WO2011033025A1

WO2011033025A1 - Method and arrangement for adjusting a solar simulator

Info

Publication number: WO2011033025A1
Application number: PCT/EP2010/063624
Authority: WO
Inventors: Ralf Adelhelm; Johannes Meier
Original assignee: Oerlikon Solar Ag, Trübbach
Priority date: 2009-09-16
Filing date: 2010-09-16
Publication date: 2011-03-24

Abstract

The present invention relates to a method for adjusting a solar simulator (12), particularly for adjusting the spectral exposure rate of a solar simulator (12). By means of the method according to the invention, the spectral exposure rate in particular can be adjusted very precisely, improving a subsequent measurement of a solar cell, for example, with respect to the opto-electronic properties thereof. The method comprises the steps according to the invention: a) disposing a solar simulator in a plane E1; b) disposing at least two detectors in a test plane E2, wherein the test plane E2 comprises a defined distance A1 to the plane E1, and wherein each of the detectors comprises a spectral sensitivity in a different spectral range; c) irradiating the at least two detectors with light of a wavelength range of 250 nm to 4 μm, particularly 300 nm - 1900 nm, particularly preferably 300 nm - 1200 nm; d) changing the distance A1 or adjusting the lamp power of the solar simulator such that the fist detector reaches a defined target value; e) checking the actual value of the second detector (18); f) reducing the distance A1 and lowering the lamp power of the solar simulator in the case where the impinging light has too short a wavelength, or increasing the distance A1 and raising the lamp power of the solar simulation in the case where the impinging light has too long a wavelength, and g) repeating the steps d) through f) in the case where the actual values of the detectors deviate from the target values thereof.

Description

description

Method and device for setting a solar simulator Technical field

The present invention relates to a method and an arrangement for adjusting a solar simulator. More particularly, the present invention relates to a method and apparatus for adjusting the optimal spectral irradiance of a solar simulator for measuring characteristics of multiple solar cells.

State of the art

The exact measurement of opto-electronic characteristics, such as

electric power or the current-voltage characteristic, of solar cells and solar modules with one or more pn junctions,

In particular, single, tandem or multiple solar cells, is for the

Characterization and quality control of photovoltaic elements of great importance.

The demand for high and highest measurement accuracy of the electrical characteristics of solar cells is on the part of the cell manufacturers as well as users of photovoltaics. Central difficulty is the generation and measurement of optical radiation in a suitable solar spectral range.

For measuring the electrical power and other opto-electrical or opto-electronic characteristics of photovoltaic elements solar simulators are used to generate a radiation as a substitute for solar radiation. A typical commercial pulsed solar simulator, also referred to as a "flasher", is often powered by a pulsed xenon lamp.

Solar simulators or solar simulators with continuous irradiation or pulsed irradiation of solar cells are commercially available. The requirements regarding the temporal and spatial homogeneity of the irradiance as well as the requirements for the spectral irradiance are classified, for example, in IEC 60904-9. The selection of the optimum performance of a xenon lamp is subject to many criteria, which are determined primarily by the properties of the lamp itself during manufacture. In pulsed operation of the lamp results in the nominal irradiance at a nominal and fixed distance. Thus, lamp power and nominal distance are determined by specifying an irradiance or by specifying a reference detector. Typically, the power of the xenon lamp is determined by the voltage of the charging capacitors, whereby the setting of the charging voltage is the default of the lamp power. Also finds a power electronics for controlling the lamp power their use. Furthermore, the lamp power can be controlled during the pulse, which is done by means of a radiation detector with a setpoint, such as by reference solar cells according to IEC60904-2. Thus, the irradiance of the lamp is kept constant.

Generally speaking, the exact replica of the solar spectrum is problematic. The technical simulation of a reference spectrum by means of a solar simulator according to the prior art thus has no satisfactory quality. Even the most complex optical concept of a solar simulator, which is based on the filtering of radiation, is limited by the optical transmission and reflectance of the filters used. The transmission and reflection levels of all optical filters are characterized by their filter-typical band properties, which typically have no correlation to the spectral sensitivities of the solar cells or to the spectral characteristics of the reference spectra.

