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Single-phase-to-ground fault line selection in distribution networks based on similarity of wavelet energy spectrum

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Single-phase-to-ground fault line selection in distribution ...

Online Monitoring Research of Composite Insulator Based on Fibre Bragg Grating Sensor

2015 5th International Conference on Computer Sciences and Automation engineering(ICCSAE 2015)

作者： Mingjun Qi Qiang Zhong Liang Zhu Fangliang Gong Hua Leng State Grid Hunan Electric Power Company College of Electrical and Information engineering Hunan University

In order to solve the problems of ground fault line selection in distribution network, the article presents a fault line selection method based on the similarity of the wavelet packet energy spectrum. After extracting a certain data of transient fault zero-sequence current by the wavelet packet decomposition, we can get the energy spectrum distribution and energy spectrum matrix of all lines. Comparing the similarity of the energy spectrum distribution of all lines, a minimum similar principle as the criterion of the fault line is selected. Simulation results verified that this method can accurately and fast select the fault line with good adaptability.

关键词： fault line selection wavelet packet analysis similarity of energy spectrum

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Online Monitoring Research of Composite Insulator Based on F...

A Study on the Mobile Partial Discharge Locating System

2011 International Conference on Physics Science and Technology (ICPST 2011)

作者： Duanlei Yuan Yanhui Chen Hongwei Shi XiaoGuang Song Yundong Ji PingGao Group Co. Ltd School of Materials Science and engineering Wuhan University of Technology

Composite insulator has good insulation properties and mechanical properties. But under long-term electrical load and exposed to the sun and rain, its organic materials have aging problem, it is essential to test its operational state online. In this paper, the operational state of composite insulator were online detected by Fibre Bragg Grating（FBG） *** the process of making composite insulator, FBG sensor was embedded in this study. Firstly, composite insulators with FBG sensor exposed to accelerated aging, then artificial flashover imposed on composite insulator, the temperature of composite insulator were detected by FBG sensor, and the temperature field of pollution flashover was drawn. Test results indicate that the area where the flashover occured had high temperature, the silicone rubber surface significantly become black and hard, and had many small cracks, the hydrophobic of composite insulator basically loss. Studies show that FBG sensor has broad application prospects on online detection of composite insulator。

关键词： FBG composite insulator online monitoring

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Energy and Power engineering 2013年第4期5卷 589-592页

作者： Yan Yang Lin Tang Yue Hu Qian Wang Gaolin Wu tianchen Zhang Xiuchen Jiang Electric Power Research Institute of Chongqing Chongqing P.R.China Key Laboratory of Control of Power Transmission and Conversion Ministry of Education Shanghai Jiao Tong University Shanghai P.R.China

This paper studies on the Partial Discharge (PD) Locating System based on a mobile array of ultra-high frequency (UHF) antennas and a vehicle-mounted PD locating system is established. The system consists of omni-directional antenna array for receiving UHF PD signals, a pre-processing circuit for signal amplification and filtering and the high- speed acquisition and control unit of PD pulse signals. The developed locating system is able to simultaneously record the PD pulse signals received by the antenna array. By assessing the time difference of arrival (TDOA), the two-dimensional hyperbolic locating model quickly locates the PD source. Based on the software developed by LabVIEW, it is also possible to display, store and further analyze the acquired signals. Through the simulation of PD signals and the locating experiments with the system, it is proved that the PD locating system possesses the features of rapidity and precision in determining the bearing of PD source.

关键词： Partial Discharge Locating System Two-Dimensional Model Mobile

Function Analysis of the Enterprise Skills Training Center in the engineering Education Field

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Function Analysis of the Enterprise Skills Training Center i...

Enhanced electrical properties in bilayered ferroelectric thin films

2013年教育技术与管理科学国际会议

作者： Guihua Lin Tao Wang Grid maintenance training department State Grid of china Technology College

The excellent engineer education and cultivation program carried out by the Ministry of Education aims to cultivate a large number of superior technical talents of superb innovation ability and of high adaptability to the needs of economic and social development. Especially in the program "full-time professional master" launched in 2009, the cultivation of superior talents of engineering research ability and application ability was highly accentuated. This essay, aiming at some problems existing in the current engineering education field and based on the engineering education cooperation and practice of substation secondary equipment maintenance of State Grid of china Technology College-State Grid corporation of china skills training centre and Shandong university, explores the function of enterprise skills training center in the engineering education and the combination model of production, study and research. Moreover, this essay brings forward the feasible scheme for the next cooperation mode in the combination model of production and research of universities and enterprise skills training center and the engineering education development mode.

关键词： engineering education production, study and research combination state-owned enterprise skills training center

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Science china Chemistry 2013年第3期56卷 551-555页

作者： ZHANG Hao LONG WeiJie CHEN YaQing GUO DongJie Institute of Bio-inspired Structure and Surface engineering Nanjing University of Aeronautics and Astronautics Institute of NanoScience Nanjing University of Aeronautics and Astronautics

Sr2Bi4Ti5O18(SBTi) single layered and Sr2Bi4Ti5O18 /Pb(Zr0.53Ti0.47)O3(SBTi/PZT) bilayered thin films have been prepared on Pt/TiO2/SiO2/Si substrates by pulsed-laser deposition(PLD).The related structural characterizations and electrical properties have been comparatively investigated.X-ray diffraction reveals that both films have crystallized into perovskite phases and scanning electron microscopy shows the sharp *** films show well-saturated ferroelectric hysteresis loops,however,compared with the single layered SBTi films,the SBTi/PZT bilayered films have significantly increased remnant polarization(Pr) and decreased coercive field(Ec),with the applied field of 260 kV/*** measured Pr and Ec of SBTi and SBTi/PZT films were 7.9 C/cm 2,88.1 kV/cm and 13.0 C/cm 2,51.2 kV/cm,*** addition,both films showed good fatigue-free characteristics,the switchable polarization decreased by 9% and 11% of the initial values after 2.2 10 9 switching cycles for the SBTi single layered films and the SBTi/PZT bilayered films,*** results may provide some guidelines for further optimization of multilayered ferroelectric thin films.

