them, T j represents the junction temperature of one of the solar cells (a single solar cell) in the target photovoltaic module; T back It represents the back panel temperature of the solar cell corresponding to the solar cell; R represents the thermal resistance of the material from the back panel of the target photovoltaic module to the solar cell; τ represents the energy conversion rate, specifically the proportion of the part of the target photovoltaic module converted into thermal energy to the received solar energy; Area represents the front area of ​​the target photovoltaic module; G represents the inclined surface irradiance received by the target photovoltaic module.

[0052] The above equation 2 can be further expressed as the following equation 3.

[0053] ΔT=T j -T back =τ·Area·R·1 / 2·G (3)

[0054] Wherein, ΔT represents the difference between the solar cell junction temperature and the target photovoltaic module backplane temperature. τ, Area and R of the photovoltaic module are independent of the environmental parameters, so ΔT and G in equation 3 are linearly related. Therefore, the following equation 4 can be further obtained.

[0055]

[0056] Where, ΔT ref and G ref They represent the reference temperature difference (i.e., the reference temperature difference between the solar cell junction temperature and the backplane temperature of the target photovoltaic module) and the corresponding reference inclined surface irradiance, i.e., the inclined surface irradiance incident on the target photovoltaic module is G ref When the reference temperature difference is ΔT ref .

[0057] According to equation 3 and equation 4, we can get Tj With T back The relationship between and G is expressed as the following formula 5.

[0058]

[0059] The target photovoltaic module will have thermal convection and thermal radiation with the external environment. Thermal convection will be affected by wind, of which wind direction has little effect on thermal convection, and wind speed has the main influence on thermal convection; thermal radiation is determined by the backplane temperature and the ambient temperature, and follows the Stefan-Boltzmann law.

[0060] In summary, the junction temperature model of the target photovoltaic module can be expressed as the following equation 6.

[0061]

[0062] Where a, b1 and b2 represent the empirical coefficients of heat exchange, v wind Indicates wind speed, T a Indicates the ambient temperature.

[0063] By applying equation 6, the junction temperature T of the i-th solar cell in the target photovoltaic module can be obtained: j,i Then, the junction temperatures of all solar cells in the target photovoltaic module are calculated and the average value is obtained. The average value is expressed as the following formula 7.

[0064]

[0065] Wherein, n represents the number of solar cells (single solar cells) in the target photovoltaic module.

[0066] The above content is the junction temperature model part of the conversion temperature model of the present invention.

[0067] Next, in equation 1 item for description. It is a mismatch compensation model based on the conversion temperature model. Due to inconsistent temperatures, the solar cells (between individual cells) inside the photovoltaic module will have inter-cell mismatch. Specifically, some solar cells in the photovoltaic module cannot operate at the maximum power point, resulting in power loss. The traditional method is to use the average temperature of the four cells in the photovoltaic module as the operating temperature of the photovoltaic module, but this method does not take the mismatch phenomenon into account and does not perform mismatch compensation temperature. According to an embodiment of the present invention, a compensation coefficient d is established, which is specifically expressed as the following formula 8.

[0068]

[0069] For the mismatch between cells caused by uneven temperature in the photovoltaic module, follow the mismatch formula proposed by Bucciarell. When the solar cells are connected in series or in parallel, there is a mismatch formula, which is expressed as the following equation 9 and equation 10.

[0070]

[0071]

[0072] Wherein, Series Loss (%) represents the series mismatch coefficient; represents the variance of the maximum power point current of the battery in the series circuit; N represents the number of batteries in series in a substring of the target photovoltaic module. Parallel Loss (%) represents the parallel mismatch coefficient; represents the variance of the maximum power point voltage between substrings in the parallel circuit; M represents the number of substrings in the target photovoltaic module. c is a dimensionless constant and can be expressed as the following formula 11.

[0073]

[0074] Among them, V oc represents the open circuit voltage of the target photovoltaic module; V mp represents the maximum power point voltage of the target photovoltaic module.

[0075] It can be seen from equations 9 and 10 that the mismatch coefficient is The relationship is linear. Based on the battery diode equation, and The relationship formula.