This systemic inaccuracy of the filter results in a

Uncertainty of the actual test object, the solar cell or the solar module, which can significantly reduce the accuracy of performance measurements in particular of multiple solar cells.

Presentation of the invention

It is therefore the object of the present invention, a method and an arrangement for adjusting the spectral irradiance of a To provide solar simulator with which the measurement of specific characteristics of a solar cell, in particular the electrical power or the current-voltage characteristic, is precisely and easily feasible.

This object is achieved by a method according to claim 1 and an arrangement according to claim 7. Particularly preferred

Embodiments are specified in the subclaims.

[001 1] The present invention relates to a method for adjusting a

Solar simulator, in particular for adjusting the spectral

Irradiance of a solar simulator, comprising the steps:

a) arranging a solar simulator in a plane Ε-ι;

b) arranging at least two detectors in a test plane E2, wherein the test plane E2 has a defined distance A1 to the plane Ei, and wherein the detectors have a spectral sensitivity in a respective different spectral range;

c) irradiating the at least two detectors with light of one

Wavelength range from 250nm to 4μηη, especially 300nm-1900nm, more preferably 300nm-1200nm;

d) changing the distance A1 or adjusting the lamp power of the solar simulator such that the first detector reaches a defined setpoint value;

e) checking the actual value of the second detector (18);

f) decreasing the distance A1 and decreasing the lamp power of the solar simulator in case the irradiated light is too short, or increasing the distance A1 and increasing the lamp power of the solar simulator in case the irradiated light is too long, and

g) repeating steps d) to f) in the event that the actual values of the detectors deviate from their nominal values.

The inventive method is based on an iterative approximation of the distance between the at least two detectors to the solar simulator and at the same time from the lamp power of the solar simulator until the actual values of the spectral measured by all detectors

Irradiance correspond exactly to the desired setpoints. The Setting is therefore according to the invention in particular a calibration of the solar simulator.

The inventive method is characterized in particular by the use of at least two spectrally selective

Reference detectors. These detectors each have a selectivity in a different spectral range. One of the detectors is selectively in a relatively high-energy or short-wave spectral component and can also be referred to as a blue component cell. Another detector is selective in one

relatively low-energy, or long-wave spectral component and can also be referred to as a red component cell.

The two detectors or component cells are

expediently with calibration values, ie setpoints, to be equipped with regard to the reference spectrum (IEC60904-2, -4).

In the method according to the invention, it is assumed that the actual values of the two detectors or their respective spectral irradiance deviate from the desired desired values. The nominal values are in particular data output by the detectors, such as a voltage corresponding to the desired values of the spectral irradiance. Typically, target and actual values are a few percent apart.

By measuring the two detectors, the discrepancy between the desired values with respect to the reference spectrum and the actual values under the simulator spectrum can be determined.

The inventive method uses the properties of the

power-dependent spectral course of the lamp or the illumination device of the solar simulator.

It is exploited that in lighting devices

or lamps in solar simulators near the nominal operating current of the lamp, the spectral irradiance in the relative course remains largely constant. In contrast, the change in the electrical power of a lamp is associated with the change in the spectral curve. This means a change in the relative spectral Irradiance. Thus, the increasing electric current density in the lamp with the increase of the short-wave component in the spectrum

to be watched. Qualitatively, for the visible light that

physical law of Wienschen shift to higher

Color temperature can be detected at higher lamp power.

The method begins at a nominal distance between the

Solar simulator, or between the lamp of the

Solar simulator, and the detectors, and a nominal power of the lighting device of the solar simulator. The nominal values are given by defined initial values, which are dependent, in particular, on the selected solar simulator or the lamp used in the solar simulator and the detector used.

The detectors with light of a wavelength in a range of 250nm to 4μηη, in particular 300nm-1900nm, more preferably 300nm-1200nm, irradiated. Such radiation can imitate the natural solar radiation particularly well and thereby make the measurements obtained particularly accurate.

