Potential-induced degradation detection method of photovoltaic module

Abstract

The invention relates to the technical field of attenuation detection of photovoltaic modules, and discloses a potential-induced attenuation detection method of a photovoltaic module, which comprises the following steps: by taking a module packaging layer of the photovoltaic module as a working electrode, measuring the ion mobility of the module packaging layer of the photovoltaic module with different potential-induced attenuation rates through a preset standard electrochemical measurement process; constructing a migration rate-attenuation rate correlation model of the photovoltaic module; measuring the ion mobility of the to-be-measured photovoltaic module through a preset standard electrochemical measurement process by taking the module packaging layer of the to-be-measured photovoltaic module as a working electrode; substituting the ion mobility of the to-be-detected photovoltaic module into the mobility-attenuation rate correlation model, and calculating a potential-induced attenuation rate quantized value of the to-be-detected photovoltaic module; and judging the attenuation grade of the to-be-detected photovoltaic module according to the grade judgment threshold range in which the quantized value of the potential-induced attenuation rate of the to-be-detected photovoltaic module falls. According to the method, quantitative rating of the PID fault degree of the photovoltaic module can be realized with relatively low cost and relatively high efficiency.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic module power attenuation detection technology, and specifically to a potential-induced attenuation detection method for photovoltaic modules. Background Technology

[0002] As the core energy conversion unit of a solar power generation system, the long-term reliability of photovoltaic modules directly determines the power generation efficiency and return on investment of the power plant. With the large-scale development of photovoltaic power plants and the extension of module service life, potential-induced degradation (PID) faults have become a core issue restricting module reliability. This fault is caused by Na+ in the module encapsulation layer. + K + Migratory ions migrate to and deposit on the surface of the solar cells under bias voltage, resulting in a continuous decline in module power over service life. In severe cases, the power decline can reach more than 30% within 1-2 years, causing huge economic losses to the power plant.

[0003] Existing methods for detecting PID (Potential Ingress and Degradation) faults in photovoltaic (PV) modules mainly include power comparison, infrared thermography, electrochemical impedance spectroscopy, and photochromatography. These methods all suffer from drawbacks such as inability to quantify the degree of degradation, significant environmental influence during the detection process, large detection errors, slow detection efficiency, high detection costs, and / or potential damage to the modules. Therefore, a new PID fault detection method for PV modules that can overcome these problems is needed. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a method for detecting the potential-induced degradation of photovoltaic modules, which can quickly and cost-effectively quantify and evaluate the degree of potential-induced degradation of photovoltaic modules, and has high reliability.

[0005] To solve the above problems, the technical solution adopted by the present invention is as follows: A method for detecting potential-induced degradation of photovoltaic modules, comprising the following steps: Using the module encapsulation layer of a photovoltaic module as the working electrode, the ion mobility of the module encapsulation layer of a photovoltaic module with different potential-induced degradation rates is measured through a preset standard electrochemical measurement procedure, and a mobility-degradation rate correlation model of the photovoltaic module is constructed. The module encapsulation layer of the photovoltaic module under test is used as the working electrode, and the ion mobility of the photovoltaic module under test is measured through a preset standard electrochemical measurement procedure. Substitute the ion mobility of the photovoltaic module under test into the mobility-degradation rate correlation model to calculate the potential-induced degradation rate quantification value of the photovoltaic module under test. The degradation level of the photovoltaic module under test is determined based on the threshold range into which the quantified value of the potential-induced degradation rate falls.

[0006] Compared to existing technologies, the advantages of this invention are as follows: This method, by statistically constructing a mobility-degradation rate correlation model between ion mobility and power degradation rate, achieves a quantitative assessment of the PID (Potential Influence of Processing) fault level of photovoltaic (PV) modules. This provides maintenance personnel with quantifiable PID fault level data as support for maintenance, reducing the operating costs of solar power systems. This method only requires placing the PV module in an electrolyte and placing the counter electrode on the surface of the module's encapsulation layer to quantitatively detect the PID level. The detection does not damage the PV module, and the module can be directly reused after detection. Furthermore, the detection efficiency is high, meeting the quarterly inspection needs of PV power plants with fewer maintenance personnel.

