Abstract
This paper presents design of a vehicle stability control system for a micro electric vehicle with four in-wheel motors by driving/braking torque control considering both vehicle handling and stability and energy consumption efficiency of in-wheel motors. To obtain a vehicle dynamical model for design of the vehicle stability control system, the subspace system identification method is applied using the input/output signals obtained from simulations of the full vehicle model. The full vehicle model constructed by a simulation software based on the Modelica modeling language have been provided by the benchmark problem No.3 of the Society of Automotive Engineers of Japan and the Society of Instrument and Control Engineers. After analyzing frequency responses for the identified vehicle model, an H-infmity controller is designed to meet the requirement in terms of vehicle handling and stability and energy consumption efficiency of in-wheel motors. By carrying out simulations under the crossing side wind test and the double lane change test for the vehicle model, it is demonstrated that the proposed control system satisfies the performance requirements.