Starting from these nominal values, the iterative approximation of the distance between the solar simulator and the detectors or the lamp power begins. For this purpose, the desired value of a detector is first set, before the desired value of the second detector is approximated via a variation of distance and lamp power. These steps are repeated until both detectors have their

Have reached setpoints. Typical changes of

Process parameters are on the order of 10% of the nominal distance and 10% of the lamp power.

Background of the method is always an increase in the

short-wave compared to the long-wave spectral component by increasing the power with a concomitant increase in the distance to

To achieve compensation of the irradiance or a reduction of the shortwave versus the longwave spectral range by reducing the power with concomitant reduction of the

Distance to compensate for the irradiance to achieve. Since the change in the relative spectral irradiance

is decisive, corresponds to the increase or decrease of the short-wave compared to the long-wave spectral range equally lowering or increasing the long-wave compared to the short-wave spectral range. The absolute spectral irradiance is given by the correct distance. It is therefore freely selectable, whether in the step d) is started with the short-wave detector, ie with the blue component cell, or with the long-wave detector, ie with the red component cell.

Due to the use of at least two detectors is

inventive method in a particularly suitable manner for

Adjustment of the spectral irradiance of a preferably pulsed solar simulator for the measurement of solar cells and solar modules with at least two active transitions suitable. The inventive method is particularly for a subsequent measurement of

Multiple solar cells, such as tandem solar cells suitable. With the method according to the invention, in particular the optimal

Adjustment of the spectrum of the solar simulator for photovoltaic elements with two transitions can be found.

Multiple solar cells or tandem solar cells comprise two solar cells, or partial cells, which are stacked in particular monolithically one above the other. The individual subcells are optimized for a specific wavelength range. In this way, a wider spectrum of sunlight can be absorbed, which increases the efficiency of the multiple solar cells.

In the case of multiple solar cells, in particular tandem modules

(tandem junction), an additional, special spectral adjustment is required in addition to the simulation of a reference spectrum:

The (resulting) spectrum of the solar simulator should generate the same currents in the individual sub-cells of a multiple solar cell as is the case under the reference spectrum. This is particularly due to the serial interconnection of the multiple solar cells or the sub-cells. As the individual streams are usually not on the test object are measurable, since the tandem cells are produced as a stack of semiconductor layers that are no longer individually accessible, special radiation detectors are used, which have approximately the spectral sensitivity of the individual sub-cells of a multi-junction solar cell.

This requirement is met by providing at least two detectors, wherein the number of detectors can be adapted to the number of sub-cells.

For simplicity, according to the invention all eligible radiation receivers are summarized below under the term "solar cell", even if, for example, the receiver is not based on the photovoltaic effect or, for example, only in combination with other devices, the electrical parameters are measurable.

The pertinent limits of this method are often given in particular by the variability of the spectral response as a function of the available electrical power range of the lamp and in the acceptable inhomogeneity in the test plane, which in many cases increases with decreasing distance, similar to a point light source.

In the context of an advantageous embodiment of the invention

Method, the solar simulator is used with a filter that is adapted to a reference spectrum. As a result, the spectral distribution of the lamp is already adapted to the solar reference spectrum, such as typically AM1.5 global, which is why only minor inaccuracies have to be eliminated by the method described. In other words, the actual values of the detectors are already close to theirs

Setpoints. Transmission filters are particularly preferably used here. The inventive method is then particularly effective and time-saving feasible.

In the context of a further advantageous embodiment of

According to the method of the invention, the distance Ai is changed by displacing the solar simulator relative to the test plane Ei. These

Design is particularly simple and possible without disproportionately high expenditure on equipment. In the context of a further advantageous embodiment of the method according to the invention, the distance Ai is changed by a displacement of the detectors relative to the solar simulator. These

Embodiment is particularly advantageous for industrial application. It is particularly possible to design the possibility of displacement as part of a feeding device, which not only the solar simulator is adjustable by the method, but also the solar cell to be measured can be measured in a few steps.