[0007] The above-mentioned method for detecting potential-induced degradation of photovoltaic modules, wherein the standard electrochemical measurement procedure includes: Multiple photovoltaic modules from the same batch as the photovoltaic modules to be tested are taken as photovoltaic module samples. The ion concentration of the module encapsulation layer of the photovoltaic module samples is measured by titration. The average ion concentration of the multiple photovoltaic module samples is taken as the batch ion concentration value of the photovoltaic modules in that batch. Wipe the surface of the encapsulation layer of the photovoltaic module under test in the same direction to clean the encapsulation layer of the photovoltaic module under test; Mark a flat, undamaged area of ​​a predetermined size in the center of the encapsulation layer of the photovoltaic module under test as the marking area; Place the photovoltaic module to be tested into the electrolyte, and arrange the counter electrodes of the electrochemical workstation on the marked area according to the preset counter electrode setting parameters; The preset detection parameters are entered into the electrochemical workstation, and the environmental parameters are measured by the environmental sensor. When the environmental parameters fall within the preset environmental parameter threshold range, the electrochemical workstation is started to apply voltage to the module encapsulation layer of the photovoltaic module under test. Monitor and record the average current and environmental parameter values ​​within a preset measurement period after the current stabilizes; The mean current value is corrected based on the environmental parameter values ​​to obtain the corrected current value under standard environmental parameters; The ion mobility of the photovoltaic module under test is calculated based on the corrected current value, the counter electrode parameters, and the batch ion concentration value.

[0008] In the above-mentioned method for detecting potential-induced degradation of photovoltaic modules, the step of calculating the ion mobility of the photovoltaic module under test based on the corrected current value, the counter electrode parameters, and the batch ion concentration value is performed by calculating the ion mobility μ of the photovoltaic module under test using the following formula: μ=(L×I_correction) / (A×C×U) Where L is the distance between the counter electrodes, I_correction is the correction current value, A is the contact area between the counter electrode and the module encapsulation layer, C is the batch particle concentration value, and U is the bias voltage applied to the module encapsulation layer through the counter electrode.

[0009] The above-mentioned method for detecting potential-induced degradation of photovoltaic modules includes environmental parameter threshold ranges including temperature parameter threshold ranges and humidity parameter threshold ranges. The temperature parameter threshold range is 23-27℃, and the humidity parameter threshold range is 45%-55%RH.

[0010] The above-mentioned method for detecting potential-induced degradation of photovoltaic modules includes the following detection parameters: a linear boost type of 0-1000V, a boost rate of 5V / s, a maintenance period of 30s after boosting, a sampling frequency of 1Hz, and a measurement time period of 25s after boosting.

[0011] The above-mentioned method for detecting potential-induced degradation of photovoltaic modules includes the following electrode setting parameters: the distance between the counter electrodes is 5 cm, the tilt angle between the counter electrodes and the module encapsulation layer is less than or equal to 3°, and the contact pressure between the counter electrodes and the module encapsulation layer is 0.3 MPa.

[0012] In the above-mentioned method for detecting potential-induced degradation of photovoltaic modules, in the step of monitoring and recording the average current and environmental parameter values ​​within a preset measurement period after the current stabilizes, if a single fluctuation of the current detected within the measurement period is greater than 10%, it is determined that the contact of the counter electrode is abnormal, the detection is suspended, and the counter electrode is rearranged.

[0013] The above-mentioned method for detecting potential-induced degradation of photovoltaic modules, after the step of monitoring and recording the average current and environmental parameter values ​​within a preset measurement time period after the current stabilizes, further includes: If the difference between the average current of the photovoltaic module under test and the average reference current of a non-degrading photovoltaic module of the same model measured by a standard electrochemical measurement procedure exceeds the preset deviation threshold, the contact status between the counter electrode and the module encapsulation layer of the photovoltaic module under test needs to be checked.

