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A Parallel Control Strategy for the Cascaded Multi-Level Inverters in the Distributed Generation System 36

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A Parallel Control Strategy for the Cascaded Multi-Level Inv...

Simulations of Tapered Channel in Multilayer Graphene as Reverse Osmosis Membrane for Desalination

第36届中国控制会议

作者： Daoji Qiao tianzhen wang Tianhao Tang M.E.H.Benbouzid Shanghai Maritime University

ISBN: (纸本)9781538629185

In the distributed generation systems,three-phase inverters are the basement because they are used as power electronics interface between the generators and the *** multi-level H-bridge inverters are widely used for industrial application due to the simple topology and good power ***,unbalanced power source problem will easily happen in such an *** this paper,a parallel control strategy for three-phase cascaded multi-level H-bridge inverters is *** voltage and current inner control loops are introduced to deal with unbalanced power source *** droop method with the virtual impedance loops is introduced in order to share power between parallel ***,a secondary control method is added to remove the frequency and amplitude deviation produced by the droop *** performance and robustness under Islanded operation mode are validated by the simulation results.

关键词： Cascaded Multi-Level H-bridge Inverter Unbalance Power Source Droop Control Secondary Control Islanded Mode

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Journal of Wuhan University of Technology(Materials Science) 2022年第3期37卷 314-323页

作者： wang tianzhen CHEN Bo SHAO Xingyu ZHENG Huai HU Xuejiao JIANG Haifeng Key Laboratory of Hydraulic Machinery Transients(Wuhan University) Ministry of EducationSchool of Power and Mechanical EngineeringWuhan UniversityWuhan 430072China Research Institute of Tsinghua University in Shenzhen Shenzhen 518071China

Pressure-driven reverse osmosis membrane has important application in seawater *** by the structure of aquaporin,we established and studied the mechanism of the structure of multilayer graphene with tapered channels as reverse *** water flux of multilayer graphene with tapered channels was about 20%higher than that of parallel graphene *** flow resistance model was established,and the relationship between flow resistance and opening angles was *** relationship between flow resistance and outlet size was also *** means of molecular dynamics simulation,slip coefficients of multilayer graphene with tapered channel were obtained and verified by the contact angle of *** show that the permeability of graphene with tapered channel is about three orders of magnitude higher than that of commercial reverse osmosis membrane and the desalination rate is 100%.Temperature difference between the two sides of the tapered channel will promote the water flux positively.

关键词： multilayer graphene molecular dynamics tapered channel opening angles reverse osmosis

RELATIVE PRINCIPLE COMPONENT AND RELATIVE PRINCIPLE COMPONENT ANALYSIS ALGORITHM

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Journal of Electronics(China) 2007年第1期24卷 108-111页

作者： Wen Chenglin wang tianzhen Hu Jing Department of Automation Hangzhou Dianzi University Hangzhou 310018 China Department of Electrical Automation Shanghai Maritime University Shanghai 200135 China Department of Computer and Information Engineering Henan University Kaifeng 475001 China

In this letter,the new concept of Relative Principle Component (RPC) and method of RPC Analysis (RPCA) are put forward. Meanwhile,the concepts such as Relative Transform (RT),Ro-tundity Scatter (RS) and so on are introduced. This new method can overcome some disadvantages of the classical Principle Component Analysis (PCA) when data are rotundity scatter. The RPC selected by RPCA are more representative,and their significance of geometry is more notable,so that the application of the new algorithm will be very extensive. The performance and effectiveness are simply demonstrated by the geometrical interpretation proposed.

关键词： Relative Principle Component (RPC) Relative Transform (RT) Rotundity Scatter (RS)

A New Approach of Color Image Quantization

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通讯和计算机（中英文版） 2005年第3期2卷 72-76页

作者： HU Xinrong wang tianzhen LI Dehua Institute for Pattern Recognition and Artificial Intelligence State Education Commission Laboratory for Image Processing and Intelligence Control HuaZhong Univ. of Science＆Technology WuHan 430074 China Dept. of Computer Science ＆Technology Wuhan Institute of Science＆Technology WuHan 430074 China Institute of linage Processing WuHan Univ. of Technology Wuhan 430070China

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计算机视觉不需要重建

信息与控制 1999年第1期28卷 47-52页

作者：王天珍武汉汽车工业大学数字图象处理研究所

通过对ＣＶＧＩＰ杂志在１９９４组织的计算机视觉界有关３Ｄ重建理论论战的回顾和分析，得出结论：计算机视觉不需要重建。

关键词：计算机视觉 3D重建表象主动视觉

Comparative study of fault estimation for 3-DOF helicopter

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Comparative study of fault estimation for 3-DOF helicopter

