Modular Platform Layout Design for a Range-Extended Electric Vehicle (REEV) Chassis

Abstract

Range-Extended Electric Vehicles (REEVs) combine a complete battery-electric drivetrain with an internal combustion engine (ICE) and generator to extend usable range beyond what pure battery capacity permits. This paper presents a modular platform layout methodology for a REEV chassis and validates each stage of that methodology against independent data or a second modeling approach. Specifically, we develop and cross-validate: (1) A two-stage spreadsheet-to-WLTC-drive-cycle powertrain sizing pipeline, benchmarked against three production REEVs; (2) A coupled ANSYS/1D-analytical exhaust thermal model; (3) A mass/inertia-matrix modal analysis tool validated against ANSYS FEA; and (4) An AIS to-international standards equivalency mapping tool used to conduct a structured homologation review. Using this methodology, three candidate chassis layouts: Front-wheel drive (FWD), Rear-wheel drive (RWD), and All-wheel drive (AWD) were developed in CAD and evaluated against packaging, thermal, weight-distribution, and cost criteria. The selected RWD-biased layout achieves a pure EV range of 200 km and a total extended range of 1546 km with a 45 kWh LFP battery, a 1.5 L turbocharged fourcylinder engine, and a 250 kW traction motor, meeting AIS thermal and structural safety limits after the introduction of heat shielding around the fuel tank and battery pack. We additionally propose an offline dynamic-programming (DP) / online neural-network (NN) energy management architecture, for which literature-informed projections suggest a 7–10% fuel-economy improvement over a conventional charge-depleting/charge-sustaining (CD/CS) baseline; this component is explicitly future work.