JP5657922B2 - Package of light quantity reference cell and light quantity measuring apparatus using the same - Google Patents

Description

  The present invention relates to a protection device for protecting a reference cell used for calibrating the irradiance of a light source system for measuring photoelectric conversion characteristics of a solar cell from the deterioration, and a reference cell device equipped with the protection device. And the light source system using the reference cell device.

  In recent years, while solar power generation has been widely taken up, new solar cells having various power generation characteristics such as multi-junction solar cells are being developed. On the other hand, there are few crystal silicon-based evaluation technologies that have already been developed that can be applied to new models as they are in order to correctly measure the performance of these solar cells.

  This is because the above-described new solar cell has a spectral sensitivity characteristic inherent to the material and structure, and its photoelectric conversion characteristics greatly depend on the spectral irradiance of the irradiation light for performance evaluation. In addition, the output characteristics of solar cells vary greatly depending on the climate, such as the amount of solar radiation, temperature, and wind conditions at the installation location. Therefore, in general, solar cell performance measurement is performed indoors using a light source system (solar simulator) having a spectral irradiance distribution approximated to reference sunlight under internationally agreed standard test conditions. There are many cases.

  In the measurement using this solar simulator, it is necessary to match the spectral irradiance distribution of the solar simulator with the spectral irradiance distribution of the reference sunlight in order to obtain an accurate measurement result. However, since there is actually a difference between the two, errors caused by spectrum mismatch are systematically included in the evaluation results unless some correction is performed.

  FIG. 19 shows an example of the difference in spectral irradiance between a solar simulator that uses a xenon lamp as a light source and improved in approximation by an optical filter or the like, and reference sunlight. This is the spectral irradiance of a solar simulator light source. It is understood that the spectral irradiance of the solar simulator light source relatively matches the spectrum of the reference sunlight on the short wavelength side, but the error increases on the long wavelength side.

  In order to reduce such errors in spectral irradiance, the degree of approximation of the solar simulator light source itself with respect to the reference sunlight may be further improved. There is. For this reason, the reference cell method of setting the irradiance of the solar simulator to be equivalent to the standard test conditions has been introduced and is widely used worldwide.

  In this reference cell method, a reference cell having the same relative spectral sensitivity characteristic as that of the solar cell to be evaluated, specifically, a product partly cut out as a sample and sealed in a predetermined package is prepared. Thereafter, the light quantity of the solar simulator is adjusted using this reference cell.

  Here, the solar cell has a stable characteristic such as a silicon crystal system using single crystal silicon, and a stable characteristic such as a thin film silicon in which amorphous silicon or microcrystalline silicon is formed on a transparent substrate. It is roughly divided into solar cells that are not. FIG. 20 shows spectral sensitivity characteristics of the silicon crystal solar cell.

  On the other hand, FIG. 21 shows the spectral sensitivity characteristics of the thin film silicon solar cell. As shown in this figure, a solar cell using thin film silicon has sensitivity only in a relatively narrow wavelength band. For this reason, in order to increase the conversion efficiency, a relatively high sensitivity cell is formed on the surface side on the short wavelength side indicated by the solid line, and a relatively high sensitivity cell is formed on the bottom side on the long wavelength side indicated by the broken line, The multi-junction solar cell obtained by joining them is manufactured.

  As shown in FIG. 20, the silicon crystal solar cell has spectral sensitivity in a wide wavelength range. On the other hand, as shown in FIG. 21, the multi-junction thin-film silicon solar cell has a narrow wavelength range with spectral sensitivity, and also has sensitivity at wavelengths where the spectral irradiances of the reference sunlight and solar simulator are greatly different. Therefore, from FIG. 19 described above, a solar simulator having a higher degree of coincidence of spectral irradiance is required for measurement of such a multi-junction thin-film silicon solar cell.

  By the way, since the characteristics of the silicon crystal solar cell are stable, a stable reference cell can be easily obtained. On the other hand, in the case of a thin-film silicon-based solar cell, a stable state cannot be maintained for a long time due to changes in physical properties such as light degradation and heat recovery. For this reason, the reference cell made of a thin-film silicon solar cell lacks the stability of the calibration value and is very difficult to reproduce the light amount adjustment result of the solar simulator.

  Conventionally, the following two types of pseudo cells have been proposed as the above-described thin-film silicon-based reference cells. First, in Patent Document 1, a pseudo cell in which the film thickness of the amorphous silicon layer is changed is selected in order to match the relative spectral sensitivity characteristic of the target pseudo cell with that of the solar cell to be measured. However, this method has a problem that since the amorphous silicon layer itself is physically unstable, a stable pseudo cell sufficient for calibration as a reference cannot be obtained.

