This paper aims to assess the lifetime of a T-type active front end (AFE) converter in the context of Grid-to-Vehicle (G2V) and Vehicle-to-Grid (V2G) applications providing various grid services. To achieve this goal, the research paper presents two G2V and three V2G profiles and measures the junction temperature oscillations for the entire mission profile. Then, the temperature profiles are imported into a reliability assessment model to determine each mission profile's impact on the system's reliability.

High voltage GaN power transistors can significantly improve the key performance indices of a power electronic converter in terms of efficiency, reliability and power density. This brings a potentiality for widespread adoption of these semiconductors in e-mobility applications such as on-board chargers (OBCs) in electric vehicles. According to literature surveys, among all semiconductor technologies GaN-based high-electron-mobility transistors (HEMTs) devices are utilized to design compact, efficient and reliable OBCs. In this paper, a component-level (i.e., switch, capacitor and magnetics) optimization model is proposed based on Multi-objective Genetic Algorithm (MOGA) technique to assess the relationship between size (cm3), losses (W), and reliability (number of cycles) of the components used in OBCs. Besides, electrical circuit models establishing the relationship between these components for a dual-stage OBC architecture are presented. Finally, Pareto-front solutions for these components under the worst-case operation scenario are presented for the components used in the AC-DC stage of a bidirectional phase-modular three-phase OBC with a rated power of 11 kW.

In this paper, an advanced method for implementing active thermal control is proposed that can be helpful for smoothing repetitive junction temperature swing, which is one of the main reasons for wear-out failure in Wide bandgap (WBG)-based (i.e., SiC) power electronics converters (PEC). Utilizing current-source gate-drive, rise/fall (tON/tOFF) time during switching transition can be controlled, resulting in shaping switching losses in the form that can minimize junction temperature swings. The proposed method is implemented for an AC-DC converter and the simulation results validate the performance of the proposed method. It shows that by reducing junction temperature swing by 7°C, the lifetime of the PEC can be improved by a factor of 2.