[0014] The above-mentioned method for detecting potential-induced degradation of photovoltaic modules is characterized in that, after the step of monitoring and recording the average current value and environmental parameter values ​​within a preset measurement time period after the current stabilizes, it further includes: If the average current of the photovoltaic module under test exceeds the preset normal current threshold range, the test is stopped, and the following checks are made: whether there is a short circuit in the counter electrode, whether the module encapsulation layer of the photovoltaic module under test is damaged, whether the contact pressure between the counter electrode and the module encapsulation layer reaches the required value, and whether the bias output of the electrochemical workstation is normal.

[0015] The above-mentioned method for detecting potential-induced degradation of photovoltaic modules, before the steps of inputting preset detection parameters into an electrochemical workstation, measuring environmental parameters through an environmental sensor, and applying voltage to the module encapsulation layer of the photovoltaic module under test by starting the electrochemical workstation when the environmental parameters fall within a preset environmental parameter threshold range, further includes: The environmental sensors are calibrated using a standard temperature and humidity source.

[0016] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0017] Figure 1 This is a flowchart of a photovoltaic module potential-induced degradation detection method according to an embodiment of the present invention.

[0018] Figure 2 This is a flowchart of the standard electrochemical measurement procedure according to an embodiment of the present invention. Detailed Implementation

[0019] The embodiments of the present invention are described in detail below, with reference to... Figure 1 The present invention provides a method for detecting the potential-induced degradation of a photovoltaic module, which specifically includes the following steps: Using the module encapsulation layer of a photovoltaic module as the working electrode, the ion mobility of the module encapsulation layer of a photovoltaic module with different potential-induced degradation rates is measured through a preset standard electrochemical measurement procedure, and a mobility-degradation rate correlation model of the photovoltaic module is constructed. The module encapsulation layer of the photovoltaic module under test is used as the working electrode, and the ion mobility of the photovoltaic module under test is measured through a preset standard electrochemical measurement procedure. Substitute the ion mobility of the photovoltaic module under test into the mobility-degradation rate correlation model to calculate the potential-induced degradation rate quantification value of the photovoltaic module under test. The degradation level of the photovoltaic module under test is determined based on the threshold range into which the quantified value of the potential-induced degradation rate falls.

[0020] The PID fault is caused by Na in the component encapsulation layer. + K +The ion mobility of the encapsulation layer, caused by the migration and deposition of mobile ions to the surface of the solar cell under bias voltage, can reflect the degradation rate (PID) of the photovoltaic module. This method measures the ion mobility of the encapsulation layer of a large number of identical modules with power degradation rates tested using the solar simulator power test method according to ASTM E1036-15 standard, employing a pre-defined standard electrochemical measurement procedure. A migration-degradation rate correlation model is then fitted based on the data using statistical methods to quantitatively assess the degradation rate of the photovoltaic module under test. The measurement of the ion mobility of the photovoltaic module under test also uses a pre-defined standard electrochemical measurement procedure to eliminate external interference and ensure the traceability and reproducibility of the test data, meeting the standardized requirements of photovoltaic industry testing and certification. This method treats photovoltaic (PV) modules as an "electrochemical system" and uses a three-electrode system, with the module encapsulation layer as the working electrode. It measures the ion mobility of the encapsulation layer using electrochemical measurements. The measurement process only requires placing the counter electrode on the encapsulation layer, without damaging the PV module. After testing, the PV module can be directly returned to its original state. The testing process is simple, requiring neither module disassembly nor large-scale testing equipment; only an electrochemical workstation is needed, resulting in lower testing costs compared to traditional methods. Scale-up validation shows that this method allows a maintenance team of approximately 30 people to meet the quarterly testing needs of a 100MW PV power plant, adapting to the large-scale maintenance scenarios of large PV power plants. It provides PV power plant maintenance personnel with reliable and quantifiable PID (Potential Indicator) levels of PV modules, offering reliable data support for proactive maintenance and reducing the operating costs of PV power plants.

