| In the context of energy crisis and environmental pollution,hybrid electric vehicles are developing rapidly as new energy vehicles with potential in the automotive industry at the current technological level.In this paper,a certain parallel hybrid electric passenger vehicle is selected as the research platform,and the research is carried out on the energy optimization management of the hybrid electric vehicle and the active damping of the powertrain system.The specific research work is as follows:First,the construction of the hybrid electric vehicle simulation model using forward simulation is studied,and the vehicle simulation model based on SIMULINK is built to realize the accurate simulation of the power and economic performance of the parallel hybrid electric vehicle.The power source torque distribution strategies corresponding to different equivalent factor values are analyzed,and the effects of the equivalent factor on the battery SOC balance and fuel consumption throughout the working conditions are explained.Then,the hybrid energy management strategy is studied through the combination of operating condition prediction,dynamic programming and model predictive control.The working condition prediction model is designed based on the exponential function,and the vehicle speed information in the future limited time domain is predicted.By applying dynamic programming to the framework of model predictive control,an energy management strategy for HEVs based on DP-MPC is proposed.The DP-MPC energy management strategy takes the minimum fuel consumption in the predicted time domain as the objective function,and obtains the torque distribution strategy of the HEV by solving the minimum value of the objective function in the future limited time domain.By comparing with the global optimal solution obtained by the dynamic programming algorithm,it is verified that the energy management strategy based on DP-MPC still has good optimization performance in terms of fuel economy.Finally,the active damping of parallel hybrid powertrain system is studied.The powertrain system is equivalent to a two-mass spring damping system,and a SIMULINK simulation model is built,a state observer is designed,and the online observation of the torsion angle is realized.The linear quadratic regulator achieves the purpose of suppressing the torsional vibration of the powertrain system.The active damping performance of the linear quadratic regulator is studied by changing the parameters of the reference model.The results verify that even if the parameters of the controller model have significant errors,the active damping controller proposed in this paper still has a good effect of suppressing the overshoot of the torsion angle and maintains a good vibration reduction effect. |
