Impact of trailer electrification on tow vehicle dynamic performance and energy economy

Vehicle-trailer systems are widely used in freight transport, yet the conventional passive trailer significantly diminishes the dynamic performance and energy economy of the tow vehicle. This study presents a comprehensive, model-based assessment of how trailer electrification influences the dynamic performance and energy economy of the tow vehicle. Longitudinal dynamics models are developed for a single-vehicle baseline and two vehicle-trailer configurations with passive and electric trailers. An optimal driving force distribution strategy based on adhesion utilization is proposed and applied consistently across the considered cases. For the electric-trailer system, an instantaneous power-split optimization method is used to provide a consistent benchmark across configurations for energy-economy evaluation in terms of equivalent fuel consumption. Simulation results demonstrate that the Vehicle-Electric-Trailer system effectively mitigates the severe performance degradations of the passive configuration. It reduces the increase in 0–100 km/h acceleration time from 202.9% to 62.9%, significantly improving tire-road adhesion utilization, and cuts the equivalent fuel consumption increase from 107.3% to 53.9% and 149.9% to 109.6% under the China Highway Driving Cycle and Worldwide Harmonized Light Vehicles Test Cycle. These findings validate the electric trailer as an active drivetrain component that can enhance the dynamic economic performance of the vehicle-trailer system, providing a practical solution for vehicle-trailer operations.