| The rapid development of automobile industry has brought convenience to people,but also caused global problems such as environmental pollution and fossil energy crisis.The development of new energy vehicles provides a feasible alternative to alleviate the excessive dependence on fossil energy and reduce the emission of harmful gases.The fuel cell hybrid vehicles(FCHV)have attracted wide attention due to its advantages of zero emission,high efficiency,long range and so on.In addition,the development of intelligent connected technology provides more space for improving the ecological driving behavior of vehicles.Eco-driving is a co-optimization problem of vehicle dynamics and powertrain control.Research on this problem can fully reveal the coupling mechanism of intelligent connected information and autonomous hybrid electric vehicles,and improve the comprehensive performance of the vehicle.In this study,a multi-objective hierarchical eco-driving control strategy for FCHV is developed to achieve real-time co-optimization of velocity planning and powertrain energy management.The research contents are as follows:Firstly,the characteristics and working modes of FCHV powertrain are analyzed,and the models of FCHV vehicle dynamics and powertrain components are established.Secondly,in the intelligent connected car-following environment,a multi-objective hierarchical eco-driving control strategy is proposed.In the upper layer,a long short-term memory network is utilized to predict the future velocity of the proceeding vehicle and an explicit dynamic traffic model is presented to predict the ego vehicle’s state of proceeding through signalized intersections.To obtain the optimal velocity,model predictive control is designed,where a multi-objective performance function is leveraged to balance safety,energy saving,and comfort.In the lower layer,an efficient multi-horizon predictive equivalent consumption minimization strategy(Mh P-ECMS)is designed,which incorporates the optimized velocity profile(short-horizon)and the predictive velocity profile in the duration of several traffic light cycles(mid-horizon)based on the aforementioned explicit dynamic traffic model.Finally,simulations in dynamic traffic scenarios and hardware-in-the-loop(HIL)experiments verify the control strategy proposed in this paper.Simulation result demonstrate that the proposed strategy can make driving smoother in vehicle-following and through signalized intersections,so as to enhance energy saving,and comfort.As integrated with Mh P-ECMS,the energy of the powertrain is reasonably distributed throughout the driving cycle,and the vehicle energy consumption is reduced.The HIL experiment further proves the effectiveness and feasibility of the hierarchical eco-driving contrtol strategy. |
