login

Search documents

Browse topics

Document details

 
Title:
 
Long Term Degradation of c-Si PV Module Analyzed by IV Curve Fitting
 
Author(s):
 
L. Abenante, F. De Lia, A. Mittiga
 
Keywords:
 
Degradation, Performance, Modelling / Modeling, PV Module
 
Topic:
 
COMPONENTS FOR PV SYSTEMS
Subtopic: PV Modules
Event: 28th European Photovoltaic Solar Energy Conference and Exhibition
Session: 4AV.5.32
 
Pages:
 
3284 - 3288
ISBN: 3-936338-33-7
Paper DOI: 10.4229/28thEUPVSEC2013-4AV.5.32
 
Price:
 
 
0,00 EUR
 
Document(s): paper
 

Abstract/Summary:


Long term c-Si module degradation can be due to many different physical mechanisms. To discriminate among them, we have exploited the light IV curves of six modules measured at different stages during 30 years of module outdoor exposure. To make them comparable, these curves have to be corrected for irradiance and temperature effects. Since this procedure requires the knowledge of the module series resistance, RSER, value, “pseudo-dark” IV-curves, obtained by subtracting the photocurrent value from the measured light IV curves, are previously fitted with an iterative approach using the two diodes model including RSER and shunt resistance, RSH, effects. Applying the same fitting approach to the “pseudo-dark” IV-curves obtained from the corrected light IV-curves allows performing a comparison among the values of performance and cell parameters at three different exposure times. For each module, the most significant variations appear to occur in the fill factor, FF, and RSER values. These variations are not linear with aging time and the FF variations are inversely correlated to the variations in the RSER value.