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动车组黏着控制方法研究

城市轨道交通研究 2024年第10期27卷 235-239,243页

作者：马法运张佳波苗存绪林显琦杨其林曾凡飞中车青岛四方车辆研究所有限公司青岛266031

[目的]针对动车组运行速度高、剩余加速度余量小、线路露天架设等特点,以及传统组合校正法判据提取准确性较差、转矩调节损失较多等不足,从速度采集及故障识别、判据提取、转矩调节三个方面进行分析优化,以提升动车组黏着利用。[方法]... 详细信息

[目的]针对动车组运行速度高、剩余加速度余量小、线路露天架设等特点,以及传统组合校正法判据提取准确性较差、转矩调节损失较多等不足,从速度采集及故障识别、判据提取、转矩调节三个方面进行分析优化,以提升动车组黏着利用。[方法]速度采集采用分段T法及中位值滤波方法,并对故障速度进行识别替换,以降低速度干扰或故障时对黏着控制的影响。选用加速度差值冲击率替代冲击率,并采用高通滤波器替代微分器,以减小复杂的轨面情况对黏着判据提取带来的影响。转矩调节时锁存上一触发空转/滑行时刻的转矩,并以此转矩为基准,实时计算转矩下降、上升步长;降、升转矩步长均分为10段,由大到小执行,以减小转矩损失。并以某型动车组为例进行了试验,来验证所选方法的可行性。[结果及结论]试验结果表明:在进行防空转、防滑试验的整个加、减速过程中,动轴速度偏离参考速度有限;转矩调节未有大幅度反复波动,列车冲击较小;对牵引、制动两次试验数据进行计算分析,得到牵引防空转、制动防滑行的黏着利用率均大于90%,黏着利用得到有效提升。

关键词：动车组防空转防滑行黏着控制

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一种紧凑型高效率毫米波整流天线

空间电子技术 2024年第3期21卷 56-61页

作者：岳震胥鑫李顺林先其於阳刘勇电子科技大学长三角研究院(湖州) 湖州313001 电子科技大学电子科学与工程学院成都611731

为了提高毫米波无线输能系统的接收端效率,设计了一款基于缝隙耦合馈电的紧凑型高效率毫米波整流天线,该整流天线通过划分子阵,每个子阵单独进行能量转换,采用直流合成的方式进行整合输出,具有尺寸小、剖面低、易共形等特点。天线采用... 详细信息

为了提高毫米波无线输能系统的接收端效率,设计了一款基于缝隙耦合馈电的紧凑型高效率毫米波整流天线,该整流天线通过划分子阵,每个子阵单独进行能量转换,采用直流合成的方式进行整合输出,具有尺寸小、剖面低、易共形等特点。天线采用缝隙耦合馈电,馈线和辐射贴片分别在地板的两侧,有效的减少天线电路之间的影响,同时增大了天线的有效辐射面积。后端整流电路采用单二极管并联整流拓扑,利用扇形枝节作为直通滤波器进行直流滤波。该整流天线工作频率为35GHz,天线阵列增益为23.4dBi,实测在17dBm接收功率下具有最高58.65%的整流效率,可广泛应用于毫米波无线输能系统中。

关键词：整流天线缝隙耦合毫米波高效率

Reconfigurable intelligent surfaces for smart wireless environments: channel estimation, system design and applications in 6G networks

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Science China(Information Sciences) 2021年第10期64卷 52-72页

作者： Ying-Chang LIANG Jie CHEN Ruizhe LONG Zhen-Qing HE xianqi lin Chenlu HUANG Shilin LIU Xuemin (Sherman) SHEN Marco DI RENZO Center for Intelligent Networking and Communications University of Electronic Science and Technology of China School of Electronic Science and Engineering University of Electronic Science and Technology of China Department of Electrical and Computer Engineering University of Waterloo Université Paris-Saclay CNRS CentraleSupélec Laboratoire des Signaux et Systèmes

