JP4690878B2 - Solar cell module evaluation method and solar cell module evaluation apparatus - Google Patents

Description

  The present invention relates to a solar cell, and more particularly, to a solar cell module evaluation method and a solar cell module evaluation apparatus.

  A thin-film silicon solar cell (hereinafter referred to as a solar cell module) formed by laminating a silicon-based thin film on a light-transmitting substrate is known. FIG. 1 is a diagram showing a conventional solar cell module 110. The solar cell module 110 includes a substrate 101, a power generation cell 106, a protective film 102, and a waterproof sheet 103. The power generation cell 106 is provided inside the peripheral region 114 on the surface of the substrate 101. The protective film 102 is provided so as to cover the power generation cell 106 and the peripheral region 114 on the surface of the substrate 101, and is exemplified by EVA (ethylene vinyl acetate copolymer). The waterproof sheet 103 is provided so as to cover the protective film 102.

  The solar cell module 110 is housed in a metal frame 104 such as aluminum and is mainly used outdoors as a solar cell panel. When used outdoors, water 105 may accumulate in the gap between the solar cell module 110 and the metal frame 104 due to rain, snow, condensation due to temperature changes, and the like. When EVA is used as the protective film 102 in contact with the water 105, EVA is moisture permeable, so that moisture permeates the protective film 102 after a long period of time and enters the interface 101 a between the substrate 101 and the protective film 102. Water 107 will accumulate. Such water 107 reaches the power generation cell 106 and induces a chemical change to cause deterioration of the power generation cell 106.

In addition, the following degradation mechanism has been clarified for the first time from the inventors' research. FIG. 2 is a conceptual diagram illustrating the deterioration mechanism. The electric power generated by the power generation cell 106 of the solar cell module 110 is converted into alternating current by the inverter 108 via the cable 109a and taken out to the outside. At this time, the inverter 108 is grounded by the cable 109b. On the other hand, the metal frame 104 of the solar cell panel is also grounded by the cable 109d. At this time, when water 107 enters the interface 101a at the end of the power generation cell 106 due to long-term use, the power generation cell 106-cable 109a-inverter 108-cable 109b-ground (ground) 109c-cable 109d-metal frame A closed electric circuit of 104-water 107-power generation cell 6 is formed. Here, in the power generation cell 6, the water is more likely to be submerged due to peeling from the silicon film that has been altered due to the galvanic action or due to a decrease in the adhesive strength at the bonding portion between the protective film 102 and the substrate 101.

  Thus, since the solar cell panel causes deterioration due to water in outdoor use, it is necessary to inspect water resistance. As the inspection method, for example, there is a test described in JIS C 8938 “Environmental test method and durability test method of amorphous solar cell module”. FIG. 3 is a conceptual diagram showing an outline of a test method defined in the JIS. In this method, the solar cell module 110 is immersed in water, and a high voltage E is applied between the electrode and a reference electrode 117 provided in the water by a power source 115 to determine whether the solar cell module 110 has been altered or not. . As a similar method, there is a method of measuring a leak current with an ammeter 116 in FIG.

  However, in the method of JIS C 8938, the sensitivity is not necessarily sufficient to evaluate the presence or absence of alteration of the solar cell module 110 over a long period of time, and a small amount of water ingress before the occurrence of alteration is measured. I can't do that either. In the method of measuring the leakage current, it is necessary for the infiltrated water to form a leakage circuit, and this is an inspection at the stage where the modification of the solar cell module 110 has already started. Infiltration of trace amounts of water cannot be measured. There is a need for a method with high inspection sensitivity that can measure the amount of intrusion of a small amount of water in a stage before the deterioration of the solar cell module 110 occurs.

  Japanese Unexamined Patent Application Publication No. 2003-207474 discloses a capacitance moisture meter. In this capacitance type moisture meter, a pair of handle members (2A, 2B) formed as grips (23) on the front side is attached to the tip side, and the hand side is rotatable with respect to each other. A gripping tool (1) configured to hold the object to be measured (6) between a pair of electrode plates (3A, 3B) facing each other by opening and closing the grip portion. The measurement circuit (7) for detecting the capacitance of the object to be measured (6) sandwiched between the pair of electrode plates and determining the moisture content of the object to be measured from the measurement circuit (7); And a circuit case (4) attached to an appropriate portion of the tool.

"JIS C 8938 Amorphous Solar Cell Module Environmental Test Method and Durability Test Method", 1995 JP 2003-207474 A

  Accordingly, an object of the present invention is to provide a solar cell module evaluation method and a solar cell module evaluation device capable of measuring the intrusion of a small amount of water at a stage before the deterioration of the solar cell module occurs.

  Another object of the present invention is to provide a solar cell module evaluation method and a solar cell module evaluation apparatus capable of evaluating the lifetime of the solar cell module.

  Hereinafter, means for solving the problem will be described using the numbers and symbols used in the best mode for carrying out the invention. These numbers and symbols are added in parentheses in order to clarify the correspondence between the description of the claims and the best mode for carrying out the invention. However, these numbers and symbols should not be used for interpreting the technical scope of the invention described in the claims.

The solar cell module evaluation method of the present invention includes (a) a step of measuring a first capacitance between a first position (P1) and a second position (P2) of the solar cell module (10); b) exposing the solar cell module (10) to a high humidity environment; and (c) after exposure to the high humidity environment, between the first position (P1) and the second position (P2) of the solar cell module (10). Measuring a second capacitance, and (d) evaluating a flooded state of the solar cell module (10) based on the first capacitance and the second capacitance. The solar cell module (10) is provided apart from the substrate (1), the first side (1a) of the substrate (1), the transparent conductive layer (11), the photoelectric conversion layer (12), and the substrate (1). A power generation cell (6) including the back electrode layer (13) in this order, and a protective layer (2) covering the substrate (1) and the power generation cell (6) are provided. The second position (P2) is a position on the protective layer (2) in the vicinity of the first side (1a). The first position (P1) is on the substrate (1) opposite to the power generation cell (6) and is first from the first end (E1) on the first side (1a) side of the power generation cell (6). The position is a distance (L1) away.
In the present invention, when water enters between the power generation cell (6) of the solar cell module (10) and the end of the substrate (1) due to exposure to a high humidity environment, the dielectric constant of that portion varies depending on the infiltrated water. . Therefore, electrodes are connected to both ends (first position (P1) and second position (P2)) of the region including the region where water enters, and the capacitance (first) between the electrodes before and after exposure to a high humidity environment. 1 electrostatic capacity and 2nd electrostatic capacity), and the change of the electrostatic capacity is calculated, so that the infiltration state of the water (ex. Inundation amount, inundation position, inundation range) can be estimated. Thereby, it is possible to evaluate the ease of water intrusion into the solar cell module in a non-destructive manner.

In the solar cell module evaluation method, the solar cell module (10) includes an end power generation cell separated from the power generation cell (6) by a groove (15) between the first side and the power generation cell (6). (6a) is further provided. The step (a) includes the step (a1) of attaching the first electrode (B1) to the first position (P1) and attaching the second electrode (B2) to the second position (P2). (D) The step comprises (d1) the second end (E2) on the power generation cell (6) side and the first in the end power generation cell (6a) based on the first capacitance and the second capacitance. A step of estimating a third capacitance between the end portion (E1) and (d2) based on the third capacitance, between the second end portion (E2) and the first end portion (E1). Evaluating a flooded state between the substrate (1) and the protective layer (2). The first capacitance and the second capacitance are capacitances between the first electrode (B1) and the second electrode (B2). The first distance (L1) is the capacitance between the transparent conductive layer (11) of the power generation cell (6) and the first electrode (B1) when measuring the first capacitance and the second capacitance. It is set to a size that can be ignored. The width (W1) in the first direction (Y) of the first electrode (B1) is equal to the transparent conductive layer (11) of the end power generation cell (6a) when measuring the first capacitance and the second capacitance. The capacitance between the first electrode (B1) and the first electrode (B1) is set to a negligible size.
In the present invention, by providing the first electrode (B1) so as to satisfy appropriate dimensions (first distance (L1), width (W1)), the values of the first capacitance and the second capacitance and the first capacitance are set. The value of 3 electrostatic capacity can be made substantially equal. Thereby, based on the first capacitance and the second capacitance, the third capacitance, that is, the second end (E2) and the second capacitance important for the formation of the closed electric circuit that causes the deterioration. It is possible to estimate the degree of water intrusion between one end (E1).

