JP2014228517A - Method for evaluating solar cell module and use of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and an apparatus for evaluating the performance of a solar cell module under light irradiation.SOLUTION: The performance of a solar cell module can be evaluated by analyzing the difference between an electroluminescent (EL) image when current is injected into a solar cell module and an image when no current is injected to detect weak EL even under light irradiation.

Description

  TECHNICAL FIELD The present invention relates to a solar cell module evaluation method and use thereof, and more particularly, to a solar cell module evaluation method and use thereof that can be performed under light irradiation (for example, outdoors under sunlight). .

  The use of solar energy is progressing in order to preserve the global environment, and the installation of solar cell modules in which a plurality of solar cell elements are connected to the roofs and walls of ordinary buildings and homes is in progress. However, solar cell modules made of Si (silicon) or the like have not been spread as expected because of high cost.

  One of the reasons for the high cost of the solar cell module is the presence of an inspection process for output characteristics when the solar cell module is irradiated with sunlight, that is, a process for evaluating the quality of the solar cell module. The process of evaluating the output characteristics of the solar cell module is an important measurement item performed in the inspection after manufacturing the solar cell module and in the research and development of the solar cell module.

  So far, the present inventors have injected a current in the forward direction into a silicon-type solar cell module installed in a dark room to generate electroluminescence (EL), and analyze the light emission state to thereby obtain the solar cell module. Has developed a method for evaluating the performance (see, for example, Patent Document 1).

  Further, unlike the above technique, a method for evaluating the performance of the solar cell module without injecting current into the solar cell module has been developed. For example, a technique for evaluating the performance of a solar cell module by modulating the operating conditions with a device such as an inverter and detecting the light emission state of the solar cell module under sunlight with respect to the solar cell module has been reported. Yes. In addition, the light emission state obtained by this technique has the fault that it changes depending on the irradiation amount of sunlight (nonpatent literature 1).

International Publication No. 2006/059615

L. Stoicescu, M. Reuter, and J. H. Werner, Daylight Luminescence for Photovoltaic System Testing, in Proc. 22nd International Photovoltaic Science and Engineering Conference (Hangzhou, China, 2012)

  All of the above technologies are excellent, but this is not enough. For example, in the technique described in Patent Document 1, it is necessary to eliminate the influence of disturbance light in order to improve evaluation accuracy. Moreover, although the technique described in the nonpatent literature 1 presupposes irradiation of sunlight, since intensity | strength changes with sunlight, it is difficult to perform quantitative evaluation.

  For this reason, development of the new technique for evaluating the performance of a solar cell module is strongly calculated | required.

  In order to solve the above-mentioned problems, the present inventors have intensively studied. As a result, even under strong light irradiation such as sunlight, no special equipment such as a dark room is required, and the solar cell module is quantitatively obtained. We have succeeded in developing a new technology that can be used for performance evaluation. Specifically, by analyzing the difference between the EL image when current is injected into the solar cell module and the image without current injection, weak EL is detected even under light irradiation, The inventors have found a new finding that the performance of the solar cell module can be evaluated, and have completed the present invention. That is, the present invention includes the following inventions.

  (1) A method for evaluating a solar cell module under light irradiation, in which a current is injected into the solar cell module in a forward direction, and current is injected in the first current injection step A first image acquisition step of acquiring a first image of the solar cell module in a state of being in operation, and a first step of injecting a smaller current than the first current injection step in the forward direction with respect to the solar cell module 2 current injection step, a second image acquisition step of acquiring a second image of the solar cell module in a state where current is injected in the second current injection step, the first image and the second An image forming step of analyzing a difference between the second image and obtaining a third image representing a light emission state caused by current injection in the first current injection step to the solar cell module; Based on image The evaluation method of a solar cell module comprising: a determination step of determining performance of the solar cell module.

  (2) The method for evaluating a solar cell module according to (2), wherein in the first current injection step, a current exceeding a photovoltaic power is applied to the solar cell module to inject current.

  (3) The solar cell according to (1) or (2), wherein in the second current injection step, current is injected by applying a voltage equal to or higher than the photovoltaic power to the solar cell module. Module evaluation method.

  (4) The method for evaluating a solar cell module according to (1) or (2), wherein in the second current injection step, no current is injected into the solar cell module.

  (5) The image forming step performs the first image acquisition step and the second image acquisition step a plurality of times, and performs an averaging process on the obtained first and second images. The evaluation method of the solar cell module according to any one of (1) to (4), including a step of acquiring a third image from the difference.

  (6) In the image forming process, the first image acquisition process and the second image acquisition process are alternately performed a plurality of times, and the image obtained from each first image acquisition process and the second image acquisition process are performed. The method for evaluating a solar cell module according to any one of (1) to (5), including a step of obtaining a sum of differences from the image obtained from the step.

  (7) The image forming step includes steps (1) to (4) for removing a light emission caused by a photovoltaic force caused by light irradiated on the solar cell module by synchronous detection and acquiring a third image. ) The solar cell module evaluation method according to any one of the above.

  (8) A light emission detection step of detecting light in a first region having a wavelength of 800 nm to 1300 nm and light in a second region having a wavelength of 1400 nm to 1800 nm among the light emission generated in the third image, In the determination step, the intrinsic defect and the extrinsic defect are separated using the light emission intensity of the first region detected in the light emission detection step and the light emission intensity of the second region as an index (1) to The evaluation method of the solar cell module according to any one of (7).

  (9) The solar cell module evaluation method according to (8), wherein in the light emission detection step, detection is performed using a band-pass filter that selectively transmits 1150 nm light.

  (10) A solar cell module evaluation apparatus under light irradiation, wherein the first current injection means injects a current in the forward direction with respect to the solar cell module, and the forward direction with respect to the solar cell module. Second current injection means for injecting a current smaller than the current injected by the first current injection means, and an image of the solar cell module in a state where current is injected by the first current injection means The image acquisition means for acquiring the first image and the second image in a state where current is injected by the second current injection means, and the difference between the first image and the second image Analyzing and obtaining an image forming means for obtaining a third image representing a light emission state caused by current injection by the first current injection means to the solar cell module, and based on the third image, the sun Battery module Evaluation apparatus of a solar cell module and a determining means for determining performance in.

  (11) The first current injection unit is configured to inject a current by applying a voltage exceeding the photovoltaic force to the solar cell module when the image acquisition unit acquires the first image. The solar cell module evaluation apparatus according to (10).

  (12) The second current injection unit applies a voltage equal to or higher than the photovoltaic power to the solar cell module when the image acquisition unit acquires the second image. The solar cell module evaluation apparatus according to (10) or (11), which is to be injected.

  (13) The second current injection unit does not inject current into the solar cell module when the image acquisition unit acquires the second image. Solar cell module evaluation device.

  (14) The image forming means averages a plurality of first images and second images, and obtains the third image from the difference between the images (10) to (13). The evaluation apparatus of the solar cell module in any one.

  (15) The image forming unit alternately acquires the first image and the second image a plurality of times, and obtains the sum of the differences between the first image and the second image at each time. The solar cell module evaluation apparatus according to any one of (10) to (14).

  (16) Any of (10) to (15), in which the image forming unit acquires an image by removing light emission due to the photovoltaic force caused by light irradiated on the solar cell module by synchronous detection. An evaluation apparatus for a solar cell module according to claim 1.

  (17) It further includes emission detection means for detecting light in a first region having a wavelength of 800 nm to 1300 nm and light in a second region having a wavelength of 1400 nm to 1800 nm among the light emission generated in the third image, In the determination means, the intrinsic defect and the extrinsic defect are separated using the light emission intensity of the first region detected by the light emission detection means and the light emission intensity of the second region as an index (10) to (16) The solar cell module evaluation device according to any one of (16).

  (18) The evaluation apparatus for a solar cell module according to (17), wherein the light emission detection means detects using a band-pass filter that selectively transmits 1150 nm light.

  (19) The solar cell module evaluation apparatus according to any one of (10) to (18), wherein the evaluation process for evaluating the performance of the solar cell module installed in the structure and the replacement instruction apparatus are the above A method for instructing a replacement operator of the solar cell module to replace the defective portion of the solar cell module via a communication network based on the inspection result in the evaluation step.

  (20) Based on the evaluation device of the solar cell module according to any one of (10) to (18) and the evaluation result of the evaluation device, the solar cell module is exchanged via a communication network. A solar cell module maintenance system comprising: a replacement instruction device for instructing a replacement operator of

  (21) A method for producing a solar cell module, comprising the method for evaluating a solar cell module according to any one of (1) to (9) as a step.

  According to the solar cell module evaluation method or evaluation apparatus according to the present invention, it is possible to evaluate the performance of the solar cell module without requiring special equipment such as a dark room even under irradiation of light such as sunlight. Play. Further, according to the present invention, it is possible to quantitatively evaluate the performance of the solar cell module. For this reason, for example, a mega solar system comprising a solar cell module already installed outdoors or a large number of solar cell modules can be easily maintained even under sunlight.

