JP4180295B2 - Granular solar cell performance measuring device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a granular solar cell performance measuring apparatus, and more particularly to a granular solar cell performance measuring apparatus that allows photoelectric conversion performance to be measured by making light incident on the granular solar cell from all directions.
[0002]
[Prior art]
Various solar cells have been put into practical use as solar cells that convert sunlight into electrical energy. A conventional general solar cell is a planar light receiving structure in which a p-type or n-type semiconductor layer is formed on the surface of a substrate, and a pn junction and an electrode are formed on the semiconductor layer, and light is received only from the main surface. And generate photovoltaic power. As the semiconductor, p-type or n-type single crystal silicon, polycrystalline silicon, amorphous silicon, or the like is employed. In the case of mass-produced solar cells that are put into practical use, the photoelectric conversion efficiency for converting incident light energy into electric energy is about 12 to 14%, and the photoelectric conversion efficiency is gradually improved by various improvements. is doing.
[0003]
It is very important and difficult to correctly evaluate the photoelectric conversion performance of a solar cell. Conventionally, when measuring the photoelectric conversion performance of a panel-shaped solar cell, the panel-shaped solar cell is accommodated in a solar simulator, and the solar cell is irradiated with pseudo-sunlight equivalent to sunlight from one side of the photovoltaic cell. And the VI characteristics of the solar cell are measured. This solar simulator has a metal casing, a xenon lamp, a condenser mirror, a cooling fan, a shutter, a spectrum correction filter, an indexer, an illuminance monitor, a beam splitter, a collimator lens, a plurality of other mirrors, a control unit, and the like. belongs to.
[0004]
On the other hand, as shown in WO98 / 15983, the inventor of the present application proposes a spherical solar cell (solar cell) or a cylindrical solar cell (solar cell) having a size of about 1 to 3 mm. A solar panel arranged in a matrix is under development. These solar cells are configured to receive light from almost the entire surface except for the part where the positive and negative electrodes are formed. In this solar panel under development, although solar light is received from the upper surface side, A reflection film that reflects light escaping downward to the solar cell is formed upward, and the solar cell receives light from almost the entire surface, and measures are taken to increase the light utilization rate using sunlight.
[0005]
[Problems to be solved by the invention]
In order to evaluate the photoelectric conversion performance of a granular (spherical or cylindrical) solar cell applied to the solar cell panel under development by the applicant of the present invention, the above-described existing solar simulator is used. Can only evaluate the power generation performance of simulated solar light incident from one side, and it does not take into account the characteristics peculiar to granular solar cells that light can be received from almost the entire surface. The electromotive force performance cannot be evaluated correctly.
An object of the present invention is to provide a granular solar cell performance measuring apparatus capable of measuring photoelectric conversion performance by causing a granular solar cell to receive pseudo sunlight from all directions.
[0006]
[Means for Solving the Problems]
The granular solar cell performance measuring apparatus according to claim 1 is an apparatus for measuring the photovoltaic power by irradiating light to the solar cell in order to measure the photoelectric conversion performance of the granular solar cell. An openable and closable main body case in which a measurement chamber is formed, a reflective coating formed on the inner surface of the measurement chamber, a xenon lamp disposed so that a light emitting portion faces the measurement chamber, and the xenon lamp electrically to a driving unit for driving, the solar cell holding means for holding so as to place the solar cell of the granular center of the measuring chamber, electrically connected to the solar cell of the particulate held in the solar cell holding means And a photovoltaic power measuring means for measuring the photovoltaic power.
[0007]
When measuring the photoelectric conversion performance of a granular solar cell, when the xenon lamp is electrically driven by the drive unit, the light emitted from the xenon lamp is reflected by the reflective film on the inner surface of the spherical measurement chamber inside the main body case. Thus, the light intensity is almost uniform over the entire area inside the measurement chamber. The xenon lamp is driven and controlled so that the light intensity is the same as that of natural sunlight (for example, 100 mW / cm ² ).