In the solar cell module evaluation method, the first distance (L1) is 1000 times or more the first width in the first direction (Y) between the power generation cell (6) and the end power generation cell (6a). It is. The width (W1) in the first direction (Y) of the first electrode (B1) is 1000 times or more the first width.
In the present invention, by setting the first distance (L1) and the width (W1) in this way, the values of the first capacitance and the second capacitance and the value of the third capacitance are substantially equal. be able to.

In the solar cell module evaluation method, the step (a) includes (a1) attaching the first electrode (B1) to the first position (P1) and attaching the second electrode (B2) to the second position (P2). Comprising steps. In step (d), (d1) a third capacitance between the first side (1a) and the first end (E1) is estimated based on the first capacitance and the second capacitance. And (d2) a submerged state between the substrate (1) and the protective layer (2) between the first side (1a) and the first end (E1) based on the third capacitance. And evaluating. The first capacitance and the second capacitance are capacitances between the first electrode (B1) and the second electrode (B2). The first distance (L1) is the capacitance between the transparent conductive layer (11) of the power generation cell (6) and the first electrode (B1) when measuring the first capacitance and the second capacitance. It is set to a size that can be ignored. The width (W1) in the first direction (Y) of the first electrode (B1) is determined between the first electrode (B1) and the second electrode (B2) when measuring the first capacitance and the second capacitance. The capacitance between the two is set to a value that can be ignored.
In the present invention, by providing the first electrode (B1) so as to satisfy appropriate dimensions (first distance (L1), width (W1)), the values of the first capacitance and the second capacitance and the first capacitance are set. The value of 3 electrostatic capacity can be made substantially equal. Thereby, based on the first capacitance and the second capacitance, the first capacitance (1a) and the first capacitance important for the formation of the third capacitance, that is, the closed electric circuit that causes deterioration. It is possible to estimate the degree of water intrusion between the ends (E1).

  In the solar cell module evaluation method, the first distance (L1) is 1000 times or more the second width in the first direction (Y) between the second electrode (B2) and the power generation cell (6). is there. The width (W1) in the first direction (Y) of the first electrode (B1) is 1000 times or more the second width.

In the solar cell module evaluation method, the step (d2) includes (d21) referring to a submergence amount table indicating a relationship between the capacitance and the amount of water submergence based on the third capacitance. Including a step of estimating a water immersion amount of the solar cell module (10).
In the present invention, the amount of water immersion can be easily estimated by using a water immersion amount table provided in advance by experiments, simulations, or the like.

In the solar cell module evaluation method, the step (d) further includes a step (d3) of estimating the lifetime of the solar cell module (10) based on the flooded state.
In the present invention, the degree of water intrusion into the solar cell module (10) can be estimated by estimating the change in the third capacitance before and after exposure to a high humidity environment. And the lifetime of a solar cell module (10) can be evaluated based on the grade of the permeation of the water.

In the solar cell module evaluation method, the step (d3) includes (d31) a life table indicating a relationship between the capacitance, the high humidity environment, and the life based on the third capacitance and the high humidity environment. With reference, the step of estimating the lifetime of the solar cell module (10) is included.
In the present invention, the amount of water immersion can be easily estimated by using a life table provided in advance by experiments, simulations, or the like.

In the solar cell module evaluation method described above, the step (b) includes a step (b1) of placing the solar cell module (10) in an environment change cycle including a high humidity environment.
In the present invention, by applying various environmental change cycles to the solar cell module (10), it is possible to more accurately estimate whether it is a non-defective product, weather resistance or life.

In the solar cell module evaluation method described above, the high humidity environment includes one of water or a chemical substance having a predetermined temperature and a high temperature and high humidity chamber having a predetermined temperature and humidity.
In the present invention, by exposing the solar cell module (10) to various environments, it is possible to more accurately estimate whether it is a non-defective product, weather resistance and life.

The solar cell module evaluation apparatus of the present invention includes a measuring instrument (41) and an information processing apparatus (42). The measuring instrument (41) includes a first terminal (C1) and a second terminal (C2), and is connected to the first electrode (B1) and the second terminal (C2) connected to the first terminal (C1). The electrostatic capacitance between the second electrode (B2) is measured. The information processing device (42) obtains an output from the measuring instrument (41) . The first electrode (B1) and the second electrode (B2) are in contact with the first position (P1) and the second position (P2) of the solar cell module (10) that is the evaluation target, respectively. The measuring instrument (41) measures the first capacitance between the first position (P1) and the second position (P2), and then after placing the solar cell module (10) in a high humidity environment, A second capacitance between the first position (P1) and the second position (P2) is measured. The information processing device (42) evaluates the flooded state of the solar cell module (10) based on the first capacitance and the second capacitance. The solar cell module (10) is provided apart from the substrate (1), the first side (1a) of the substrate (1), the transparent conductive layer (11), the photoelectric conversion layer (12), and the substrate (1). A power generation cell (6) including the back electrode layer (13) in this order, and a protective layer (2) covering the substrate (1) and the power generation cell (6) are provided. The second position (P2) is a position on the protective layer (2) in the vicinity of the first side (1a). The first position (P1) is on the substrate (1) opposite to the power generation cell (6) and is first from the first end (E1) on the first side (1a) side of the power generation cell (6). The position is a distance (L) away.

  In the solar cell module evaluation apparatus, the solar cell module (10) includes an end power generation cell separated from the power generation cell (6) by the groove (15) between the first side and the power generation cell (6). (6a) is further provided. The information processing device (42) includes a capacitance calculation unit (51), a storage unit (53), and an evaluation unit (52). Based on the first capacitance and the second capacitance, the capacitance calculation unit (51) and the second end (E2) on the power generation cell (6) side in the end power generation cell (6a) and the second capacitance The third capacitance between the first end (E1) is estimated. The storage unit (53) stores the third capacitance. Based on the third capacitance, the evaluation unit (52) is immersed in water between the substrate (1) and the protective layer (2) between the second end (E2) and the first end (E1). Assess the condition. The first capacitance and the second capacitance are capacitances between the first electrode (B1) and the second electrode (B2). The first distance (L1) is the capacitance between the transparent conductive layer (11) of the power generation cell (6) and the first electrode (B1) when measuring the first capacitance and the second capacitance. It is set to a size that can be ignored. The width (W1) in the first direction (Y) of the first electrode (B1) is equal to the transparent conductive layer (11) of the end power generation cell (6a) when measuring the first capacitance and the second capacitance. The capacitance between the first electrode (B1) and the first electrode (B1) is set to a negligible size.

  In the solar cell module evaluation apparatus, the first distance (L1) is 1000 times or more the first width in the first direction (Y) between the power generation cell (6) and the end power generation cell (6a). It is. The width (W1) in the first direction (Y) of the first electrode (B1) is 1000 times or more the first width.