[0021] Reference Figure 2 In this embodiment, in order to eliminate external influences during the ion mobility measurement process, meet the standardized requirements for testing and certification in the photovoltaic industry, and facilitate training for new operation and maintenance personnel, the standard electrochemical measurement procedure includes the following steps: First, it is necessary to measure the ion concentration of the encapsulation layer of the photovoltaic module batch to be tested. Specifically, at least three photovoltaic modules from the batch to be tested are taken as photovoltaic module samples, and the ion concentration of the encapsulation layer of the photovoltaic module samples is measured by titration. The average ion concentration of the three photovoltaic module samples is taken as the batch particle concentration value of the photovoltaic module, so as to calculate the ion mobility of the encapsulation layer of the module based on the detected current.

[0022] Subsequently, the photovoltaic modules to be tested are pre-treated. Specifically, a lint-free cloth soaked in anhydrous ethanol is used to wipe the surface of the module encapsulation layer of the photovoltaic module to be tested. During the wiping process, it is necessary to wipe in the same direction to avoid scratches, so as to clean the module encapsulation layer of the photovoltaic module to be tested. After cleaning, a flat, undamaged area of ​​a predetermined size needs to be marked in the center of the encapsulation layer of the photovoltaic module to be tested. This area will serve as the deployment area for the counter electrode. The marked area should avoid the frame and junction box of the photovoltaic module, and the encapsulation layer within the marked area must be undamaged.

[0023] Subsequently, the photovoltaic module under test is placed in the electrolyte, and the counter electrodes of the electrochemical workstation are deployed on the marked area according to the preset counter electrode setting parameters. In this embodiment, the counter electrode setting parameters include: a distance of 5 cm between the two probes of the counter electrode, a contact pressure of 0.3 MPa between the probe and the module encapsulation layer, and an inclination angle of less than or equal to 3° between the probe and the encapsulation layer. The two probes of the counter electrode are fixed by two insulated adjustable brackets. The deployment parameters of the two probes are adjusted to meet the counter electrode setting parameter requirements. During the adjustment process, a pressure gauge monitors the contact pressure between the probe and the encapsulation layer in real time to ensure that the probe and the module encapsulation layer are fully in contact without damaging the module encapsulation layer. In this embodiment, to facilitate the alignment of the two probes of the electrode at 5 cm intervals, the preset size of the marked area is 5×5 cm.

[0024] Then, the preset detection parameters are entered into the electrochemical workstation, and environmental parameters are measured using an environmental sensor. Once the environmental parameters stabilize within the preset environmental parameter threshold range, the electrochemical workstation is activated to apply a bias voltage to the encapsulation layer of the photovoltaic module under test. In this embodiment, the detection parameters include: linear boost mode, bias range of 0-1000V, boost rate of 5V / s, voltage maintained at 1000V for 30s, and sampling frequency of 1Hz. The environmental sensor is a temperature and humidity sensor, with 25℃ temperature and 50%RH humidity as standard environmental parameters. Therefore, the bias voltage can only be applied to the encapsulation layer after the actual ambient temperature stabilizes within the temperature parameter threshold range of 25℃±2℃ and the actual ambient humidity stabilizes within the humidity parameter range of 50%±5%RH. This ensures that when the measured current is corrected to the standard environmental parameters, the error between the corrected current value calculated by the correction formula and the actual current value is within an acceptable range. In this embodiment, to ensure the accuracy of the measured temperature and humidity, the environmental sensor needs to be calibrated using a standard temperature and humidity source.

