Abstract
This paper investigates opportunities to reduce hydrogen consumption in a hybrid heavy-duty vehicle powered by an electric machine (EM) and multiple fuel cells (FC). Rather than relying solely on high-level energy management algorithms, the study first exploits the inherent energy-saving potential of the powertrain. Two key opportunities are examined: optimal gear shifting to improve EM operating efficiency and optimal power distribution among FCs. A longitudinal vehicle model is used to relate wheel power demand to EM torque and speed, enabling the evaluation of FC power requirements. An optimization routine determines the optimal gear for each EM operating point, while an optimal load allocation strategy distributes power among FCs considering their performance characteristics and remaining useful life. Results for the Paris–Munich ESCALATE drive cycle show that optimal gear selection reduces EM power demand by up to 50 kW, and optimal FC power distribution lowers hydrogen consumption by up to 3.1%.