  In the solar cell module evaluation apparatus, the information processing device (42) includes a capacitance calculation unit (51), a storage unit (53), and an evaluation unit (52). The capacitance calculating unit (51) calculates a third capacitance between the first side (1a) and the first end (E1) based on the first capacitance and the second capacitance. estimate. The storage unit (53) stores the third capacitance. Based on the third capacitance, the evaluation unit (52) is in a flooded state between the substrate (1) and the protective layer (2) between the first side (1a) and the first end (E1). To evaluate. The first capacitance and the second capacitance are capacitances between the first electrode (B1) and the second electrode (B2). The first distance (L1) is the capacitance between the transparent conductive layer (11) of the power generation cell (6) and the first electrode (B1) when measuring the first capacitance and the second capacitance. It is set to a size that can be ignored. The width (W1) in the first direction (Y) of the first electrode (B1) is determined between the first electrode (B1) and the second electrode (B2) when measuring the first capacitance and the second capacitance. The capacitance between the two is set to a value that can be ignored.

  In the solar cell module evaluation apparatus, the first distance (L1) is 1000 times or more the second width in the first direction (Y) between the second electrode (B2) and the power generation cell (6). is there. The width (W1) in the first direction (Y) of the first electrode (B1) is 1000 times or more the second width.

  In the solar cell module evaluation apparatus, the storage unit (53) stores an inundation amount table indicating a relationship between the capacitance and the inundation amount of water. The evaluation unit (52) estimates the water immersion amount of the solar cell module (10) with reference to the water immersion amount table based on the third capacitance.

  In the solar cell module evaluation apparatus, the evaluation unit (52) further estimates the lifetime of the solar cell module (10) based on the flooded state.

  In the solar cell module evaluation apparatus, the storage unit (53) stores a life table indicating a relationship among the capacitance, the high humidity environment, and the life. The evaluation unit (52) estimates the lifetime of the solar cell module (10) with reference to the lifetime table based on the third capacitance and the high humidity environment.

  According to the present invention, it is possible to measure the invasion of a small amount of water at a stage before the deterioration of the solar cell module occurs. The lifetime of the solar cell module can be evaluated.

  Hereinafter, embodiments of a solar cell module evaluation method and a solar cell module evaluation apparatus according to the present invention will be described with reference to the accompanying drawings.

  First, the structure of the solar cell module which is the evaluation object of the solar cell module evaluation method and evaluation apparatus of the present invention will be described with reference to the accompanying drawings. FIG. 4 is a top view showing the configuration of the solar cell module to be evaluated in the embodiment of the solar cell module evaluation method and evaluation apparatus of the present invention. The solar cell module 10 includes a substrate 1 and a power generation cell 6 provided on the substrate 1. Here, for ease of explanation, a protective film 2 and a waterproof sheet 3 described later provided on these are omitted.

  The substrate 1 includes a first side 1a, a second side 1b facing the first side 1a, a third side 1c between the first side 1a and the second side 1b, and a third side 1c facing the third side 1c. 4 sides 1d. The substrate 1 has translucency, and for example, glass is suitable.

  The power generation cell 6 is provided inside the peripheral region 14 without a thin film on the surface of the substrate 1. The power generation cell 6 includes a plurality of single cells 7. The plurality of single cells 7 are aligned in the X direction and connected in series to each other. The single cell 7 has a strip shape extending in the Y direction. The power generation cell 6 further includes end power generation cells 6a and 6b. The end power generation cell 6a is separated from the power generation cell 6 by the X-direction insulating groove 15a parallel to the first side 1a between the first side 1a and the power generation cell 6. The end power generation cell 6b is separated from the power generation cell 6 between the second side 1b and the power generation cell 6 by an X-direction insulating groove 15b parallel to the second side 1b.

  The power generation cell 6 is, for example, a silicon-based thin film solar cell. Here, silicon-based is a general term for materials containing silicon such as silicon (Si), silicon carbide (SiC), and silicon germanium (SiGe). The silicon-based thin film solar cell represents an amorphous silicon-based, microcrystalline silicon-based, solar cell including a tandem type in which amorphous silicon-based and microcrystalline silicon-based layers are stacked. However, the microcrystalline silicon system means a silicon system other than an amorphous silicon system (amorphous silicon system), and includes a polycrystalline silicon system and a crystalline silicon system containing an amorphous material.

  The X direction insulating groove 15 a and the X direction insulating groove 15 b extend from the back electrode layer 13 which is the surface of the plurality of single cells 7 to the surface of the substrate 1 and reach the surface of the substrate 1 in the depth direction. However, it is preferable not to extend into the substrate 1 in order to ensure the strength of the substrate 1. On the other hand, the length direction extends in the X direction. One end extends to the vicinity of the third side 1c, and the other end extends to the vicinity of the fourth side 1d. Both ends do not reach the end of the substrate 1. The width of the X direction insulating groove 15 is, for example, 50 to 100 μm.

  FIG. 5: is sectional drawing which shows the structure of the solar cell module used as the evaluation object in embodiment of the evaluation method and evaluation apparatus of the solar cell module of this invention. The A section of the XX cross section of FIG. 4 is shown. As described above, the solar cell module 10 includes the substrate 1, the power generation cell 6 provided on the substrate 1, the protective film 2 provided to cover the peripheral region 14 of the substrate 1 and the power generation cell 6, and protection A waterproof sheet 3 provided on the membrane 2 is provided.

  The waterproof sheet 3 is provided so as to cover the protective film 2 on the power generation cell 6. A sheet having a three-layer structure of PET (polyethylene terephthalate) sheet / AL foil / PET sheet is exemplified. The protective film 102 is provided so as to cover the power generation cell 6 and the peripheral region 14 on the surface of the substrate 1. It is exemplified by EVA (ethylene vinyl acetate copolymer). The film thickness is 30-50 μm. Each of the plurality of single cells 7 is provided on the substrate 1, arranged in the X direction along the first side 1 a, and connected in series to each other. The single cell 7 includes a transparent conductive layer 11, a photoelectric conversion layer 12, and a back electrode layer 13.

  The transparent conductive layer 11 is formed on the substrate 1 and is divided by a groove 15 extending in the X direction so as to correspond to each of the plurality of strip-shaped single cells 7. The film thickness is 500 to 800 nm. The groove 17 extends from the surface of the transparent conductive layer 11 to the surface of the substrate 1 in the depth direction. It extends to the vicinity of the first side 1 a and the second side 1 b in the length direction, and does not reach the end of the substrate 1. The width of the groove 17 is, for example, 10 to 50 μm. The photoelectric conversion layer 12 constitutes a tandem type or triple type solar cell in which a p-layer, an i-layer, and an n-layer of thin film silicon are laminated and a plurality of the laminated layers are laminated. The photoelectric conversion layer 12 is provided on the transparent conductive layer 11 and is divided so as to correspond to each of the plurality of single cells 7 by a groove 18 extending in the Y direction in the vicinity of the groove 17. The groove 18 extends from the surface of the photoelectric conversion layer 12 to the surface of the transparent conductive layer 11 in the depth direction. The back electrode layer 13 is provided on the photoelectric conversion layer 12 and is divided so as to correspond to each of the plurality of single cells 7 by a groove 19 extending in the Y direction in the vicinity of the groove 18. The groove 19 extends from the surface of the back electrode layer 13 to the surface of the photoelectric conversion layer 12 in the depth direction.

  FIG. 6 is another cross-sectional view showing the configuration of the solar cell module to be evaluated in the embodiment of the solar cell module evaluation method and evaluation apparatus of the present invention. 5 shows a portion A of the YY cross section of FIG. As described above, the solar cell module 10 further includes the end power generation cells 6a and the end power generation cells 6b (not shown in this drawing).

  The waterproof sheet 3 is provided so as to cover not only the power generation cell 6 but also the protective film 2 on the end power generation cell 6a and the end power generation cell 6b. The X-direction insulating groove 15a is provided between the end E1 of the power generation cell 6 and the end E2 of the end power generation cell 6a. Similarly, although not shown, the X-direction insulating groove 15b is provided between the end of the power generation cell 6 and the end of the end power generation cell 6b.

