The various uncertainties of Mars environment have great impact on the process of vehicles entering the atmosphere.To improve the robustness of control system against the model errors and to reduce the computational b...The various uncertainties of Mars environment have great impact on the process of vehicles entering the atmosphere.To improve the robustness of control system against the model errors and to reduce the computational burden, an optimal feedback based tracking control law is developed. The control scheme presented in this paper determines the amplitude and the reversals of bank angle respectively in the longitudinal and lateral flight plane. At each control cycle, the amplitude of the bank angle is obtained by an optimal feedback controller to minimize tracking errors. The control gains are tuned according to the closed-loop error dynamics by using optimization methods. The bank reversals are executed if the crossrange exceeds a predetermined corridor which is designed by setting a boundary function. The accuracy and robustness of the proposed closed-loop optimal feedback based control law in tracking the reference trajectory is verified via500 deviation simulations, in which modeling errors and external disturbances are considered.展开更多
From the viewpoint of continuous systems, optimal control problem is proposed for a class of controlled Hybrid dynamical systems. Then a mathematical method- HDS minimum principle is put forward, which can solve the a...From the viewpoint of continuous systems, optimal control problem is proposed for a class of controlled Hybrid dynamical systems. Then a mathematical method- HDS minimum principle is put forward, which can solve the above problem. The HDS minimum principle is proved by means of Ekeland＇ s variational principle.展开更多
The utilization of traffic information received from intelligent vehicle highway systems(IVHS) to plan velocity and split output power for multi-source vehicles is currently a research hotspot. However, it is an open ...The utilization of traffic information received from intelligent vehicle highway systems(IVHS) to plan velocity and split output power for multi-source vehicles is currently a research hotspot. However, it is an open issue to plan vehicle velocity and distribute output power between different supply units simultaneously due to the strongly coupling characteristic of the velocity planning and the power distribution. To address this issue, a flexible predictive power-split control strategy based on IVHS is proposed for electric vehicles(EVs) equipped with battery-supercapacitor system(BSS). Unlike hierarchical strategies to plan vehicle velocity and distribute output power separately, a monolayer model predictive control(MPC) method is employed to optimize them online at the same time. Firstly, a flexible velocity planning strategy is designed based on the signal phase and time(SPAT) information received from IVHS and then the Pontryagin’s minimum principle(PMP) is adopted to formulate the optimal control problem of the BSS. Then, the flexible velocity planning strategy and the optimal control problem of BSS are embedded into an MPC framework, which is online solved using the shooting method in a fashion of receding horizon. Simulation results verify that the proposed strategy achieves a superior performance compared with the hierarchical strategy in terms of transportation efficiency, battery capacity loss, energy consumption and computation time.展开更多
根据柴油发动机台架试验结果,分析排气背压对发动机性能的影响,在设计插电式柴电混合动力汽车(plug-in hybrid electric vehicle,PHEV)控制策略时考虑排气背压对油耗与排放的影响因素.以排气背压和蓄电池荷电状态为状态变量,利用庞特里...根据柴油发动机台架试验结果,分析排气背压对发动机性能的影响,在设计插电式柴电混合动力汽车(plug-in hybrid electric vehicle,PHEV)控制策略时考虑排气背压对油耗与排放的影响因素.以排气背压和蓄电池荷电状态为状态变量,利用庞特里亚金极小值原理,求解以插电式混合动力汽车油耗与颗粒物排放量的多目标泛函,从而得到整车油耗与排放综合最优控制策略.在MATLAB/Simulink仿真平台下建立了包含柴油颗粒过滤器(diesel particle filter,DPF)压力损失和捕集效率模型的整车动力学模型,对上述所得最优控制策略进行验证,并与二阶段(charge-depleting and charge-sustaining,CD–CS)控制策略和无排气背压状态最优控制策略进行对比.仿真结果表明,本文建立的最优控制策略相对于其它两种控制策略均能明显降低排气背压升高对发动机性能的影响,有效地改善了整车燃油经济性和排放性.最后通过台架试验对所提出的最优控制策略的有效性进行验证,结果表明,采用该控制策略优化后的等效燃油消耗量与颗粒物(particulate matter,PM)排放量分别降低了9.68%和32%.展开更多
研究一种在空间3-D中求解弹道修正的最优控制问题的方法。根据Pontryagin极小值原理,将弹道修问题被转换成两点边值问题(Two-Point Boundary Value Problem,TPBVP),利用给定的边界条件,可将TPBVP可转换成针对主导向量初始值的参数优化问...研究一种在空间3-D中求解弹道修正的最优控制问题的方法。根据Pontryagin极小值原理,将弹道修问题被转换成两点边值问题(Two-Point Boundary Value Problem,TPBVP),利用给定的边界条件,可将TPBVP可转换成针对主导向量初始值的参数优化问题,并采用共轭算法求解主导向量初值。采用该控制方法进行了仿真实验以证明其可行性及准确性,仿真实验数据表明:所提出的算法鲁棒性强、精度高,可以满足战术需要。展开更多
基金supported by the National Natural Science Foundation of China(11372345)
文摘The various uncertainties of Mars environment have great impact on the process of vehicles entering the atmosphere.To improve the robustness of control system against the model errors and to reduce the computational burden, an optimal feedback based tracking control law is developed. The control scheme presented in this paper determines the amplitude and the reversals of bank angle respectively in the longitudinal and lateral flight plane. At each control cycle, the amplitude of the bank angle is obtained by an optimal feedback controller to minimize tracking errors. The control gains are tuned according to the closed-loop error dynamics by using optimization methods. The bank reversals are executed if the crossrange exceeds a predetermined corridor which is designed by setting a boundary function. The accuracy and robustness of the proposed closed-loop optimal feedback based control law in tracking the reference trajectory is verified via500 deviation simulations, in which modeling errors and external disturbances are considered.
