JP2022177708A - Device and program for detecting deterioration - Google Patents

Abstract

To provide a device and program for detecting deterioration, which allow for discovering occurrence of the PID phenomenon in a solar cell module at an earlier stage.SOLUTION: A deterioration detection device 10 comprises: an acquisition unit 11A configured to acquire an AC circuit model of a solar cell module which enables reproduction of a Nyquist diagram obtained from an AC impedance measurement result of the solar cell module and includes parallel resistors; and a detection unit 11B configured to detect occurrence of a PID phenomenon from a state of decrease in resistance of the parallel resistors in the AC circuit model acquired by the acquisition unit 11A.SELECTED DRAWING: Figure 2

Description

The present invention relates to a deterioration detection device and a deterioration detection program.

Conventionally, the following techniques have been available as techniques capable of detecting the occurrence of a PID (Potential Induced Degradation) phenomenon in a solar cell module.

Patent Literature 1 discloses a solar battery panel inspection apparatus using electroluminescence (EL). This inspection apparatus includes an AC power supply that generates AC power for applying AC power to the solar cell panel, and a camera that photographs the surface of the solar cell panel. In this inspection apparatus, the AC power is set so that the AC impedance for inducing EL emission in the solar cell panel is 1 kΩ or more.

JP 2018-105680 A

However, when the occurrence of the PID phenomenon is detected from the decrease in the brightness of the EL emission according to the technique described in Patent Document 1, the decrease in the brightness of the EL emission in the initial stage of the occurrence of the PID phenomenon in the solar cell module is extremely weak. Therefore, there is a problem that early detection of the PID phenomenon is difficult.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a degradation detection device and a degradation detection program that can detect the occurrence of the PID phenomenon in a solar cell module at an early stage. .

The deterioration detection device according to claim 1 is capable of reproducing a Nyquist diagram obtained from measurement results of AC impedance for a solar cell module, and acquires an AC circuit model of the solar cell module having a parallel resistance. and a detection unit that detects the occurrence of a PID phenomenon from the state of decrease in the resistance value of the parallel resistor in the AC circuit model acquired by the acquisition unit.

According to the deterioration detection device of claim 1, the AC circuit model of the solar cell module, which can reproduce the Nyquist diagram obtained from the measurement result of the AC impedance of the solar cell module and has a parallel resistance, is acquired. Then, by detecting the occurrence of the PID phenomenon from the decrease in the resistance value of the parallel resistor in the acquired AC circuit model, the occurrence of the PID phenomenon in the solar cell module can be detected earlier.

The deterioration detection device according to claim 2 is the deterioration detection device according to claim 1, wherein the PID phenomenon occurs when the detection unit detects that the resistance value is equal to or less than a predetermined threshold value. detected.

According to the deterioration detection device of claim 2, by detecting that the PID phenomenon has occurred when the resistance value becomes equal to or less than a predetermined threshold value, the difference between the resistance value and the initial value is reduced. It is possible to detect the occurrence of the PID phenomenon in the solar cell module more easily than in the case of detecting the occurrence of the PID phenomenon when the threshold is equal to or greater than a predetermined threshold.

The deterioration detection device according to claim 3 is the deterioration detection device according to claim 1, wherein the detection unit detects that the difference between the resistance value and the initial value is equal to or greater than a predetermined threshold value. , to detect that the PID phenomenon has occurred.

According to the deterioration detection device of claim 3, when the difference between the resistance value and the initial value is greater than or equal to a predetermined threshold value, it is detected that the PID phenomenon has occurred, thereby increasing the resistance value. It is possible to detect the occurrence of the PID phenomenon in the solar cell module with higher accuracy than in the case of detecting the occurrence of the PID phenomenon when it becomes equal to or less than a predetermined threshold value.

Claim 4 is the degradation detection device according to any one of claims 1 to 3, further comprising a presenting unit for presenting a detection result by the detecting unit.

According to the deterioration detection device of claim 4, by presenting the detection result, the detection result can be easily grasped.

The deterioration detection program according to claim 5 obtains an AC circuit model of the solar cell module that can reproduce a Nyquist diagram obtained from the measurement result of AC impedance for the solar cell module and has a parallel resistance, A computer is caused to execute a process of detecting the occurrence of the PID phenomenon from the state of decrease in the resistance value of the parallel resistor in the acquired AC circuit model.