In the context of a further advantageous embodiment of the

The method according to the invention is the solar simulator with a

Neutral density filter used. A combination of a neutral density filter with the method according to the invention increases the adjustment possibilities and makes the inventive method significantly more flexible.

The invention further relates to a method for measuring an object, in particular a solar cell, comprising the steps:

- Setting the solar simulator according to an inventive

Method using a neutral density filter Ni with a transmission of in particular 95% and measuring the object,

- Setting the lamp power of the solar simulator to a defined setpoint of a detector using a neutral density filter N2, wherein the neutral density filter N2 has a transmission which is lower than that of the neutral density filter N- | , in particular of 90%, and remeasuring the object,

Setting the lamp power to a defined nominal value of another detector using the neutral density filter N2 and re-measuring the solar cell,

- Setting the lamp power to the setpoint of the first detector without neutral density filter and remeasuring the object, and

- Setting the lamp power to the setpoint of the other detector without neutral density filter and remeasuring the object.

This method is used to characterize the object with respect to the sensitivity of a spectral variation and provides information about the interaction of the two sub-cells in the object. The object is here in particular a multiple solar cell.

The invention further relates to an arrangement for adjusting a

Solar simulator, in particular for adjusting the spectral

Irradiance of a solar simulator comprising a

Solar simulator having a lighting device, with the light in a Wellenlenge of 250nm to 4μηη, in particular 300nm-1900nm, more preferably 300nm-1200nm, can be generated, and further

comprising at least two detectors which are selective for light of a respective different wavelength within the generated light, and which are arranged in a test plane E2 at a distance A1 from the plane E 1 of the solar simulator, wherein the distance A1 is variable.

With such an inventive arrangement, the advantages explained with reference to the method according to the invention can be achieved.

In the context of a preferred embodiment of the arrangement according to the invention, the solar simulator has a xenon lamp as

Lighting device on. A xenon lamp is particularly suitable for producing light or radiation with a spectrum that is particularly similar to that of sunlight. The setting of the

Solar simulator is so particularly suitable with respect to a subsequent measurement of an object, in particular a solar cell.

Particularly preferably, the xenon lamp is a

Short-arc high-pressure xenon lamp, or a long-arc low-pressure xenon lamp, also known as a flasher.

In the context of another preferred embodiment of

The arrangement according to the invention further comprises the arrangement

Recording for an object to be measured, in particular for a

Solar cell up. This makes it possible that in direct connection to the setting of the solar simulator, the object to be measured, in particular a solar cell, can be measured. As a result, the arrangement is self-sufficient and also suitable for a particularly time-saving measurement of the solar cell.

In the context of another preferred embodiment of According to the invention arrangement, the solar simulator for changing the distance Ai designed to be displaced. This embodiment is particularly simple and possible without disproportionately high expenditure on equipment.

In the context of another preferred embodiment of

According to the invention arrangement, the at least two detectors for changing the distance Ai designed to be displaced. These

Embodiment is particularly advantageous for industrial application. It is particularly possible to design a displacement means as part of a feeding device, which not only the solar simulator is adjustable with the method, but also the solar cell to be measured can be measured in a few steps.

In the context of another preferred embodiment of

According to the invention arrangement, the at least two detectors are arranged orthogonal to the optical axis of the light generated by the illumination device or the generated radiation. In this embodiment, particularly good results with respect to the accuracy of the adjusted spectral irradiance can be achieved.

In the context of a further advantageous embodiment of

The arrangement according to the invention is a linear displacement for the solar simulator and / or for the at least two detectors for

Changing the distance Ai provided. This is a particularly simple and reliable possibility of shifting the solar simulator and / or the detectors, with the smallest displacements even further accurate and reproducible feasible.

In the context of a further advantageous embodiment of

Inventive arrangement, the solar simulator has a

Neutral density filter on. In particular, the neutral density filter has a transmission of 90% or 95%.