It is a figure which shows typically an example of the evaluation apparatus of the solar cell module which concerns on embodiment of this invention. It is a figure which shows the functional block diagram which showed typically an example of the evaluation apparatus of the solar cell module which concerns on embodiment of this invention. It is a figure showing the functional block diagram showing typically an example of the maintenance system of the solar cell module concerning the embodiment of the present invention. It is a figure which shows an example of the flow of the maintenance system of the solar cell module which concerns on embodiment of this invention. It is a figure which shows the image which image | photographed the mode of the solar cell module in Example 1. FIG. It is a figure which shows the image which image | photographed the mode of the highly efficient single-crystal silicon element in Example 2. FIG. It is a figure which shows the image which image | photographed the mode of the highly efficient single-crystal silicon element in Example 3. FIG. It is a figure which shows the image which image | photographed the mode of the highly efficient single-crystal silicon element in Example 4. FIG. It is a figure which shows the image which image | photographed the mode of the highly efficient single-crystal silicon element in Example 5. FIG.

  An embodiment of the present invention will be described in detail below. In addition, all the academic literatures and patent literatures described in this specification are incorporated by reference in this specification. Unless otherwise specified in this specification, “A to B” representing a numerical range means “A or more (including A and greater than A) and B or less (including B and less than B)”.

<1. Evaluation Method for Solar Cell Module>
The solar cell module evaluation method of the present invention is a solar cell module evaluation method under light irradiation, and includes a first current injection step of injecting a current in the forward direction to the solar cell module, and the first A first image acquisition step of acquiring a first image of the solar cell module in a state of injecting a current in the current injection step, and the first current injection step in the forward direction with respect to the solar cell module. A second current injection step of injecting a smaller current, and a second image acquisition step of acquiring a second image of the solar cell module in a state where current is injected in the second current injection step, The image which analyzes the difference of the said 1st image and a 2nd image, and acquires the 3rd image showing the light emission state resulting from the current injection in the 1st current injection process to the said solar cell module And forming step, based on the third image may include at a determination step of determining performance of the solar cell module.

  In the present specification, “evaluating a solar cell module under light irradiation” may be anything as long as the solar cell module is evaluated under light irradiation, that is, in the presence of light, and other configurations are not limited. For example, evaluate a solar cell module under the influence of sunlight or certain disturbance light such as outdoors, or evaluate the performance of a solar cell module in the presence of a light source such as an incandescent bulb or a solar simulator indoors. Is meant to encompass. That is, the evaluation method according to the present invention is characterized in that a light-shielding space such as a dark room is not required when evaluating a solar cell module. In addition, the evaluation method according to the present invention has a feature that enables evaluation of the solar cell module even in a situation where sunlight is weak or does not exist, for example, cloudy weather, twilight, and nighttime.

  Evaluation or determination of “performance of the solar cell module” in the present specification means evaluation of performance regarding the photoconductive effect and / or the photovoltaic effect in the solar cell module.

  Here, the term “solar cell module” refers to a configuration in which solar cell elements, which are the minimum structural units that receive light and generate current, are connected by the photoconductive effect and / or the photovoltaic effect. . For example, a solar cell element having a size of about 0.5 m × 0.5 m to 1 m × 1 m, in which about 10 to 50 solar cell elements having a size of 10 cm × 10 cm to 15 cm × 15 cm are connected. In this specification, the “solar cell module” includes “solar cell panel” that is an assembly of modules, and “mega solar system” that is an assembly of the “solar cell panel”, A solar cell element is included. Specific examples of the solar cell module include a solar cell module made of a polycrystalline silicon semiconductor, high-efficiency single crystal silicon, amorphous silicon, and a compound thin film solar cell.

  Moreover, the evaluation method of the solar cell module of the present invention includes a light in a first region having a wavelength of 800 nm to 1300 nm and a light in a second region having a wavelength of 1400 nm to 1800 nm among the light emission generated in the third image. A light emission detection step for detecting, and in the determination step, the intrinsic defect and the external cause are detected using the light emission intensity of the first region and the light emission intensity of the second region detected in the light emission detection step as indices. Can be discriminated from mechanical defects.

  In the present specification, the “endogenous defect” means a defect caused by an internal factor. “Intrinsic defects” are defects caused by the physical properties of the solar cell module such as crystal defects, crystal dislocations, and crystal grain boundaries, and affect the function of the solar cell module. Does not significantly affect reliability.

  In the present specification, “exogenous defect” means a defect caused by an external factor. “Exogenous defects” are mechanical defects of the solar cell module, such as substrate cracks (micro cracks, etc.), electrode breakage, electrode contact failure, etc., which produce solar cell module reliability and solar cell modules This adversely affects the production yield at the time, and becomes a decisive factor for efficiently mass-producing highly reliable solar cell modules.

  The decrease in the performance of the solar cell module is generally due to defects caused by internal factors (internal defects) and defects caused by external factors (external defects). In the solar cell module evaluation method described above, these defects are determined to indicate that the performance of the solar cell module is degraded.

  Hereinafter, each process of the evaluation method of the solar cell module according to the present invention will be described in detail. In addition, specific processes other than these processes, materials, conditions, devices and apparatuses to be used are not particularly limited, and various methods can be suitably used.

<1-1. First Current Injection Step>
The first current injection step may be a step of injecting a current in the forward direction with respect to the solar cell module. The current to be injected may be a direct current or a pulse current. Hereinafter, an evaluation method in the case of injecting a direct current will be described.

  In the first current injection step, “injecting a current in the forward direction” means applying a bias to the so-called solar cell module in order to inject a current in the forward direction. By applying an external voltage having a positive (+) polarity to the p-type region side and a negative (-) polarity to the n-type region side of the pn junction of the solar cell module, a current is injected in the forward direction. Thereby, the light by electroluminescence is radiated | emitted from a solar cell module.

The magnitude of the current to be injected in this step is not particularly limited, but the current density of the injected current is at least higher than the second current injection step described later, for example, 5 to 120 mA / cm ^2. preferably, more preferably 5~80mA / cm ^2, further preferably 5 to 40 mA / cm ^2. When the solar cell module to be evaluated is single crystal silicon, the current density is about 1/4 to 4 times the current density (for example, 40 mA / cm ² ) of the current actually generated by photoelectric conversion of the solar cell element. It is preferable to inject current. Within such a range, an electroluminescence image related to the performance evaluation of the solar cell module can be acquired.

  As a device for injecting current into the solar cell module, various power sources and the like can be suitably used, and the device is not particularly limited. In the present specification, the “power source” is not particularly limited as long as it can inject current into the solar cell module and cause the solar cell module to emit light (electroluminescence). Can be used. For example, a power source for injecting a direct current and a power source for injecting a pulse current may be used for the solar cell module, or a sine wave using an inverter may be appropriately used. As the “power source” in the present specification, various currents other than those described above, such as a triangular wave using an inverter and a modified sine wave obtained by slightly deforming a sine wave, can be used. In addition, when acquiring the 3rd image mentioned later by synchronous detection, in order to remove suitably the light emission by the photoelectromotive force resulting from the light (what is called background light and disturbance light) irradiated to a solar cell module, a pulse current is used. It is preferable to use a power source to be injected or a sine wave using an inverter.

  Moreover, in the solar cell module under light irradiation, photovoltaic power is generated by photoelectric conversion. For this reason, in order to inject current in the forward direction with respect to the solar cell module, it is preferable that the current is injected by applying a voltage exceeding the photovoltaic power generated by the solar cell module.

<1-2. First image acquisition step>
The first image acquisition step may be a step of acquiring a first image of the solar cell module in a state where current is injected in the first current injection step, and a specific method thereof is particularly It is not limited and various techniques can be used suitably.

  The “first image” is an image of a solar cell module that emits light by injecting current in the first current injection step, and can be rephrased as an image showing the distribution of light emission characteristics of the solar cell module. “Luminescence characteristics” includes emission intensity and spectral characteristics (emission intensity of each spectrum).

  In this step, various image acquisition means (devices) that can detect light from the solar cell module can be used, and the specific configuration and the like are not particularly limited.

  As the image acquisition device, a photodetector such as a CCD camera and an image intensifier can be used. As an image acquisition apparatus, for example, an InGaAs camera (manufactured by Xenics, product number XEVA-1.7 series), a CCD camera (manufactured by Hamamatsu Photonics, product number C8250-20), and an Si CCD camera (manufactured by Hamamatsu Photonics, product number C9299). -02) and the like. Examples of the image intensifier include an image intensifier (part number V8071U-76) manufactured by Hamamatsu Photonics Co., Ltd., which can detect light in a wavelength region of 360 nm to 1100 nm. When light is detected using such a CCD camera and a photodetector such as an image intensifier, the light emission state in the solar cell module can be observed as an image. That is, the in-plane distribution of light emission in the solar cell module can be collectively measured two-dimensionally. The solar cell module can be easily and quickly evaluated.