Reconfigurable intelligent surface(RIS), one of the key enablers for the sixth-generation(6G)mobile communication networks, is considered by designers to smartly reconfigure the wireless propagation environment in a controllable and programmable manner. Specifically, an RIS consists of a large number of low-cost and passive reflective elements(REs) without radio frequency chains. The system gain of RIS wireless systems can be achieved by adjusting the phase shifts and amplitudes of the REs so that the desired signals can be added constructively at the receiver. However, an RIS typically has limited signal processing capability and cannot perform active transmitting/receiving in general, which leads to new challenges in the physical layer design of RIS wireless systems. In this paper, we provide an overview of the RIS-aided wireless systems, including the reflection principle, channel estimation, and system design. In particular,two types of emerging RIS systems are considered: RIS-aided wireless communications(RAWC) and RISbased information transmission(RBIT), where the RIS plays the role of the reflector and the transmitter,respectively. We also envision the potential applications of RIS in 6G networks.

关键词： reconfigurable intelligent surface channel estimation RIS-aided wireless communications RIS-based information transmission 6G

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基于信息交互的牵引系统控制策略研究

智慧轨道交通 2024年第1期61卷 33-37,52页

作者：张新宇张佳波林显琦周双雷曾凡飞中车青岛四方车辆研究所有限公司山东青岛266031

采用独立轮对的有轨电车可最大程度降低低地板车辆的地板高度,无需高站台设计且方便乘客上下车,发展前景十分广阔。但是独立轮对理论上不存在纵向蠕滑力,曲线导向能力下降,因此对列车牵引制动过程中的出力及控制策略提出更高要求,针对... 详细信息

采用独立轮对的有轨电车可最大程度降低低地板车辆的地板高度,无需高站台设计且方便乘客上下车,发展前景十分广阔。但是独立轮对理论上不存在纵向蠕滑力,曲线导向能力下降,因此对列车牵引制动过程中的出力及控制策略提出更高要求,针对独立轮对有轨电车的特点,本文介绍了一种牵引变流器的设计方案及控制策略,从主电路设计、工作原理、硬件结构等方面进行阐述,基于双功率模块的信息交互,从顶层给出牵引力的优化施加目标,基于分段同步调制及矢量控制策略,实现列车牵引力输出的优化控制。最后,通过现场牵引制动试验及极端恶劣线路空转滑行试验验证了所提设计方案的有效性,对独立轮对牵引系统及类似应用场合的牵引系统硬件设计及控制策略具有一定的指导意义。

关键词：有轨电车独立轮对牵引系统信息交互牵引变流器控制策略

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孤岛微网中固态变压器间环流抑制研究

中国电机工程学报 2014年第31期34卷 5563-5570页

作者：张明锐林显琦孙华同济大学电子与信息工程学院上海市嘉定区201804 上海电气集团股份有限公司中央研究院上海市闸北区200070

在未来可再生电能传输和管理微网(future renewable electric energy delivery and management,FREEDM)中固态变压器间会因输出电压偏差及输出阻抗的不匹配而产生环流,孤岛模式下尤为严重,为此,在下垂控制器中引入固态变压器(solid stat... 详细信息

在未来可再生电能传输和管理微网(future renewable electric energy delivery and management,FREEDM)中固态变压器间会因输出电压偏差及输出阻抗的不匹配而产生环流,孤岛模式下尤为严重,为此,在下垂控制器中引入固态变压器(solid state transformer,SST)间输出电压偏差反馈调节,减小输出电压相角差和幅值差;采用基于模糊控制理论的瞬时环流反馈,进行动态虚拟阻抗调节,使得SST输出阻抗按额定功率精确匹配。仿真及分析表明,电压偏差反馈调节配合动态虚拟阻抗控制可以有效地抑制SST间环流,同时提高SST输出电压的稳定性。

关键词：未来可再生电能传输和管理微网固态变压器电压偏差反馈调节动态虚拟阻抗环流抑制

A fast forward computational method for nuclear measurement using volumetric detection constraints

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Nuclear Science and Techniques 2024年第2期35卷 47-63页

作者： Qiong Zhang lin-Lv lin University of Electronic Science and Technology of China Chengdu 610000China

Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation *** the various detection tools that use nuclear sources,the detector response can reflect various types of information of the *** Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex ***,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response ***,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is ***,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo ***,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion *** environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection ***,the method is applied to a neutron porosity tool for *** various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 *** field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method.