  Next, the configuration of the embodiment of the solar cell module evaluation apparatus of the present invention will be described. FIG. 7 is a schematic diagram showing the configuration of the embodiment of the solar cell module evaluation apparatus of the present invention. Here, about the solar cell module 10, the A part of the YY cross section of FIG. 4 is shown similarly to FIG. 6, and water 31 and 32 has entered between the protective film 2 and the substrate 1 under the influence of water. Is shown. The water 31 is water between the protective film 2 and the substrate 1 between the end E1 of the power generation cell 6 and one end E2 of the end power generation cell 6a (X-direction insulating groove 15a). The water 32 is water between the protective film 2 and the substrate 1 between the other end E3 of the end power generation cell 6a and the first side 1a.

  In the solar cell module evaluation method of the present invention, the inundation status of the water 31 is evaluated using an evaluation device. When water enters between the end E1 of the power generation cell 6 and the end E2 of the end power generation cell 6a (X-direction insulating groove 15a), a closed electric circuit is formed as described in FIG. This is because the module 10 is seriously affected. In this case, the measurement target is the capacitance C2 between the end E1 of the power generation cell 6 and the end E2 of the end power generation cell 6a.

The solar cell module evaluation apparatus 40 includes an AC characteristic measuring instrument 41 and an information processing apparatus 42.
The AC characteristic measuring instrument 41 includes a first terminal D1 and a second terminal D2, and a static electricity between the first electrode B1 connected to the first terminal D1 and the second electrode B2 connected to the second terminal D2. Measure the capacitance. Here, the first electrode B1 and the second electrode B2 are brought into contact with the first position P1 and the second position P2 of the solar cell module 10 that is an evaluation object, respectively, at the time of measurement.

  However, the second position P2 is a position on the protective layer 2 in the vicinity of the first side 1a. The first position P1 is a position on the substrate 1 opposite to the power generation cell 6 and a distance L1 from the end E1 of the power generation cell 6 on the first side 1a side. As will be described later, the distance L1 is set to such a value that the capacitance between the transparent conductive layer 11 of the power generation cell 6 and the first electrode B1 can be ignored. The width W1 in the Y direction of the first electrode B1 is set to a size such that the capacitance between the transparent conductive layer 11 of the end power generation cell 6a and the first electrode B1 can be ignored. For example, the distance L1 is 1000 times or more the width L2 in the Y direction of the measurement target (C2), and the width W1 in the Y direction of the first electrode B1 is 1000 times or more of the width L2 of the measurement target (C2). .

  The information processing apparatus 42 is exemplified by a personal computer and is connected to the AC characteristic measuring instrument 41 so as to be able to communicate data. Based on the measurement result of the AC characteristic measuring instrument 41, the flooded state of the solar cell module 10 is evaluated. The information processing apparatus 42 includes a capacitance calculation unit 51 and a life evaluation unit 52 as computer programs, and a storage unit 53 as a storage device such as a hard disk or a memory. The capacitance calculation unit 51 and the life evaluation unit 52 are stored in a hard disk as the storage unit 53, and are expanded in a memory as the storage unit 53 during operation, and are executed by a CPU (central processing unit).

The capacitance calculation unit 51 estimates the capacitance of the measurement target based on the measurement result of the AC characteristic measuring instrument 41.
For example, the capacitance C2 is estimated. The storage unit 53 stores the estimated capacitance. In addition, data (table) necessary for the execution of the capacitance calculation unit 51 and the life evaluation unit 52 is stored. The life evaluation unit 52 evaluates the flooded state of the measurement target part based on the estimated capacitance. For example, the water immersion state between the substrate 1 and the protective layer 2 between the end E2 and the end E1 (position of the capacitance C2) is evaluated. The life evaluation unit 52 further estimates the life of the solar cell module 10 based on the evaluated flooded state.

  FIG. 8: is the schematic plan view and schematic sectional drawing which show the structure of embodiment of the evaluation apparatus of the solar cell module of this invention. Here, the AC characteristic measuring instrument 41, the information processing apparatus 42, its wiring, and the waterproof sheet 3 are omitted. The positional relationship among the first electrode B1, the second electrode B2, the power generation cell 6, the end power generation cell 6a, the end E1, and the end E2 is shown. In the figure, in order to evaluate the measurement target (C2) between the leftmost power generation cell 6 and the end power generation cell 6a, the first electrode B1 is located at a position corresponding to a wide area including the power generation cell 6. It becomes the electrode of the provided large area. On the other hand, the second electrode B2 is a small-area electrode provided at a position corresponding to the side of the end power generation cell 6a. Then, by shifting the position of the second electrode B2 to the right and shifting the position of the first electrode B1 to the right as necessary, the measurement target between the other power generation cells 6 and the end power generation cells 6a. It can measure similarly about (C2). Thereby, in addition to the amount of flooding, the flooding position and flooding range can be known.

Next, the measurement principle of the capacitance C2 in the solar cell module evaluation method of the present invention will be described.
As shown in FIG. 7, the equivalent circuit between the first electrode B1 and the second electrode B2 is composed of a capacitance C3, a resistor R1, a capacitance C2, a capacitance C1, and a capacitance C4. The The capacitance C3 is formed by the transparent conductive layer 11 of the power generation cell 6 and the first electrode B1, and the substrate 1 is a dielectric. The resistor R <b> 1 is formed of the transparent conductive layer 11. The electrostatic capacitance C2 is formed by the transparent conductive layer 11 of the power generation cell 6 and the transparent conductive layer 11 of the end power generation cell 6a, and the water 31 and the protective film 2 are dielectrics. The electrostatic capacitance C1 is formed by the transparent conductive layer 11 of the end power generation cell 6a and the second electrode B2, and the protective film 2 is a main dielectric. The capacitance C4 is formed by the transparent conductive layer 11 of the end power generation cell 6a and the first electrode B1, and the substrate 1 is a dielectric.

  Here, when the solar cell module 10 is exposed to a high humidity atmosphere and the water 31 increases, the influence of the intrusion water 31 appears in the capacitance C2 as a change in dielectric constant. Therefore, the amount of water 31 immersed can be estimated by measuring the change in capacitance C2 before and after exposure to a high humidity atmosphere (change in capacitance C2 over time).

If the capacitance between the first electrode B1 and the second electrode B2 is C and the capacitance C4 can be ignored, the following equation is established.
1 / C = 1 / C1 + 1 / C2 + 1 / C3 (1)
Therefore, if C1 and C3 are sufficiently large compared to C2 (10 ³ order or more),
1 / C = 1 / C2 (2)
Can be considered. In general, since C = εS / d holds, the S / d of C1 and C3 should be sufficiently larger than the S / d of C2 (10 ³ order or more).

In C2, the distance d (width L2) is on the order of 10 ¹ μm. Area S (the thickness of the X-direction width × transparent conductive layer 11 of the single cell 7) is on the order of 10 ³ μm × 10 ⁰ μm. Therefore, S / d is on the order of 10 ² μm.

In C3, in order for C3 to have a size of 10 ³ orders or more as compared with C2, S / d needs to be on the order of 10 ² μm (C2) × 10 ³ = 10 ⁵ μm. Since the distance d (thickness of the substrate 1) of C3 is on the order of 10 ³ μm, the area S of C3 is on the order of 10 ³ μm (distance d) × 10 ⁵ μm = 10 ⁸ μm ² = 10 ² mm ² Become. Therefore, C3, that is, the area S of the first electrode B1 is on the order of 10 ² mm ² , and if the first electrode B1 is regarded as a rectangle, the width W1 corresponding to one side thereof is about 10 ¹ mm. That is, the width W1 in the Y direction of the first electrode B1 may be 1000 times (10 ³ times) or more of the width L2 of C2.