<1-3. Second Current Injection Step>
The second current injection step may be a step of injecting a smaller current than the first current injection step in the forward direction with respect to the solar cell module. The current to be injected may be a direct current or a pulse current.

  “Injecting a current smaller than that of the first current injection step” may be a step of injecting a smaller current than the current injected in the first current injection step. There is no particular limitation on the length. For example, a current corresponding to that current is injected by applying a voltage equal to or higher than the photovoltaic power generated in the solar cell module under light irradiation, or no current is injected. May be.

  In this step, since the current injected into the solar cell module is smaller than the current injected in the first current injection step, the light emission state of the solar cell module and the second current injection step in the first current injection step A difference can be caused between the light emitting state of the solar cell module due to the above. That is, the emission intensity of the solar cell module in the second current injection step is weaker than the emission intensity of the solar cell module in the first current injection step.

  When current is injected by applying a voltage equal to or higher than the photovoltaic power generated in the solar cell module under light irradiation, the voltage applied artificially for current injection and the light generated from the solar cell module Since the electromotive forces cancel each other, substantially no current flows in the solar cell module itself, and the solar cell module does not emit light. Similarly, when no current is injected into the solar cell module, the solar cell module does not emit light. Similarly, when no current is injected into the solar cell module, the solar cell module does not emit light due to the current injection.

The magnitude of the current to be injected in this step is not particularly limited, smaller current density than at least the first current injection process, for example, preferably less than ^{5~120mA / cm 2, 5~80mA / cm} 2 It is more preferably smaller, and further preferably smaller than 5 to 40 mA / cm ² . At that time, when the difference in current density between the first current injection step and the second current injection step is larger, the intensity of the electroluminescence emission intensity of the solar cell module is detected in the <1-7> column described later. Cheap.

  About the other structure, description of the <1-1> column mentioned above is used.

<1-4. Second image acquisition step>
The second image acquisition step may be a step of acquiring a second image of the solar cell module in a state where current is injected in the second current injection step. It is not particularly limited.

  In the second current injection step, the current injected into the solar cell module is smaller than the current injected in the first current injection step, as described above. The “image” is an image whose emission intensity is weaker than that of the first image. In addition, there is no light emission when current is injected by applying a voltage equal to or higher than the photovoltaic power generated in the solar cell module under light irradiation, or when current is not injected into the solar cell module. It is an image of a solar cell module.

  Various image acquisition devices can be used for image acquisition, and the specific configuration and the like are not particularly limited. A specific image acquisition apparatus is the same as that described in <1-2> above, and is omitted here.

<1-5. Image forming process>
In the image forming step, a difference between the first image and the second image is analyzed, and a third light emission state caused by current injection in the first current injection step to the solar cell module is expressed. The specific method is not particularly limited as long as it is a process for obtaining the image.

  In this step, by analyzing the difference between the first image and the second image, light other than the electroluminescence of the solar cell module, that is, background light, disturbance light, etc. (effects) under light irradiation is excluded. And only the electroluminescence of the solar cell module resulting from the first current injection step can be analyzed.

  “Analyzing the difference between the first image and the second image” means, for example, the light emission intensity of the solar cell module obtained from the second image from the light emission intensity of the solar cell module obtained from the first image. Including subtracting. In this case, the “third image” refers to the emission intensity obtained by subtracting the emission intensity of the solar cell module obtained from the second image from the emission intensity of the solar cell module obtained from the first image. It is a representation.

  In the present step, when the difference between the first image and the second image is difficult to obtain due to the presence of background light, disturbance light, or the like, or in order to obtain a more accurate result, the first image Even if the acquisition process and the second image acquisition process are performed a plurality of times, and the obtained first and second images are averaged, the third image is acquired from the difference. Good. “Averaging processing” means taking the average value of the light emission intensities of a plurality of first images and second images. In this step, the first image acquisition step and the second image acquisition step are alternately performed a plurality of times, and the image obtained from each first image acquisition step and the second image acquisition step are obtained. A sum of differences from the obtained image may be obtained. Thereby, a high quality 3rd image with a high SN ratio (signal noise ratio) is acquirable.

  Further, in this step, the third image may be acquired by removing light emission due to the photovoltaic force caused by light (so-called background light or disturbance light) irradiated on the solar cell module by synchronous detection. A high-quality third image can also be acquired by removing light emission due to the photovoltaic force caused by the light applied to the solar cell module by synchronous detection.

  Various techniques are known for the averaging process, the process of obtaining the sum of differences, or the synchronous detection process at the time of filing of the present application, and these can be suitably used.

<1-6. Luminescence detection process>
The light emission detection step may be a step for detecting light in the first region having a wavelength of 800 nm to 1300 nm and light in the second region having a wavelength of 1400 nm to 1800 nm among the light emission generated in the third image. The specific method thereof is not particularly limited, and a conventionally known technique can be suitably used.

  In this step, conventionally known light detection means (apparatus) that can detect light (for example, light having a wavelength in the vicinity of 800 nm to 1800 nm) generated in the third image can be used. It is not limited.

  As the light detection device, a CCD camera and a light detector such as an image intensifier similar to the image acquisition device described in the section <1-2> can be used. A specific photodetection device is the same as that in <1-2> described above, and is omitted here.

  In this step, it is preferable to detect the light in the first region and the light in the second region using a single light detection device. This eliminates the need for replacement of the light detection device and the accompanying position adjustment, so that this step can be performed more easily. In this case, for example, an InGaAs camera or a CCD camera can be used. In addition, you may detect the light of a 1st area | region and the light of a 2nd area | region using a separate photodetector. In this case, for example, a Si CCD camera, an InGaAs camera, and a CCD camera can be used in combination, and an image intensifier (product number V8071U-76, manufactured by Hamamatsu Photonics Co., Ltd.), an InGaAs camera, and a CCD camera are used in combination. You can also. Furthermore, these three types of photodetectors can be combined.

  As described above, when one photodetection device such as an InGaAs camera or a CCD camera detects the wavelength region of 800 nm to 1800 nm, that is, the light in the first region and the light in the second region at the same time, these lights are used. It is preferable to use a band-pass filter that selectively passes each. Thereby, the light of the first region and the light of the second region can be efficiently detected and observed separately. That is, in this step, the light detection device capable of simultaneously detecting the light in the first region and the light in the second region and either the light in the first region or the light in the second region are selectively selected. It can be said that detection is preferably performed using a band-pass filter that passes through.

  Each bandpass filter may be disposed between the solar cell module and the photodetection device so that light generated from the solar cell module passes through the bandpass filter before reaching the photodetection device. You may equip with the lens part of a detection apparatus. An example of a bandpass filter that selectively transmits light in the first region is BROAD BANDPASS FILTER (manufactured by SPECTROGON, part number BBP-0910-1170C), and selectively transmits light in the second region. Examples of the bandpass filter include BROAD BANDPASS FILTER (product number BBP-1350-1600C, manufactured by SPECTROGON).

  Thus, since the wavelength region and emission intensity of the light generated from the third image differ depending on the type of defect, the light of each wavelength is detected using a different bandpass filter having a different wavelength pass band, and the emission intensity. By performing a comparative analysis based on the above, it is possible to easily and quickly evaluate the defect.

  Note that among the light emission generated from the third image, light in the first region is light having a wavelength of 800 nm to 1300 nm, preferably 900 nm to 1250 nm, and more preferably 1100 nm to 1200 nm. In addition, among the light emission generated from the third image, light in the second region is light having a wavelength of 1400 nm to 1800 nm, preferably 1500 nm to 1700 nm, and more preferably 1550 nm to 1650 nm. The light peak in the first region has a wavelength of 1150 nm, and the light peak in the second region has a wavelength of 1600 nm.

  Since the peak of light in the first region is 1150 nm, it is preferable to use a 1150 nm bandpass filter.

<1-7. Judgment process>
The determination step is a step of determining the performance of the solar cell module based on the third image.

  “Determining based on the third image” means determining whether the performance of the solar cell module is good or not, using the intensity of electroluminescence emission of the solar cell module obtained from the third image as an index. To do. When the emission intensity in the third image is greater than a predetermined value, the performance of the solar cell module is determined to be good, and when the emission intensity is less than the predetermined value, the performance of the solar cell module is determined to be poor. .

  Here, the “predetermined value” can be appropriately set and is not particularly limited. For example, when it falls below this value, it may be a so-called threshold value that a sufficient photoelectric conversion performance cannot be obtained, or a non-defective solar cell module or a defective solar cell produced in a manufacturing factory. An average value of the light emission characteristics of the module may be measured in advance, and this value may be a predetermined value. That is, in this step, it is only necessary to compare the obtained emission intensity with a preset reference value, and various techniques can be suitably used as specific methods.

  Further, in this step, the intrinsic defect and the extrinsic defect can be distinguished using the light emission intensity of the first region detected in the light emission detection step and the light emission intensity of the second region as an index. It is preferable that

  In this case, in this step, for example, the light emission intensity of the first region and the light emission intensity of the second region are respectively compared with the first threshold value and the second threshold value, and the results are compared. Process. The comparison method is not particularly limited.