[0008]
The solar cell of particulate held in so that is disposed in the center of the measuring chamber by the solar cell retaining means a photovoltaic generated by receiving from all directions, electrically to the photovoltaic solar cell It is measured by the connected photovoltaic power measuring means. In this way, the solar cell can receive light from all directions to generate a photoelectromotive force, and the photoelectromotive force can be measured. In the same manner as the actual use mode of the granular solar cell, the granular solar cell It becomes possible to evaluate the photoelectric conversion performance.
[0009]
The granular solar cell performance measuring apparatus according to claim 2 is an apparatus for measuring the photovoltaic power by irradiating light to the solar cell in order to measure the photoelectric conversion performance of the granular solar cell. An openable / closable main body case in which a measurement chamber is formed, a reflective coating formed on the inner surface of the measurement chamber, a light guide path formed in communication with the measurement chamber in the main body case, and an exterior of the main body case A xenon lamp that supplies light to the measurement chamber via a light guide, a drive unit that electrically drives the xenon lamp, and a granular solar cell that is disposed in the center of the measurement chamber A solar cell holding means, and a photovoltaic power measuring means electrically connected to the granular solar cell held by the solar cell holding means and measuring the photovoltaic power.
[0010]
When the xenon lamp is caused to emit light by driving the xenon lamp by the drive unit, the light is introduced from the light guide into the measurement chamber, reflected by the reflective film on the inner surface of the measurement chamber, and almost uniform over the entire measurement chamber. It becomes various light intensity. That is, the invention of claim 1 differs from the invention of claim 1 only in the means for introducing light into the measurement chamber, and the other configurations are the same.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described.
As shown in FIG. 1, the granular solar cell performance measuring apparatus 1 includes a main body case 10, a spherical measurement chamber 2 formed in the main body case 10, a xenon lamp 4 and a spectral correction filter 4 a, and a measurement chamber 2. An illuminometer 5 for measuring illuminance, a cooling fan 6, a conductive pipe 7 and a conductive rod 8 for detecting photovoltaic power generated in the solar cell 3, a thermistor for measuring the temperature of the solar cell 3 incorporated in the conductive pipe 7, A measurement control device 17 and a drive unit 18 are included.
[0012]
The main body case 10 is made of an appropriate metal material (for example, aluminum or steel) and includes three blocks (a lower block 10a, an upper fixing block 10b, and an opening / closing block 10c). The upper fixing block 10b includes a plurality of lower fixing blocks 10a. The bolt 11 is fixed. The open / close block 10c is connected to the open / close block via the hinge portion 12 so as to be switched between a closed use position as shown in the figure and an open position where the measurement chamber 2 is opened as shown in the chain line. On an upper end surface of the upper fixed block 10b, a lock piece 13 capable of locking the open / close block 10c in a use position is provided so as to be rotatable around a vertical axis.
[0013]
Inside the main body case 10, there is formed a spherical measurement chamber 2 for accommodating the granular solar cell 3, for example, a measurement chamber 2 having a diameter of about 5 to 10 cm, and is formed on the inner surface of the measurement chamber 2. Is formed with a reflective film 2a made of an MgO thin film or a nickel plating film. The xenon lamp 4 is, for example, about 100 W, and is attached to the wall so that the light emitting portion faces the measurement chamber 2. The xenon lamp 4 is electrically connected to the drive unit 18 and is driven by the drive unit 18.
[0014]
A shielding plate 4 b that prevents light emitted from the xenon lamp 4 from directly entering the solar cell 3 is provided. The spectrum correction filter 4a is for removing a plurality of specific spectral components that are not present in sunlight from the emitted light of the xenon lamp 4 and converting them into pseudo sunlight, and covers the outside of the shielding plate 4b. It is formed in a partial spherical shape, and its lower end is fixed to the wall of the measurement chamber 2. The light emitted from the xenon lamp 4 is reflected by the shielding plate 4b toward the reflective coating 2a, reflected by the reflective coating 2a on the inner surface of the measurement chamber 2, and then passes through the filter 4a. As the light is emitted and repeatedly reflected by the reflective coating 2 a, the entire measurement chamber 2 is uniformly filled, enters the solar cell 3 from all directions, and part of the light enters the illuminometer 5.