Brief description of the drawings

The articles of the invention will be described with reference to others

Advantages and advantageous embodiments of the figures

illustrated and explained in the following description. there It should be noted that the figures are only descriptive and are not intended to be in any way invention

limit.

In the drawings:

1 shows a process diagram of the method according to the invention, and [0049] FIG. 2 shows an arrangement according to the invention for setting a

Solar simulator.

Detailed description of the drawings

In Figure 1, the inventive method is based on a

Process Schemes shown.

According to the invention, it is assumed that the actual values of the

at least two detectors and thus those of the

Lighting device generated radiation deviate from the desired conditions or setpoints, which is why the

Adjustment of the solar simulator, in particular the adjustment of the spectral irradiance of the solar simulator, is necessary.

[0052] According to FIG. 1, the method according to the invention starts with a

nominal distance between the solar simulator and the at least two detectors. It radiates the lighting device of the

Solar simulator comprising the lamp head, that means the lamp with any optics with housing, leads and brackets, also with a nominal lamp power.

The nominal distance can typically be several decimetres up to

be several meters, whereas the nominal light intensity with a particular 1000W / m ² on a test area of the size of a

Solar cell, especially in the range of one or more

Square-decimeter, or a solar module, in particular in the range of one or more square meters, with a homogeneous distribution. The lighting device can be designed in particular as a so-called flasher. This means that the generated light or the generated radiation is generated in the form of temporally limited flashes. The plateau of the radiation is in particular in the order of milliseconds.

In the following, the distance of a detector to the solar simulator or to the lamp head of the solar simulator is varied until, for example, the detector selective for high-energy radiation, ie the blue component cell, reaches its desired value. Alternatively, the blue component cell or its actual value can be used to regulate the lamp power to the set value of the blue

Reach component cell.

Now, in addition to the blue component cell also for low-energy radiation selective detector, ie the red

Component cell, measured. Reach both detectors

or component cells their setpoint, the process is completed, the solar simulator is set as desired

or calibrated.

However, if the actual value of the red component cell is below the desired value or nominal value, this means that the spectral

Distribution towards shortwave wavelengths starting from the

Setpoints is shifted, so the light is too short-waved. In this case, the power of the lamp is to be reduced and the distance Ai must be shortened, in particular between two flashes of the designed as a flasher solar simulator. The reduction of lamp power and distance Ai are geared appropriately to the discrepancy between the setpoint and the actual value.

On the other hand, if the actual value of the red component cell is above that

Target value, this means that the spectral distribution is shifted towards long-wave wavelengths starting from the setpoints, so the light is too long-waved. In this case, increase the power of the lamp and increase the distance. The increase of

Lamp power and distance are expediently based on the discrepancy between setpoint and actual value.

The change in the lamp power is inventively accompanied by the change in the distance between the solar simulator and the detector or the detectors. Now both detectors are measured again. If both detectors measure their setpoints, the procedure is completed.

If the desired values are not available, the method is started again to set the desired value of a detector. Repeating these steps will result in an iterative change in the distance or lamp power, respectively, until both the red and blue component cells, both detectors, have reached their setpoints.

It can be seen that the method described above can be performed equally when the red and the blue component cell are reversed, so with the setting of the distance of the red

Component cell is started.

Since the inventive method a change in the distance

between the lamp head and the test level, the centered and orthogonal orientation of the

Test object to the optical axis of the system to be checked.

In one development of the method according to the invention, an object to be measured, such as a solar cell, can be measured using a neutral density filter (NDF). Suitable measuring objects are all radiation receivers for optical radiation of the range of solar radiation in which measurable changes in the electrical properties are caused by absorption of the optical radiation.

The irradiance can be in the test level E | , so at a distance Ai be changed by neutral density filter. In commercial flashers neutral density filters are already available, which allow a gradual attenuation of the irradiance without affecting the relative spectral irradiance.