  As a method for comparing with the first threshold value and the second threshold value, for example, there is a method of digitizing the emission intensity in the third image detected by the light detection device, and comparing the result. .

  In this step, for example, (i) it is determined that there is a defect when the emission intensity of the first region is equal to or lower than the first threshold, and (ii) When the emission intensity of the area 2 is equal to or higher than the second threshold, it may be determined that the part is an intrinsic defect, and other parts may be determined as an extrinsic defect. According to this, first, after detecting a site where a defect exists based on the light emission intensity of the first region, the defect detected based on the light emission intensity of the second region is an intrinsic defect, or is extrinsic. Whether it is a defect can be sorted out.

  Further, in this step, (iii) a region where the emission intensity of the first region is not more than the first threshold and the emission intensity of the second region is not less than the second threshold is an intrinsic defect. And (iv) determining that the part where the light emission intensity of the first region is equal to or lower than the first threshold and the light emission intensity of the second region is less than the second threshold is an extrinsic defect. Also good. The order of the (iii) process and the (iv) process is not particularly limited, and after the (iii) process is performed, the (iv) process may be performed or vice versa. Further, the step (iii) and the step (iv) may be performed in parallel. In particular, by performing the step (iii) and the step (iv) in parallel, it is possible to evaluate the defects of the solar cell module more quickly than when the steps (i) and (ii) are performed. .

  In addition, the “first threshold value” and the “second threshold value” in the steps (i) to (iv) may be different or the same. For example, the “first threshold value” in step (i) is the same as the “first threshold value” for comparing the emission intensity of the first region in steps (iii) and (iv), and (ii) step And the “second threshold” for comparing the light emission intensity of the second region in the steps (iii) and (iv).

  In addition, the “first threshold value” and the “second threshold value” are values for determining defects, and can be set as appropriate, considering the performance of the desired solar cell element, the yield, and the like. The user can set it arbitrarily. When the first threshold value is set low, the yield can be improved, and when the first threshold value is set high, a solar cell element with better quality can be obtained. When the second threshold value is set high, the yield can be improved, and when the second threshold value is set low, a solar cell element with better quality can be obtained. For example, a site where an intrinsic defect and / or an extrinsic defect exist in a solar cell element is identified in advance using a conventionally known method, and the light emission intensity or the first region of the first region from these sites is identified. The threshold value may be set by digitizing the light emission intensity of the region 2. This is a value as a so-called control. Such a threshold value may be set based on the solar cell to be evaluated, or may be set in advance based on another solar cell.

  For example, the “first threshold value” is a value of the light emission intensity of the first region generated from a normal part of the solar cell element by injecting a current into the solar cell element in the above-described current injection step. 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20% of the light emission intensity of the first region generated from the normal part of the solar cell element. Or a value of 10%. If the first threshold value is set close to the emission intensity generated from the normal part of the solar cell element, a minor defect can be detected. On the other hand, as the first threshold value is set lower than the emission intensity generated from the normal part of the solar cell element, the more severe defects can be detected. The “normal part” is intended to be a part of the solar cell in which neither an intrinsic defect nor an extrinsic defect exists. Note that the threshold value is preferably measured and determined in advance.

Similarly, the “second threshold value” is the second region of light generated from the site where the intrinsic defect of the solar cell element is present by injecting current into the solar cell element in the above-described current injection step. The emission intensity may be a value that is slightly lower than the emission intensity of the light in the second region generated from the site where the intrinsic defect exists, for example, about 90%, 80%, 70%, 60%, 50% May be the value.
<1-8. Evaluation under actual operating conditions>
The solar cell module evaluation method described above can be applied to all types of solar cell modules. That is, the evaluation method described above is for an arbitrary solar cell module composed of a crystalline or amorphous solar cell element, a compound semiconductor solar cell element, a dye-sensitized solar cell element, an organic solar cell element, or the like. Can be applied. For example, the solar cell element constituting the solar cell module to be evaluated by the evaluation method is not particularly limited as long as it is a solar cell element having various semiconductor materials as main components. It is preferable to include a silicon semiconductor as a main constituent member. Moreover, it is preferable that the silicon semiconductor used for the said solar cell element is a single crystal, a polycrystal, or an amorphous silicon semiconductor. In this specification, “providing as a main constituent member” means that any other member or component may be provided as long as a silicon semiconductor is provided as a main constituent member.

  Especially, it is preferable that it is a solar cell element provided with a polycrystalline silicon semiconductor as a main structural member. When a solar cell element is produced using a polycrystalline silicon semiconductor as a main constituent member, it is difficult to obtain a uniform in-plane distribution, so quality evaluation and performance check using the above evaluation method are very important. It will be a thing.

  In addition, when current is injected in a forward direction into a solar cell module having a single crystal and / or polycrystalline silicon semiconductor as a main component, light in a wavelength region of 1000 nm to 1300 nm is strongly emitted. Therefore, in the above evaluation method, the performance of the solar cell module can be more accurately evaluated by detecting the emission intensity particularly in the wavelength region of 1000 nm to 1300 nm.

In the first current injection step and the second current injection step, the current density to be injected is preferably substantially the same as the operating current of the solar cell module. Here, the “operating current of the solar cell module” means a current actually generated by photoelectric conversion when the solar cell element to be evaluated is irradiated with sunlight. For example, in the case of a solar cell element made of silicon semiconductor, it is 5 to 40 mA / cm ² , but is not limited to this value, and is appropriately determined depending on the materials and compositions of various solar cell elements and various solar cell modules. Needless to say, it can be changed. In addition, the rational numerical range which can show the effect of this invention even if it is out of the said numerical range is included in the technical scope of this invention.

  It is preferable to use a long pass filter (1R pass 900 nm or more pass) for the third image of the solar cell element including a polycrystalline silicon semiconductor as a tumor constituent member. When light emission having a wavelength of 900 nm or more in the third image is observed, it can be confirmed that a white to black portion is present in the third image. Thus, in the third image, the white part (light emitting part) is a normal part having neither intrinsic defect nor extrinsic defect, and the black part (part not emitting light) is the intrinsic defect. Alternatively, it can be identified that the site has an extrinsic defect. That is, it can be determined that an intrinsic defect or an extrinsic defect exists even under light irradiation.

  Thus, the photoelectric conversion performance and / or reliability of the solar cell module can be more accurately evaluated by performing evaluation under actual operating conditions. However, the conditions for performing the solar cell module evaluation method of the present invention are not limited to such actual operating conditions, and vary according to the relationship between the camera performance, exposure time, and amount of defects, and those skilled in the art appropriately determine the optimum conditions. Can be set.

  As described above, according to the evaluation method of the present invention, it does not require special equipment such as a dark room even under strong light irradiation such as sunlight, compared to the conventional evaluation method of a solar cell module. The performance of the solar cell module can be evaluated. Moreover, according to the said evaluation method, quantitative evaluation about the performance of a solar cell module is also possible. Furthermore, according to the said evaluation method, the magnitude | size of the solar cell module used as evaluation object is not specifically limited, The thing of various magnitude | sizes can be used. For example, it can be used for a “solar cell panel” that is an assembly of solar cell modules, and a “mega solar system” that is an assembly of the “solar cell panels”.

  Moreover, the solar cell module evaluation method of the present invention can be applied to the manufacturing process of the solar cell module. According to this, in the manufacturing process of a solar cell module, it becomes possible to detect a defective solar cell module by constantly monitoring the emission intensity of light from the solar cell module. For this reason, it is possible to repair or replace defective products.

Thus, since the manufacturing method of a solar cell module includes the above-described evaluation method as one step, 100% inspection can be automatically performed, and a non-defective solar cell module can be provided.
<2. Evaluation device for solar cell module>
The solar cell module evaluation apparatus of the present invention is an evaluation apparatus for a solar cell module under light irradiation, and is a first current injection unit (first current injection unit) for injecting a current in the forward direction to the solar cell module. Injection means), a second current injection section (second current injection means) for injecting a current smaller than the current injected by the first current injection section in the forward direction with respect to the solar cell module, As an image of the solar cell module, a first image in a state where current is injected by the first current injection unit, and a second image in a state where current is injected by the second current injection unit And an image acquisition unit (image acquisition means) for acquiring the difference between the first image and the second image, and for current injection at the first current injection unit to the solar cell module A third representing the resulting emission state An image forming unit (image forming unit) that acquires an image and a determination unit (determination unit) that determines the performance of the solar cell module based on the third image may be provided. There are no particular restrictions on conditions such as the general configuration, size, and shape.

  Moreover, the solar cell module evaluation apparatus of the present invention includes, in the light emission generated in the third image, light in a first region having a wavelength of 800 nm to 1300 nm and light in a second region having a wavelength of 1400 nm to 1800 nm. A light emission detection unit (light emission detection means) for detecting is further included. In the determination unit, the light emission intensity of the first region and the light emission intensity of the second region detected by the light emission detection unit are used as indices. It is possible to distinguish between intrinsic defects and extrinsic defects.