According to the deterioration detection program according to claim 5, an AC circuit model of the solar cell module that can reproduce the Nyquist diagram obtained from the measurement result of the AC impedance of the solar cell module and has a parallel resistance is obtained. Then, by detecting the occurrence of the PID phenomenon from the decrease in the resistance value of the parallel resistor in the acquired AC circuit model, the occurrence of the PID phenomenon in the solar cell module can be detected earlier.

As described above, according to the present invention, the occurrence of the PID phenomenon in a solar cell module can be discovered earlier.

It is a block diagram which shows an example of the hardware constitutions of the degradation detection apparatus which concerns on embodiment. It is a block diagram showing an example of functional composition of a deterioration detecting device concerning an embodiment. FIG. 2 is a schematic diagram showing an example of the overall configuration when measuring AC impedance of a solar cell module with the degradation detection device according to the embodiment; 1 is a side cross-sectional view showing an example of the structure of a solar cell module according to an embodiment; FIG. It is a schematic diagram which shows an example of a structure of the measurement information database which concerns on embodiment. FIG. 10 is a front view showing an example of a detection state of the occurrence of the PID phenomenon by conventional measurement of EL light emission of a solar cell module that intentionally causes the PID phenomenon. 4 is a graph showing an example of transition of an IV curve as the PID phenomenon progresses, obtained by dark IV measurement on a solar cell module that intentionally causes the PID phenomenon. FIG. 10 is a graph showing an example of transition of a Nyquist diagram accompanying progress of the PID phenomenon, obtained by AC impedance measurement of a solar cell module that intentionally causes the PID phenomenon. FIG. 9 is a graph showing an example of a more detailed transition of the Nyquist diagram shown in FIG. 8; It is a circuit diagram which shows an example of an alternating current circuit model. 5 is a graph showing an example of temporal transition of resistance values of respective parts of an AC circuit model obtained using AC impedance; 6 is a flowchart showing an example of the flow of deterioration detection processing according to the embodiment; It is a front view which shows an example of a structure of the deterioration presentation screen which concerns on embodiment.

Embodiments for carrying out the present invention will be described in detail below with reference to the drawings. Here, a case where the present invention is applied to an information processing apparatus configured by a general-purpose personal computer, server computer, or the like will be described.

First, the configuration of a deterioration detection device 10 according to this embodiment will be described with reference to FIGS. 1 and 2. FIG. FIG. 1 is a block diagram showing an example of the hardware configuration of a deterioration detection device 10 according to this embodiment. Also, FIG. 2 is a block diagram showing an example of the functional configuration of the deterioration detection device 10 according to this embodiment.

As shown in FIG. 1, the deterioration detection device 10 according to the present embodiment includes a CPU (Central Processing Unit) 11, a memory 12 as a temporary storage area, a nonvolatile storage unit 13, an input unit 14 such as a keyboard and a mouse, A display unit 15 such as a liquid crystal display, a medium read/write device (R/W) 16 and a communication interface (I/F) unit 18 are provided. CPU 11 , memory 12 , storage unit 13 , input unit 14 , display unit 15 , medium read/write device 16 and communication I/F unit 18 are connected to each other via bus B. The medium read/write device 16 reads information written in the recording medium 17 and writes information to the recording medium 17 .

The storage unit 13 is implemented by a HDD (Hard Disk Drive), SSD (Solid State Drive), flash memory, or the like. A deterioration detection program 13A is stored in the storage unit 13 as a storage medium. The deterioration detection program 13A is stored in the storage unit 13 when the recording medium 17 in which the deterioration detection program 13A is written is set in the medium reading/writing device 16, and the medium reading/writing device 16 reads out the deterioration detection program 13A from the recording medium 17. It is stored (installed). The CPU 11 reads out the deterioration detection program 13A from the storage unit 13, develops it in the memory 12, and sequentially executes the processes of the deterioration detection program 13A.

The storage unit 13 also stores a measurement information database 13B. Details of the measurement information database 13B will be described later.

On the other hand, as shown in FIG. 1, the communication I/F unit 18 of the deterioration detection device 10 according to this embodiment is connected to a frequency characteristic analyzer 30 for measuring the AC impedance of the solar cell module. Therefore, the CPU 11 can acquire information indicating the measurement result by the frequency characteristic analyzer 30 via the communication I/F section 18 . Details of the frequency characteristic analyzer 30 will be described later.

