Coordinated control of stability and anti-slip torque distribution for distributed electric vehicles under extreme operating conditions

Abstract

Under extreme operating conditions, addressing the issues of insufficient torque distribution and stability in Distributed Wheel Hub Motor-Driven Electric Vehicles (DWHDEV) caused by coupled nonlinear characteristics and safety constraints, this paper proposes an adaptive nonlinear model predictive control strategy for coordinated stability and anti-slip torque distribution. First, a 7-degree-of-freedom vehicle dynamics model is established using Matlab/Simulink. Subsequently, within the designed nonlinear model predictive controller, considering the nonlinear dynamic characteristics of slipping which is easy to occur on roads with low road adhesion coefficients, an objective function is devised that satisfies both vehicle stability and dynamic performance requirements. Based on the stability criterion of the phase plane method, a weight adaptive regulator is designed. Finally, a co-simulation model is established using Carsim and Matlab/Simulink. Simulation results show that the weight adaptive adjustment torque distribution control strategy proposed in this paper improves the handling stability by 7.6% and 10.5% over the fixed-parameter control strategy under double lane-change condition and sine steering condition, respectively, which not only meets the demand of vehicle dynamics performance, but also reduces the tire slip ratio. Therefore, the control strategy can effectively improve the stability and anti-slip capability of the vehicle under extreme working conditions.