Unmanned aerial vehicles(UAVs) may play an important role in data collection and offloading in vast areas deploying wireless sensor networks, and the UAV’s action strategy has a vital influence on achieving applicabi...Unmanned aerial vehicles(UAVs) may play an important role in data collection and offloading in vast areas deploying wireless sensor networks, and the UAV’s action strategy has a vital influence on achieving applicability and computational complexity. Dynamic programming(DP) has a good application in the path planning of UAV, but there are problems in the applicability of special terrain environment and the complexity of the algorithm.Based on the analysis of DP, this paper proposes a hierarchical directional DP(DDP) algorithm based on direction determination and hierarchical model. We compare our methods with Q-learning and DP algorithm by experiments, and the results show that our method can improve the terrain applicability, meanwhile greatly reduce the computational complexity.展开更多
飞轮混合动力系统(planetary gear set based flywheel hybrid electric powertrain,PGS-FHEP)在提高车辆性能和能源利用率方面具有巨大优势。本文研究对其主要部件进行了设计和匹配,并在等效能耗最小控制策略(equivalent consumption m...飞轮混合动力系统(planetary gear set based flywheel hybrid electric powertrain,PGS-FHEP)在提高车辆性能和能源利用率方面具有巨大优势。本文研究对其主要部件进行了设计和匹配,并在等效能耗最小控制策略(equivalent consumption minimization strategy,ECMS)的基础上,引入动态规划(dynamic programming,DP)控制策略获取最优电池荷电状态(state of charge,SOC)轨迹,通过实时调整遗传算法(genetic algorithm,GA)求得的初始最优等效因子,确保实际SOC轨迹与最优轨迹相符,从而搭建了一种可实时控制的自适应等效能耗最小控制策略(adaptive equivalent consumption minimization strategy,A-ECMS),最终在中国轻型商用车行驶工况(China light-duty commercial vehicle test cycle,CLTC-C)工况下对三种控制策略进行了仿真对比。结果表明,在A-ECMS控制下,较传统ECMS相比,加装PGS-FHEP的飞轮混合动力汽车(flywheel hybrid electric vehicle,FHEV)综合能耗降低了2.51%,控制效果更接近DP控制策略;系统能量回收率可达57.72%,其中,飞轮以机械能形式回收占比23.64%。此外,能量回收过程中,飞轮的参与使电池的峰值功率显著降低。展开更多
基金supported by the National Natural Science Foundation of China(91648204 61601486)+1 种基金State Key Laboratory of High Performance Computing Project Fund(1502-02)Research Programs of National University of Defense Technology(ZDYYJCYJ140601)
文摘Unmanned aerial vehicles(UAVs) may play an important role in data collection and offloading in vast areas deploying wireless sensor networks, and the UAV’s action strategy has a vital influence on achieving applicability and computational complexity. Dynamic programming(DP) has a good application in the path planning of UAV, but there are problems in the applicability of special terrain environment and the complexity of the algorithm.Based on the analysis of DP, this paper proposes a hierarchical directional DP(DDP) algorithm based on direction determination and hierarchical model. We compare our methods with Q-learning and DP algorithm by experiments, and the results show that our method can improve the terrain applicability, meanwhile greatly reduce the computational complexity.
文摘飞轮混合动力系统(planetary gear set based flywheel hybrid electric powertrain,PGS-FHEP)在提高车辆性能和能源利用率方面具有巨大优势。本文研究对其主要部件进行了设计和匹配,并在等效能耗最小控制策略(equivalent consumption minimization strategy,ECMS)的基础上,引入动态规划(dynamic programming,DP)控制策略获取最优电池荷电状态(state of charge,SOC)轨迹,通过实时调整遗传算法(genetic algorithm,GA)求得的初始最优等效因子,确保实际SOC轨迹与最优轨迹相符,从而搭建了一种可实时控制的自适应等效能耗最小控制策略(adaptive equivalent consumption minimization strategy,A-ECMS),最终在中国轻型商用车行驶工况(China light-duty commercial vehicle test cycle,CLTC-C)工况下对三种控制策略进行了仿真对比。结果表明,在A-ECMS控制下,较传统ECMS相比,加装PGS-FHEP的飞轮混合动力汽车(flywheel hybrid electric vehicle,FHEV)综合能耗降低了2.51%,控制效果更接近DP控制策略;系统能量回收率可达57.72%,其中,飞轮以机械能形式回收占比23.64%。此外,能量回收过程中,飞轮的参与使电池的峰值功率显著降低。
