Li-Ion Battery-Based Hybrid Diesel-Electric Railway Vehicle: In-Depth Life Cycle Cost Analysis
Olmos J., Gandiaga I., Lopez D., Larrea X., Nieva T., Aizpuru I.
IEEE Transactions on Vehicular Technology
In this study, the life cycle costs of railway projects involving hybrid diesel-electric vehicles are analysed. Specifically, the analysis focuses on the comparison of 3 lithium-ion battery technologies (NMC, LTO and LFP) and 8 energy management strategies (including rule-based and optimization-based strategies). In order to develop this analysis, a methodology that returns the life cycle cost of each proposed case is presented. The methodology includes the optimization of the diesel generator and lithium-ion battery sizing. A scenario based on a real railway line is introduced, and the obtained results are compared to a traditional diesel-electric railway vehicle to develop a techno-economical discussion. The best lithium-ion battery technologies are found to be LTO and NMC, and the most appropriated strategy a state-machine controller optimised by a genetic algorithm approach. The best case obtains a life cycle cost reduction of the 4.0% and diesel savings of the 13.7% compared to a traditional diesel-electric railway vehicle. The proposed analysis is claimed to be potentially helpful for the cost-optimal design and operation definition of powertrains for hybrid railway vehicles.