  Hereafter, each said member (each means) is demonstrated in detail. In addition, since the evaluation device for the solar cell module can also be said to execute the evaluation method for the solar cell module, for the description of each member, the description of each step in the evaluation method is cited. The overlapping part is omitted.

<2-1. Current injection part>
The first current injection unit and the second current injection unit are not particularly limited as long as the first current injection unit and the second current injection unit inject a current in the forward direction with respect to the solar cell module. . The first current injection part and the second current injection part may be the same member or different members. In other words, it can be said that the current injection part only needs to execute the “current injection process” described in the sections <1-1> and <1-3>. For example, various constant current sources and constant voltage sources can be used. When direct current is injected, various direct current power sources may be used as the current injection portion.

  Photovoltaic power is generated by photoelectric conversion in the solar cell module under light irradiation. For this reason, it is preferable that a 1st electric current injection | pouring part is an apparatus which inject | pours the electric current equivalent to applying the voltage exceeding the photovoltaic power generated in a solar cell module under light irradiation. Furthermore, the second current injection unit may be a device that injects a smaller current than the first current injection unit. For example, the second current injection unit is equal to or greater than the photovoltaic power generated by the solar cell module under light irradiation. It is preferable that current is injected by applying a voltage, or a device that does not inject current may be used.

  The first current injection unit and the second current injection unit preferably inject a current having substantially the same current density as the operating current of the solar cell element constituting the solar cell module. For example, the first current injection unit and the second current injection unit inject a current having a current density in the range described in the section <1-8> in order to generate light with higher emission intensity. May be.

  About the other structure, description of the said <1-1> and <1-3> column is used.

<2-2. Image acquisition unit>
The image acquisition unit includes a first image in a state where current is injected by the first current injection unit and a state where current is injected by the second current injection unit as an image of the solar cell module. As long as the second image is acquired, the specific configuration and the like are not particularly limited.

  In other words, the main image acquisition unit only needs to execute the “image acquisition process” described in the sections <1-2> and <1-4>. For example, various photodetectors such as the above-described InGaAs camera, CCD camera, or image intensifier can be suitably used. About the other structure, description of the said <1-2> and <1-4> column is used.

<2-3. Image forming unit>
The image forming unit analyzes the difference between the first image and the second image obtained by the image acquisition unit, and performs current injection at the first current injection unit to the solar cell module. What is necessary is just to acquire the 3rd image showing the light emission state which originates, and the specific structure etc. are not specifically limited.

  That is, by analyzing the difference between the first image and the second image, light other than the electroluminescence of the solar cell module, that is, background light, disturbance light, etc. under light irradiation is excluded, and the first substantially What is necessary is just to acquire the image which analyzes only the electroluminescence of the solar cell module resulting from this current injection process. For example, the image forming unit only needs to execute the “image forming step” described in the section <1-5>. For other configurations, the description in the above section <1-5> is incorporated.

<2-4. Luminescence detector>
The light emission detection unit only needs to detect light in the first region having a wavelength of 800 nm to 1300 nm and light in the second region having a wavelength of 1400 nm to 1800 nm among the light emission generated in the third image. The specific method thereof is not particularly limited, and a conventionally known technique can be suitably used.

  That is, the light emission detection unit may be any unit that performs the “light emission detection step” described in the section <1-6>. For example, various photodetectors such as the above-described InGaAs camera, CCD camera, or image intensifier can be suitably used. About the other structure, description of the said <1-6> column is used.

<2-5. Judgment part>
The determination unit determines the performance of the solar cell module based on the third image obtained by the image forming unit, and the specific configuration thereof is not particularly limited. The determination unit determines whether the defect in the solar cell module is due to an intrinsic defect or an extrinsic defect based on light emission of the third image obtained by the light emission detection unit. It is preferable. That is, the determination unit only needs to execute the “determination step” described in the section <1-7>, and for example, various arithmetic devices such as a computer can be suitably used.

  The determination unit uses the intensity of the electroluminescence emission intensity of the solar cell module obtained from the third image as an index, and when the emission intensity in the third image is greater than a predetermined value, When the performance is determined to be good and the emission intensity in the third image is smaller than a predetermined value, the performance of the solar cell module is determined to be poor.

  The determination unit separates an intrinsic defect from an extrinsic defect using the light emission intensity of the first region detected by the light emission detection unit and the light emission intensity of the second region as an index. It is. About the other structure, description of the said <1-7> column is used.

<2-6. Embodiment of Evaluation Device for Solar Cell Module>
Based on FIG. 1, one Embodiment of the evaluation apparatus 10 of the solar cell module of this invention is described. As shown in FIG. 1, the solar cell module evaluation apparatus 10 according to the present embodiment includes an image acquisition unit 12, a comb probe 3, a copper plate 4, a DC power source 5, and an image processor 7. Moreover, the evaluation apparatus 10 makes the solar cell module 6 evaluation object. The solar cell module 6 has a configuration in which a plurality of solar cell elements are connected.

  The image acquisition unit 12 functions as an image acquisition device including a CCD camera. The image acquisition unit 12 includes an InGaAs CCD camera 1 and a lens 2. The image acquisition unit 12 is formed to be rotatable by 90 °. Thereby, the solar cell module provided in the parallel direction and the vertical direction can be evaluated.

  As the lens 2, a normal lens or a zoom lens can be used.

  In addition, when an InGaAs CCD camera 1 is used as the image acquisition unit 12 and a cell (solar cell element) constituting the solar cell module 6 having a different size is evaluated, the performance described in Table 1 below is obtained. Also good.

  Specifically, in the module shooting mode, as shown in FIG. 1, the CCD camera is installed in the parallel direction of the solar cell module for shooting, but in the normal shooting mode, the CCD camera is rotated by 90 ° to obtain the CCD. A camera is installed on the top of the solar cell module to take and measure.

  The size (cell size) of the solar cell module 6 to be evaluated in the normal photographing mode is, for example, a size: about 10 mm × 10 mm, 20 mm × 20 mm, 100 mm × 100 mm, 150 mm × 150 mm, 160 mm × 160 mm, The thing of 200 mm x 200 mm and thickness: 0.3 mm or less can be used.

  Moreover, in this embodiment, the distance between the image acquisition unit 12 lens 2 and the solar cell module 6 is set to 150 mm or more and 400 mm or less, and the image acquisition unit 12 is installed to be movable between the solar cell module 6. It is preferred that

  The comb probe 3 is a surface contact for injecting current into the solar cell module 6. The comb probe 3 is composed of a pair of comb-shaped probes as shown in the figure, and one comb corresponds to one electrode of the solar cell element constituting the solar cell module 6. It is preferable that the probe has a comb structure because a current can be uniformly injected into the solar cell module 6.

  In particular, the comb probe 3 used for the 100 mm × 100 mm cell, 150 mm × 150 mm cell, and 200 mm × 200 mm cell may have different lengths of the pass bar electrodes and widths between the two electrodes. For example, a pair of comb-shaped probes manufactured by Atosystem can be used. In this case, it is preferable that the width interval between the two comb-shaped probes is configured to be adjustable. Moreover, although the space | interval of the "comb" in a comb-shaped probe is not specifically limited, For example, what is necessary is just 9 mm. Moreover, the thickness of one comb of the probe can be 1 mm. One comb probe 3 is preferably used for each electrode.

  In addition, when the solar cell module 6 is 10 mm × 10 mm or 20 mm × 20 mm, a probe (1 piece) from a positive shower may be used without using the comb probe 3.

  The copper plate 4 functions as a back contact. For example, a gold plated copper plate can be used. In this case, it is preferable to suck the entire surface of the solar cell module 6. For example, since the cell size changes, the stability is improved by digging and sucking a concentric square groove. Examples of the size of the groove include 8 mm × 8 mm, 18 mm × 18 mm, 98 mm × 98 mm, 148 mm × 148 mm, and 195 mm × 195 mm. Moreover, it is preferable to provide a temperature sensor and / or a cooling device. This is because the temperature of the solar cell module can be kept constant, and the measurement and evaluation accuracy is improved.

As the DC power supply 5, a normal DC power supply (which can be injected into a solar cell element at a current density of 1 × 10 ^{−3 to} 5 A / cm ² ) can be used. The voltage may be about 5V when evaluating solar cell elements or solar cell modules, but is preferably about 100V when evaluating solar cell panels that are aggregates of solar cell modules. In particular, the voltage is more preferably about 1 to 2 V per solar cell element.

  Further, the comb probe 3, the copper plate 4, and the DC power source 5 function as a current injection unit 11. The comb probe 3 is fixedly connected to the negative side of the DC power supply 5, and the copper plate 4 is fixedly connected to the positive side of the DC power supply 5. In the present embodiment, the current injection unit 11 functions as a first current injection unit and a second current injection unit.

