Spatially distributed model for the analysis of laser beam induced current (LBIC) measurements of thin film silicon solar modules

• Published in: Solar energy materials and solar cells 2011, Vol.95 (1), p.111-114
• Main Authors: Vorasayan, P., Betts, T.R., Gottschalg, R.
• Format: Article
• Language: English
• Subjects: Applied sciences; Computer programs; Direct energy conversion and energy accumulation; Distributed model; Electrical engineering. Electrical power engineering; Electrical power engineering; Energy; Exact sciences and technology; Homogeneity; LBIC; Modules; Natural energy; Photoelectric conversion; Photovoltaic cells; Photovoltaic conversion; Sensitivity analysis; Solar cells; Solar cells. Photoelectrochemical cells; Solar energy; Thin film; Thin films; Three dimensional
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2010.02.020

A 3D distributed model is developed and implemented based on circuit analysis software for the investigation of spatial variation in performance due to the distributed nature and non-uniformity of solar cell properties. This is applied to LBIC measurements where it is used for sensitivity analysis of the measurements with respect to certain parameters in series connected thin film PV modules. The model is used to explain the differences in dark and illuminated measurements, which clearly shows the illuminated LBIC signal is largely dependent on the homogeneity of the background illumination. The dark LBIC is largely affected by the shunt resistance of the neighbouring cells rather than by the signal strength of the cell under test. It is required to bring the cell into limiting conditions, which then gives a signal one order of magnitude stronger than that in the non-limiting case. The simulations are validated against measurements taken in these regimes.