Global Optimization of Hysteresis Energy Management Strategies for Fuel Cell Hybrid Electric Vehicles

Fuel Cell Hybrid Electric Vehicles (FCHEVs) represent a new generation of environmentally friendly transportation technologies and have garnered significant global attention due to their potential to reduce emissions and reliance on fossil fuels. One of the critical challenges in FCHEV development lies in the design and optimization of the energy management strategy (EMS), which plays a pivotal role in determining how energy is distributed among the various power sources to maximize vehicle performance, minimize fuel consumption, and prolong system longevity, all while adhering to operational constraints. This study focuses on evaluating and optimizing EMS configurations within two distinct powertrain architectures. The first configuration, referred to as FCB, consists of a Fuel Cell System (FCS) coupled with a high-capacity battery. The second, more advanced configuration—termed FCBUC—integrates an ultracapacitor alongside the FCS and battery to enhance responsiveness and energy efficiency. Both systems were modeled and simulated using a hysteresis-based EMS, which governs the switching logic between power sources based on state-of-charge (SOC) thresholds and power demand fluctuations. To further enhance performance, a global optimization technique was employed to fine-tune key control parameters, ensuring that the system operated near optimal efficiency throughout a realistic urban driving cycle, specifically modeled after conditions in Vietnam. The results demonstrate that the proposed EMSs significantly improve system behavior by efficiently managing power flow and reducing hydrogen fuel consumption. Notably, the FCBUC configuration exhibited superior energy distribution capability and fuel economy by 11.7% reduction in hydrogen consumption and improved efficiency (59.07% avg. for FCBUC) compared to the FCB model. This study highlights the importance of advanced EMS design and powertrain configuration in realizing the full potential of FCHEV technologies in real-world urban environments.