Next, with reference to FIG. 2, the functional configuration of the deterioration detection device 10 according to this embodiment will be described.

As shown in FIG. 2, the deterioration detection device 10 according to this embodiment includes an acquisition unit 11A, a detection unit 11B, and a presentation unit 11C. By executing the deterioration detection program 13A, the CPU 11 of the deterioration detection device 10 functions as an acquisition unit 11A, a detection unit 11B, and a presentation unit 11C.

Acquisition unit 11A according to the present embodiment acquires an AC circuit model of a solar cell module that can reproduce a Nyquist diagram obtained from measurement results of AC impedance for the solar cell module and that has parallel resistance.

Further, the detection unit 11B according to the present embodiment detects occurrence of the PID phenomenon from the state of decrease in the resistance value of the parallel resistor in the AC circuit model acquired by the acquisition unit 11A. Note that the detection unit 11B according to the present embodiment detects that the PID phenomenon has occurred when the difference between the resistance value and the initial value is equal to or greater than a predetermined threshold value. is not limited to For example, the detection unit 11B may detect that the PID phenomenon has occurred when the resistance value is equal to or less than a predetermined threshold value.

Then, the presentation unit 11C according to the present embodiment presents the detection result by the detection unit 11B. In addition, in the present embodiment, a case where the presentation unit 11C presents the detection result by the detection unit 11B by display on the display unit 15 will be described, but the present invention is not limited to this. For example, the detection result may be presented in the form of sound produced by a sound generation device such as a speaker, or the detection result may be presented in the form of printing by an image forming device such as a printer.

Next, with reference to FIG. 3, the configuration for measuring the AC impedance of the solar cell module using the frequency characteristic analyzer 30 by the degradation detection device 10 according to the present embodiment will be described. FIG. 3 is a schematic diagram showing an example of the overall configuration when measuring the AC impedance of a solar cell module with the degradation detection device 10 according to this embodiment.

As shown in FIG. 3, in the present embodiment, a frequency characteristic analyzer 30 and a bipolar power supply 40, which are respectively connected to the solar cell module 20 whose AC impedance is to be measured, are used to measure the temperature of the solar cell module 20. Measure AC impedance. A frequency characteristic analyzer is a device that applies a sine wave signal to an object to be measured and obtains its frequency response, and is also called an FRA (Frequency Response Analyzer). Also, a bipolar power supply is a power supply that can operate in the entire region of one to four quadrants.

As shown in FIG. 3, in this embodiment, the solar cell module 20 and the bipolar power supply 40 are connected with one connection line via a shunt resistor Rsh and the other connection line directly. An output terminal for outputting the sine wave signal Vsig of the frequency characteristic analyzer 30 is connected to an input terminal of the bipolar power supply 40, and the frequency characteristic analyzer 30 outputs an output signal supplied from the bipolar power supply 40 to the solar cell module 20. to control (alternating current).

An input terminal for AC voltage measurement of the frequency characteristic analyzer 30 is connected to two connection lines between the solar cell module 20 and the bipolar power supply 40, and is connected to an input terminal for AC current measurement of the frequency characteristic analyzer 30. The terminals are connected across the shunt resistor Rsh. Therefore, under its own control, the frequency characteristic analyzer 30 uses the various frequencies of the alternating current input from the bipolar power supply 40 to the solar cell module 20 and the input alternating voltage and alternating current to analyze the solar cell The AC impedance of module 20 can be measured. Since the method for measuring the AC impedance is conventionally known, further explanation will be omitted.

On the other hand, as described above, the frequency characteristic analyzer 30 is connected to the deterioration detection device 10, and the deterioration detection device 10 controls the operation of the frequency characteristic analyzer 30 and measures the Information indicating the AC impedance of the solar cell module 20 (hereinafter referred to as "AC impedance information") can be received.

Next, the structure of the solar cell module 20 according to this embodiment will be described with reference to FIG. FIG. 4 is a side sectional view showing an example of the structure of the solar cell module 20 according to this embodiment.

As shown in FIG. 4 , in a solar cell module 20 according to this embodiment, a plurality of solar cells 21 are arranged in a matrix when viewed from above, and the solar cells 21 are connected to each other by metal conductors 22 . . Moreover, the solar battery cell 21 and the metal conductor 22 are sealed with a sealing material 23 that is a filler made of silicon resin or the like. The sealing material 23 is sandwiched by an aluminum frame 26 between a front cover 24 made of glass, film or the like and a back cover 25 made of a multi-layered film or the like.