[0025] After the voltage boost is complete, the average current and environmental parameter values ​​are monitored and recorded within a preset measurement period after the current stabilizes. In this embodiment, to ensure the accuracy of the measured current values, after the voltage boost is complete, the data from the first 5 seconds of the transition phase after the boost is complete are removed, and the remaining 25 seconds are taken as the measurement period. The average current value of the photovoltaic module under test is then taken from the average current value of the remaining 25 seconds. Similarly, the environmental parameter values ​​are also taken from the average value of the remaining 25 seconds.

[0026] Subsequently, the average current is corrected according to the environmental parameter values ​​using a correction formula to obtain the corrected current value under standard environmental parameters. In this embodiment, the correction formula is: I_correction = I_measured × [1 + temperature correction coefficient × (25-T) + humidity correction coefficient × (50-H)], where I_correction is the corrected current value, I_measured is the average current value, T is the ambient temperature value in the environmental parameter values, and H is the ambient humidity value in the environmental parameter values.

[0027] Finally, the ion mobility of the photovoltaic module under test is calculated based on the corrected current value, the counter electrode parameters, and the batch particle concentration value. In this embodiment, the ion mobility μ is calculated using the following formula: μ=(L×I_corrected) / (A×C×U), where L is the counter electrode spacing, A is the contact area between the counter electrode and the module encapsulation layer, C is the batch particle concentration value, and U is the bias voltage applied to the module encapsulation layer through the counter electrode.

[0028] In some embodiments, to further ensure the accuracy of the measured ion mobility value of the photovoltaic module under test, after obtaining the average current of the photovoltaic module under test, it is necessary to compare the difference between the average current of the photovoltaic module under test and the average reference current measured by a non-degrading photovoltaic module of the same model through a standard electrochemical measurement procedure. If the error between the average current of the photovoltaic module under test and the average reference current exceeds 5% of the average current, there may be poor contact between the electrode and the module encapsulation layer. It is necessary to check the contact status between the probe and the module encapsulation layer, and remeasure after the test is completed. If the environmental parameter values ​​fluctuate drastically during the test, such as a temperature fluctuation of more than 5 degrees Celsius or a humidity fluctuation of more than 10%RH within ten minutes, the test needs to be paused, the portable constant temperature and humidity chamber turned on, and the measurement re-measured after the environmental parameter values ​​stabilize. Here, a non-degrading photovoltaic module refers to a photovoltaic module with a degradation rate of less than 0.5% verified by the ASTM E1036-15 standard.

[0029] During the measurement process, if the average current value within the last 25 seconds significantly exceeds the normal range (i.e., exceeds the preset normal current threshold), the measurement must be stopped. If the average current value is greater than 0.1A (i.e., the current value is far beyond the normal range), there may be a short circuit in the probe of the electrode or internal damage to the photovoltaic module under test. It is necessary to check whether there is a short circuit in the probe and whether the encapsulation layer is damaged. Replace the probe or the photovoltaic module and then measure again. If the average current value is less than 0.005A (i.e., the current value is far below the normal range), there may be poor probe contact or unsuccessful application of bias voltage. Check and adjust the contact pressure of the probe and whether the bias voltage output of the electrochemical workstation is normal. After troubleshooting, measure again. If the current changes by more than 20% during the detection process, such as from 0.02A to 0.04A, it may indicate a sudden change in the probe contact state or local damage to the component encapsulation layer. In this case, the probe needs to be repositioned and the surface of the component encapsulation layer needs to be checked. Then, the current value should be retested in segments, such as collecting data every 10 seconds. If the segmented data is stable, the average current value of the stable segment should be calculated.