The combination of neutral density filters (NDF) with the

inventive method increases the setting options: In principle, when using the neutral density filter and constant distance, the lamp power can be increased, which leads to an increase of the short-wave spectral component. Alternatively, at the same

Lamp power the distance can be shortened. Preferably, two neutral density filters with a transmission of 95% (NDF95) and 90% (NDF90) are used as follows to examine a photovoltaic object with two junctions, in particular a tandem solar cell, of course

Neutral density filters with different transmission values are possible:

Using the neutral density filter with a transmission of 95%, the method according to the invention for approximating the reference spectrum is used and the object is measured under these conditions, generally under standard test conditions.

In a next step, using only the

Neutral density filter with a transmission of 90%, the lamp power to the nominal value of a detector or one of the

Component cell adapted and performed a second measurement on the object to be measured. A third measurement provides the

Adjustment of the lamp power to the second component cell.

Subsequently, without using a neutral density filter, the

Lamp power adjusted to the desired value of the first detector or the first component cell, after which the test object is measured a fourth time. A fifth measurement is made at the lamp power matched to the second component cell.

This method is used to characterize the to be measured

Object, ie in particular the tandem solar cell with regard to the sensitivity of a spectral variation and provides information about the interaction of the two sub-cells in the test object.

Essential technical component of this invention

Measuring method is the gradation of irradiance below

Use of at least two neutral density filters which, under at least three lamp powers, provide an approximately equidistant positive and negative change in the setpoint value of at least one component cell, which means, for example, the setpoint +/- 5%.

An inventive arrangement 10 for performing the

The method according to the invention is shown in FIG.

According to FIG. 2, the arrangement 10 comprises a solar simulator 12, which in FIG a level egg is arranged. The solar simulator 12 includes a lamp or lighting device 14. Die

Illumination device 14 is suitable for generating light in a wavelength of 250 nm to 4 μm, in particular 300 nm-1900 nm, particularly preferably 300 nm-1200 nm. Particularly preferably, the

Lighting device 14, a xenon lamp, and this and thus the solar simulator 12 may be formed as a flasher or flash simulator.

The arrangement 10 further comprises at least two detectors 16, 18, which may be configured as reference solar cells or reference solar modules. The detectors 16, 18 are selective for light of a different wavelength. For example, the detector 16 is selective for comparatively short wavelength light and is therefore referred to as a blue component cell, whereas the detector 18 is selective for comparatively long wavelength light and therefore red

Component cell is called.

Particularly preferably, the solar simulator 12 comprises a filter adapted to the reference spectrum so as to already obtain an approximate simulator spectrum.

The detectors 16, 18 are arranged at a distance Ai from the solar simulator 12 or its illumination device 14. Preferably, the detectors 16, 18 are further arranged orthogonal to the optical axis of the radiation generated by the illumination device 14.

According to the invention, it may be provided that the solar simulator 12 and / or the two detectors 16, 18 are designed to be displaceable. In this regard, first, a mechanically reproducible

Distance change and secondly to achieve a precise alignment of the detectors 16, 18, at least one mechanical lateral

Linear displacement for the solar simulator 12 and its illumination device 14 or for a holder of the detectors 16, 18 may be provided. The linear displacement devices are preferably fixed in a floor or ceiling of the arrangement anchored so that all distances are reproducible. An electromechanical drive of the linear displacement offers corresponding advantages.

It is also advantageous if the arrangement 10 further comprises a receptacle for an object to be tested, in particular for a solar cell.

This can be done in a next step after setting the

Solar simulator 12 directly take a measurement of an object, such as a solar cell.

The individual combinations of the constituents and the features of the already mentioned embodiments are exemplary; the exchange and substitution of these teachings with other doctrines taught in this

Document are included with the cited references are also expressly considered. Those skilled in the art will recognize that variations, modifications and other implementations described herein may also occur without departing from the spirit and scope of the invention.

Accordingly, the above description is illustrative and not restrictive. The word used in the claims does not exclude other ingredients or steps. The indefinite article "a" does not exclude the meaning of a plural The mere fact that certain measures are recited in mutually different claims does not make it clear that a combination of these measures can not be used to advantage the following claims are defined and the

associated equivalents.