  Similarly, in Patent Document 2, an example of a pseudo cell using a colored glass filter is described in paragraph 0144. However, as shown in FIGS. There is a problem that the characteristics of this change. 22 (a) and 23 (a) are graphs showing changes in light receiving sensitivity after 100 hours and 200 hours after irradiation of pseudocells with light of 1 sun intensity from a solar simulator. is there. The change in the light receiving sensitivity is obtained by subtracting the transmittance after transmission from the transmittance before irradiation. FIG. 22A and FIG. 23A show an example of the multi-junction thin film silicon solar cell, and FIG. 22 shows a relatively sensitive cell on the short wavelength side ( FIG. 23A shows a cell on the bottom side (bottom cell) having relatively high sensitivity on the long wavelength side.

  From FIG. 22A, in the top cell, for example, at 400 nm, after 100 hours, the light receiving sensitivity is reduced by 0.7%. On the other hand, from FIG. 23A, in the bottom cell, for example, at 600 nm, after 100 hours, the light receiving sensitivity is reduced by 0.1%. The spectral sensitivity characteristics of these top cell and bottom cell are shown in FIG. 22 (b) and FIG. 23 (b), respectively.

  In JIS C8941, in order to overcome the instability of the pseudo cell as described above, the light quantity of the solar simulator is adjusted using a pseudo cell in which an optical filter is pasted on a stable silicon crystal cell. I admit.

JP 2006-147755 A JP 2004-273870 A

When a pseudo cell as described above is created using an absorption type optical filter, it is necessary to first select a filter so as to meet a predetermined spectral sensitivity characteristic and to reduce light amount attenuation. However, the irradiance of the solar simulator is very large, as high as 100 mW / cm ² .

  Therefore, in the selection of the filter, if the priority is given to a filter with less solarization (a phenomenon in which spectral transmittance is deteriorated by exposure to ultraviolet radiation), the selection technique is narrowed, and the most important spectral sensitivity characteristic and light quantity are sacrificed. There is a problem that the expected pseudo cell cannot be obtained.

  An object of the present invention is to provide a solar cell measurement reference cell protection device capable of stabilizing the spectral sensitivity characteristics of a solar cell measurement reference cell, and a reference cell device and a light source system using the same.

The light quantity measurement reference cell package of the present invention has a reference cell storage portion for storing a reference cell used for calibrating the irradiance of a light source for measuring the photoelectric conversion characteristics of the solar battery. a package for a reference cell protection from ultraviolet radiation exposure was, as is irradiated onto the entrance of the housing criteria cell to the reference cell storage unit, apertures entering the measured light from the light source When, characterized in that it comprises a dimming element to cut the incidence of ultraviolet radiation from the previous SL apertures, a protection device having a drive unit for openably move reducer light member at the incident Prompt, the .

Therefore, even if the reference cell is a pseudo cell in which an optical filter is pasted on a stable silicon crystal cell, the unnecessary ultraviolet radiation exposure period is eliminated and the effect of solarization is minimized. The spectral sensitivity characteristics of the pseudo cell can be stabilized over a long period of time.
In addition, the protection device is mounted on the entrance of the reference (pseudo) cell and accommodated in the same package.
Therefore, it is possible to realize a reference cell device that can stably maintain the spectral transmission characteristics of the optical filter of the reference (pseudo) cell. In addition, the reference cell device is not limited to the solar simulator, and can recognize changes in the spectral distribution of the radiated light of any light source system that requires constant spectral radiation characteristics.

In the package of the light quantity measuring reference cell according to the present invention, the dimming member is a light blocking member that blocks light in the entire wavelength region of the light to be measured.

  According to the above configuration, a light shielding member such as a shutter is provided as the light reducing member, and the light shielding member is opened only when adjusting the light amount of the solar simulator, and the others are closed to cover the reference (pseudo) cell. Deterioration of the (pseudo) cell can be prevented.

Furthermore, in the package of the light quantity measuring reference cell of the present invention, the dimming member is a filter that cuts off the incidence of the ultraviolet radiation.

  According to said structure, the ultraviolet radiation cut filter which cuts the ultraviolet radiation of a wavelength range of about 400 nm or less as a said light reduction member is provided, and the calibration (light quantity adjustment) of the ultraviolet radiation cut filter is a reference (pseudo) The reference (pseudo) other than the ultraviolet radiation is used except when it is used, while the reference (pseudo) cell is covered with the reference (pseudo) cell to prevent deterioration (solarization) of the reference (pseudo) cell. Temporal fluctuations in the amount of light from the light source can be monitored with irradiation light that is less likely to degrade the cell.

Furthermore, the light quantity measuring device of the present invention includes a reference cell mounted in the light quantity measurement reference cell package, and is adjacent to the reference cell and more resistant to ultraviolet light than the reference cell. And a monitor cell having a low accuracy is provided, and the dimming member is reciprocated between the reference cell and the monitor cell by the driving unit.