[0015]
The illuminometer 5 is for measuring the illuminance (light intensity) in the measurement chamber 2, and is arranged not toward the solar cell 3 but in the direction near the solar cell 3 and attached to the wall surface of the measurement chamber 2. The illuminometer 5 is electrically connected to the measurement control device 17.
When a large number of solar cells 3 are continuously measured for a long time, a fan 6 is provided on the outer surface of the lower block 10 a of the main body case 10 to cool the main body case 10. An air passage 14 leading to the measurement chamber 2 and an exhaust passage 15 are formed in the main body case 10.
[0016]
The conductive pipe 7 is vertically disposed immediately below the center of the measurement chamber 2 and extends through the lower end wall portion of the main body case 10 to the vicinity of the center of the measurement chamber 2. The conductive pipe 7 is insulated from the main body case 10 and the reflective coating 2 a and is electrically connected to the measurement control device 17. A mounting portion 7a that is electrically connected to the positive electrode 3a (or the negative electrode) of the solar cell 3 is formed at the upper end of the conductive pipe 7, and three sharp portions are formed in the mounting portion 7a. The conductive pipe 7 is electrically connected to the measurement control device 17. Inside the mounting portion 7 a of the conductive pipe 7, a thermistor (not shown) for measuring the temperature of the solar cell 3 is provided, and this thermistor is also electrically connected to the measurement control device 17.
[0017]
The conductive rod 8 is arranged vertically right above the center of the measurement chamber 2 and extends through the upper end wall portion of the upper fixed block 10 b of the main body case 10 to the vicinity of the center of the measurement chamber 2. The upper portion of the conductive rod 8 protrudes to the outside of the main body case 10 by a predetermined length. The conductive rod 8 is electrically insulated from the main body case 10 and the reflective coating 2 a and is electrically connected to the measurement control device 17. A contact portion 8a that is electrically connected to the negative electrode 3b (or the positive electrode) of the solar cell 3 is formed at the lower end of the conductive rod 8, and three sharp portions are formed in the contact portion 8a.
[0018]
The conductive rod 8 is attached to the main body case 10 so as to be movable up and down and is urged downward by a tension spring 16. When the solar cell 3 is set in the measurement chamber 2, after the lock piece 13 is rotated to release the lock, the open / close block 10c is switched to the open position, the conductive rod 8 is lifted upward, and then the mounting portion 7a. When the solar cell 3 is set as shown in FIG. 1 between the contact portion 8a and the conductive rod 8 is moved downward by the biasing force of the tension spring 16, the contact portion 8a is brought into contact with the negative electrode 3b. The solar cell 3 is sandwiched between the mounting portion 7a and the contact portion 8a while being supported by the portion 7a. The solar cell 3 is held at the center of the measurement chamber 2 as shown in FIG. And the conductive rod 8 are electrically connected to the positive and negative electrodes 3 a and 3 b of the solar cell 3. The conductive pipe 7 and the conductive rod 8 correspond to the solar cell holding means.
[0019]
The measurement control device 17 includes a microcomputer, an input / output interface, a V-I detector that detects the voltage V and current I of the photovoltaic power generated by the solar cell 3, a fan drive circuit, and data to an external personal computer. For example, a data communication modem 17a. The microcomputer of the control device 17 includes a program for driving and controlling the xenon lamp 4, a program for measuring the illuminance in the measurement chamber 2 based on the detection signal of the illuminance meter 5, and the photovoltaic voltage V generated in the solar cell 3. Various control programs such as a program for detecting I and I, a program for measuring the temperature of the solar cell 3 from the detection signal of the thermistor, and a program for driving and controlling the fan 6 are stored in advance. The drive unit 18 drives the xenon lamp 4 under the control of the control device 17.
