Optical and electrical characterization of high-concentration photovoltaic systems= Caracterización óptica y eléctrica de sistemas fotovoltaicos de alta concentración

摘要: The record efficiencies achieved by multijunction (MJ) solar cells have renewed the interest in concentrator photovoltaics (CPV), as the use of high concentration is necessary to reduce the area of these expensive devices and to maximize their efficiency. The promise is a reduction of the cost of the electricity generated as compared to flat plate PV. In order to improve the efficiency of these systems, intensive research is being carried out regarding concentrator cells, optics and integration of systems. Characterization tools are also essential for the development and optimization of concentrators, from the development of the initial prototypes to the manufacturing line. However, there is a poor knowledge of appropriate characterization tools for CPV systems and their elements. Furthermore, the lack of indoor testing procedures may be a bottleneck to the large-scale production of CPV modules and a barrier to their commercial deployment. This thesis contributes to the development of instruments and methods for the indoor characterization of high-concentration PV systems and their constituent elements. Primarily, a solar simulator able to measure CPV modules has been designed and developed (probably the first in the world), which constitutes the cornerstone instrument for the indoor characterization methods developed. The key component of the illumination system of the solar simulator is a large-area collimator mirror with a long focal distance, which collimates the light coming from a small flash light source placed at its focus. An investigation of those manufacturing techniques that feature a relatively low cost and sufficient optical quality has been …