  According to said structure, it is implement | achieved by the silicon sensor etc. without a filter adjacent to the said reference cell, and the ultraviolet radiation tolerance is higher than the said reference cell, and it is inferior to the said to-be-measured light ( A monitor cell (with a difference in spectral sensitivity) is provided, and the dimming member is reciprocated between the reference cell and the monitor cell by the drive unit.

  Thereby, calibration (light quantity adjustment) of the light source can be performed with high accuracy using the reference (pseudo) cell. Further, during the measurement of the solar battery, it is possible to monitor the temporal variation of the light amount of the solar simulator using the monitor cell. In addition, since the dimming member is retracted to the space on the monitor cell provided adjacent to the reference (pseudo) cell when unnecessary, the reference cell device can be realized in a compact manner.

In the light quantity measuring device of the present invention, at least one of the positive and negative output ends of the reference cell and the monitor cell is alternatively connected to a common output terminal in conjunction with the reciprocating motion of the light reducing member by the driving unit. It further comprises a switch to be connected.

  According to the above configuration, even if the protection device and the monitor cell are housed in the same package in the reference (pseudo) cell, the number of terminals drawn from the package can be reduced.

  The solar cell measurement reference cell protection device of the present invention and the reference cell device and light source system using the same are used for calibrating (light quantity adjustment) a light source for measuring the photoelectric conversion characteristics of the solar cell as described above. In protecting the reference cell from being deteriorated mainly by the incidence of the ultraviolet light, the reference cell is covered with a dimming member that cuts at least the ultraviolet radiation for an unnecessary time.

  Therefore, when measuring a solar cell of a multi-junction type other than a silicon crystal system as the solar cell, even if the reference cell is a pseudo cell in which an optical filter is pasted on a stable silicon crystal cell, The unnecessary radiation of ultraviolet radiation can be eliminated, the influence of solarization can be minimized, and the spectral sensitivity characteristics of the pseudo cell can be stabilized over a long period of time.

It is a block diagram of the solar simulator system which is a light source system concerning a 1st embodiment of the present invention. It is a figure for demonstrating an example of the reference | standard cell apparatus in the solar simulator system shown in FIG. It is a figure which shows the internal structure of the reference | standard cell apparatus shown in FIG. It is a figure for demonstrating the other example of the reference | standard cell apparatus in the solar simulator system shown in FIG. It is a figure which shows the internal structure of the reference | standard cell apparatus shown in FIG. It is a flowchart for demonstrating the measurement control operation | movement by the measurement control part using the reference | standard cell apparatus shown in FIG. 2 and FIG. It is a flowchart for demonstrating the conventional measurement operation | movement. It is a block diagram of the solar simulator system which concerns on the 2nd Embodiment of this invention. It is a figure for demonstrating an example of the switching circuit of the said reference cell and a monitor cell. It is a flowchart for demonstrating the measurement control operation | movement by the measurement control part of the solar simulator shown in FIG. It is a block diagram of the solar simulator system which concerns on the 3rd Embodiment of this invention. It is a graph which shows the passage characteristic of an ultraviolet radiation cut filter. It is a graph which shows the spectral sensitivity characteristic at the time of interposing the said ultraviolet radiation cut filter in the spectral sensitivity characteristic of the bottom cell in a multijunction type solar cell. It is a graph which shows the spectral sensitivity characteristic at the time of further interposing the said ultraviolet radiation cut filter in the spectral sensitivity characteristic of the top cell in a multijunction type solar cell. It is a flowchart for demonstrating the measurement control operation | movement by the measurement control part of the solar simulator shown in FIG. It is a figure for demonstrating the protection apparatus and reference | standard cell apparatus which concern on the 4th Embodiment of this invention. It is a front view of an example of the shutter used for the protection apparatus shown in FIG. It is a rear view of the shutter. It is a graph which shows the difference of spectral irradiance distribution with reference | standard sunlight and a solar simulator. It is a graph which shows the spectral sensitivity characteristic of the solar cell using a single crystal silicon. It is a graph which shows the spectral sensitivity characteristic of the solar cell using thin film silicon. It is a graph for demonstrating the mode of solarization of the top cell of the multijunction type solar cell using the said thin film silicon. It is a graph for demonstrating the mode of solarization of the bottom cell of the multijunction type solar cell using the said thin film silicon.

(Embodiment 1)
FIG. 1 is a block diagram of a solar simulator system that is a light source system according to a first embodiment of the present invention. This solar simulator system includes a solar simulator 1 and a reference cell device 2 for calibration. The solar simulator 1 measures the photoelectric conversion characteristics of a solar cell, and a light source 11 for irradiating a measured solar cell and a reference cell device 2 (not shown) with illumination light adjusted to a predetermined light amount, and the light source 11 The measurement control unit 12 controls the measurement operation such as the amount of light. Further, as will be described later, the light quantity adjustment (calibration) of the light source 11 of the own device is performed using the reference cell device 2 for each measurement of the characteristics of the solar cell to be measured for a predetermined time (predetermined quantity).