[0020]
Next, an example of the granular solar cell 3 will be described with reference to FIG.
This solar cell 3 includes a spherical crystal 3c having a diameter of about 1.5 mm made of, for example, a p-type silicon semiconductor, an n-type substantially spherical diffusion layer 3d formed by diffusing phosphorus or the like in the surface layer portion, and a spherical crystal. An approximately spherical pn junction 3e at the boundary between 3c and the diffusion layer 3d, an insulating coating 3f for surface protection and antireflection, a positive electrode 3a electrically connected to the spherical crystal 3c, and an n-type diffusion layer 3d And negative electrode 3b electrically connected to the. The positive electrode 3a and the negative electrode 3b are positioned substantially symmetrically with the center of the spherical crystal 3c interposed therebetween. When this solar cell 3 receives pseudo-sunlight, holes and electrons are photoexcited and separated by the pn junction 3e to generate photovoltaic power. In this solar cell 3, light can be received from almost all directions except for the portions where the positive and negative electrodes 3a and 3b are present.
[0021]
Next, the effect | action which measures the photoelectric conversion performance of the solar cell 3 with the granular solar cell performance measuring apparatus 1 demonstrated above is demonstrated.
First, after opening the opening / closing block 10c, the solar cell 3 is set in a sandwiched state between the placement portion 7a and the contact portion 8a, the positive electrode 3a is brought into contact with the placement portion 7a, and the negative electrode 3b. Is brought into contact with the contact portion 8a, the open / close block 10c is closed, and the lock piece 13 is switched to the lock position. Next, when a start switch provided in the control device 17 is operated, the measuring device 1 starts to operate, outputs a control signal from the control device 17 to the drive unit 18, and outputs a control signal from the drive unit 18 to the xenon lamp 4. The drive power is applied to cause the xenon lamp 4 to emit light, the control device 17 activates the fan 6 and the illuminometer 5 is activated.
[0022]
After the energization of the xenon lamp 4 has started, the operation of the xenon lamp 4 is stabilized and the measurement chamber 2 is filled with light. If the value does not reach the value (for example, 100 mW / cm ² ), the drive current output to the xenon lamp 4 is adjusted, and when the light intensity reaches a predetermined value, the control device 17 causes the photovoltaic device 3 to emit light. The power (voltage V and current I) is measured and the data is stored in memory. At the same time, the temperature of the solar cell 3 is detected from the detection signal of the thermistor, and the temperature data is also stored in the memory.
[0023]
The control device 17 is connected to a personal computer, and various data (at least illuminance data, voltage data, current data, temperature data) stored in the memory are transmitted and output to the personal computer. By repeating the above, it is possible to sequentially perform measurements on a large number of solar cells 3, measure the photovoltaic power of the solar cells 3, and accumulate the data.
[0024]
In this measurement apparatus 1, the spherical measurement chamber 2 is filled with pseudo-sunlight generated by the xenon lamp 4, is set to have the same light intensity as natural sunlight, and the solar cell 3 receives light from all directions, The photovoltaic power of the solar cell 3 can be measured. Therefore, it is possible to accurately measure the photovoltaic power of the solar cell 3 and accurately evaluate the photoelectric conversion performance of the solar cell. As can be seen from the above, this granular solar cell performance measuring device 1 is also used as an inspection device for inspecting the performance of granular solar cells.
[0025]
Next, an example in which the embodiment is partially changed will be described.
Since the granular solar cell performance measuring apparatus 1A shown in FIG. 3 has substantially the same structure as the measuring apparatus 1, only different structures will be described, and the same structure as the measuring apparatus 1 of the embodiment will be described. The same reference numerals are given and description thereof is omitted.
[0026]
As shown in FIG. 3, the xenon lamp 4 </ b> A is disposed outside the main body case 10. Below the shielding plate 4b, the lower block 10a of the main body case 10 is formed with a light guide path 19 formed of a tapered hole. A xenon lamp 4A similar to the above is disposed outside the light guide path 19, and the xenon lamp 4A. A partially spherical reflecting plate 4 c is provided for reflecting the light generated in step 1 toward the light guide path 19. The shielding plate 4b and the filter 4a are the same as described above.
