Impact of the mission profile length on lifetime prediction of PV inverters

The first step of the design for reliability (DFR) approach in PV inverters is the translation of the mission profile into thermal loading. Most works employ only a one-year mission profile even though it is known that it changes year to year due to climatic reasons and randomness of cloud behavior. This work evaluates how mission profile length affects the system-level reliability of a 5.5 kW PV inverter. Different mission profile lengths (1-5 years) are compared to the typical average year (TAY) mission profile. The results indicate that the use of 1 year mission profile affects by 7% the estimated inverter B-10 lifetime.