文摘From the viewpoint of continuous systems, optimal control problem is proposed for a class of controlled Hybrid dynamical systems. Then a mathematical method- HDS minimum principle is put forward, which can solve the above problem. The HDS minimum principle is proved by means of Ekeland＇ s variational principle.
基金supported by the National Natural Science Foundation of China (62173303)the Fundamental Research for the Zhejiang P rovincial Universities (RF-C2020003)。
文摘The utilization of traffic information received from intelligent vehicle highway systems(IVHS) to plan velocity and split output power for multi-source vehicles is currently a research hotspot. However, it is an open issue to plan vehicle velocity and distribute output power between different supply units simultaneously due to the strongly coupling characteristic of the velocity planning and the power distribution. To address this issue, a flexible predictive power-split control strategy based on IVHS is proposed for electric vehicles(EVs) equipped with battery-supercapacitor system(BSS). Unlike hierarchical strategies to plan vehicle velocity and distribute output power separately, a monolayer model predictive control(MPC) method is employed to optimize them online at the same time. Firstly, a flexible velocity planning strategy is designed based on the signal phase and time(SPAT) information received from IVHS and then the Pontryagin’s minimum principle(PMP) is adopted to formulate the optimal control problem of the BSS. Then, the flexible velocity planning strategy and the optimal control problem of BSS are embedded into an MPC framework, which is online solved using the shooting method in a fashion of receding horizon. Simulation results verify that the proposed strategy achieves a superior performance compared with the hierarchical strategy in terms of transportation efficiency, battery capacity loss, energy consumption and computation time.
文摘根据柴油发动机台架试验结果,分析排气背压对发动机性能的影响,在设计插电式柴电混合动力汽车(plug-in hybrid electric vehicle,PHEV)控制策略时考虑排气背压对油耗与排放的影响因素.以排气背压和蓄电池荷电状态为状态变量,利用庞特里亚金极小值原理,求解以插电式混合动力汽车油耗与颗粒物排放量的多目标泛函,从而得到整车油耗与排放综合最优控制策略.在MATLAB/Simulink仿真平台下建立了包含柴油颗粒过滤器(diesel particle filter,DPF)压力损失和捕集效率模型的整车动力学模型,对上述所得最优控制策略进行验证,并与二阶段(charge-depleting and charge-sustaining,CD–CS)控制策略和无排气背压状态最优控制策略进行对比.仿真结果表明,本文建立的最优控制策略相对于其它两种控制策略均能明显降低排气背压升高对发动机性能的影响,有效地改善了整车燃油经济性和排放性.最后通过台架试验对所提出的最优控制策略的有效性进行验证,结果表明,采用该控制策略优化后的等效燃油消耗量与颗粒物(particulate matter,PM)排放量分别降低了9.68%和32%.
文摘研究一种在空间3-D中求解弹道修正的最优控制问题的方法。根据Pontryagin极小值原理,将弹道修问题被转换成两点边值问题(Two-Point Boundary Value Problem,TPBVP),利用给定的边界条件,可将TPBVP可转换成针对主导向量初始值的参数优化问题,并采用共轭算法求解主导向量初值。采用该控制方法进行了仿真实验以证明其可行性及准确性,仿真实验数据表明:所提出的算法鲁棒性强、精度高,可以满足战术需要。