计算机视觉与重建——计算机视觉理论界引人注目的争论

第三十九届中国控制会议

作者： Mengjie Lu Xiaoyuan Zhu tianzhen wang School of Logistics Engineering Shanghai Maritime University Merchant Marine College Shanghai Maritime University

Fault estimation plays an important role in health monitoring as well as fault tolerant control, which can help ensure the reliability and safety of helicopter system. As the helicopter is a typical nonlinear, strong coupling and unstable system, its fault estimation design is challenging. Besides, it is also of great risk and cost to conduct experimental validation of different fault estimation schemes for real helicopter system. Thus, this paper is intended to conduct comparative research of fault estimation for helicopter system with table-mount experimental platform. Based on helicopter’s dynamic model, four observer-based fault estimation approaches are presented, in which Luenberger observer, Kalman filter, unknown input observer, and modified proportional-integral-derivative observer design are adopted separately. For the modified proportional-integral-derivative observer based fault estimation design, measurement noise is specifically considered. Based on Quanser’s 3-DOF helicopter system, both simulation and experimental tests are carried out to show the performance differences of these fault estimation approaches.

关键词： fault estimation 3-DOF helicopter observer design comparative study

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模式识别与人工智能 1998年第3期11卷 300-304页

作者：王天珍武汉汽车工业大学数字图像处理研究所 430070

重建与目的之争是近年来计算机视觉理论界引人注目的争论。该文通过对由CVGIP杂志在1994年组织的计算机视觉界有关3D重建理论论战的回顾,得出结论:Edelman根据洛克对表象和概念的定义提出的建议:"无重建的表象也许是极端的目的主义者(Br... 详细信息

重建与目的之争是近年来计算机视觉理论界引人注目的争论。该文通过对由CVGIP杂志在1994年组织的计算机视觉界有关3D重建理论论战的回顾,得出结论:Edelman根据洛克对表象和概念的定义提出的建议:"无重建的表象也许是极端的目的主义者(Brooks)无表象的视觉与占统治地位的无目的的重建主义间的合理的折中",可能为计算机视觉研究摆脱困境找出一条可行的路。

关键词：计算机视觉 3D重建表象目的主义主动视觉

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直驱式永磁同步海流机叶轮不平衡的故障检测

电工技术学报 2018年第1期33卷 38-47页

作者：张米露王天真汤天浩 Yide wang 上海海事大学电气自动化系上海201306 南特大学CNRSUMR6164IETR 南特44000

针对波浪、湍流等影响下直驱式永磁同步海流机叶轮不平衡的故障检测,提出一种基于定子电流频率的故障特征分析方法。首先,该方法针对故障特征频率易被基波或噪声淹没的问题,采用总体最小二乘-旋转矢量不变技术(TLS-ESPRIT)估计电流瞬时... 详细信息

针对波浪、湍流等影响下直驱式永磁同步海流机叶轮不平衡的故障检测,提出一种基于定子电流频率的故障特征分析方法。首先,该方法针对故障特征频率易被基波或噪声淹没的问题,采用总体最小二乘-旋转矢量不变技术(TLS-ESPRIT)估计电流瞬时频率。其次,采用广义似然比检测(GLRT)方法设计不平衡故障检测器,通过分析检测器中变量,获取合适的监测量。最后,提出一种基于伸缩变换的数据标准化方法提取故障特征,解决同一故障在不同流速下故障特征多样的问题。理论分析、海流机仿真与海流样机实验结果验证了所提方法的有效性。该方法基于定子电流,易于实现,对于保证海流机安全高效运行以及减少维护费用等方面具有重要的实际意义。

关键词：海流发电直驱式永磁不平衡故障瞬时频率总体最小二乘-旋转矢量不变技术(TLS-ESPRIT)

基于相对主元分析的动态数据窗口故障检测方法

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电工技术学报 2013年第1期28卷 142-148页

作者：王天真刘远汤天浩陈炎上海海事大学电气自动化系上海200135 法国海军学院研究所SIG课题组布雷斯特29240

传统主元分析方法量纲标准化后常常无法进行有效的主元提取。基于相对主元分析故障检测方法,其控制限只与保留的主元个数和置信度有关,因而不能满足时变、非稳定的过程监控要求。针对这些问题,本文提出了基于相对主元分析的动态数据窗... 详细信息

传统主元分析方法量纲标准化后常常无法进行有效的主元提取。基于相对主元分析故障检测方法,其控制限只与保留的主元个数和置信度有关,因而不能满足时变、非稳定的过程监控要求。针对这些问题,本文提出了基于相对主元分析的动态数据窗口故障检测方法,该方法通过引入一个权值将传统构建控制限的方法和动态数据窗口相结合。最后应用到风力发电系统故障检测中,有效地检测出故障,并减少了误报情况。

关键词：相对主元分析 T2统计量动态数据窗口故障检测