Power Semiconductor Ageing Test Bench Dedicated to Photovoltaic Applications

Abstract

This paper presents a new concept of semiconductor ageing test benches dedicated to photovoltaic inverters. The ageing profile is obtained by analyzing mission profiles of the current and the ambient temperature, extracted over several years from different photovoltaic plants. Accordingly, the ageing test is done by applying power cycling under variable ambient temperature, using power semiconductors in a pulsewidth modulation inverter and under nominal conditions. The measurement and estimation of power losses and thermal models are then used to choose the ageing profile parameters adapted to the experimental setup. Finally, the preliminary experimental results of the accelerated ageing tests are presented in the case of silicon carbide mosfets power semiconductors. These results show a remarkable increase in the gate-to-source threshold voltage, the leakage currents, and the drain-to-source on resistance.