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Off-Road Fuel Cell Vehicle Analysis and Development with a Model-Based Design Approach

AVL Powertrain UK-Tom Kigezi, Bill Insup Kim, Tommi Jokela, Bo Gao
  • Technical Paper
  • 2020-01-1170
To be published on 2020-04-14 by SAE International in United States
Fuel cell and battery electric powertrains are maturing zero-emission technologies expected to complement each other in the future. At present, battery electric powertrains have emerged competitive for urban light-duty transportation while fuel cell powertrains have emerged competitive in heavy-duty commercial transportation, alongside conventional internal combustion engine propulsion. This paper assesses the benefit for fuel cell powertrains in off-road vehicles, taking into account current and target industry data for the various powertrain components. Specific emphasis is placed on three important aspects, namely driving range, vehicle weight, and vehicle cost. Additionally, owing to the increased performance demands of off-road vehicles such as high gradeability and payload capacity, the paper evaluates the merits of a two-speed transmission in comparison to a single speed transmission under drive cycle and performance testing scenarios. A detailed fuel cell model is adopted and validated with real vehicle test data, also from which a highly scalable energy management system is systematically developed. This work adds to a growing industry effort towards zero-emission electrification of off-road vehicles.
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Combined Sizing and EMS Optimization of Fuel-Cell Hybrid Powertrains for Commercial Vehicles

AVL Powertrain UK Ltd.-Tommi Jokela, Athanasios Iraklis, Bill Kim, Bo Gao
Published 2019-04-02 by SAE International in United States
During the last years, fuel-cell-based powertrains have been attracting a lot of attention from commercial vehicle manufacturers for reducing vehicle-related Greenhouse Gas (GHG) emissions. Compared to Battery-Electric Vehicles (BEV), fuel-cell-based powertrains has the strong advantage of dealing with range-anxiety, which is crucial for commercial vehicle with high duty-cycle energy requirements. Amongst the different fuel-cell types, Proton Exchange Membrane Fuel-Cells (PEMFC) have the greatest potential for utilization in automotive applications, due to their relatively high technical readiness, market availability and utilization of hydrogen (H2) fuel. In addition, Solid Oxide Fuel-Cells (SOFC) show good potential due to existing re-fueling infrastructure for light hydrocarbon fuels or heavier hydrocarbon fuels (e.g. diesel). This study focuses on the application of both PEMFCs and diesel-fueled SOFCs in Fuel-Cell Hybrid Electric Vehicle (FCHEV) architectures for commercial vehicles. Delivery vans in the 2.5 t-3.5 t weight range, coach buses and 3-axle tractor-type long-haul trucks are considered energy-driven types and highly suitable for fuel-cell systems, which offer high energy density values. Due to the high number of vehicle application types and system configurations, and…
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Predictive Energy Optimization for Connected and Automated HEVs

Jaguar Land Rover Ltd.-Alexandros Plianos, Tommi Jokela, Matthew Hancock
Published 2018-04-03 by SAE International in United States
Connected and automated vehicles (CAVs) have the potential to eliminate road vehicle collisions and other traffic incidences. Whilst the main motivation for the introduction of vehicular communication systems is to improve safety, they also provide opportunities to reduce CO2 and other harmful pollutant emissions as well as transportation energy costs. Vehicle communication link with other automobiles and Intelligent Transportation Systems (ITS), when combined with the use of on-board high definition navigation maps, enable the vehicle control systems to optimize their operation and streamline traffic flow. This paper presents the development and evaluation of proof of concept control algorithms which optimize the vehicle’s propulsive energy consumption. Consideration is also given to journey time and other drivability and autonomous driving attributes and constraints. A two-stage optimization approach is used to optimize the ego-vehicle speed trajectory and powertrain state of a Plugin Hybrid Electric Vehicle (PHEV), within a receding prediction horizon. The control algorithm is based on the Dynamic Programming (DP) optimization method. The algorithm calculates upper and lower speed constraints that have to be respected by the…
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