RECEIVER PLANE ILLUMINATION PROFILES – RAY TRACING AN EXTENTED LIGHT SOURCE THROUGH OPTICAL SYSTEMS WITH VARIABLE MISALIGNMENT PARAMETERS

摘要

An approach to simulate illumination patterns incident on the front face of a solar cell is presented. Theillumination patterns are generated by ray tracing an input solar profile through a system of lenses onto a receiver plane.The model allows the inclusion of solar tracking errors; component alignment and orientation errors; chromaticaberration; and spectrally dependent transmission losses. Realistic input flux distributions are achieved by treating theSun as an inhomogeneous extended light source. The resultant illumination pattern is formatted as a useful input to a 3Dsolid state physics model for the investigation of solar cell device performance. Generated illumination patterns are splitinto appropriate energetic bands according to user-defined multi-junction cell structures. The effects of chromaticaberration differ for each band due to the chromatic dependency of the lens refractive index, this can be seen in the bandseparated illumination patterns. The optical system modelled herein shows an illumination pattern displacement to lineartracking error relationship of 11.2mm per degree. Geometric concentration ratios are found to vary as much as 200%between multi-junction cell associated activation bands. Example illumination patterns are given throughout.