  It should be noted that the reference cell device 2 is configured to include a protection device 4 for protecting the reference cell 3. The reference cell 3 is used when the solar cell to be measured is a multi-junction type solar cell other than the silicon crystal type, and is used on the sensor 31 composed of a stable silicon crystal type cell. The pseudo cell is formed by pasting the optical filter 32. The optical filter 32 is used to match the spectral sensitivity characteristic of the sensor 31 with the spectral sensitivity characteristic of the solar cell to be measured with high accuracy. Both output terminals of the sensor 31 are connected to the measurement control unit 12.

  On the other hand, the protection device 4 covers the light shielding member 41 such as a shutter and the incident light entrance of the light to be measured in the reference cell 3 with the light shielding member 41 when measuring the photoelectric conversion characteristics of the solar cell. When the simulator 1 is calibrated, the simulator 1 includes an opening / closing mechanism 42 that is a drive unit for retracting the light shielding member 41.

  When the solar simulator 1 is calibrated, the temperature of the sensor 31 needs to be kept constant (25 ° C.). For this reason, the temperature sensor 51 and the cooling mechanism 52 are provided in close contact with the sensor 31. A configured cooling device 5 is provided.

  FIG. 2 is a diagram for explaining a reference cell device 2 a which is an example of the reference cell device 2. The reference cell device 2 a is configured by integrally sealing a protective device 4 in the housing 25 with the reference cell 3. The protective device 4 is disposed on the reference cell 3, and an opening 43 communicating with the measurement light incident port in the reference cell 3 is opened and closed by a pair of shutters 411 and 412 which are the light shielding members 41. 2 (b) is switched between the open state of the opening 43 and the closed state shown in FIG. 2 (a). 2 (a) and 2 (b) are front views of the reference cell device 2a, and FIG. 2 (c) is a side view.

  3A and 3B are diagrams showing the internal structure of the reference cell device 2a. FIG. 3A is a front view and FIG. 3B is a side view. The pair of shutters 411 and 412 is made of a rigid metal plate or the like, and moves in the direction away from and close to each other to open and close the opening 43, respectively. The opening / closing mechanism is such that brackets 4111 and 4121 provided at one end of the shutters 411 and 412 on the side orthogonal to the approaching / separating direction can slide on the guide shafts 4112 and 4122, respectively. The screws 4115 and 4125 fixed to the output shafts of the motors 4114 and 4124 are screwed into the brackets 4113 and 4123 provided at the other end, and the shutter 411 is rotated by the rotation of the motors 4114 and 4124. , 412 are displaced toward and away from each other.

  Lead wires 4116 and 4126 from the motors 4114 and 4124 are connected to the external connection terminal 44 and connected to the measurement control unit 12 of the solar simulator 1 via a cable (not shown). The lead wires 4116 and 4126 from the motors 4114 and 4124 may be connected to each other in parallel and integrally controlled by the measurement control unit 12, or may be individually routed and controlled. In addition, a control circuit for the motors 4114 and 4124 is provided in the protection device 4a. The control circuit receives an open / close signal from the measurement control unit 12 via the external connection terminal 44, and responds to the open / close signal. The motors 4114 and 4124 may be controlled. In that case, a limit switch or an overcurrent protection circuit may be provided to perform opening / closing operations of the shutters 411 and 412 and detection of an abnormality.

  FIG. 4 is a diagram for explaining a reference cell device 2b which is another example of the reference cell device 2. In FIG. Similarly to the above-described reference cell device 2a, the protection device 4b is used by covering the reference cell 3, and the reference cell device 2b has an opening 43 that communicates with an incident port of light to be measured in the reference cell 3. By being opened and closed by a pair of shutters 413 and 414 which are members 41, the open state of the opening 43 shown in FIG. 4B and the closed state shown in FIG. 4A are switched. 4 (a) and 4 (b) are front views of the reference cell device 2b, and FIG. 4 (c) is a side view.

  FIG. 5 is a diagram showing the internal structure of the reference cell device 2b, and FIGS. 5 (a) and 5 (b) are front views corresponding to FIGS. 4 (a) and 4 (b), respectively. The pair of shutters 413 and 414 is made of a rigid metal plate or the like, and moves in a direction away from and close to each other to open and close the opening 43, respectively. Therefore, first, these shutters 413 and 414 can be moved toward and away from each other by a guide (not shown). A winding spring 415 is suspended between both ends of the shutters 413 and 414 on the side orthogonal to the approaching / separating direction.

  The winding spring 415 is formed by extending both ends of the winding portion 415a as two arm portions 415b and 415c from the winding portion 415a, and exerts an elastic force in a direction in which the arm portions 415b and 415 are closed to each other. A pin 416 is fitted into the winding portion 415 a, and the pin 416 is prevented from coming off in a guide groove 262 extending substantially parallel to the facing surface of the shutters 413 and 414 on the upper surface plate 261 of the housing 26. And is slidable.