Similarly, in C1, in order for C1 to have a magnitude of 10 ³ orders or more as compared with C2, S / d needs to be on the order of 10 ⁵ μm. Since the distance C1 d (thickness of the protective layer 2) is of the order of 10 ¹ [mu] m, the area S of C1 is, 10 ¹ [mu] m (distance d) × 10 of ^{5 μm = 10 6 μm 2 =} 10 0 mm 2 It becomes an order. Therefore, since the area S of the C1 or second electrode B2 is a ¹⁰ 0 mm ² orders, is regarded a second electrode B2 and rectangular, one side is about ¹⁰ 0 mm approximately. That is, the width of the second electrode B2, it is sufficient to the 100 times the width L2 of C2 (10 ² times) or more. On the other hand, if the second electrode B2 is too large, the direct capacitance (not shown in FIG. 7) between the second electrode B2 and the first electrode B1 may become a problem. It is preferable to make it as small as possible. From the above, one side is about ¹⁰ 0 mm approximately.

On the other hand, in order to ignore C4 in the expression (1), C4 parallel to C2 is sufficiently smaller than C2 (10 ⁻³ order or less), that is, the S / d of C4 is changed to the S / d of C2. It may be sufficiently smaller than d (10 ⁻³ order or less). In C4, in order for C4 to have a magnitude of 10 ⁻³ order or less compared to C2, S / d needs to be on the order of 10 ² μm (C2) × 10 ⁻³ = 10 ⁻¹ μm. . C4 area S (end power generation cell 6a side of the thickness of the X-direction width × transparent conductive layer 11 of the single cell 7) is on the order of 10 ⁴ μm × 10 ⁰ μm. Therefore, the distance d of C4 becomes ^{(10 4 μm × 10 0 μm} ) / (10 -1 μm) = 10 5 μm = 10 2 mm approximately. That is, the sum of the width L2 and the distance L1 is required to be approximately 10 ² mm or more. Since the width L2 is on the order of 10 ¹ μm and can be ignored, the distance L1 is about 10 ² mm or more. That is, the distance L1 may be 1000 times or more the width L2 of C2.

From the above, in C3, the width W1 in the Y direction in the first electrode B1 is 1000 times the width L2 of C2 (10 ³ times) than in the C1, 100 times the width L2 of the width of the second electrode B2 C2 ( and 10 ^twice) or more, in C4, if the distance L1 between 1000 times or more the width L2 of C2, so that the equation (2) is satisfied in the equivalent circuit of FIG.

  Next, the principle of the solar cell module evaluation method of the present invention using the capacitance C2 will be described. First, how the capacitance C2 changes when the solar cell module 10 is affected by water will be described. FIG. 9 is a graph showing the relationship between the test time and the capacitance when a water immersion test (high humidity environment test: described later) is performed on the solar cell module 10. The vertical axis represents the value of the capacitance C2, and the horizontal axis represents the test time t of the water immersion test. The solar cell module 10 shows a value of C2 = C2 (0) before the water immersion test (origin). Then, after the immersion test (t = t0), the capacitance of the electrostatic capacitance C2 changes with the change of the dielectric constant by the water aggregated inside the waterproof sheet 3 of the solar cell module 10. At this time, if the solar cell module 10 is a non-defective product, after the water immersion test (t = t0), the value of C2 = C2 (1) (> C2 (0)) is shown as shown by the curve Q1. C2 slightly increases because the protective film 2 slightly absorbs water, and is a value determined from the conditions of the water immersion test and the physical properties (water content) of the protective film 2. On the other hand, if the solar cell module 10 is defective, water enters between the substrate 1 and the protective film 2 after the water immersion test (t = t0), so that C2 further increases, as shown by curves Q2 and Q3. Shows values such as C2 = C2 (2) (> C2 (1)) and C2 (3) (> C2 (2)).

  Here, although the value of C2 (0) is slightly different depending on the individual solar cell module 10, the difference Δ = C2 (1) −C2 (0) (, C2 (2) −C2 (0)) is substantially equal. Therefore, if the relationship between the good and defective products and the difference Δ (stored in the storage unit 53 and for each structure of the solar cell module) is obtained in advance by simulation or experiment, C2 before and after the water immersion test is measured to obtain the difference Δ. Thus, it is possible to evaluate whether the solar cell module 10 is a good product or a defective product. Furthermore, it is possible to classify the levels of the solar cell modules 10 based on the magnitude of the difference Δ. In that case, the relationship between the level and the difference Δ is stored in the storage unit 53 in advance.

  In addition, if a relationship between the amount of moisture (immersion amount) infiltrated between the protective film 2 and the substrate 1 and the difference Δ (stored in the storage unit 53 and for each structure of the solar cell module) is obtained in advance by simulation or experiment. By measuring C2 before and after the water immersion test and determining the difference Δ, the amount of water that has entered the solar cell module 10 can be estimated.

Further, the principle of calculating the lifetime of the solar cell module in the solar cell module evaluation method of the present invention using the capacitance C2 will be described. As a method for calculating the lifetime from the value of C2, the following method can be considered. First, a table in which the conditions of the immersion test, the magnitude of the difference Δ after the immersion test and the remaining lifetime are associated with each other is obtained in advance by experiment or simulation (stored in the storage unit 53 and for each structure of the solar cell module). As an example of table data,
Test conditions: humidity 90%, temperature 80 ° C., time 2 hours; difference Δ: 10 pF; life: 20 years,
Test conditions: humidity 90%, temperature 80 ° C., time 2 hours; difference Δ: 30 pF; life: 15 years,
Test conditions: humidity 90%, temperature 80 ° C., time 2 hours; difference Δ: 50 pF; life: 10 years,
Etc. Next, C2 before and after the water immersion test is measured to obtain a difference Δ, and the lifetime is calculated based on the test condition, the difference Δ, and the table. The intermediate value of the data is obtained by extrapolation (interpolation).

  As described above, in the solar cell module evaluation method of the present invention, the change and the life of the solar cell module are evaluated by measuring the change in the capacitance C2 using the solar cell module evaluation apparatus of the present invention. It becomes possible.

  Next, an embodiment of the solar cell module evaluation method of the present invention will be described. Here, a method for evaluating the solar cell module 10 described with reference to FIGS. 4 to 6 using the solar cell module evaluation apparatus described with reference to FIG. 7 will be described. FIG. 10 is a flowchart showing an embodiment of the solar cell module evaluation method of the present invention.

