Moumita Naskar
Cable and Diagnostics Division, Central Power Research Institute, Bangalore – 560080, Karnataka
H. M Dharmendra
Cable and Diagnostics Division, Central Power Research Institute, Bangalore – 560080, Karnataka
K. P. Meena
Cable and Diagnostics Division, Central Power Research Institute, Bangalore – 560080, Karnataka
Abstract
A rapid test method based on a logarithmic degradation model for the lifetime assessment of ethylene-vinyl acetate (EVA) used as encapsulants in Photovoltaic (PV) module is proposed. In general, encapsulants are used in widely varied conditions. However, factors such as voltage stress, irradiation, mechanical shock and vibration, environmental conditioning and chemical contamination should be evaluated. In the present study evaluation is carried on the dumbbell specimens of encapsulating material itself and is based on the percentage of reduction in the property i.e elongation percentage, which is a destructive test. Dumb-bell specimens as per ISO 37:2011(E) standard are employed. Adequate number of test specimens were subjected to thermal aging at three different temperatures 35 °C, 45 °C and 55 °C. The conditioned specimens after removing from oven were stored in decicator prior to testing i.e. while the specimens were attaining room temperature. The constant factors of the life time line a and b were calculated, and finally, the lifetime values were estimated.