  Therefore, in a normal state, the elastic force of the winding spring 415 causes the shutters 413 and 414 to move toward each other, that is, in a closing direction, and the pin 416 slides in the guide groove 262. It is located in the vicinity of the end 262a on the side far from the opening 43, and is in the state shown in FIG. 4 (a) and FIG. 5 (a).

On the other hand, when the user displaces the pair of pins 416 so as to be close to each other against the elastic force of the winding spring 415, the two arms 415b and 415c of the winding spring 415 are disposed. Are separated from each other, so that the shutters 413 and 414 are also separated from each other, and the state shown in FIGS. 4B and 5B is obtained. In this state, the user holds the shutters 413 and 414 in an open state by locking the pin 416 to a locking portion provided at the end portion 262b on the side close to the opening 43 of the guide groove 262. Can do.

  When the user removes the pin 416 from the engaging portion, the pin 416 is moved to the end portion 262a far from the opening 43 of the guide groove 262 by the elastic force of the winding spring 415, and the shutters 413 and 414 are moved. It can be closed and the state shown in FIG. 4 (a) and FIG. 5 (a) is obtained.

  Therefore, the reference cell device 2a shown in FIGS. 2 and 3 is controlled by the measurement control unit 12 on the solar simulator 1 side to automatically open and close the shutters 411 and 412, whereas the reference cell device 2a shown in FIGS. The cell device 2b opens and closes the shutters 413 and 414 by a user's manual operation.

  FIG. 6 is a flowchart for explaining the measurement control operation by the measurement control unit 12 using the reference cell device 2a shown in FIG. 2 and FIG. When the solar simulator 1 is turned on in step S1, the measurement control unit 12 opens the shutters 411 and 412 in step S2, monitors the output of the sensor 31 in step S3, waits until it is stabilized, Move on to S4.

  In step S4, the measurement control unit 12 determines whether or not the output of the sensor 31 matches the reference value (short-circuit current Isc) previously assigned to the sensor 31, and if not, step S5 Then, the light quantity of the light source 11 is adjusted (calibrated), and the process returns to the step S4. Thus, the adjustment (calibration) is performed until the light quantity of the light source 11 becomes constant. After the adjustment, the measurement control unit 12 closes the shutters 411 and 412 in step S6, and measures the power generation amount of the solar cell to be measured in step S7.

  In step S <b> 8, the measurer determines whether there are any solar cells to be measured, and ends the process when all the solar cells have been measured. On the other hand, when the solar cell to be measured is left in step S8, the measurement control unit 12 elapses a predetermined time or more after adjusting the light amount of the photogen 11 in step S9. If it has elapsed, the process returns to step S2 to adjust the amount of light using the reference cell device 2a. If not, the process returns to step S7 to continue the measurement. To do.

  On the other hand, FIG. 7 shows, for reference, a measurement operation in a conventional solar simulator in which the protection device 4a is not provided, that is, only the reference cell 3 is used. The same process is shown with the same step number. Therefore, compared with FIG. 6, the opening / closing of the shutters 411 and 412 in steps S2 and S6 and the periodic light amount adjustment (calibration) timing determination in step S9 are not performed. 6 and FIG. 7, the shaded step is a period in which the reference cell 3 is exposed to the irradiation light from the solar simulator 1, although in FIG. 7 it is exposed throughout the entire measurement period. On the other hand, in FIG. 6, exposure is performed only during the light amount adjustment (calibration) period, and deterioration of the optical filter 32 of the reference cell 3 can be suppressed.

  In the above-described example, the shutters 411 and 412 are automatically opened and closed using the protection device 4a. However, when the manual protection device 4ba is used, instead of the opening and closing operations in steps S2 and S6, What is necessary is just to alert | report that a user should open and close.

  As described above, in the present embodiment, the protection device 4a, 4b is covered in the reference cell 3 used to calibrate the solar simulator 1 for measuring the photoelectric conversion characteristics of the solar cell, and the protection device The light shielding member 41 (shutters 411, 412; 4a, 4b) is covered with respect to the light entrance of the light to be measured in the reference cell 3 when measuring the photoelectric conversion characteristics of the solar cell and opened when the solar simulator 1 is calibrated. 413, 414) and an opening / closing mechanism 42 for driving it.

  Therefore, when measuring a solar cell other than a silicon crystal system, particularly a multi-junction type solar cell, the reference cell 3 has an optical filter 32 attached on a stable silicon crystal cell (sensor 31). Even in the case of a pseudo cell, exposure by irradiation light for an unnecessary period is eliminated (the effect of solarization of the optical filter 32 is minimized), and the spectral sensitivity characteristics of the pseudo cell (reference cell 3) are maintained over a long period of time. It can be stabilized.

