Sun simulator
A sun simulator is a technical device used to simulate natural sunlight . It is used to investigate the effects of light on certain objects to be irradiated, even under laboratory conditions .
Since natural sunlight is subject to strong temporal fluctuations, the use of a sun simulator has the advantage over field tests that measurements can be carried out and reproduced under defined, continuous conditions that are independent of the day and season.
The disadvantage is the increased expenditure on equipment, the increased investment, operating and maintenance costs and the difficulty of finding a suitable light source that reproduces the sunlight spectrum as precisely as possible.
Areas of application
Examples of the use of solar simulators are:
- Plant experiments under controlled environmental conditions
- Growing plants in greenhouses
- Measurement of the total energy transmittance of large-area transparent components, glazing, sun protection devices, etc. Ä.
- Light therapy in medicine
- Investigation of the performance of solar cells , see here
- Investigation of the performance of solar collectors
- Simulation of the light aging behavior of amorphous solar cells ( degradation )
Sun simulators in photovoltaics
In the field of photovoltaics, a distinction is made between the pulsed (or flash simulator) on the one hand and the continuous (or stationary) simulator on the other. Requirements for solar simulators in photovoltaics are specified in the IEC 60904-2 standard.
Flash simulator
The flash simulator is particularly suitable for investigating the performance of solar cells, i.e. H. for recording current-voltage characteristics . With a relatively low electrical connection load , a very high irradiance can be achieved. Due to the short-term irradiation, the heating of the object to be measured, the filter and the environment is usually negligible.
Continuous simulator
The continuous simulator is suitable for investigating the light aging behavior of amorphous solar cells ( degradation ). The advantage of this simulator is its simple, inexpensive and robust structure. It is also suitable for materials with longer response times , such as thin-film cells made of amorphous silicon , which have a higher capacity than cells made of crystalline silicon. The comparatively high power consumption and the warming of the environment have a disadvantageous effect.
Other distinguishing features
Further distinguishing features for solar simulators in the field of photovoltaics are:
size
The size of the recording unit for the objects to be irradiated ranges from a few square centimeters (one cell ) to several square meters (several modules ).
accuracy
According to their performance , solar simulators are divided into accuracy classes (Class A, B and C). The performance requirements for simulators in the different accuracy classes are specified in the standard with the designation IEC 60904-9.
Light source
The spectrum most similar to the reference solar spectrum AM 1.5 has xenon lamps , followed by metal halide lamps . Halogen lamps are cheaper, but only suitable to a limited extent for use in solar simulators in the field of photovoltaics.
literature
- Heading for a longer light pulse, market survey on solar simulators for PV modules . In: PHOTON International , 6, 2007, p. 158 (overview of the solar simulators currently available on the market for use in photovoltaics).
Web links
- Research and test center for solar systems, Institute for Thermodynamics and Thermal Engineering (ITW) of the University of Stuttgart.
Individual evidence
- ↑ International Electrotechnical Commission [IEC] (Ed.): IEC 60904-2: Photovoltaic devices - Part 2: Requirements for reference solar devices . 2007.