关键词： Nuclear measurement Fast forward computation Volumetric constraints

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直接并联模块化逆变器零序环流抑制

电工技术学报 2015年第20期30卷 100-107页

作者：张明锐宋柏慧林显琦欧阳丽孙华同济大学电子与信息工程学院上海201804 青岛四方车辆研究所青岛266112 上海电气集团股份有限公司中央研究院上海200070

新型FREEDM微网中,采用逆变器直接并联技术可提高固态变压器的并网容量,但受到运算放大器零点漂移、谐波扰动以及信号延迟等因素的影响,该技术存在严重的零序环流问题。在并联逆变器间零序环流的平均模型和同步旋转坐标模型基础上,分析... 详细信息

新型FREEDM微网中,采用逆变器直接并联技术可提高固态变压器的并网容量,但受到运算放大器零点漂移、谐波扰动以及信号延迟等因素的影响,该技术存在严重的零序环流问题。在并联逆变器间零序环流的平均模型和同步旋转坐标模型基础上,分析dq0坐标轴参考信号与输出电压的关系,提出理想机模型对PWM调制波参考信号进行误差反馈调节,实现各逆变器之间互不干扰地进行零序环流抑制,采用顺序控制方案,增加了控制器的调节效率和准确度。在PSCAD/EMTDC环境下仿真结果表明,所采用控制策略对零序环流具有有效的抑制作用,同时提高了功率均分的准确度。

关键词： FREEDM微网直接并联模块化逆变器理想机模型零序环流抑制功率均分

Enhancing Safety in Autonomous Vehicle Navigation:An Optimized Path Planning Approach Leveraging Model Predictive Control

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Computers, Materials & Continua 2024年第9期80卷 3555-3572页

作者： Shih-lin lin Bo-Chen lin Graduate Institute of Vehicle Engineering National Changhua University of EducationChanghua50007TaiwanChina

This paper explores the application of Model Predictive Control(MPC)to enhance safety and efficiency in autonomous vehicle(AV)navigation through optimized path *** evolution of AV technology has progressed rapidly,moving from basic driver-assistance systems(Level 1)to fully autonomous capabilities(Level 5).Central to this advancement are two key functionalities:Lane-Change Maneuvers(LCM)and Adaptive Cruise Control(ACC).In this study,a detailed simulation environment is created to replicate the road network between Nantun andWuri on National Freeway No.1 in *** MPC controller is deployed to optimize vehicle trajectories,ensuring safe and efficient *** onboard sensors,including vehicle cameras and millimeterwave radar,are used to detect and respond to dynamic changes in the surrounding environment,enabling real-time decision-making for LCM and *** simulation resultshighlight the superiority of the MPC-based approach in maintaining safe distances,executing controlled lane changes,and optimizing fuel ***,the MPC controller effectively manages collision avoidance,reduces travel time,and contributes to smoother traffic flow compared to traditional path planning *** findings underscore the potential of MPC to enhance the reliability and safety of autonomous driving in complex traffic *** research will focus on validating these results through real-world testing,addressing computational challenges for real-time implementation,and exploring the adaptability of MPC under various environmental *** study provides a significant step towards achieving safer and more efficient autonomous vehicle navigation,paving the way for broader adoption of MPC in AV systems.

关键词： Autonomous driving model predictive control(MPC) lane change maneuver(LCM) adaptive cruise control(ACC)

The Existence of a Meridional Curve in Closed Incompressible Surfaces in Fully Alternating link Complements

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 73-80页

作者： Wei lin School of Mathematical Sciences Dalian University of TechnologyDalian 116024LiaoningChina

Menasco showed that a closed incompressible surface in the complement of a non-split prime alternating link in S^(3) contains a circle isotopic in the link complement to a meridian of the *** on this result,he was able to argue the hyperbolicity of non-split prime alternating links in *** et *** that if F■S×I\L is an essential torus,then F contains a circle which is isotopic in S×I\L to a meridian of *** author generalizes his result as follows:Let S be a closed orientable surface,L be a fully alternating link in S×I\If F ■ S×I\L is a closed essential surface,then F contains a circle which is isotopic in S×I\L to a meridian of L.

关键词： Fully alternating Incompressible surfaces Meridionally incompressible