This study presents a methodology to enhance energy management systems(EMS)in hybrid electric vehicles(HEVs)to reduce fuel consumption and greenhouse gas emissions.A novel surrogate-assisted optimization framework is ...This study presents a methodology to enhance energy management systems(EMS)in hybrid electric vehicles(HEVs)to reduce fuel consumption and greenhouse gas emissions.A novel surrogate-assisted optimization framework is employed,incorporating key performance metrics such as fuel efficiency and emissions to develop data-driven surrogate models of the EMS.These models are optimized using various algorithms targeting parameters such as engine idle speed,thermostat temperature fraction,regeneration load factor,and battery stateof-charge thresholds.Correlation analysis highlights the significant impact of the lower state-of-charge threshold and thermostat temperature fraction on fuel efficiency and emissions.Among the optimization methods,the combination of a backpropagation neural network(BPNN)and a multi-objective genetic algorithm(MOGA)proves most effective,achieving fuel consumption reductions of 5.26%and 5.01%in charge-sustaining and charge-depletion modes,respectively.Additionally,the BPNN-based MOGA demonstrates notable improvements in emission reduction.These findings suggest that optimizing rule-based EMS parameters without altering underlying management rules can significantly enhance performance under diverse and unanticipated driving conditions.展开更多
This paper studied a supervisory control system for a hybrid off-highway electric vehicle under the chargesustaining(CS)condition.A new predictive double Q-learning with backup models(PDQL)scheme is proposed to optimi...This paper studied a supervisory control system for a hybrid off-highway electric vehicle under the chargesustaining(CS)condition.A new predictive double Q-learning with backup models(PDQL)scheme is proposed to optimize the engine fuel in real-world driving and improve energy efficiency with a faster and more robust learning process.Unlike the existing“model-free”methods,which solely follow on-policy and off-policy to update knowledge bases(Q-tables),the PDQL is developed with the capability to merge both on-policy and off-policy learning by introducing a backup model(Q-table).Experimental evaluations are conducted based on software-in-the-loop(SiL)and hardware-in-the-loop(HiL)test platforms based on real-time modelling of the studied vehicle.Compared to the standard double Q-learning(SDQL),the PDQL only needs half of the learning iterations to achieve better energy efficiency than the SDQL at the end learning process.In the SiL under 35 rounds of learning,the results show that the PDQL can improve the vehicle energy efficiency by 1.75%higher than SDQL.By implementing the PDQL in HiL under four predefined real-world conditions,the PDQL can robustly save more than 5.03%energy than the SDQL scheme.展开更多
文摘This study presents a methodology to enhance energy management systems(EMS)in hybrid electric vehicles(HEVs)to reduce fuel consumption and greenhouse gas emissions.A novel surrogate-assisted optimization framework is employed,incorporating key performance metrics such as fuel efficiency and emissions to develop data-driven surrogate models of the EMS.These models are optimized using various algorithms targeting parameters such as engine idle speed,thermostat temperature fraction,regeneration load factor,and battery stateof-charge thresholds.Correlation analysis highlights the significant impact of the lower state-of-charge threshold and thermostat temperature fraction on fuel efficiency and emissions.Among the optimization methods,the combination of a backpropagation neural network(BPNN)and a multi-objective genetic algorithm(MOGA)proves most effective,achieving fuel consumption reductions of 5.26%and 5.01%in charge-sustaining and charge-depletion modes,respectively.Additionally,the BPNN-based MOGA demonstrates notable improvements in emission reduction.These findings suggest that optimizing rule-based EMS parameters without altering underlying management rules can significantly enhance performance under diverse and unanticipated driving conditions.
基金Project(KF2029)supported by the State Key Laboratory of Automotive Safety and Energy(Tsinghua University),ChinaProject(102253)supported partially by the Innovate UK。
文摘This paper studied a supervisory control system for a hybrid off-highway electric vehicle under the chargesustaining(CS)condition.A new predictive double Q-learning with backup models(PDQL)scheme is proposed to optimize the engine fuel in real-world driving and improve energy efficiency with a faster and more robust learning process.Unlike the existing“model-free”methods,which solely follow on-policy and off-policy to update knowledge bases(Q-tables),the PDQL is developed with the capability to merge both on-policy and off-policy learning by introducing a backup model(Q-table).Experimental evaluations are conducted based on software-in-the-loop(SiL)and hardware-in-the-loop(HiL)test platforms based on real-time modelling of the studied vehicle.Compared to the standard double Q-learning(SDQL),the PDQL only needs half of the learning iterations to achieve better energy efficiency than the SDQL at the end learning process.In the SiL under 35 rounds of learning,the results show that the PDQL can improve the vehicle energy efficiency by 1.75%higher than SDQL.By implementing the PDQL in HiL under four predefined real-world conditions,the PDQL can robustly save more than 5.03%energy than the SDQL scheme.