[0076] The single diode equation of a solar cell is expressed as the following equation 12.

[0077]

[0078] Among them, i ph represents the photocurrent, i0 represents the saturation current, n represents the diode ideality factor, k represents the Boltzmann constant, q represents the electron charge, and r s represents the series resistance, r sh represents the parallel resistance and T represents the temperature.

[0079] Equation 12 is an implicit equation and cannot obtain the relationship between the current-voltage (iv) characteristic of the battery and the junction temperature. Using the Lambert W equation, Equation 12 can be rewritten as an explicit equation, which is expressed as the following Equations 13 and 14.

[0080]

[0081]

[0082] The iv characteristic of a solar cell satisfies the following equation 15 at the maximum power point.

[0083]

[0084] According to equations 13, 14 and 15, we can get i mp , v mp The linear relationship between and T is expressed as the following equations 16 and 17.

[0085]

[0086]

[0087] Where ω=W{i ph q / i0}.

[0088] Since the temperature difference between single cells is small, n, r s , r sh and ω are both constants. Therefore, from equations (16) and (17), we can further obtain the value of all cells in the target photovoltaic module: and , and is expressed as the following equations 18 and 19.

[0089]

[0090]

[0091] According to equation 9, equation 10, equation 18 and equation 19, the power loss of the target photovoltaic module can be obtained, which is expressed as the following equation 20.

[0092]

[0093] Based on equation 8 and equation 20, temperature compensation due to temperature inconsistency between batteries (single cells) can be obtained, which is expressed as the following equation 21.

[0094]

[0095] Furthermore, by substituting equation 7 and equation 21 into equation 1, the conversion temperature of the target photovoltaic module at the current moment can be obtained, which is expressed as the following equation 22.

[0096]

[0097] The experimental results of the experiment conducted using the method for determining the conversion temperature according to the embodiment of the present invention are described in detail below.

[0098] Thousands of IV characteristic curves under various weather conditions and different temperature distribution conditions are used as examples for illustration. The conversion temperature obtained by the conversion temperature determination method according to the embodiment of the present invention and the conversion temperature obtained by the traditional method are input into the IEC60891 conversion program, and the above IV characteristic curve is converted to standard test conditions (STC). The converted IV characteristic curve is compared with the IV characteristic curve measured under STC to verify the feasibility and superiority of the proposed method.

[0099] 1) The target photovoltaic module with uniform temperature distribution Used to verify the accuracy of the junction temperature model. Taking the equivalent battery temperature in IEC 60904-5 as the true value, the backplane temperature of the target photovoltaic module with uniform temperature distribution under different inclined surface irradiances is compared with the battery junction temperature obtained by the junction temperature model. The results are as follows Figure 3 shown. Figure 3 The results show that, taking the equivalent battery temperature as the true value, the relative error of the battery junction temperature obtained by the junction temperature model is between 0.5% and 1%, which is significantly better than the relative error of the backplane temperature: 4% to 7%.

[0100] The IV characteristic curves of the target PV modules with uniform temperature distribution at different equivalent battery temperatures are converted to standard test conditions using the temperatures obtained by different methods according to IEC 60891, and the relative errors between the two are compared. The results are as follows: Figure 4 shown. Figure 4 The results show that the relative error of the battery junction temperature obtained by the junction temperature model for IEC 60891 conversion to standard test conditions is within 1%, which is significantly better than the IEC 60891 conversion to standard test conditions using the backplane temperature: 2% to 5%.

[0101] 2) The target photovoltaic module with uneven temperature distribution It is used to verify the accuracy of the mismatch compensation model. The target photovoltaic module with uneven temperature distribution is placed under different degrees of temperature unevenness ( The IV characteristic curves obtained by using different temperatures are converted from IEC 60891 to standard test conditions, and the relative errors between the two are compared. The results are as follows Figure 5 shown. Figure 5 The results show that the relative error of using the conversion temperature obtained by the mismatch compensation model to convert IEC 60891 to standard test conditions is around 1%, which is significantly better than using the backplane temperature to convert IEC 60891 to standard test conditions: 3% to 8%.