In the present embodiment, the image processor 7 functions as the image forming unit 13, the determination unit 14, and the control unit 15. From the difference between the first image and the second image obtained by the image acquisition unit 12, the image forming unit 13 emits light from the solar cell module 6 due to the current injected to obtain the first image. It functions as a device for acquiring a third image representing the above. The determination unit 14 functions as a determination device that evaluates the performance of the solar cell module 6. The control unit 15 functions to give an instruction to acquire the second image after obtaining the first image, or functions to give an instruction to acquire the third image. The operation of the so-called evaluation apparatus as a whole is controlled. The software used for the image processor 7 is not particularly limited as long as the object of the present invention can be achieved. For example, software having the following configuration is preferably used.
An image that can store ⁸ bits (2 ⁸ = 256 gradations) or 16 bits (2 ¹⁶ = 65536 gradations).
・ Those that can detect / photograph light generated from solar electronic elements, select the area on the screen, and acquire / save brightness profile data.
・ Spectrostable.
・ Those that can acquire high-sensitivity images (image intensifier cameras), for example, those that can measure emissions during reverse current injection.

Further, the following configuration is more preferable.
・ Improved that when the data is read with spreadsheet software and converted into an image, the photographed image is rotated 90 degrees.
・ Simple switching of binning mode is possible.
・ Automatic creation program for histogram of light emission intensity.
・ Automatic measurement of length and width of low intensity (dark areas). Automatic detection of one centimeter or more.
・ Calculate the average value of the light emission intensity in the selected range. It is preferable that an average value obtained by subtracting the value of the grid portion can also be measured.

  In the case of this embodiment, the image acquisition unit 12 is provided in the parallel direction of the solar cell module 6.

  Next, an embodiment of the evaluation operation of the solar cell module evaluation apparatus 10 will be described with reference to FIG. The evaluation device 10 includes a current injection unit 11, an image acquisition unit 12, an image formation unit 13, a determination unit 14, and a control unit 15. The current injection unit 11, the image acquisition unit 12, and the image forming unit 13 are connected via the control unit 15, and the image forming unit 13 is connected to the determination unit 14.

  The current injection unit 11, the image acquisition unit 12, the image forming unit 13, and the determination unit 14 execute the image acquisition process, the current injection process, the image formation process, and the determination process, respectively.

  First, the current injection unit 11 injects a current into the solar cell module 6. The solar cell module 6 emits light by current injection (electroluminescence). However, since it is under light irradiation, weak electroluminescence cannot be observed with the naked eye. Next, the image acquisition unit 12 acquires a first image representing the light emission state of the solar cell module 6. The acquired first image information is sent to the control unit 15 and stored.

  Next, the current injection unit 11 injects a smaller current into the solar cell module 6 than when the first image is acquired. At this time, the control unit 15 may transmit the current injection unit 11 so as to inject a smaller current than when the first image is acquired. Next, the image acquisition unit 12 acquires a second image representing the light emission state of the solar cell module 6 into which the current is injected. The acquired second image information is sent to the control unit 15 and stored.

  The first image information and the second image information stored in the control unit 15 are transmitted to the image forming unit 13. The image forming unit 13 analyzes the difference between the first image information and the second image information, and represents the light emission state of the solar cell module 6 caused by the current injected when the first image is acquired. A third image is formed. The third image information is sent to the determination unit 14. The determination unit 14 compares the light emission intensity of the solar cell module 6 with a predetermined value set in advance based on the third image, and determines the performance of defects or the like existing in the solar cell module.

  The first image information and the second image information may be sequentially sent from the control unit 15 to the image forming unit 13 or may be sent simultaneously. The first image information and the second image information may be sent directly from the image acquisition unit 12 to the image forming unit 13 without using the control unit 15.

  As described above, according to the solar cell module evaluation apparatus of the present invention, the solar cell module evaluation method described in the section <1> can be simply and reliably performed. In this case, the performance of the solar cell module can be quantitatively evaluated without requiring special equipment such as a dark room even under the irradiation of strong light such as sunlight as in the prior art.

<3. Use of solar cell module evaluation methods, etc.>
As described above, the solar cell module evaluation method and evaluation apparatus according to the present invention do not require special equipment such as a dark room even under irradiation of strong light such as sunlight. For this reason, according to the solar cell module evaluation method or evaluation apparatus of the present invention, it is possible to observe and evaluate in the product state (the state completed in the manufacturing factory, or the state installed in the structure), For example, a business model such as a maintenance method or a maintenance system that periodically evaluates solar cell modules installed in a structure can be constructed.

  That is, in the present invention, the evaluation device for the solar cell module described above evaluates the performance of the solar cell module installed in the structure, and the replacement instruction device is based on the inspection result in the evaluation step. A method for instructing a solar cell module replacement operator to replace a defective portion of the solar cell module via a communication network.

  The present invention also includes a maintenance system for executing the maintenance method. The maintenance system instructs the solar cell module replacement operator via the communication network to replace the solar cell module based on the solar cell module evaluation device of the present invention and the evaluation result of the evaluation device. What is necessary is just to provide an exchange instruction | indication apparatus.

  In the present specification, the term “solar cell module installed in a structure” means a solar module already installed in a structure such as a residential facility such as a house and a condominium, a commercial facility such as a shopping mall or an office building. A battery module is intended. For example, in a solar cell module manufacturing factory, a solar cell module that is being manufactured or has just been manufactured and that is not installed in a structure is excluded.

  FIG. 3 is a functional block diagram schematically showing an example of the maintenance system 100 according to the present embodiment. As shown in the figure, the maintenance system 100 includes an evaluation device 10 and a replacement instruction device 20. The evaluation device 10 includes a current injection unit 11, an image acquisition unit 12, an image formation unit 13, a determination unit 14, and a control unit 15. In addition, about the member which has the same function as the member demonstrated in FIG. 2, the same code | symbol is attached and the description is abbreviate | omitted.

  The exchange instruction device 20 is connected to the determination unit 14 provided in the evaluation device 10. Further, the exchange instruction device 20 is connected to the exchange operator's terminal 40 via the communication network 30. Note that the communication network 30 and / or the exchange operator's terminal 40 may be included in the maintenance system 100, or an external arbitrary network or an arbitrary terminal may be used.

  The replacement instruction device 20 replaces a solar cell module whose light emission intensity is lower than a predetermined value and is judged to have deteriorated performance, and replaces the solar cell module via a communication network. It is an instruction to the person. For example, the exchange instruction device 20 is not particularly limited, and an arithmetic device such as a computer that can be connected to a communication line such as the Internet can be used.

  In the present embodiment, the determination unit 14 and the replacement instruction device 20 are described as separate devices, but it goes without saying that one computer can be used as the determination unit 14 and the replacement instruction device 20.

  Further, the communication network 30 is not particularly limited, but may be a dedicated line using a wire or a line such as the Internet. Further, as the communication network 30, a network using a mobile phone line or radio can be used.

  The terminal 40 of the exchange operator may be any terminal that can recognize the exchange instruction from the exchange instruction apparatus 20. The terminal 40 of the exchange operator is not particularly limited, but preferably includes a display unit (for example, a display such as a CRT or LCD) or an output unit (for example, a printer).

  Next, FIG. 4 shows an example of a flow of the maintenance system 100 according to the embodiment using the evaluation device 10. First, the first image and the second image are acquired by the evaluation device 10, and then the difference between the first image and the second image is analyzed and injected to obtain the first image. A third image representing the light emission state of the solar cell module 6 due to the current is formed. Then, the evaluation apparatus 10 determines whether or not the emission intensity of the third image is lower than a preset value. If the light emission intensity of the third image is lower than a preset value based on the determination, it is determined that the performance of the solar cell module is degraded. When it is determined that the performance of the solar cell module is deteriorated, the exchange operator is requested to examine whether or not to replace the solar cell module.

  More specifically, first, in the maintenance system 100, the current injection unit 11 of the evaluation device 10 performs a current injection process on the solar cell module to be maintained (step 1, hereinafter, step is described as “S”). ). Next, the image acquisition unit 12 in the evaluation device 10 acquires an image (first image) of the solar cell module that has performed the process of S1 (S2).

  Next, the current injection unit 11 performs a current injection process on the solar cell module (S3). Next, the image acquisition part 12 acquires the image (2nd image) of the solar cell module which performed the process of S3 (S4). Note that the control unit 15 determines whether the image acquired in S2 is the second image, and when the acquired image is the first image, repeats S1 and S2 once again to acquire the second image. The current injection unit 11 may be instructed to do so.

  The acquired information on the first image and information on the second image are sent to the image forming unit 13 (S5). The image forming unit 13 analyzes the difference between the acquired first image and the second image, and a third image representing the light emission state of the solar cell module 6 due to the current injected to obtain the first image. Is formed (S6).