However, the target solar cell module is not limited to the one shown in FIG. 4, and needless to say, a solar cell module having another structure can also be targeted.

Next, the measurement information database 13B according to this embodiment will be described with reference to FIG. FIG. 5 is a schematic diagram showing an example of the configuration of the measurement information database 13B according to this embodiment.

As shown in FIG. 5, the measurement information database 13B according to the present embodiment stores each piece of information on elapsed time and resistance value in association with each other.

The elapsed time is information indicating the elapsed time from the start of measurement of the AC impedance of the solar cell module 20, and the resistance value is the AC impedance of the solar cell module 20 measured at the corresponding elapsed time. It is information indicating the resistance value of the parallel resistor in the circuit model. Note that the resistance value is registered by a deterioration detection process (see also FIG. 12), which will be described later, so the details will be described later.

Next, the principle of detection of the PID phenomenon of the solar cell module by the degradation detection device 10 according to the present embodiment will be described with reference to FIGS. 6 to 11. FIG.

FIG. 6 shows a front view showing an example of the detection state of the occurrence of the PID phenomenon by conventional EL emission measurement for a solar cell module in which the PID phenomenon was intentionally caused by the PID accelerated test by the aluminum method. It is The right diagram in FIG. 6 shows the state of EL light emission in the solar cell module at the start of use (denoted as "new" in FIG. 6), and the left diagram shows the state of 30 hours after the start of use of the solar cell module. It shows the state of EL light emission at that time.

As shown in FIG. 6, no clear difference in brightness was observed when comparing the EL emission at the time of the start of use and the time after 30 hours from the start of use. Capturing such early-stage PID phenomena is extremely difficult.

Accordingly, the inventors of the present invention conducted the following studies with the aim of establishing a technique for detecting the occurrence of the PID phenomenon at the initial stage.

First, the inventors of the present invention performed dark IV measurement on a solar cell module in which a PID phenomenon was intentionally caused by a PID accelerated test using the aluminum method. FIG. 7 shows a graph showing an example of transition of the IV curve as the PID phenomenon progresses, based on the dark IV measurement. Note that FIG. 7 shows the measurement results at the start of use, after 2 hours, after 6 hours, after 19 hours, after 30 hours, and after 72 hours.

As shown in FIG. 7, the IV curve shifts from the right to the left as the elapsed time from the start of use increases, indicating that the PID phenomenon can be detected even by dark IV measurement. found. However, no clear change was observed after 2 hours or 6 hours from the start of use.

Next, the inventors of the present invention created a Nyquist diagram using measurement results of AC impedance for a solar cell module in which a PID phenomenon was intentionally caused by a PID accelerated test using the aluminum method. FIG. 8 shows a graph showing an example of the transition of the Nyquist diagram accompanying the progress of the PID phenomenon by measuring the AC impedance. Note that FIG. 8 shows the Nyquist diagram at the start of use (denoted as “new” in FIG. 8), 2 hours after the start of use, and 30 hours after the start of use. The Nyquist diagram is a diagram in which the real part of AC impedance is the value on the X-axis and the imaginary part is the value on the Y-axis.

As shown in FIG. 8, in this case, not only the Nyquist diagram after 30 hours from the start of use, but also the Nyquist diagram after 2 hours have clearly differed from the Nyquist diagram at the start of use. seen. FIG. 9 shows a graph showing an example of a more detailed transition of the Nyquist diagram shown in FIG. Also in the figure, a clear difference was seen from the Nyquist diagram at the beginning of use.

Therefore, the inventors of the present invention selected a circuit configuration that can reproduce the created Nyquist diagram and has a parallel resistance, performed fitting, and derived an AC circuit model by calculating the value of each element. . FIG. 10 shows a circuit diagram showing an example of the derived AC circuit model.

Then, the inventors of the present invention found that the resistance value (combined resistance value) of the parallel resistance Rp composed of the resistance Rd and the resistance Rsh in the created AC circuit model and the resistance value of the resistance Rpp with the passage of time The transition is shown graphically. An example of the graph is shown in FIG. Note that "+1000 V" and "-1000 V" in FIG. 11 represent voltages applied to the solar cell module when measuring AC impedance.