  Further, by mounting the protection device 4 on the entrance of the reference (pseudo) cell 2 and storing them in the same package, the spectral transmission characteristics of the optical filter 32 of the reference (pseudo) cell 2 can be stabilized. The reference cell device 2 that can be maintained can be realized. In addition, the reference cell device 2 is not limited to the solar simulator 1, and can recognize changes in the spectral distribution of the radiated light of any light source system that requires a certain spectral radiation characteristic. You can also.

(Embodiment 2)
FIG. 8 is a block diagram of a solar simulator system according to the second embodiment of the present invention. This solar simulator system is similar to the solar simulator system shown in FIG. 1 described above, and corresponding portions are denoted by the same reference numerals, and description thereof is omitted. It should be noted that in this solar simulator system, the reference cell device 2 ′ is adjacent to the reference cell 3 and has higher ultraviolet radiation resistance than the reference cell 3 with respect to the light to be measured. The monitor cell 3 'is inferior to that (has a shift in spectral sensitivity), and the light shielding member 41 is reciprocated between the reference cell 3 and the monitor cell 3' by the opening / closing mechanism 42.

  Specifically, the monitor cell 3 'is realized by a stable silicon sensor 31' without an optical filter. The reference cell 3 is used for adjusting the light amount (short-circuit current Isc), that is, adjusting the absolute value as described above, whereas the monitor cell 3 'is used for checking the temporal variation of the light amount. Used. Therefore, the outputs from the two sensors 31, 31 'are input to the measurement control unit 12' of the solar simulator 1 '.

  When two cells 3 and 3 ′ are provided in one reference cell device 2 ′ in this way, at least one of the positive and negative output ends of the reference cell 3 and the monitor cell 3 ′ is connected to a light shielding member 41 by the opening / closing mechanism 42. The switch may be switched in conjunction with the reciprocating motion of the motor and alternatively connected to a common output terminal.

  FIG. 9 shows an example in which both positive and negative output terminals of the reference cell 3 and the monitor cell 3 'are switched by switches F1 and F2 and are selectively connected to positive and negative output terminals P1 and P2. With this configuration, even if the protective device 4 and the monitor cell 3 'are housed in the same package in the reference cell 3, the number of terminals drawn from the package can be reduced.

  FIG. 10 is a flowchart for explaining a measurement control operation by the measurement control unit 12 ′ of the solar simulator 1 ′. Similar to the processing of FIG. 6, corresponding steps are denoted by the same step numbers. First, in the solar simulator 1 ′, when the power of the solar simulator 1 is turned on in step S1, the measurement control unit 12 ′ drives the light shielding member 4 in step S2 ′ to move the monitor cell 3 ′ (sensor B) side. Open and close the reference cell 3 (sensor A) side. In step S11, the measurement control unit 12 'monitors the output of the sensor 31' (sensor B), waits until it stabilizes, and proceeds to step S12.

  In step S12, the measurement control unit 12 'drives the light shielding member 4, opens the reference cell 3 (sensor A) side, and closes the monitor cell 3' (sensor B) side. Subsequently, in step S3 ', the measurement control unit 12' monitors the output of the sensor 31 (sensor A), waits until it is stabilized, and proceeds to step S4 '. In step S4 ′, the measurement control unit 12 ′ determines whether or not the output of the sensor 31 (sensor A) matches the reference value (short-circuit current Isc) previously assigned to the sensor 31. If not, the light quantity of the light source 11 is adjusted (calibrated) in step S5, and the process returns to the step S4 ′. Thus, the adjustment (calibration) is performed until the light quantity of the light source 11 becomes constant.

  After the adjustment, the measurement control unit 12 'drives the light shielding member 4 in step S13, opens the monitor cell 3' (sensor B) side, and closes the reference cell 3 (sensor A) side. Thereby, the output of the monitor cell 3 ′ (sensor B) at the light amount adjusted in step S <b> 5 can be priced, and the measurement control unit 12 ′ stores the output as a value X in step S <b> 14.

  Thereafter, the measurement control unit 12 'checks the output of the monitor cell 3' (sensor B) in step S15 while measuring the power generation amount of the solar cell to be measured in step S7. As a result, when the value is within a predetermined range ± Y% from the value X, the measurement control unit 12 ′ performs the end determination of the step S8, and when the solar cell to be measured remains, the process proceeds to the step S7. Return to continue the measurement, and terminate the process if it is not left. On the other hand, when the output of the monitor cell 3 ′ (sensor B) exceeds the predetermined range ± Y% from the value X in step S15, the measurement control unit 12 ′ performs light amount adjustment using the reference cell 3 from step S12. Do.