Claims

claims

1. A method for setting a solar simulator (12), in particular for

Adjusting the spectral irradiance of a solar simulator (12) comprising the steps of:

a) arranging a solar simulator (12) in a plane Ε-ι;

b) arranging at least two detectors (16, 18) in a test plane E2, wherein the test plane E2 has a defined distance A1 to the plane Ei, and wherein the detectors (16, 18) have a spectral sensitivity in a respective different spectral range;

c) irradiating the at least two detectors (16, 18) with light of a

d) changing the distance A1 or adjusting the lamp power of the solar simulator (12) such that the first detector (16) reaches a defined setpoint value;

e) checking the actual value of the second detector (18);

f) decreasing the distance A1 and decreasing the lamp power of the solar simulator (12) in case the irradiated light is too short, or increasing the distance A1 and increasing the lamp power of the solar simulator (12) in case the irradiated light increases is longwave, and

g) repeating steps d) to f) in the event that the actual values of the detectors (16, 18) deviate from their nominal values.

2. The method according to claim 1, characterized in that the solar simulator (12) is used with a filter which is adapted to a reference spectrum.

3. The method according to claim 1 or 2, characterized in that the

Distance A1 by shifting the solar simulator (12) relative to the

Test level egg is changed.

4. The method according to any one of claims 1 to 3, characterized in that the distance A1 by a displacement of the detectors (16, 18) relative to the solar simulator (12) is changed.

5. The method according to any one of claims 1 to 4, characterized in that the solar simulator (12) is used with a neutral density filter.

6. A method for measuring an object, in particular a solar cell, comprising the steps:

- Setting the solar simulator (12) according to a method according to claim 5 using a neutral density filter Ni with a transmission of in particular 95% and measuring the object,

- Setting the lamp power of the solar simulator (12) to a defined setpoint of a detector (16) using a neutral density filter N2, wherein the neutral density filter N2 has a transmission which is lower than that of the neutral density filter N- | , in particular of 90%, and again

Measuring the object,

Adjusting the lamp power to a defined desired value of another detector (18) using the neutral density filter N2 and re-measuring the solar cell,

Adjusting the lamp power to the nominal value of the first detector (16) without neutral density filter and remeasuring the object, and

- Setting the lamp power to the target value of the other detector (18) without neutral density filter and remeasuring the object.

7. Arrangement for setting a solar simulator (12), in particular for

Adjusting the spectral irradiance of a solar simulator (12) comprising a solar simulator (12) having an illumination device (14), with the light in a Wellenlenge 250nm to 4μηη, in particular 300nm-1900nm, more preferably 300nm-1200nm, is generated, and further comprising at least two detectors (16, 18), which are selective for light of a different wavelength, respectively, within the generated light and which are arranged in a test plane E2 at a distance A1 from the plane Ei of the solar simulator (12) the distance A1 is changeable.

8. Arrangement according to claim 7, characterized in that the

Solar simulator (12) has a xenon lamp as a lighting device (14).

9. Arrangement according to claim 7 or 8, characterized in that the

Arrangement (10) furthermore a receptacle for an object to be measured, in particular for a solar cell.

10. Arrangement according to one of claims 7 to 9, characterized in that the solar simulator (12) is designed to change the distance Ai displaced.

1 1. Arrangement according to one of claims 7 to 10, characterized in that the at least two detectors (16, 18) are designed to change the distance A 1 displaced.

12. Arrangement according to one of claims 7 to 1 1, characterized in that the at least two detectors (16, 18) are arranged orthogonal to the optical axis of the light generated by the illumination device (14).

13. Arrangement according to one of claims 7 to 12, characterized in that a linear displacement for the solar simulator (12) and / or for the at least two detectors (16, 18) is provided for varying the distance Ai.

14. Arrangement according to one of claims 7 to 13, characterized in that the solar simulator (12) has a neutral density filter.

15. Arrangement according to claim 14, characterized in that the

Neutral density filter has a transmission of 90% or 95%.