As shown in FIG. 11, it was found that the resistance value of the parallel resistor Rp significantly decreased after two hours from the start of use regardless of whether the voltage applied to the solar cell module was positive or negative.

As a result of the above study, the degradation detection device 10 according to the present embodiment detects the occurrence of the PID phenomenon in the solar cell module using the value of the parallel resistance Rp.

Next, operation of the deterioration detection device 10 according to the present embodiment will be described with reference to FIGS. 12 and 13. FIG. FIG. 12 is a flowchart showing an example of the flow of deterioration detection processing according to this embodiment.

When the user inputs an instruction to start execution of the deterioration detection program 13A through the input unit 14, the CPU 11 of the deterioration detection device 10 executes the deterioration detection program 13A, thereby performing the deterioration detection shown in FIG. Processing is performed. Prior to executing the deterioration detection process, the user constructs the configuration shown in FIG. 3 as an example for the solar cell module 20 to be detected for the PID phenomenon, and then inputs the above instruction.

At step 100 in FIG. 12 , the CPU 11 controls the frequency characteristic analyzer 30 to start measuring the AC impedance of the solar cell module 20 . By this control, the frequency characteristic analyzer 30 starts transmitting AC impedance information to the deterioration detection device 10 .

Therefore, at step 102, the CPU 11 uses the AC impedance information received from the frequency characteristic analyzer 30 to create an AC circuit model having the parallel resistance Rp as described above. At step 104, the CPU 11 calculates the resistance value of the parallel resistor Rp in the created AC circuit model.

At step 106, the CPU 11 stores (registers) the calculated resistance value of the parallel resistor Rp in the measurement information database 13B together with information indicating the elapsed time from the start of the deterioration detection process to this point. At step 108, the CPU 11 waits until a predetermined time (5 minutes in this embodiment) has passed.

At step 110, the CPU 11 determines whether or not the number of times the resistance value is registered in the measurement information database 13B by the immediately preceding step 106 from the start of this deterioration detection process is the second time or later, and a negative determination is made. If so, go to step 120 . Moreover, when the said determination becomes affirmative determination, it transfers to step 112. FIG.

At step 112, the CPU 11 calculates the difference D between the resistance value first registered in the measurement information database 13B and the resistance value registered in the measurement information database 13B by the process of step 106 immediately before. At step 114, the CPU 11 determines whether or not the calculated difference D is equal to or greater than a predetermined threshold value. transition to In the present embodiment, as the threshold value, a solar cell module of the same type as the solar cell module 20 is used as a value at which it can be considered that the PID phenomenon has occurred in the solar cell module 20 when the difference D is equal to or greater than the threshold value. Values obtained in advance by experiments, etc., are applied. However, it is not limited to this form, and for example, a form in which the user inputs the threshold in advance according to the detection accuracy of the occurrence of the PID phenomenon required for the deterioration detection device 10, the use of the deterioration detection device 10, etc. may be

At step 116, the CPU 11 controls the display unit 15 to display a degradation presentation screen configured in advance using the resistance value used when calculating the difference D, and at step 118, the CPU 11 waits until predetermined information is input.

FIG. 13 shows an example of a degradation presentation screen according to this embodiment. As shown in FIG. 13, on the deterioration presentation screen according to the present embodiment, a message indicating that the PID phenomenon may occur in the solar cell module 20 is displayed, and the display is used when calculating the difference D. Two types of resistance values are displayed. Therefore, by referring to the deterioration presentation screen, the user can grasp the possibility that the PID phenomenon is occurring in the solar cell module 20, and can also determine from the displayed resistance value the solar power at this time. The degree of deterioration of the battery module 20 and the like can be predicted.

As an example, when the deterioration presentation screen shown in FIG. Accordingly, step 118 makes an affirmative determination, and the process proceeds to step 122 .

On the other hand, in step 120, the CPU 11 determines whether or not the predetermined end timing has arrived. . In this embodiment, as the end timing, the timing when a time set in advance by the user (for example, two hours) has passed is applied, but it is needless to say that the end timing is not limited to this.

At step 122, the CPU 11 controls the frequency characteristic analyzer 30 to stop the measurement of the AC impedance, and then terminates this deterioration detection process.