  With this configuration, calibration (light quantity adjustment) can be performed with high accuracy using the reference (pseudo) cell 3, and other than that, temporal fluctuations in the light quantity of the solar simulator 1 ′ using the monitor cell 3 ′. That is, it is possible to monitor the deterioration of the light source 11 and automatically calibrate the light amount. Thereby, the reliability of the solar simulator 1 'can be ensured. In addition, since the light shielding member 4 is retracted in the space above the monitor cell 3 ′ adjacent to the reference (pseudo) cell 3 when not necessary, the reference cell device 2 ′ can be realized in a compact manner.

  On the other hand, in place of the monitor cell 3 ′, another reference cell having a configuration similar to that of the reference cell 3 is provided, the spectral sensitivity characteristics of the optical filter 32 between them are made different from each other, and they are alternately arranged. Alternatively, by simultaneously opening and closing the light shielding member 41 and performing light quantity measurement, it is possible to cope with changes in spectral irradiance distribution due to the aging of the light source 11 of the solar simulator 1 ′.

(Embodiment 3)
FIG. 11 is a block diagram of a solar simulator system according to the third embodiment of the present invention. This solar simulator system is similar to the solar simulator system shown in FIG. 1 described above, and corresponding portions are denoted by the same reference numerals, and description thereof is omitted. It should be noted that this solar simulator system uses an ultraviolet radiation cut filter 41 ″ instead of the light shielding member 41 in the protection device 4 ″ of the reference cell device 2 ″. As shown in FIG. 12, the ultraviolet radiation cut filter 41 ″ cuts light in a wavelength region of approximately 400 nm or less.

  Thereby, in the above-mentioned multi-junction solar cell, the spectral sensitivity characteristic of the bottom cell having relatively high sensitivity on the long wavelength side is indicated by the phantom line in FIG. 13 through the ultraviolet radiation cut filter 41 ″. However, the spectral sensitivity characteristic of the top cell having a relatively high sensitivity on the short wavelength side is almost the same as indicated by the solid line, whereas the spectral sensitivity characteristic of the top cell is shown in FIG. By interposing 41 ″, the characteristics are changed to those indicated by broken lines, and the components on the short wavelength side indicated by hatching are cut.

  However, much of the energy of the irradiation light of the solar simulator remains in the transmission region of the ultraviolet radiation cut filter 41 ″, and the monitor cell 3 ′ shown in FIG. 8 is measured by measuring the amount of light in this transmission region. The reference cell 3 can have this function. As a result, the package can be reduced in size, and the temporal variation of the light amount of the solar simulator 1 ″ can be monitored without increasing the number of terminals.

  Therefore, the measurement control operation by the measurement control unit 12 ″ of the solar simulator 1 ″ when using the reference cell device 2 ″ is as shown in FIG. In this operation, operations similar to those in FIG. 6 are denoted by the same step numbers. When the solar simulator 1 ″ is turned on in step S1, the measurement control unit 12 ″ inserts an ultraviolet radiation cut filter 41 ″ in step S21, and monitors the output of the sensor 31 in step S3 to stabilize the measurement. In step S22, the ultraviolet radiation cut filter 41 ″ is removed, and the process proceeds to step S4.

  In step S4, the measurement control unit 12 '' determines whether or not the output of the sensor 31 matches the reference value (short circuit current Isc) previously set for the sensor 31, and if not, In step S5, the light amount of the light source 11 is adjusted (calibrated), and the process returns to step S4. Thus, adjustment (calibration) is performed until the light amount of the light source 11 becomes constant.

  After the adjustment, the measurement control unit 12 ″ inserts the ultraviolet radiation cut filter 41 ″ in step S23, and stores the output of the sensor 31 in that state as the value X in step S14 ″. Thereafter, the measurement control unit 12 ″ checks the output of the sensor 31 in step S15 while measuring the power generation amount of the solar cell to be measured in step S7. As a result, when the value is within a predetermined range ± Y% from the value X, the measurement control unit 12 ′ performs the end determination of the step S8, and when the solar cell to be measured remains, the process proceeds to the step S7. Return to continue the measurement, and terminate the process if it is not left. On the other hand, when the output of the sensor 31 exceeds the predetermined range ± Y% from the value X in step S15, the measurement control unit 12 '' removes the ultraviolet radiation cut filter 41 '' in step S22, The light amount adjustment using the reference cell 3 from S4 is performed.

  In this way, the ultraviolet radiation cut filter 41 ″ is retracted from the reference cell 3 when the solar simulator 1 ″ is calibrated (light quantity adjustment), and the others are covered with the reference cell 3, thereby degrading the reference cell 3. (Effect of solarization) While avoiding calibration, the solar cell radiation other than the ultraviolet component, which is less likely to degrade the reference cell 3, is not affected by the radiation of the solar simulator, and the solar simulator 1 ″ changes with time. Can be monitored.

