Time-Domain Modeling and Simulation of a Fuel Cell Hybrid Truck Powertrain Operating in Port Logistics

The implementation of cleaner technologies in the propulsion of heavy-duty vehicles can contribute reducing the environmental impact of the port-logistic industry. This paper provides a time-domain model of the power unit in a hybrid fuel cell/battery tractor used in port logistics equipped with an electric motor for propulsion. The proposed time-domain model is assessed with numerical and experimental analyses. Two energy management strategies that rule the powertrain energy flows are tested and implemented in an energy-based numerical approach and within the proposed time-domain simulator framework, and the results are compared with those obtained experimentally at the test bench. This allows evaluating not only the energy variables but also the time behavior of several electric parameters that are of particular concern in the real-world development of the truck. The results evidence a substantial agreement between the two numerical methods and the actual experimental data, with percentage deviations below 4% (mean) and 6.5% (root mean square). Moreover, the analysis shows that the electrical components well behave under both the considered energy management strategies, and that the adopted control systems are suitable to ensure the correct operation of the vehicle's powertrain undergoing different typical duty cycles.