Study On Energy Management Strategy For Hybrid Electric Vehicles Considering Battery Lifespan And Safety

Under the dual pressure of energy crisis and environmental problems,energy conservation and environmental protection have become a global consensus.New energy vehicles are widely regarded as effective solutions to alleviate environmental pollution,energy crisis and global warming.Among them,plug-in hybrid electric vehicle has the advantages of high energy economy,long mileage and rapid commercial development,and has been widely concerned as a highly competitive technology in the market.The optimization design of energy management strategy of plug-in hybrid electric vehicle is of great significance to improve the energy saving and power performance of the vehicle.However,most of the existing energy management strategies focus on how to reduce energy consumption.In fact,with the use of power batteries,the impact of battery life is becoming more and more significant,which has a great impact on the optimization process.At the same time,if the calorific value of the battery is not controlled during the operation of the vehicle,it will lead to safety problems in serious cases.Therefore,it is also very necessary to add the control of battery heat generation to the energy management strategy.Based on the problem that only energy consumption is optimized in the existing literature,this paper proposes an energy management strategy for hybrid electric vehicles considering battery life and safety.The main research contents of this paper include:(1)Firstly,the key components of PHEV power and control system are modeled mathematically.Key components include power system model,battery model,APU model and drive motor model.The main influencing factors of battery aging are analyzed,and a battery aging model which can be used in energy management strategy is established.A heat dissipation structure of battery pack including fan is proposed,and a battery thermal model including battery heat generation and battery heat dissipation system is established.(2)The battery behavior under 13 different aging conditions was studied experimentally.On this basis,a variable parameter battery model with aging consciousness was proposed to reflect the aging of the battery.The influence of battery aging on energy consumption of plug-in hybrid electric vehicle(PHEV)is quantitatively analyzed.Aiming at the influence of battery aging on PHEV energy management,the optimal control strategy of PHEV energy management is proposed.Based on particle swarm optimization algorithm,it can achieve optimal control performance in the whole battery life.The quantitative influence of battery aging on energy consumption is revealed.(3)The optimization objective function including energy consumption cost,battery aging cost and battery temperature rise change is established.The minimum principle algorithmused to solve the optimization objective function is introduced.Finally,an energy management control strategy considering both battery life and safety is proposed,including the control of starting the vehicle under high temperature conditions and the control of possible cooling component failures.(4)The energy management strategy is simulated and analyzed.The life cycle energy management strategy is simulated through two driving conditions,and the proposed energy management strategy is evaluated and analyzed.Using the minimum principle algorithm,the energy management strategy considering both battery life and safety is simulated.All-weather temperature data in Shenyang were collected,and the energy management strategy was evaluated and analyzed through simulation research in various typical scenes under the driving conditions of Shenyang real vehicle data.The results show that the cost of energy consumption can be increased by 15.19%due to the aging of the battery.However,compared with the strategy without considering battery aging,the energy consumption of battery aging can be reduced by 2.24%under certain driving conditions;The proposed energy management optimization method based on PMP algorithm can significantly improve the battery life state under high temperature operation,and control the battery temperature in case of heat dissipation system failure,improve the battery safety,and reduce the comprehensive cost compared with before optimization.The proposed energy management strategy is simulated and verified in Shenyang real vehicle driving condition.