As described above, according to the present embodiment, an AC circuit model of a solar cell module that can reproduce the Nyquist diagram obtained from the measurement result of the AC impedance of the solar cell module and that has a parallel resistance is obtained. Then, the occurrence of the PID phenomenon is detected from the decrease in the resistance value of the parallel resistor in the acquired AC circuit model. Therefore, the occurrence of the PID phenomenon in the solar cell module can be discovered earlier.

Further, according to the present embodiment, it is detected that the PID phenomenon has occurred when the difference between the resistance value and the initial value is greater than or equal to a predetermined threshold value. Therefore, it is possible to detect the occurrence of the PID phenomenon in the solar cell module with higher accuracy than the case where the occurrence of the PID phenomenon is detected when the resistance value itself becomes equal to or less than a predetermined threshold value. can be done.

Furthermore, according to this embodiment, the above detection result is presented. Therefore, it is possible to easily comprehend the detection result.

In the above-described embodiment, a case has been described in which the presence or absence of the PID phenomenon is detected using the amount of change (difference D) from the start of measurement of the resistance value of the parallel resistor Rp, but the present invention is not limited to this. For example, the rate of change of the resistance value of the parallel resistor Rp may be used to detect whether or not the PID phenomenon occurs. In this case, it may be detected that the PID phenomenon has occurred. In the form of using the resistance value of the parallel resistor Rp itself, it is possible to detect the occurrence of the PID phenomenon in the solar cell module more easily than in the case of detecting the occurrence of the PID phenomenon using the amount of change or rate of change. can be done.

Further, in the above embodiment, for example, the hardware structure of the processing unit that executes each process of the acquisition unit 11A, the detection unit 11B, and the presentation unit 11C includes various processors shown below. ) can be used. As described above, the various processors include a CPU, which is a general-purpose processor that executes software (programs) and functions as a processing unit, as well as FPGAs (Field-Programmable Gate Arrays), etc., which have circuit configurations after manufacturing. Programmable Logic Device (PLD), ASIC (Application Specific Integrated Circuit), etc. etc. are included.

The processing unit may be configured with one of these various processors, or a combination of two or more processors of the same type or different types (for example, a combination of multiple FPGAs or a combination of a CPU and an FPGA). may consist of Also, the processing unit may be configured with a single processor.

As an example of configuring the processing unit with one processor, first, one processor is configured by combining one or more CPUs and software, as typified by computers such as clients and servers. There is a form that functions as a processing unit. Secondly, there is a form of using a processor that implements the functions of the entire system including the processing section with a single IC (Integrated Circuit) chip, as typified by a System On Chip (SoC). In this way, the processing unit is configured using one or more of the above various processors as a hardware structure.

Furthermore, as the hardware structure of these various processors, more specifically, an electric circuit (circuitry) in which circuit elements such as semiconductor elements are combined can be used.

10 deterioration detection device 11 CPU
11A acquisition unit 11B detection unit 11C presentation unit 12 memory 13 storage unit 13A deterioration detection program 13B measurement information database 14 input unit 15 display unit 15C end button 16 medium read/write device 17 recording medium 18 communication I/F unit 20 solar cell module 21 sun Battery cell 22 Metal conductor 23 Sealing material 24 Front cover 25 Back cover 26 Aluminum frame 30 Frequency characteristic analyzer 40 Bipolar power supply

Claims (5)

an acquisition unit that acquires an AC circuit model of the solar cell module that is capable of reproducing a Nyquist diagram obtained from measurement results of AC impedance for the solar cell module and that has a parallel resistance;
A detection unit that detects the occurrence of a PID phenomenon from the state of the decrease in the resistance value of the parallel resistor in the AC circuit model acquired by the acquisition unit;
A deterioration detection device with The detection unit detects that the PID phenomenon has occurred when the resistance value is equal to or less than a predetermined threshold value.
The deterioration detection device according to claim 1. The detection unit detects that the PID phenomenon has occurred when the difference between the resistance value and the initial value is equal to or greater than a predetermined threshold value.
The deterioration detection device according to claim 1. a presentation unit that presents a detection result by the detection unit;
The deterioration detection device according to any one of claims 1 to 3, further comprising: Acquiring an AC circuit model of the solar cell module that can reproduce the Nyquist diagram obtained from the measurement result of the AC impedance for the solar cell module and has a parallel resistance,
Detecting the occurrence of the PID phenomenon from the state of the decrease in the resistance value of the parallel resistor in the acquired AC circuit model,
A deterioration detection program that causes a computer to execute processing.

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