The Influence of Road Adhesion Coefficient on Energy Consumption and Dynamics of Battery Electric Vehicles

Abstract

Currently, in economically developed countries, electric vehicles are considered as a solution to the problematic issue of reducing greenhouse gas emissions from road vehicles. The level of energy consumption is a critical factor in determining the overall performance of an electric vehicle. The article analyzes the influence of tire adhesion coefficient on the energy consumption of a battery electric vehicle when operating in typical standard driving cycles. In order to estimate the energy consumption during driving with different tire adhesion coefficients an electric vehicle longitudinal dynamic model is used, which allows taking into account various driving modes (Eco, Comfort, Sport) and sliding of the drive wheels in contact with the road surface. The proposed model, based on submodels of such main components of an electric vehicle as an electric motor and a traction battery, includes tire and vehicle body dynamics submodels, as well as a human-driver submodel with PID controller in the control circuit to track given trajectories. A series of experiments with the VinFast Vf e34 passenger electric vehicle on a dynamometer test bench were carried out to determine the electric motor’s performance characteristics at various operating modes and identify many other input parameters for simulation and verifying the mathematical model accuracy. The simulation results of the distance traveled by an electric vehicle on a single charge are compared withthe manufacturer's experimental data during operating the test vehicle in the standard European driving cycle. Simulation scenarios with different accelerating modes are proposed to analyze the influence of the adhesion coefficient on the EV’s dynamic characteristics and the level of energy consumption. The simulation results on the determination of the energy consumed by an electric vehicle when moving in various driving cycles with road adhesion coefficients are presented in the activity. The given results show the significant impact of the adhesion coefficient on electric vehicle energy consumption in various standard driving cycles, especially on low-grip roads.