A Plug-In Hybrid Electric Vehicle Concept with Fuel Cell Range Extender for Urban Delivery Transport – Vehicle Application 2023-01-0491

The electrification of vehicle fleets for urban delivery transport is becoming increasingly important due to ever stricter legal requirements and the high public pressure on companies. In this paper, a converted 3.5 t light-duty vehicle with a maximum gross weight of 7.5 t is presented. The vehicle has a serial hybrid electric powertrain with a maximum electric traction power of 150 kW and a 60 kW fuel cell range extender, and uses a 46 kWh battery with 400 V mean voltage level, resulting in a full electric range of 120 km. The electric drive is realized with an induction motor and a lithium-manganese-iron-phosphate (LMFP)-battery as well as a 2-speed gearbox. The fuel cell system has a fuel tank with 100 l volume and 700 bar pressure level, resulting in a total mass of around 4.2 kg of hydrogen. This enables an overall vehicle range of 400 km. For the fuel cell system, a newly developed concept with a rated power of 1.0 W/cm² and an electrically assisted turbocharger is introduced [1]. To reach optimal results for the electric and the hydrogen energy consumption, the vehicle applies an operating strategy based on the Equivalent Consumption Minimization Strategy (ECMS). This operating strategy uses a global optimization algorithm in combination with the local optimized hydrogen consumption provided by the ECMS, to calculate the minimum possible energy consumption for the vehicle. This is achieved by using a reference drive cycle in charge sustaining mode. The vehicle is afterwards simulated with two additional drive cycles. The first drive cycle is a low load urban driving scenario with an overall range 7.85 km, the second a medium load urban delivery scenario simulating a vehicle day tour of 150 km and an overall duration of around 6 h and 45 min. Both drive cycles are simulated in charge-depleting mode. Finally, the operation of the different powertrain components as well as the electric energy and hydrogen consumption is presented.