  Next, the determination unit 14 determines whether the emission intensity of the third image is equal to or less than a preset value based on the third image (S7). In S7, when the determination unit 14 determines that the emission intensity of the third image is equal to or less than a preset value (“Y”), the process proceeds to S8. In S <b> 8, the determination unit 14 determines that the performance of the solar cell module with low emission intensity is degraded, and transmits this result to the replacement instruction device 20. The process proceeds to S9. In S9, the exchange instructing device 20 notifies the exchange operator's terminal 40 of the presence of the solar cell module whose performance is deteriorated via the communication network 30, and the exchange is performed. Ask the exchange operator to consider whether or not to do so, and end the process.

  On the other hand, if the determination unit 14 determines in step S7 that the emission intensity of the third image is greater than a preset value (“N”), the process ends as it is.

  Conventionally, in order to evaluate a solar cell module, it is necessary to use a large device and in a dark room, evaluate the performance of the solar cell module installed in a structure such as a house, and perform regular maintenance. It was difficult to do. However, according to the maintenance method or maintenance system of the solar cell module of the present invention, it is possible to evaluate the performance of the solar cell module without requiring special equipment such as a dark room even under irradiation of strong light such as sunlight. . For this reason, even if it is the solar cell module already installed in the structure (namely, produced solar cell module), it is possible to perform maintenance periodically. Therefore, the quality of the solar cell module can be maintained at a certain level.

  In the above description, the maintenance method and the maintenance system using some examples of the solar cell module evaluation apparatus have been described. Naturally, the maintenance method and the maintenance system include various types of devices described in this specification. It should be noted that a solar cell module evaluation apparatus can be suitably used.

  Finally, each block of the maintenance system such as the evaluation device and the replacement instruction device (hereinafter simply referred to as “evaluation device”) is realized by a logic circuit (hardware) formed on an integrated circuit (IC chip) or the like. Alternatively, it may be realized by software using a CPU (Central Processing Unit).

  In the latter case, the evaluation apparatus or the like includes a CPU that executes instructions of a program that is software that realizes each function, a ROM (Read Only Memory) in which the program and various data are recorded so as to be readable by a computer (or CPU), or A storage device (these are referred to as “recording media”), a RAM (Random Access Memory) for expanding the program, and the like are provided. And the objective of this invention is achieved when a computer (or CPU) reads the said program from the said recording medium and runs it. As the recording medium, a “non-temporary tangible medium” such as a tape, a disk, a card, a semiconductor memory, a programmable logic circuit, or the like can be used. The program may be supplied to the computer via an arbitrary transmission medium (such as a communication network or a broadcast wave) that can transmit the program. The present invention can also be realized in the form of a data signal embedded in a carrier wave in which the program is embodied by electronic transmission.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and the technical means (apparatus) disclosed in different embodiments can be appropriately combined. Such embodiments are also included in the technical scope of the present invention. EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited only to this Example.

[Example 1: Evaluation 1 under incandescent bulb illumination]
The performance of a commercially available polycrystalline silicon semiconductor solar cell module (conversion efficiency about 13%, manufactured by Bp Solar, SX20M) was evaluated under incandescent lamp irradiation. In this example, a Si CCD camera (manufactured by Hamamatsu Photonics Co., Ltd., product number C9299-02) was used to analyze the solar cell module. The size of the polycrystalline silicon semiconductor solar cell module used is 40 cm × 50 cm.

FIG. 5 shows an image of the solar cell module obtained in this example. FIG. 5A is an image (first image) of a light emitting state of a solar cell module in which a direct current of 5 A is injected in the forward direction under incandescent bulb irradiation. FIG.5 (b) is an image (2nd image) of the solar cell module without an electric current injection under incandescent lamp irradiation. FIG.5 (c) is an image (first image) representing the light emission state of the solar cell module resulting from the injection of the direct current (5A), obtained by analyzing the difference between the first image and the second image. 3 image). FIG.5 (d) is the image which showed the light emission state of the same solar cell module which inject | poured the electric current whose current density is 40 mA / cm < ² > in a dark room.

  First, when FIG. 5C and FIG. 5D are compared, the regions of the intensity of light emission match. From this result, it is understood that the performance of the solar cell module can be evaluated by acquiring the difference between the first image and the second image even under incandescent bulb irradiation, similarly to the observation of electroluminescence in a dark room.

  As shown in FIG.5 (c), it turns out that the electroluminescence resulting from the electric current injection | pouring to the said solar cell module can be observed also under light irradiation. The portion that appears whitish is a region that emits strong light, and the portion that appears black is a region where light emission is weak. A region surrounded by a broken line in FIG. 5C is a region where light emission is weak, and it can be seen that the region is a defective region of the solar cell module.

[Example 2: Evaluation 2 under incandescent bulb illumination]
The performance of the high-efficiency single crystal silicon element A (conversion efficiency 18 to 19%, prototype) having higher emission intensity than the solar cell module used in Example 1 was evaluated under incandescent lamp irradiation. The size of the high-efficiency single crystal silicon element A used is 10 cm × 10 cm. In addition, it carried out similarly to Example 1 except the structure mentioned above.

FIG. 6 shows an image of the high-efficiency single crystal silicon element A obtained in this example. FIG. 6A is an image (first image) of a light emission state of the high-efficiency single crystal silicon element A in which a direct current of 4 A is injected in the forward direction under illumination of an incandescent bulb. FIG. 6B is an image (second image) of the high-efficiency single crystal silicon element A with no current injection under incandescent lamp irradiation. FIG. 6C shows the light emission state of the high-efficiency single crystal silicon element A resulting from the injection of the direct current (4A), obtained by analyzing the difference between the first image and the second image. It is the image (3rd image) to represent. FIG. 6D is an image showing a light emission state of the same high-efficiency single crystal silicon element A in which a current having a current density of 40 mA / cm ² is injected in a dark place.

  When FIG. 6C and FIG. 6D are compared, the regions of light emission intensity match. From this result, the performance of the high-efficiency single crystal silicon element A is evaluated by obtaining the difference between the first image and the second image even under incandescent bulb irradiation, similar to the observation of electroluminescence in a dark room. I understand that I can do it.

  As shown in FIG. 6C, it can be seen that electroluminescence due to current injection into the high-efficiency single crystal silicon element A can be observed even under light irradiation. The portion that appears whitish is a region that emits strong light, and the portion that appears black is a region where light emission is weak. A region surrounded by a broken line in FIG. 6C is a region where light emission is weak, and it can be seen that the region is a defective region of the solar cell module.

[Example 3: Evaluation 1 under solar simulator]
The performance of the solar cell module of high-efficiency single crystal silicon element A (conversion efficiency: 18 to 19%, prototype) was evaluated under light (1 sun) irradiation by a solar simulator (manufactured by WACOM). The size of the used solar cell module is 10 cm × 10 cm. In addition, it carried out similarly to Example 1 except the structure mentioned above.

  FIG. 7 shows an image of the solar cell module obtained in this example. FIG. 7A is an image (first image) of a light emission state of a solar cell module in which a direct current of 12 A is injected in the forward direction under light (1 sun) irradiation. FIG. 7B is an image (second image) of the solar cell module without current injection under light (1 sun) irradiation. FIG. 7C is an image (first image) representing the light emission state of the solar cell module resulting from the injection of the direct current (12A), obtained by analyzing the difference between the first image and the second image. 3 image). FIG.7 (d) is the image which showed the light emission state of the same solar cell module which inject | poured the electric current of 12A in the dark room.

  When FIG. 7C and FIG. 7D are compared, the regions of light emission intensity match. From this result, even under light irradiation by a solar simulator, by evaluating the difference between the first image and the second image, the performance of the solar cell module is evaluated in the same manner as the observation of electroluminescence in a dark room. I found out that

  As shown in FIG.7 (c), it turns out that electroluminescence resulting from injection | pouring of the direct current to the said solar cell module can be observed also under light irradiation. The portion that appears whitish is a region that emits strong light, and the portion that appears black is a region where light emission is weak. A region surrounded by a broken line in FIG. 7C is a region where light emission is weak and is a defective region of the solar cell module.

[Example 4: Evaluation 2 under solar simulator]
The performance of the high efficiency single crystal silicon element B solar cell module (conversion efficiency 18-19%, prototype) was evaluated under light (1 sun) irradiation by a solar simulator (manufactured by WACOM). The size of the used solar cell module is 10 cm × 10 cm. In addition, it carried out similarly to Example 1 except the structure mentioned above.

  FIG. 8 shows an image of the solar cell module obtained in this example. FIG. 8A is an image (first image) of a light emitting state of a solar cell module in which a direct current of 5 A is injected in the forward direction under light (1 sun) irradiation. FIG. 8B is an image (second image) of the solar cell module without current injection under light (1 sun) irradiation. FIG. 8C is an image (first image) representing the light emission state of the solar cell module resulting from the injection of the direct current (5A), obtained by analyzing the difference between the first image and the second image. 3 image). FIG. 8D is an image showing the light emission state of the same solar cell module injected with a current of 5 A in the dark room. FIG. 8 (e) is the color image of FIG. 8 (d), and FIG. 8 (f) is the color image of FIG. 8 (c). In the case of a color image, a red portion is a region where light is emitted strongly, and a yellow to blue portion is a region where light emission is weak.

