Reliability Assessment of Power Electronic Converters in Renewable Energy Applications

Abstract

Power electronic converters provide essential interfaces between renewable energy sources, storage devices, and electrical networks. Their reliability affects energy production, maintenance expenditure, and continuity of electricity supply. This narrative review examines failure mechanisms and develops an integrated assessment framework connecting mission profiles, component stresses, lifetime models, condition monitoring, and maintenance decisions. Attention is given to electrothermal modeling, cumulative fatigue, probabilistic analysis, and the distinction between component lifetime and system availability. Topology selection, thermal management, fault tolerance, and limitations of laboratory-to-field extrapolation are discussed. An illustrative Weibull graph demonstrates the influence of assumed characteristic lifetime on survival probability; it does not represent experimental measurements. Credible assessment requires application-specific data, experimentally supported models, explicit uncertainty treatment, and operational validation. Integrating these elements can support defensible decisions about converter sizing, control, replacement, and renewable asset management.