(1) Step S01: A first capacitance between the first position P1 and the second position P2 of the solar cell module 10 is measured.
Referring to FIG. 7, solar cell module 10 not affected by water is prepared, and first electrode B1 is attached to first position P1 and second electrode B2 is attached to second position P2. The first position P1 is a position on the substrate 1 on the opposite side of the power generation cell 6 and a first distance L away from the first end E1 on the first side 1a side of the power generation cell 6. The second position P2 is a position on the protective layer 2 in the vicinity of the first side 1a. The distance L1 is 1000 times or more of the width L2 in the Y direction in the measurement target C2. The width W1 in the Y direction of the first electrode B1 is 1000 times or more the width L2 of the measurement target C2. The width of the second electrode B2 is about 10 ⁰ mm on one side. By doing in this way, among the equivalent circuit shown in FIG. 7, C1, C3, C4 can be disregarded, and the above equation (2) can be used.
The AC characteristic measuring instrument 41 measures the capacitance between the first position P1 and the second position P2 via the first terminal D1 and the second terminal D2, and outputs it to the information processing apparatus 42. The electrostatic capacity calculation unit 51 of the information processing device 42 calculates the first electrostatic capacity as C2 based on the measured electrostatic capacity and the equation (2). The storage unit 53 stores the value of the first capacitance. However, the measured capacitance is substituted for C in equation (2). The first capacitance is C2 (0), which is a value when not affected by water. The capacitance calculating unit 51 may perform this part of the operation in step S03.
(2) Step S02:
The solar cell module 10 is subjected to a water immersion test (high humidity environment test).
After measuring the first capacitance and removing each electrode, the solar cell module 10 is subjected to a water immersion test. The immersion test (high humidity environment test) is a test in which the solar cell module 10 is exposed to a high humidity environment. The conditions for the immersion test (high humidity environment) are, for example, a humidity of 90%, a temperature of 80 ° C., and an exposure time of 2 hours. However, the conditions of the immersion test (high humidity environment) are not limited to this example. For example, it is used for the test described in JIS C 8938 “Environmental test method and durability test method of amorphous solar cell module”. The conditions of the test related to water resistance (example: temperature / humidity cycle test, salt spray test, waterproof test, moisture resistance test) can be used. Further, immersion in a chemical substance (eg, an acidic substance (assuming acidic rain or the like) that may cause deterioration) and an alkaline substance (assuming bird droppings) may be performed.
(3) Step S03
After the water immersion test, the second capacitance between the first position P1 and the second position P2 of the solar cell module 10 is measured.
Similarly to step S01, referring to FIG. 7, for solar cell module 10 after the water immersion test, first electrode B1 is attached to first position P1, and second electrode B2 is attached to second position P2. The first position P1, the second position P2, the distance L1, the width W1, and the width of the second electrode B2 are the same as in step S01, and the above equation (2) can be used.
The AC characteristic measuring instrument 41 again measures the electric capacity between the first position P1 and the second position P2 via the first terminal D1 and the second terminal D2, and outputs it to the information processing apparatus 42. The capacitance calculation unit 51 of the information processing device 42 calculates the second capacitance as C2 based on the measured capacitance and the equation (2). The storage unit 53 stores the value of the second capacitance. However, the measured capacitance is substituted for C in equation (2). The solar cell module 10 is affected by water due to being exposed to a high humidity environment (step S02). Therefore, in the solar cell module 10, there is a possibility that the protective film 2 absorbs water or water 31 or water 32 exists as shown in FIG. That is, the second capacitance is a value such as C2 (1), C2 (2), or C2 (3) that is a value when affected by water.
(4) Step S04
Based on the first capacitance and the second capacitance, the flooded state of the solar cell module 10 is evaluated (deterioration after outdoor exposure is estimated).
Based on the first capacitance and the second capacitance, the life evaluation unit 52 of the information processing device 42 determines the difference Δ (first capacitance−second capacitance) between the capacitance C2 before and after the water immersion test. ). Then, the solar cell module 10 can be divided into a non-defective product and a defective product based on the relationship between the non-defective product and the defective product stored in the storage unit 53 and the difference Δ. Alternatively, the solar cell module 10 can be classified into levels based on the relationship between the level stored in the storage unit 53 and the difference Δ.
In addition, the life evaluation unit 52 of the information processing device 42 protects based on the estimated difference Δ and a table that associates the amount of water stored in the storage unit 53 with the magnitude of the difference Δ after the water immersion test. The amount of moisture that has entered between the film 2 and the substrate 1 is estimated.
In addition, the life evaluation unit 52 of the information processing apparatus 42 includes the estimated difference Δ, the immersion test condition, the condition of the immersion test stored in the storage unit 53, the magnitude of the difference Δ after the immersion test, and the remaining lifetime. The lifetime of the solar cell module 10 is estimated based on the table in which

  By the solar cell module evaluation method of the present invention using the solar cell module evaluation apparatus of the present invention described above, the solar cell module is classified into non-defective products and defective products, leveled, and the amount of water immersion is estimated. It is possible to estimate the lifespan.

  FIG. 11 is a graph showing the results of comparing the solar cell module evaluation method of the present invention with a conventional evaluation method using a leakage current. Fig.11 (a) shows the result of the evaluation method of the solar cell module of this invention. The vertical axis (linear scale) indicates the increase in capacitance, that is, the difference Δ in the capacitance C2, and the horizontal axis indicates the environmental temperature, that is, the temperature of the immersion test. Circle marks indicate immersion in pure water in a water immersion test (humidity 100%), square marks indicate immersion in sulfuric acid aqueous solution (pH 1.3), and triangle marks indicate immersion in aqueous ammonia (pH 11). It shows that. However, immersion in sulfuric acid aqueous solution and ammonia water is only 25 ° C. FIG. 11B shows a conventional evaluation method using a leakage current. The vertical axis (log scale) shows the increase in leakage current, and the horizontal axis shows the environmental temperature of the water immersion test. Circle marks, square marks, and triangle marks are the same as in FIG. 11A, and immersion in sulfuric acid aqueous solution and ammonia water is only 25 ° C.

  In the solar cell module evaluation method of the present invention, there was no change at 25 ° C., but the capacitance C2 tended to increase as the temperature increased to 60 ° C. and 80 ° C. That is, as the temperature increases, the amount of moisture entering between the protective film 2 and the substrate 1 increases. On the other hand, the conventional evaluation method using the leakage current does not change at 25 ° C., but the leakage current tends to increase as the temperature increases to 60 ° C. and 80 ° C. It was. When both graphs are compared, there is a correlation between the change in the capacitance C2 estimated by the solar cell module evaluation method of the present invention, that is, the amount of water immersion and the leakage current in the conventional evaluation method (JIS test) using leakage current. I found out. That is, it can be seen that the solar cell module evaluation method of the present invention can perform the same evaluation as the method using the leakage current.

  Further, since the leakage current and the film deformation mass are in a proportional relationship, it is possible to estimate the period (life) in which the film deformation mass reaches the limit. Similarly, the capacitance in the evaluation direction of the solar cell module according to the present invention and the amount of water immersion are substantially proportional, and the amount of water immersion and the film variable mass are generally proportional, so the film variable mass reaches the limit. The period (lifetime) can be estimated. That is, also in the evaluation direction of the solar cell module in the present invention, the lifetime of the solar cell module can be estimated by obtaining the capacitance.

  In the present invention, by measuring the capacitance between two electrodes provided at a predetermined position of the solar cell module before and after the water immersion test, water that has entered between the protective film and the substrate is detected, and the amount of the water is detected. Can be estimated. Thereby, it becomes possible to divide a solar cell module into a non-defective product and a defective product, and to predict the lifetime.

  In addition, although the said embodiment demonstrated the case where the edge part power generation cell 6a exists, this invention is not limited to it. FIG. 12 is a schematic diagram showing the configuration of the embodiment of the solar cell module evaluation apparatus of the present invention. The solar cell module evaluation device 40 is the same as that in FIG. 7, but differs from the case in FIG. 7 in that the end power generation cell 6 a is not present in the structure of the solar cell module 10 to be evaluated. The water 33 is water between the protective film 2 and the substrate 1 between the end E1 of the power generation cell 6 and the first side 1a.

  In the case of FIG. 12, in the solar cell module evaluation method of the present invention, the inundation status of the water 33 is evaluated using an evaluation device. This is because when water enters between the end E1 of the power generation cell 6 and the first side 1a, a closed electric circuit is formed as described with reference to FIG. In this case, the measurement target is the capacitance C5 between the end E1 of the power generation cell 6 and the end E2 of the end power generation cell 6a.

  The solar cell module evaluation device 40 is the same as that in the case of FIG.

Next, the measurement principle of the capacitance C5 in the solar cell module evaluation method of the present invention will be described.
As shown in FIG. 12, the equivalent circuit between the first electrode B1 and the second electrode B2 is composed of a capacitance C3, a resistor R1, a capacitance C2, and a capacitance C7. The capacitance C3 is formed by the transparent conductive layer 11 of the power generation cell 6 and the first electrode B1, and the substrate 1 is a dielectric. The resistor R <b> 1 is formed of the transparent conductive layer 11. The capacitance C2 is formed by the transparent conductive layer 11 of the power generation cell 6 and the second electrode B2, and water 33 is a main dielectric. The capacitance C7 is formed by the second electrode B2 and the first electrode B1, and the substrate 1 is a main dielectric.