  Comparing FIG. 8C and FIG. 8D, and comparing FIG. 8E and FIG. 8F, it can be seen that the emission intensity regions match. From this result, even when the injected current is weakened, the solar cell is obtained in the same manner as in the observation of electroluminescence in the dark room by obtaining the difference between the first image and the second image under light irradiation by the solar simulator. It was found that the performance of the module can be evaluated.

  As shown in FIG. 8 (c), it can be seen that even under light irradiation, electroluminescence caused by direct current injection into the solar cell module can be observed. The portion that appears whitish is a region where light is emitted strongly, and the portion that appears black is a region where light emission is weak, which is a defective region of the solar cell module.

[Example 5: Evaluation 3 under solar simulator]
A part of the solar cell module (conversion efficiency: 18 to 19%, prototype) of the same high-efficiency single crystal silicon element C used in Example 2 was destroyed, and an exogenous defect was intentionally produced. The performance of the high-efficiency single crystal silicon element C was evaluated under light (1 sun) irradiation by a solar simulator (manufactured by WACOM). The size of the high-efficiency single crystal silicon element C used is 10 cm × 10 cm. In addition, it carried out similarly to Example 1 except the structure mentioned above.

  FIG. 9 shows an image of the high-efficiency single crystal silicon element C obtained in this example. FIG. 9A is an image (first image) of a light emission state of the high-efficiency single crystal silicon element C in which a direct current of 12 A is injected in the forward direction under light (1 sun) irradiation. FIG. 9B is an image (second image) of the high-efficiency single crystal silicon element C without current injection under light (1 sun) irradiation. FIG. 9C shows the light emission state of the high-efficiency single crystal silicon element C resulting from the injection of the direct current (12A) obtained by analyzing the difference between the first image and the second image. It is the image (3rd image) to represent. FIG. 9D is an image showing a state of light emission of the same high-efficiency single crystal silicon element C in which a current of 12 A is injected in a dark place.

  Comparing FIG. 9C and FIG. 9D, it can be seen that the shape of the light emission intensity region, in particular, the weak region (such as a region caused by an extrinsic defect) matches. From this result, even under light irradiation by a solar simulator (manufactured by WACOM), by obtaining the difference between the first image and the second image, it is due to an extrinsic defect, similar to the observation of electroluminescence in a dark room. It was found that the performance can be evaluated even when the performance is lowered. As shown in FIG. 9C, it can be seen that even under light irradiation, electroluminescence resulting from the injection of 12 A direct current into the high-efficiency single crystal silicon element C can be observed. The portion that appears whitish is a region where light is emitted strongly, and the portion that appears black is a region where light emission is weak, which is a defective region of the solar cell module.

  According to the present invention, not only the performance evaluation, quality inspection, and element material evaluation performed when manufacturing the solar cell module, but also the installed solar cell module or the regular period of the mega solar system is performed. It can also be used for maintenance. For this reason, it can be used for a wide range of industries as well as mere inspection devices.

10 Evaluation Device 11 Current Injection Unit (Current Injection Means)
12 Image acquisition unit (image acquisition means)
13 Image forming unit (image forming means)
14 determination unit (determination device, determination means)
DESCRIPTION OF SYMBOLS 15 Control part 20 Exchange instruction | indication apparatus 30 Communication network 40 Terminal of exchange operator 100 Maintenance system

Claims (21)

A method for evaluating a solar cell module under light irradiation,
A first current injection step of injecting a current in the forward direction to the solar cell module;
A first image acquisition step of acquiring a first image of the solar cell module in a state where current is injected in the first current injection step;
A second current injection step of injecting a smaller current than the first current injection step in the forward direction with respect to the solar cell module;
A second image acquisition step of acquiring a second image of the solar cell module in a state where a current is injected in the second current injection step;
Image formation for analyzing a difference between the first image and the second image to obtain a third image representing a light emission state caused by current injection in the first current injection step to the solar cell module Process,
And a determination step of determining the performance of the solar cell module based on the third image.   The method for evaluating a solar cell module according to claim 1, wherein in the first current injection step, a current exceeding the photovoltaic power is applied to the solar cell module to inject a current.   3. The solar cell according to claim 1, wherein in the second current injection step, a current is injected by applying a voltage equal to or higher than a photovoltaic power to the solar cell module. 4. Module evaluation method.   3. The solar cell module evaluation method according to claim 1, wherein no current is injected into the solar cell module in the second current injection step.   The image forming step performs the first image acquisition step and the second image acquisition step a plurality of times, averages the obtained plurality of first images and the second image, and calculates a difference between them. The evaluation method of the solar cell module of any one of Claims 1-4 including the process of acquiring a 3rd image from.   In the image forming process, the first image acquisition process and the second image acquisition process are alternately performed a plurality of times, and the image obtained from each first image acquisition process and the second image acquisition process are obtained. The method for evaluating a solar cell module according to claim 1, further comprising a step of obtaining a sum of differences from the obtained image.   The said image formation process includes the process of removing the light emission by the photovoltaic power resulting from the light irradiated to the said solar cell module by synchronous detection, and acquiring the 3rd image, It is characterized by the above-mentioned. The evaluation method of the solar cell module of any one of 4. A light emission detecting step of detecting light in a first region having a wavelength of 800 nm to 1300 nm and light in a second region having a wavelength of 1400 nm to 1800 nm among the light emission generated in the third image;
In the determination step, the intrinsic defect and the extrinsic defect are separated using the light emission intensity of the first region detected in the light emission detection step and the light emission intensity of the second region as an index. The evaluation method of the solar cell module according to any one of claims 1 to 7.   9. The solar cell module evaluation method according to claim 8, wherein in the light emission detection step, detection is performed using a band-pass filter that selectively allows light of 1150 nm to pass therethrough. An evaluation device for a solar cell module under light irradiation,
First current injection means for injecting current in the forward direction with respect to the solar cell module;
Second current injection means for injecting a current smaller than the current injected by the first current injection means in the forward direction with respect to the solar cell module;
As an image of the solar cell module, a first image in a state where current is injected by the first current injection means, and a second image in a state where current is injected by the second current injection means. And an image acquisition means for acquiring
Image formation for analyzing a difference between the first image and the second image to obtain a third image representing a light emission state caused by current injection by the first current injection means to the solar cell module Means,
An evaluation device for a solar cell module, comprising: determination means for determining performance of the solar cell module based on the third image.   The first current injection means applies current exceeding the photovoltaic power to the solar cell module when the image acquisition means acquires the first image, and current is injected. The solar cell module evaluation apparatus according to claim 10.   The second current injection unit applies a voltage equal to or higher than the photovoltaic power to the solar cell module when the image acquisition unit acquires the second image, and current is injected. The solar cell module evaluation apparatus according to claim 10, wherein the evaluation apparatus is a solar cell module evaluation apparatus.   The said 2nd electric current injection means does not inject an electric current with respect to the said solar cell module, when the said image acquisition means acquires a 2nd image, The Claim 10 or 11 characterized by the above-mentioned. Solar cell module evaluation device.   14. The image forming unit according to claim 10, wherein the image forming unit averages the plurality of first images and the second image, and acquires the third image from the difference. The evaluation apparatus of the solar cell module of any one.   The image forming means alternately performs acquisition of the first image and acquisition of the second image a plurality of times, and obtains a sum of differences between the first image and the second image at each time. The solar cell module evaluation apparatus according to any one of claims 10 to 14, wherein:   16. The image forming unit according to any one of claims 10 to 15, wherein the image forming unit acquires an image by removing light emission caused by photovoltaic power caused by light irradiated on the solar cell module by synchronous detection. The evaluation apparatus of the solar cell module of Claim 1. A light emission detecting means for detecting light in a first region having a wavelength of 800 nm to 1300 nm and light in a second region having a wavelength of 1400 nm to 1800 nm among the light emission generated in the third image;
In the determination unit, the intrinsic defect and the extrinsic defect are discriminated using the light emission intensity of the first region and the light emission intensity of the second region detected by the light emission detection unit as an index. The solar cell module evaluation apparatus according to any one of claims 10 to 16.   18. The solar cell module evaluation apparatus according to claim 17, wherein in the light emission detection means, detection is performed using a band-pass filter that selectively passes light of 1150 nm. An evaluation process for evaluating the performance of the solar cell module installed in the structure by the solar cell module evaluation apparatus according to any one of claims 10 to 18, and
A replacement instruction device including a step of instructing a replacement operator of the solar cell module to replace a defective portion of the solar cell module via a communication network based on the inspection result in the evaluation step. The maintenance method of the solar cell module. The solar cell module evaluation apparatus according to any one of claims 10 to 18,
A solar cell module comprising: a replacement instruction device for instructing a solar cell module replacement operator to replace the solar cell module via a communication network based on the evaluation result of the evaluation device. Maintenance system.   The manufacturing method of the solar cell module characterized by including the evaluation method of the solar cell module of any one of Claims 1-9 as 1 process.