Mission-Profile-Aware Physics-of-Failure Reliability Assessment and Quantitative FMEA of a 10 kW Solid-State Transformer

Solid-state transformers (SSTs) are pivotal for next-generation power systems, yet their widespread adoption is hindered by reliability uncertainties under diverse operational conditions. This paper introduces a mission-profile-aware, physics-of-failure (PoF) reliability assessment framework that explicitly links operating conditions, degradation mechanisms, and statistical uncertainty. The approach combines PoF models for stress-sensitive components with handbook-based reliability models for passive elements, employing Joint Electron Device Engineering Council (JEDEC)-aligned statistical methods for failure rate extraction. Quantitative failure-in-time (FIT) estimates are integrated into a physics-informed Failure mode and effects analysis (FMEA), replacing subjective occurrence rankings with FIT-derived quantitative occurrence ratings while retaining explicit severity and detection criteria. The framework is demonstrated on a 10 kW Type-IV SST across multiple mission profiles and ambient temperatures. The results reveal that the system-level mean time between failures (MTBF) varies from 4.6 to over 8 years, with gate-driver electronics and DC-link capacitors dominating FIT contributions. Mission-dependent shifts in failure mechanisms highlight the inadequacy of single MTBF metrics. This scalable framework provides a foundation for reliability-oriented SST design, qualification, and deployment.