  The effect of the ultraviolet radiation cut filter 41 ″ is shown in FIGS. 22 (c) and 23 (c). As described above, these figures show how the sensitivity of the top cell and the bottom cell in the multi-junction solar cell using thin-film silicon decreases when the ultraviolet radiation cut filter 41 ″ is inserted. It is shown. In the top cell shown in FIG. 22 (c), the degree of decrease in light receiving sensitivity is small (suppressed by 0.2% after 100 hours at 400 nm), and in the bottom cell shown in FIG. It is understood that there is no.

(Embodiment 4)
FIG. 16 is a diagram for explaining a protection device 4 ′ ″ and a reference cell device 2 ′ ″ according to a fourth embodiment of the present invention. FIG. 16 (a) and FIG. It is those front views and side views. It should be noted that in the present embodiment, the reference cell device 2 ′ ″ only includes the above-described reference cell 3, and the protection device 4 ′ ″ is different from the reference cell device 2 ′ ″. And is mounted on the reference cell device 2 '''. Therefore, a protective device 4 ′ ″ for protecting the existing reference cell device 2 ′ ″ can be provided later.

  In the protection device 4 ′ ″, a shutter 49 having four blades 491 to 494 in each of the front curtain and the rear curtain is used as a light shielding member. 17 is a front view of the shutter 49, and FIG. 18 is a rear view. FIG. 17 shows a state where the shutter 49 is closed, and FIG. 18 shows a state where the shutter 49 is opened. When FIG. 17 shows a charged (before opening) state, the four blades 491 to 494 indicate the leading curtains 491f to 494f, and when not charging (after opening), the four blades 491 to 494f indicate the four sheets. The blades 491 to 494 indicate rear curtains 491r to 494r.

  The four blades 491f to 494f; 491r to 494r are supported by the links 495f and 495r so as to be movable in parallel on the base 496 so that the opening 497 facing the sensor 31 can be opened and closed. It has become. The blades 491f to 494f; 491r to 494r are charged by the charge unit in the control unit 498 which is an opening / closing mechanism, and the opening / closing is controlled by the release unit. Thus, the protection device 4 ′ ″ and the reference cell device 2 ′ ″ may be configured separately.

  In the above-described embodiment, the pseudo cell is used to adjust the light amounts of the solar simulators 1, 1 ′, 1 ″. However, the light source is not necessarily limited to the solar simulator, and various light sources are used. But you can. For example, by comparing the sensor output during actual sunlight illumination such as outdoors with the sensor output (= reference value) during reference sunlight illumination, the relative intensity of the actual sunlight relative to the reference sunlight is compared. Is possible.

1, 1 ′, 1 ″ Solar simulator 11 Light source 12, 12 ′, 12 ″ Measurement control unit 2; 2a, 2b; 2 ′; 2 ″; 2 ′ ″ Reference cell device 25, 26 Case 3 Reference Cell 3 'Monitor cell 31 Sensor 31' Silicon sensor 32 Optical filter 4; 4a, 4b; 4 "; 4 '" Protection device 41 Light blocking member 41 "Ultraviolet radiation cut filter 411, 412; 413, 414 Shutter 415 Winding spring 416 pin 42 opening / closing mechanism 43 opening 44 external connection terminal 49 shutter 491-494 blade 491f-494f front curtain 491r-494r rear curtain 495f, 495r link 497 opening 498 control unit 5 cooling device 51 temperature sensor 52 cooling mechanism F1, F2 switch P1 , P2 output terminal

Claims (5)

A reference cell storage unit for storing a reference cell used for calibrating the irradiance of a light source for measuring photoelectric conversion characteristics of a solar cell, and for protecting the stored reference cell from ultraviolet radiation exposure A package,
As is irradiated onto the entrance of the housing criteria cell to the reference cell storage unit, and an open port for incident light to be measured from the light source,
A dimming member to cut the incidence of ultraviolet radiation from the previous SL apertures, a protection device having a drive unit for openably move reducer light member at the incident Prompt,
A package of a reference cell for measuring the amount of light.   2. The light quantity measuring reference cell package according to claim 1, wherein the dimming member is a light blocking member that blocks light in the entire wavelength region of the light to be measured.   2. The light quantity measuring reference cell package according to claim 1, wherein the dimming member is a filter for cutting off the incidence of the ultraviolet radiation. A reference cell is mounted on the package of the reference cell for light quantity measurement according to any one of claims 1 to 3,
Adjacent to the reference cell, a monitor cell having higher ultraviolet radiation resistance than the reference cell and less accurate than the reference cell is provided, and the dimming member includes a reference cell and a monitor cell. The light quantity measuring device is reciprocated by the drive unit. A switch that selectively connects at least one of the positive and negative output ends of the reference cell and the monitor cell to a common output terminal in conjunction with the reciprocation of the light-reducing member by the drive unit; The light quantity measuring device according to claim 4.

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