[0030] In this embodiment, if the degradation rate of the photovoltaic module calculated by substituting the ion mobility into the mobility-degradation rate correlation model is less than or equal to 2%, the photovoltaic module is determined to be normal; if the degradation rate is greater than 2% and less than or equal to 10%, the photovoltaic module is determined to be slightly degraded; if the degradation rate is greater than 10%, the photovoltaic module is determined to be moderately or severely degraded. For ion mobility greater than 10 × 10 -8 A photovoltaic module with a degradation rate of cm² / (V·s) far exceeding the moderate degradation threshold may have severe aging or ion contamination issues in its encapsulation layer. It needs to be tested twice. If the results of the two tests are consistent, and the module exhibits signs of severe degradation such as yellowing of the encapsulation layer, it is marked as severely degraded. Furthermore, three modules from the same batch need to be tested simultaneously to rule out batch-wide issues. For example, a mobility of less than 0.5 × 10⁻⁶... -8 If the value of cm² / (V·s) is far below the normal range, the photovoltaic module may be a module with special low ion content encapsulation material, or there may be an abnormality in probe calibration. It is necessary to calibrate the probe with a standard non-attenuation module and perform a random test, or check the module encapsulation material specifications to confirm the ion content. If the data from the random test after calibration are consistent, the photovoltaic module is judged to be in excellent condition, that is, the attenuation rate is less than 0.5%.

[0031] In this embodiment, the method is implemented using a Chenhua CHI660E electrochemical workstation (version V2.8) and an SHT30 high-precision temperature and humidity sensor as environmental sensors. A platinum counter electrode with a precision of 0.01Ω and a tip diameter of 0.5cm (FLUKE 5720A) is used to evaluate the PID degree of a TSM-450DEG module in a 100MW power plant. Statistical analysis shows that the mobility-degradation rate correlation model for this photovoltaic module is as follows: y = 0.002x² + 0.05x + 0.1, where y is the degradation rate (%) and x = μ × 10⁻¹⁰. 8 To facilitate the calculation of degradation rate, 30 photovoltaic module samples with different degradation levels were compared and verified using this method and the standard method, namely the solar simulator power test method of ASTM E1036-15. The verification results are shown in the table below: Table 1. Comparison and verification table between this method and the standard method.

[0032] As can be seen from the table, the average absolute error of this method compared to the standard method is only 0.08%, and the error rate is less than or equal to 2.1%, which meets the industry accuracy standard of less than or equal to 5% for PID fault quantification detection of photovoltaic modules.

[0033] It should be noted that in the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is mentioned, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0034] In the description of this invention, unless otherwise explicitly defined, terms such as "setting," "installing," and "connecting" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0035] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A method for detecting potential-induced degradation of a photovoltaic module, characterized in that, Includes the following steps: Using the module encapsulation layer of a photovoltaic module as the working electrode, the ion mobility of the module encapsulation layer of a photovoltaic module with different potential-induced degradation rates is measured through a preset standard electrochemical measurement procedure, and a mobility-degradation rate correlation model of the photovoltaic module is constructed. The module encapsulation layer of the photovoltaic module under test is used as the working electrode, and the ion mobility of the photovoltaic module under test is measured through a preset standard electrochemical measurement procedure. Substitute the ion mobility of the photovoltaic module under test into the mobility-degradation rate correlation model to calculate the potential-induced degradation rate quantification value of the photovoltaic module under test. The degradation level of the photovoltaic module under test is determined based on the threshold range into which the quantified value of the potential-induced degradation rate falls.

2. The method for detecting potential-induced degradation of photovoltaic modules according to claim 1, characterized in that, The standard electrochemical measurement procedure includes: Multiple photovoltaic modules from the same batch as the photovoltaic modules to be tested are taken as photovoltaic module samples. The ion concentration of the module encapsulation layer of the photovoltaic module samples is measured by titration. The average ion concentration of the multiple photovoltaic module samples is taken as the batch ion concentration value of the photovoltaic modules in that batch. Wipe the surface of the encapsulation layer of the photovoltaic module under test in the same direction to clean the encapsulation layer of the photovoltaic module under test; Mark a flat, undamaged area of ​​a predetermined size in the center of the encapsulation layer of the photovoltaic module under test as the marking area; Place the photovoltaic module to be tested into the electrolyte, and arrange the counter electrodes of the electrochemical workstation on the marked area according to the preset counter electrode setting parameters; The preset detection parameters are entered into the electrochemical workstation, and the environmental parameters are measured by the environmental sensor. When the environmental parameters fall within the preset environmental parameter threshold range, the electrochemical workstation is started to apply voltage to the module encapsulation layer of the photovoltaic module under test. Monitor and record the average current and environmental parameter values ​​within a preset measurement period after the current stabilizes; The mean current value is corrected based on the environmental parameter values ​​to obtain the corrected current value under standard environmental parameters; The ion mobility of the photovoltaic module under test is calculated based on the corrected current value, the counter electrode parameters, and the batch ion concentration value.