  Here, when the solar cell module 10 is exposed to a high humidity atmosphere and the water 33 increases, the influence of the intrusion water 33 appears in the capacitance C2 as a change in dielectric constant. Therefore, the amount of water 33 immersed can be estimated by measuring the change in capacitance C2 before and after exposure to a high humidity atmosphere (change in capacitance C2 over time).

Here, if the electrostatic capacity between the first electrode B1 and the second electrode B2 is C and the electrostatic capacity C7 can be ignored, the following expression is established.
1 / C = 1 / C2 + 1 / C3 (1)
Therefore, if C3 is sufficiently larger than C2 (10 ³ order or more),
1 / C = 1 / C2 (2)
Can be considered. Generally, since C = εS / d holds, the S / d of C3 may be sufficiently larger than the S / d of C2 (10 ³ order or more).

The 2nd electrode B2 is attached to the position of several mm from the edge part E1 of the electric power generation cell 6, and the shape is made into the rectangle whose side is several mm. In C2, the distance d (width L3) between the second electrode B2 and the end E1 of the power generation cell 6 is on the order of 10 ⁰ mm. The area S (area of the second electrode B1) is on the order of 10 ⁰ mm × 10 ⁰ mm. Therefore, the order of S / d is ¹⁰ 0 mm.

In C3, in order for C3 to have a size on the order of 10 ³ or more compared to C2, S / d needs to be on the order of 10 ⁰ mm (C2) × 10 ³ = 10 ³ mm. Since C3 distance d (thickness of the substrate 1) is of the order of ¹⁰ 0 mm, the area S of the C3 becomes a ¹⁰ 3 mm (distance ^{d) × 10 3 mm = 10} 6 mm 2 orders. Therefore, C3, that is, the area S of the first electrode B1 is on the order of 10 ⁶ mm ² , and if the first electrode B1 is regarded as a rectangle, the width W1 corresponding to one side thereof is about 10 ³ mm. That is, the width W1 in the Y direction of the first electrode B1 may be set to 1000 times (10 ³ times) or more of the width L3 of C2.

On the other hand, in order to ignore C7 in equation (1), C7 parallel to C2 is sufficiently smaller than C2 (10 ⁻³ order or less), that is, the S / d of C7 is changed to the S / d of C2. It may be sufficiently smaller than d (10 ⁻³ order or less). In C7, in order to have a C7 is compared to ^{10 -3} order or less in size to C2, it is necessary S / d is on the order of ^{10 0 mm (C2) × 10} -3 = 10 -3 mm . The area S of C7 (the area of the second electrode B2) is on the order of 10 ⁰ mm × 10 ⁰ mm. Therefore, the distance d of C4 is about (10 ⁰ mm × 10 ⁰ mm) / (10 ⁻³ mm) = 10 ³ mm. That is, the sum of the width L3 and the distance L1 is required to be approximately 10 ³ mm or more. Since the width L3 is on the order of 10 ⁰ mm and can be ignored, the distance L1 is approximately 10 ³ mm or more. That is, the distance L1 may be 1000 times or more the width L3 of C2.

From the above, in the C3, 1000 times the width L2 of the width W1 in the Y direction in the first electrode B1 C2 and (10 ³ times) than in C7, a distance L1 if 1000 or more times the width L2 of the C2, In the equivalent circuit of FIG. 7, the above equation (2) is established.

  The principle of the solar cell module evaluation method of the present invention (including FIG. 9) using the capacitance C2 and the embodiment of the solar cell module evaluation method of the present invention (including FIG. 10) are shown in FIG. Since this is the same as the case, the description thereof is omitted. In this case, the same effect as in FIG. 7 can be obtained.

  In the above embodiment, only the capacitance of the capacitance C2 is examined, but the present invention is not limited to this. For example, the AC characteristic measuring instrument 41 can evaluate the inundation situation using the frequency characteristics (capacitance and pure resistance) of the capacitance C2. For example, the relationship between the inundation status (inundation amount, inundation position, inundation range, etc.) and frequency characteristics (capacitance and pure resistance) is obtained in advance through experiments or simulations (stored in the storage unit 53) and measured. The situation of flooding can be evaluated by comparison with values. Thereby, the situation of flooding can be evaluated in more detail.

  In the evaluation method of the present invention, the ingress of water can be evaluated even before the infiltrated water (water vapor) forms a leak circuit, that is, before the solar cell module is altered. Therefore, alterations that may occur after long-term outdoor exposure can be detected with high sensitivity. That is, the quality test can be performed before the solar cell module is deteriorated. And the lifetime of the solar cell module can be evaluated by the evaluation.

  In the evaluation method of the present invention, evaluation can be performed by a non-destructive method using AC characteristics without destroying the solar cell module. That is, the solar cell module after evaluation can be used. Thereby, it is possible to reduce the cost of the deterioration test.

FIG. 1 is a diagram showing a conventional solar cell module. FIG. 2 is a conceptual diagram illustrating the deterioration mechanism. FIG. 3 is a conceptual diagram showing an outline of a test method defined in JIS. FIG. 4 is a top view showing the configuration of the solar cell module to be evaluated in the embodiment of the solar cell module evaluation method and evaluation apparatus of the present invention. FIG. 5: is sectional drawing which shows the structure of the solar cell module used as the evaluation object in embodiment of the evaluation method and evaluation apparatus of the solar cell module of this invention. FIG. 6 is another cross-sectional view showing the configuration of the solar cell module to be evaluated in the embodiment of the solar cell module evaluation method and evaluation apparatus of the present invention. FIG. 7 is a schematic diagram showing the configuration of the embodiment of the solar cell module evaluation apparatus of the present invention. FIG. 8: is the schematic plan view and schematic sectional drawing which show the structure of embodiment of the evaluation apparatus of the solar cell module of this invention. FIG. 9 is a graph showing the relationship between the test time and the capacitance when a water immersion test is performed on the solar cell module. FIG. 10 is a flowchart showing an embodiment of the solar cell module evaluation method of the present invention. FIG. 11 is a graph showing the results of comparing the solar cell module evaluation method of the present invention with a conventional evaluation method using a leakage current. FIG. 12 is a schematic diagram showing the configuration of the embodiment of the solar cell module evaluation apparatus of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 1a 1st edge | side 1b 2nd edge | side 1c 3rd edge | side 1d 4th edge | side 2 Protective film 3 Waterproof sheet 11 Transparent conductive layer 12 Photoelectric conversion layer 13 Back surface electrode layer 14 Peripheral area | region 15, 15a, 15b X direction insulation groove 17, 18, 19 Groove 6 Power generation cell 6a, 6b End power generation cell 7 Single cell 10 Solar cell module 31, 32, 33 Water 40 Solar cell module evaluation device 41 AC characteristic measuring instrument 42 Information processing device 51 Capacitance calculation unit 52 Life Evaluation unit 53 Storage unit 101 Substrate 101a Interface 102 Protective film 103 Waterproof sheet 104 Metal frame 105 Water 106 Power generation cell 107 Water 108 Inverter 109a, 109b, 109d Cable 109c Between ground (ground)
110 Solar cell module 114 Surrounding area 115 Power source 116 Ammeter 117 Reference electrode

Claims (18)

