Lifetime Analysis of Grid‐Tied Photovoltaic System Considering DC–DC Converter Ripple and Efficiency

ABSTRACT

This work conducts a lifetime analysis of a two‐stage grid‐tied photovoltaic (PV) system by addressing critical lifetime‐limiting parameters. In particular, it investigates the impact of input current ripple and actual operating voltage of the DC–DC converter on system reliability. To evaluate these effects, detailed assessments are conducted using mission profiles from two geographically and climatically distinct locations: Aalborg (Denmark) and Arizona (USA). The analysis reveals that input current ripple causes significant losses in the extracted PV power, reaching 6.72% in Aalborg and 4.65% in Arizona for the conventional boost converter. The effect is more pronounced in Aalborg due to frequent low‐irradiance operating conditions. Conversely, considering the actual operating voltage results in 28.5%–35.3% higher DC–DC converter losses than those predicted by conventional methods, with the impact being more significant in Arizona because of its higher irradiance levels. The resulting thermal stresses on power devices are validated using a hardware‐in‐the‐loop (HIL) platform and are further processed using rainflow counting, damage accumulation models, and Monte Carlo simulations to estimate component and system lifetimes. The results show that conventional approaches substantially overestimate system lifetime, whereas the proposed approach predicts B ₁₀ lifetimes of 22 years and 11 years for the interleaved boost converter‐based PV system in Aalborg and Arizona, respectively. These findings underscore the necessity of incorporating converter‐specific electrical and thermal stressors for accurate lifetime estimation of grid‐tied PV systems.