Developing mission profiles for lifetime assessment of bidirectional AC charging on electric vehicle power electronics

The bidirectional charging of electric vehicles offers new opportunities to create value streams that can reduce total cost of ownership. While research has largely focused on high-voltage battery aging, less attention has been paid to power electronic components, such as the onboard charger, whose premature failure can result in substantial repair costs. This study develops high-fidelity mission profiles for bidirectional AC charging using a validated simulation model that accurately reproduces real-world field data. The mission profiles, defined as time-dependent sequences of electrical and thermal stresses experienced by power-electronic components during operation, are derived for electric vehicles in households equipped with a photovoltaic system under two operating scenarios: one with a large cost feed-in price spread, where self-consumption dominates, and one with a small price spread, enabling market-driven energy trading. Energy exchange optimization is conducted in the German Day-Ahead and combined Day-Ahead/Intraday markets. Results show that bidirectional charging substantially increases energy throughput, operating hours, and switching events of power-electronic components, with vehicle availability and annual driving distance being key factors. Sensitivity analysis further highlights that battery state-of-charge limits, auxiliary losses from cooling and communication controllers, and grid-imposed feed-in power constraints strongly affect achievable feed-in energy. The increased number of charging and switching events amplifies thermal cycling and cumulative stress on the onboard charger. For the scenarios considered, using a bidirectional electric vehicle as a mobile energy storage system can yield net savings of up to approximately 400 e per year on the household electricity bill in Germany. The developed mission profiles provide a robust foundation for component lifetime assessment and support the development of control strategies that balance profitability with component durability.