Development and testing of a Sr-measurement system for integration in an existing vertical I-V-measurement system

Abstract

The aim of this work was to evaluate different methods for Sr-measurement and to de- velop and construct a measurement system which can be integrated inside a vertical I-V- measurement system and be used for the measurement of commercial sized PV-modules at AIT Austrian Institute of Technology GmbH. In addition the Sr-measurement system is supposed to perform a measurement according to the standard IEC 60904-8. The most promising possibilities for achieving quasi-monochromatic light are shortly discussed in this work. Afterwards the developed Sr-measurement system is introduced and the different com- ponents are explained. This system is based on optical bandpass filters, used for producing quasi monochromatic light and the lamp used for illumination is a Xenon flasher. Achieving a large area with homogeneous irradiation within ±2 % is impossible with this set-up as it is, only ±5 % can be achieved for large area modules. Very small modules can be measured under the strict conditions for homogeneity. In addition, leaking white light is disturbing the Spectral Response-measurement, thus overcoming any other measurement error. There- fore, the system can not yet be used for a serious Spectral Response-measurement and for measurements under normative regulations. However, this system is a first prototype which has to be and can be improved. Furthermore, this system has potential to be extended, e.g. for use with other PV-module technology such as multi-junction devices after installing coloured bias light.