[0027]
The light generated by the xenon lamp 4A is introduced from the light guide 19 into the measurement chamber 2, and after being redirected by the shielding plate 4b, passes through the filter 4a and is introduced to the outside of the filter 4a. Thus, since the xenon lamp 4A is installed outside the main body case 10, the heat load of the xenon lamp 4A is reduced, and maintenance and inspection of the xenon lamp 4A are simplified. In addition, the effect | action and effect which measure the photoelectric conversion performance of the spherical solar cell 3 are the same as the effect | action and effect of the said granular solar cell performance measuring apparatus 1. FIG.
[0028]
In the above embodiment, the spherical solar cell is described as an example of the granular solar cell. However, the granular solar cell is not limited to the spherical solar cell, and has a diameter of about 1 to 3 mm. There is also a case of a cylindrical granular solar cell having a length of about 1 to 3 mm. The granular solar cell performance measuring device of the present invention is not limited to the above-described embodiment, and can be implemented in various forms without departing from the gist of the present invention. Of course.
[0029]
【The invention's effect】
According to the granular solar cell performance measuring apparatus of claim 1, a reflective coating is formed on the inner surface of the spherical measuring chamber, and the light generated by the xenon lamp is filled in the entire measuring chamber and measured by the solar cell holding means. Since the granular solar cell held so as to be arranged at the center of the chamber receives light from all directions, the photovoltaic power of the solar cell can be measured by the photovoltaic power measuring means. Photovoltaic power can be generated according to the usage pattern in which the solar cell is actually used, and the photovoltaic performance of the solar cell can be evaluated.
[0030]
According to the granular solar cell performance measuring apparatus of claim 2, the same effect as that of the invention of claim 1 is basically obtained, and the xenon lamp is installed outside the main body case, so that the thermal load of the xenon lamp is reduced. This makes maintenance and inspection of the xenon lamp easier.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a granular solar cell performance measuring apparatus according to an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a spherical solar cell.
FIG. 3 is a cross-sectional view of a granular solar cell performance measuring apparatus according to a modified embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1, 1A Granular solar cell performance measuring apparatus 2 Measuring chamber 3 Solar cell 2a Reflective film 4, 4A Xenon lamp 10 Main body case 17 Control apparatus for measurement (photovoltaic measuring means)
18 Drive unit 19 Light guide

Claims (2)

In an apparatus for measuring the photovoltaic power by irradiating the solar cell with light in order to measure the photoelectric conversion performance of the granular solar cell,
A body case that can be opened and closed with a spherical measurement chamber formed inside,
A reflective coating formed on the inner surface of the measurement chamber;
A xenon lamp disposed so that a light emitting unit faces the measurement chamber;
A drive unit for electrically driving the xenon lamp;
Solar cell holding means for holding a granular solar cell in the center of the measurement chamber ; and
Photovoltaic measuring means electrically connected to the granular solar cell held by the solar cell holding means and measuring the photovoltaic power;
A granular solar cell performance measuring apparatus comprising: In an apparatus for measuring the photovoltaic power by irradiating the solar cell with light in order to measure the photoelectric conversion performance of the granular solar cell,
A body case that can be opened and closed with a spherical measurement chamber formed inside,
A reflective coating formed on the inner surface of the measurement chamber;
A light guide formed in the main body case in communication with the measurement chamber;
A xenon lamp that is disposed outside the main body case and supplies light to the measurement chamber via a light guide,
A drive unit for electrically driving the xenon lamp;
Solar cell holding means for holding a granular solar cell in the center of the measurement chamber ; and
Photovoltaic measuring means electrically connected to the granular solar cell held by the solar cell holding means and measuring the photovoltaic power;
A granular solar cell performance measuring apparatus comprising:

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