3. The method for detecting potential-induced degradation of photovoltaic modules according to claim 2, characterized in that, In the step of calculating the ion mobility of the photovoltaic module under test based on the corrected current value, the counter electrode parameters, and the batch ion concentration value, the ion mobility μ of the photovoltaic module under test is calculated using the following formula: μ=(L×I_correction) / (A×C×U) Where L is the distance between the counter electrodes, I_correction is the correction current value, A is the contact area between the counter electrode and the module encapsulation layer, C is the batch particle concentration value, and U is the bias voltage applied to the module encapsulation layer through the counter electrode.

4. The method for detecting potential-induced degradation of photovoltaic modules according to claim 2, characterized in that, The environmental parameter threshold ranges include temperature parameter threshold ranges and humidity parameter threshold ranges. The temperature parameter threshold range is 23-27℃, and the humidity parameter threshold range is 45%-55%RH.

5. The method for detecting potential-induced degradation of photovoltaic modules according to claim 2, characterized in that, The detection parameters include: a linear boost type of 0-1000V, a boost rate of 5V / s, a maintenance period of 30s after boosting, a sampling frequency of 1Hz, and a measurement time period of 25s after boosting.

6. The method for detecting potential-induced degradation of photovoltaic modules according to claim 2, characterized in that, The electrode setting parameters include: the electrode spacing is 5cm, the tilt angle between the electrode and the component encapsulation layer is less than or equal to 3°, and the contact pressure between the electrode and the component encapsulation layer is 0.3MPa.

7. The method for detecting potential-induced degradation of photovoltaic modules according to claim 2, characterized in that, In the step of monitoring and recording the average current and environmental parameter values ​​within a preset measurement period after the current stabilizes, if a single fluctuation of the current detected within the measurement period is greater than 10%, it is determined that the contact of the counter electrode is abnormal, the detection is suspended, and the counter electrode is rearranged.

8. The method for detecting potential-induced degradation of photovoltaic modules according to claim 2, characterized in that, The step of monitoring and recording the average current and environmental parameter values ​​within a preset measurement time period after the current stabilizes also includes: If the difference between the average current of the photovoltaic module under test and the average reference current of a non-degrading photovoltaic module of the same model measured by a standard electrochemical measurement procedure exceeds the preset deviation threshold, the contact status between the counter electrode and the module encapsulation layer of the photovoltaic module under test needs to be checked.

9. The method for detecting potential-induced degradation of photovoltaic modules according to claim 2, characterized in that, The step of monitoring and recording the average current and environmental parameter values ​​within a preset measurement time period after the current stabilizes also includes: If the average current of the photovoltaic module under test exceeds the preset normal current threshold range, the test is stopped, and the following checks are made: whether there is a short circuit in the counter electrode, whether the module encapsulation layer of the photovoltaic module under test is damaged, whether the contact pressure between the counter electrode and the module encapsulation layer reaches the required value, and whether the bias output of the electrochemical workstation is normal.

10. The method for detecting potential-induced degradation of photovoltaic modules according to claim 2, characterized in that, Before the step of inputting preset detection parameters into the electrochemical workstation, measuring environmental parameters through environmental sensors, and applying voltage to the module encapsulation layer of the photovoltaic module under test by starting the electrochemical workstation when the environmental parameters fall within the preset environmental parameter threshold range, the following steps are also included: The environmental sensors are calibrated using a standard temperature and humidity source.

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