(A) measuring a first capacitance between a first position and a second position of the solar cell module;
(B) exposing the solar cell module to a high humidity environment;
(C) measuring a second capacitance between the first position and the second position of the solar cell module after exposure to the high humidity environment;
(D) comprising the step of evaluating the flooded state of the solar cell module based on the first capacitance and the second capacitance,
The solar cell module is
A substrate,
A power generation cell provided apart from the first side of the substrate and including a transparent conductive layer, a photoelectric conversion layer, and a back electrode layer in this order on the substrate;
A protective layer covering the substrate and the power generation cell;
The second position is a position on the protective layer in the vicinity of the first side,
The method for evaluating a solar cell module, wherein the first position is a position on the substrate opposite to the power generation cell and a first distance from the first end portion on the first side of the power generation cell. In the evaluation method of the solar cell module according to claim 1,
The solar cell module is
Further comprising an end power generation cell separated from the power generation cell by a groove between the first side and the power generation cell,
The step (a) includes:
(A1) comprising the steps of attaching a first electrode to the first position and a second electrode to the second position,
The step (d) includes:
(D1) Based on the first capacitance and the second capacitance, a third capacitance between the second end portion on the power generation cell side and the first end portion of the end power generation cell. A step of estimating the capacity;
(D2) comprising, based on the third capacitance, evaluating a flooded state between the substrate and the protective layer between the second end and the first end,
The first capacitance and the second capacitance are capacitances between the first electrode and the second electrode,
The first distance is set to a size such that the capacitance between the transparent conductive layer and the first electrode of the power generation cell can be ignored when measuring the first capacitance and the second capacitance. And
The width of the first electrode in the first direction is a static width between the transparent conductive layer of the end power generation cell and the first electrode when measuring the first capacitance and the second capacitance. A method for evaluating a solar cell module that is set to a size that can ignore the electric capacity. In the evaluation method of the solar cell module according to claim 2,
The first distance is not less than 1000 times the first width in the first direction as between the power generation cell and the end power generation cell,
The method for evaluating a solar cell module, wherein a width of the first electrode in the first direction is 1000 times or more of the first width. In the evaluation method of the solar cell module according to claim 1,
The step (a) includes:
(A1) comprising the steps of attaching a first electrode to the first position and a second electrode to the second position,
The step (d) includes:
(D1) estimating a third capacitance between the first side and the first end based on the first capacitance and the second capacitance;
(D2) comprising, based on the third capacitance, evaluating a flooded state between the substrate and the protective layer between the first side and the first end,
The first capacitance and the second capacitance are capacitances between the first electrode and the second electrode,
The first distance is set to a size such that the capacitance between the transparent conductive layer and the first electrode of the power generation cell can be ignored when measuring the first capacitance and the second capacitance. And
The width of the first electrode in the first direction is large enough to ignore the capacitance between the first electrode and the second electrode when measuring the first capacitance and the second capacitance. The evaluation method of the solar cell module set to SA. In the evaluation method of the solar cell module according to claim 4,
The first distance is not less than 1000 times the second width in the first direction as between the second electrode and the power generation cell.
The method for evaluating a solar cell module, wherein a width of the first electrode in the first direction is 1000 times or more of the second width. In the evaluation method of the solar cell module according to any one of claims 2 to 5,
The step (d2) includes
(D21) A solar cell module including a step of estimating a water immersion amount of the solar cell module with reference to a water immersion amount table indicating a relationship between the capacitance and the water immersion amount based on the third capacitance. Evaluation method. In the evaluation method of the solar cell module according to any one of claims 2 to 6,
The step (d) includes:
(D3) The solar cell module evaluation method further comprising the step of estimating the lifetime of the solar cell module based on the flooded state. In the evaluation method of the solar cell module according to claim 7,
The step (d3) includes
(D31) A step of estimating the lifetime of the solar cell module with reference to a lifetime table showing a relationship between the capacitance, the high humidity environment and the lifetime based on the third capacitance and the high humidity environment. Evaluation method for solar cell module including In the evaluation method of the solar cell module according to any one of claims 1 to 8,
The step (b)
(B1) A solar cell module evaluation method comprising a step of placing the solar cell module in an environment change cycle including the high humidity environment. In the evaluation method of the solar cell module according to any one of claims 1 to 9,
The high-humidity environment is a solar cell module evaluation method including any one of water or a chemical substance having a predetermined temperature and a high-temperature and high-humidity chamber having a predetermined temperature and humidity. A measuring instrument comprising a first terminal and a second terminal, and measuring a capacitance between a first electrode connected to the first terminal and a second electrode connected to the second terminal;
An information processing device for obtaining an output from the measuring instrument,
The first electrode and the second electrode are respectively brought into contact with the first position and the second position of the solar cell module to be evaluated,
The measuring instrument is
Measuring a first capacitance between the first position and the second position;
After placing the solar cell module in a high humidity environment, measure a second capacitance between the first position and the second position,
The information processing apparatus includes:
Based on the first capacitance and the second capacitance, evaluate the flooded state of the solar cell module,
The solar cell module is
A substrate,
A power generation cell provided apart from the first side of the substrate and including a transparent conductive layer, a photoelectric conversion layer, and a back electrode layer in this order on the substrate;
A protective layer covering the substrate and the power generation cell;
The second position is a position on the protective layer in the vicinity of the first side,
The evaluation apparatus for a solar cell module, wherein the first position is on the substrate opposite to the power generation cell and is a position separated from the first end portion on the first side of the power generation cell by a first distance. In the evaluation apparatus of the solar cell module according to claim 11 ,
Before SL solar cell module, between the first side and the power generation cell, further comprising an end portion power generation cells separated from the power generation cell by a groove,
The information processing apparatus includes:
Based on the first capacitance and the second capacitance, the third capacitance between the second end on the power generation cell side and the first end in the end power generation cell is estimated. A capacitance calculating unit; a storage unit for storing the third capacitance;
An evaluation unit that evaluates a flooded state between the substrate and the protective layer between the second end and the first end based on a third capacitance;
The first capacitance and the second capacitance are capacitances between the first electrode and the second electrode,
The first distance is set to a size such that the capacitance between the transparent conductive layer and the first electrode of the power generation cell can be ignored when measuring the first capacitance and the second capacitance. And
The width of the first electrode in the first direction is a static width between the transparent conductive layer of the end power generation cell and the first electrode when measuring the first capacitance and the second capacitance. Evaluation device for solar cell module set to a size that can ignore the electric capacity. In the solar cell module evaluation apparatus according to claim 12,
The first distance is not less than 1000 times the first width in the first direction as between the power generation cell and the end power generation cell,
The evaluation apparatus for a solar cell module, wherein a width of the first electrode in the first direction is 1000 times or more of the first width. In the evaluation apparatus of the solar cell module according to claim 11,
A capacitance calculating unit that estimates a third capacitance between the first side and the first end based on the first capacitance and the second capacitance;
A storage unit for storing the third capacitance;
An evaluation unit that evaluates a flooded state between the substrate and the protective layer between the first side and the first end based on the third capacitance;
The first capacitance and the second capacitance are capacitances between the first electrode and the second electrode,
The first distance is set to a size such that the capacitance between the transparent conductive layer and the first electrode of the power generation cell can be ignored when measuring the first capacitance and the second capacitance. And
The width of the first electrode in the first direction is large enough to ignore the capacitance between the first electrode and the second electrode when measuring the first capacitance and the second capacitance. An evaluation device for a solar cell module set to the size. In the evaluation apparatus of the solar cell module according to claim 14,
The first distance is not less than 1000 times the second width in the first direction as between the second electrode and the power generation cell.
The evaluation apparatus for a solar cell module, wherein a width of the first electrode in the first direction is 1000 times or more of the second width. The solar cell module evaluation apparatus according to any one of claims 12 to 15, wherein the storage unit stores an inundation amount table indicating a relationship between an electrostatic capacity and an inundation amount of water,
The evaluation unit is a solar cell module evaluation apparatus that estimates the amount of water immersion of the solar cell module with reference to the water immersion amount table based on the third capacitance.   17. The solar cell module evaluation apparatus according to claim 12, wherein the evaluation unit further estimates a lifetime of the solar cell module based on the flooded state. . In the solar cell module evaluation apparatus according to claim 17,
The storage unit stores a life table indicating a relationship between capacitance, high humidity environment, and life,
The evaluation unit is a solar cell module evaluation apparatus that estimates the lifetime of the solar cell module with reference to the lifetime table based on the third capacitance and the high humidity environment.

Images