蜂窝车联网(cellular vehicle to everything,C-V2X)是智能交通系统的关键技术之一,车辆通过与周围的信息实体实时交换信息以实现保障城市交通安全、提高城市交通效率等目的,实现V2X通信的基本需求。在NR-V2X定义的场景中,它还将支持自...蜂窝车联网(cellular vehicle to everything,C-V2X)是智能交通系统的关键技术之一,车辆通过与周围的信息实体实时交换信息以实现保障城市交通安全、提高城市交通效率等目的,实现V2X通信的基本需求。在NR-V2X定义的场景中,它还将支持自动驾驶、远程驾驶、车辆编队、扩展传感四大类先进V2X服务。通过OPNET搭建5G-V2X系统级仿真平台,针对基于PC5接口和Uu接口的车联网通信两大通信模式对5G蜂窝车联网的系统性能进行分析研究,给出相应的性能分析和评估结果,并提出改进建议,对5G蜂窝车联网的研究方向和实际系统部署都具有重要的指导作用。展开更多
针对新能源并网的主动支撑应用需求问题,选取三相全桥AC-DC变换器加双有源桥(dual active bridge,DAB)变换器的两级式结构作为研究对象。在器件寄生电容的影响下,DAB变换器会面临软开关难以实现的问题;且在宽电压范围应用场合下,传统的...针对新能源并网的主动支撑应用需求问题,选取三相全桥AC-DC变换器加双有源桥(dual active bridge,DAB)变换器的两级式结构作为研究对象。在器件寄生电容的影响下,DAB变换器会面临软开关难以实现的问题;且在宽电压范围应用场合下,传统的拓展移相(extend phase shift,EPS)控制在远离单位电压增益点时会带来较大无功环流问题。因此,提出一种拓扑结构及其调制方法,通过添加激磁电感来注入额外的激磁电流,从而保证DAB变换器的全负载范围软开关实现,同时通过对传统EPS控制进行改进,保证宽电压范围下的高效率传能。最后搭建一个20 kW全SiC器件的实验样机,对装置进行稳态测试及软开关性能测试,验证了所提方法的有效性。展开更多
The number of accidents in the campus of Suranaree University of Technology(SUT)has increased due to increasing number of personal vehicles.In this paper,we focus on the development of public transportation system usi...The number of accidents in the campus of Suranaree University of Technology(SUT)has increased due to increasing number of personal vehicles.In this paper,we focus on the development of public transportation system using Intelligent Transportation System(ITS)along with the limitation of personal vehicles using sharing economy model.The SUT Smart Transit is utilized as a major public transportation system,while MoreSai@SUT(electric motorcycle services)is a minor public transportation system in this work.They are called Multi-Mode Transportation system as a combination.Moreover,a Vehicle toNetwork(V2N)is used for developing theMulti-Mode Transportation system in the campus.Due to equipping vehicles with On Board Unit(OBU)and 4G LTE modules,the real time speed and locations are transmitted to the cloud.The data is then applied in the proposed mathematical model for the estimation of Estimated Time of Arrival(ETA).In terms of vehicle classifications and counts,we deployed CCTV cameras,and the recorded videos are analyzed by using You Only Look Once(YOLO)algorithm.The simulation and measurement results of SUT Smart Transit and MoreSai@SUT before the covid-19 pandemic are discussed.Contrary to the existing researches,the proposed system is implemented in the real environment.The final results unveil the attractiveness and satisfaction of users.Also,due to the proposed system,the CO_(2) gas gets reduced when Multi-Mode Transportation is implemented practically in the campus.展开更多
文摘蜂窝车联网(cellular vehicle to everything,C-V2X)是智能交通系统的关键技术之一,车辆通过与周围的信息实体实时交换信息以实现保障城市交通安全、提高城市交通效率等目的,实现V2X通信的基本需求。在NR-V2X定义的场景中,它还将支持自动驾驶、远程驾驶、车辆编队、扩展传感四大类先进V2X服务。通过OPNET搭建5G-V2X系统级仿真平台,针对基于PC5接口和Uu接口的车联网通信两大通信模式对5G蜂窝车联网的系统性能进行分析研究,给出相应的性能分析和评估结果,并提出改进建议,对5G蜂窝车联网的研究方向和实际系统部署都具有重要的指导作用。
基金This work was supported by Suranaree University of Technology(SUT).The authors would also like to thank SUT Smart Transit and Thai AI for supporting the experimental and datasets.
文摘The number of accidents in the campus of Suranaree University of Technology(SUT)has increased due to increasing number of personal vehicles.In this paper,we focus on the development of public transportation system using Intelligent Transportation System(ITS)along with the limitation of personal vehicles using sharing economy model.The SUT Smart Transit is utilized as a major public transportation system,while MoreSai@SUT(electric motorcycle services)is a minor public transportation system in this work.They are called Multi-Mode Transportation system as a combination.Moreover,a Vehicle toNetwork(V2N)is used for developing theMulti-Mode Transportation system in the campus.Due to equipping vehicles with On Board Unit(OBU)and 4G LTE modules,the real time speed and locations are transmitted to the cloud.The data is then applied in the proposed mathematical model for the estimation of Estimated Time of Arrival(ETA).In terms of vehicle classifications and counts,we deployed CCTV cameras,and the recorded videos are analyzed by using You Only Look Once(YOLO)algorithm.The simulation and measurement results of SUT Smart Transit and MoreSai@SUT before the covid-19 pandemic are discussed.Contrary to the existing researches,the proposed system is implemented in the real environment.The final results unveil the attractiveness and satisfaction of users.Also,due to the proposed system,the CO_(2) gas gets reduced when Multi-Mode Transportation is implemented practically in the campus.
