Integrated Experimental and Physics-Based Assessment of Energy and Drivetrain Performance in a Small Utility Electric Vehicle

Energy performance in small utility electric vehicles (SUEVs) emerges from coupled interactions among route topology, tire condition, transported load, drivetrain operating point, and battery state. However, integrated experimental analyses of these factors remain scarce, particularly for commercial platforms with limited manufacturer information. This study presents an experimental and physics-based framework for system-level characterization of a commercial SUEV under realistic operating conditions. An onboard acquisition system records DC bus and induction motor voltages and currents, complemented by GNSS measurements. Physics-based observers derived from the motor model reconstruct rotor flux, electromagnetic torque, rotor speed, and converted mechanical power, enabling energy flow analysis and effective transmission ratio identification with reduced instrumentation. Tests were conducted on flat, uphill, and downhill campus routes under four tire pressure levels and two payload conditions. Under baseline conditions, normalized DC energy consumption ranged from 1.13 kWh/100 km on the downhill route to 19.86 kWh/100 km on the uphill route, demonstrating the dominant influence of terrain. Severe tire underinflation increased consumption by 26.0%, 30% and 52.2% on the flat, uphill and downhill routes, respectively. Beyond the specific numerical results, the proposed framework integrates electrical measurements, physics-based modeling, virtual sensing, and energy performance indicators into a unified methodology for characterizing commercial SUEVs under real operating conditions, even when proprietary drivetrain information is unavailable.