Resumen: Achieving the optimal design of power converters requires a deep understanding of the system's dissipation elements to meet the desired performance and safety standards. Once the power converter is designed, it is of key importance to estimate the actual power losses in the real setup, in order to redesign the power converter or monitor and control the semiconductor power losses. With that purpose, calorimetric techniques have outperformed electrical methods. However, they come with mechanical limitations and depend on analytical electrothermal equivalent circuits. These models are highly topology and technology dependent, often resulting in simplistic representations that underestimate thermal effects or complex sets of differential equations. To overcome these challenges, we present a novel post-design automatic method for characterizing semiconductor power losses through its converter thermal dynamics. Our method is rooted in an optimization program that identifies the optimal discrete-time linear model according to a set of power vs. temperature profiles. The proposed approach ensures accurate identification and integration of desired modeling requirements. The methodology is applicable to any power converter topology, and the derived linear model enables the use of standard control theory techniques for monitorization and control. Experiments with a real power converter validate the proposal's versatility and accuracy. Idioma: Inglés DOI: 10.1109/TPEL.2024.3412009 Año: 2024 Publicado en: IEEE Transactions on Power Electronics 39, 9 (2024), 11086-11098 ISSN: 0885-8993 Financiación: info:eu-repo/grantAgreement/CDTI MIG-20201042 CARDHIN Financiación: info:eu-repo/grantAgreement/ES/MCIU/FPU19-05700 Tipo y forma: Artículo (Versión definitiva) Área (Departamento): Área Ingen.Sistemas y Automát. (Dpto. Informát.Ingenie.Sistms.) Área (Departamento): Área Tecnología Electrónica (Dpto. Ingeniería Electrón.Com.)