[0102] In summary, the method for determining the conversion temperature of a photovoltaic module according to an embodiment of the present invention can effectively solve the problem that the conversion temperature of a target photovoltaic module cannot be determined when the tester performs IEC 60891 conversion on the current-voltage (IV) characteristic curve of the target photovoltaic module outdoors, thereby achieving accurate and convenient conversion of the IV characteristic curve of the photovoltaic module, solving the key technical problems in the IEC 60891 procedure of the photovoltaic module, and providing effective technical support for the tester's work after the conversion.

[0103] The optional implementation modes of the embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above implementation modes. Within the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all belong to the protection scope of the embodiments of the present invention.

Claims

1. A method for determining the conversion temperature of a photovoltaic module, characterized in that: The conversion temperature determination method comprises: Step S1: obtaining the operating data of the target photovoltaic module; Step S2: extracting required electrical parameters according to the operating data; Step S3: inputting the operating data and the extracted required electrical parameters into a conversion temperature model to obtain the conversion temperature of the target photovoltaic module.

2. The method for determining the conversion temperature according to claim 1, characterized in that: The step S1 comprises: Step S11: acquiring current-voltage characteristic curve data of the target photovoltaic module; Step S12: Acquire accurate backplane temperature data of all cells of the target photovoltaic module; Step S13: Acquire environmental parameter data of the location where the target photovoltaic assembly is installed.

3. The method for determining the conversion temperature according to claim 2, characterized in that: The step S12 comprises: Step S121: using a temperature sensor disposed at the back plates of four cells in the target photovoltaic assembly to obtain the back plate temperatures of the four cells; Step S122: using an infrared camera to obtain a temperature distribution diagram of all cells of the target photovoltaic module; Step S123: taking the obtained backplane temperatures of the four cells as anchor points and obtaining accurate backplane temperatures of all cells of all target photovoltaic modules according to the temperature distribution conditions of all cells of the target photovoltaic modules.

4. The method for determining the conversion temperature according to claim 3, characterized in that: The temperature sensor in step S121 is a Pt100 temperature sensor.

5. The method for determining the conversion temperature according to claim 3, characterized in that: The step S122 specifically includes: the angle between the shooting direction of the infrared camera and the discovery direction of the front glass of the target photovoltaic module is 30°, the distance between the lens of the infrared camera and the center point of the target photovoltaic module is 2 meters, and the infrared emissivity in the infrared camera is set to 0.

9.

6. The method for determining the conversion temperature according to claim 2, characterized in that: The step S13 comprises: Step S131: acquiring the inclined surface irradiance data received by the target photovoltaic assembly; Step S132: Acquire the ambient temperature data of the location where the target photovoltaic assembly is installed; Step S133: obtaining wind speed data received by the target photovoltaic assembly.

7. The method for determining the conversion temperature according to claim 6, characterized in that: The step S131 specifically includes: the radiometer for measuring the irradiance of the inclined surface is a silicon-based radiometer, and the installation angle of the radiometer differs from the installation angle of the target photovoltaic module by no more than ±0.5°.

8. The method for determining the conversion temperature according to claim 6, characterized in that: The step S132 specifically includes: the device for measuring the ambient temperature is a Pt100 temperature sensor, the distance between the measurement location of the Pt100 temperature sensor and the target photovoltaic component installation location is no more than 5 meters, and the Pt100 temperature sensor needs to be shielded from light and wind.

9. The method for determining the conversion temperature according to claim 6, characterized in that: The step S132 specifically includes: the distance between the measurement location of the wind speed measuring instrument for measuring the wind speed data and the installation location of the target photovoltaic component is no more than 15 meters, the wind speed measuring instrument is not blocked by wind, and the difference between the measurement height of the wind speed measuring instrument and the installation height of the target photovoltaic component is no more than 1 meter.

10. The method for determining the conversion temperature according to claim 1, characterized in that: The temperature conversion model is composed of a junction temperature model and a mismatch compensation model.

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