关键词： bilayered films X-ray diffraction scanning electron microscopy ferroelectric properties

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通过脱碳控制全球平均温度

物理化学学报 2021年第5期37卷 186-192页

作者： Frits Mathias Dautzenberg 路勇徐彬 Serenix corporation 5632 Coppervein StreetFort CollinsCO 80528USA 华东师范大学化学与分子工程学院上海市绿色化学与化工过程绿色化重点实验室上海200062 易高卓新节能技术(上海)有限公司上海201109

建立能可靠预测全球平均温度(T_(e))的方法,对于寻求政治和全球合作以及大量财政资源来推动CO_(2)减排至关重要。基于可预见的若干年内CO_(2)排放量不能显著降低这一假设,目前的气候模型似乎都预测T_(e)将会持续上升。然而,将大气中的CO... 详细信息

建立能可靠预测全球平均温度(T_(e))的方法,对于寻求政治和全球合作以及大量财政资源来推动CO_(2)减排至关重要。基于可预见的若干年内CO_(2)排放量不能显著降低这一假设,目前的气候模型似乎都预测T_(e)将会持续上升。然而,将大气中的CO_(2)作为多因素地球气候系统的唯一变量,来关联观察到的温度异常,很可能过于简单化了,因为大气中H_(2)O的存在是至少应该要考虑的。受控于太阳活动的大气H_(2)O含量是T_(e)的首要决定因素,其次才是与人类活动相关的CO_(2)排放,而CO_(2)排放将来可能降低。基于地球平均温度观测值和热力学数据,建立了新的预测模型。应用该模型方程,可以分析过去、当前和未来大气中CO_(2)和H_(2)O含量并可计算出相应的T_(e)。这是一个还未见公开报道的、更精确的模型。本模型预测,依据将较基准情景(business-as-usual,BAU),到2050年T_(e)可能上升至15.5°C;通过合理的绿色技术行动方案,T_(e)可能降至约14.2°C,预测未来30年CO_(2)可减排513千兆吨。绿色技术应用场景包括诸如各种CO_(2)减排行动,碳捕获,矿化以及生物碳生产等,其中至2050年CO_(2)减排的主要贡献将来自于电力、农业和运输行业。另外,也对更激进的Plausible和Drawdown方案进行了分析,预测未来30年CO_(2)可分别减排1051和1747千兆吨,但这些方案可能会减少全球粮食生产。要强调的是,全球变暖的成因和预测应该视为开放的科学问题,因为涉及与全球变暖相关的物理过程的多个问题仍然无解。例如,太阳活动耦合米兰科维奇(Milankovitch)循环扮演的角色就没有完全理解。还有,海洋对CO_(2)的吸收和火山活动等其他因素的影响,可能无法忽略。

关键词：全球平均温度计算方法大气CO_(2)含量大气H2O含量全球变暖 CO_(2)减排

Environmental responsibility in sustainable business development

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化工新型材料 2010年第S1期38卷 12-12页

作者： Mark W. Irwin china National Bluestar (Group) Co. Ltd.

china National Bluestar (Group) Co. , Ltd. is a Chinese-foreign joint venture enterprise jointly funded by china National Chemical corporation (Chemchina) and The Blackstone Group. The business scope of Bluestar includes research, develop-ment, manufacturing and marketing of chemical new materials, animal nutrient additives, water treatment technologies and fine chemicals, as well as the provision of a diverse range of technology and engineering *** Company has experienced rapid development in size and internationalization in recent years and continues to invest in its business portfolio with significant emphasis on environmental responsibility as part of its commitment to Sustainable *** with the view of the global chemical industry, as represented by the International Council of Chemical Associations (ICCA), Sustainable Development will only come about if three goals-economic, environmental and society-related-can be recon-ciled. The products and services offered by Bluestar ultimately touches many aspects of peoples lives on a daily basis ranging from basic needs such as food, clothing and housing to more discretionary areas such as consumer electronics and leisure activities. In ad-dition Bluestar interacts as a solution provider to other industries for cleaning, equipment and engineering services. Through priori-tizing environmental responsibility in all aspects of its technology and product development and implementing disciplined practices in operations, the Company is setting ambitious goals for improving its efficiency, reducing risks to health and the environment and making better products which, in turn, help individual and industry *** of ongoing investment in targeted portfolio expansion, a commitment to broad-based innovation and proactive efforts to reduce the environmental footprint of the business at all levels will be shown to demonstrate key measures for ensuring that the e-conomic, environmental and soci

关键词： environmental responsibility sustainable development chemical new materials

Research on Microgrid and its Application in china

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Energy and Power engineering 2013年第4期5卷 171-176页

作者： Xing Wu Xiaogang Yin Quan Wei Yifan Jia Jing Wang Research and Development Center Xi'an High Voltage Apparatus Research Institute Co. Ltd Xi'an China

This paper presents the state of the art research and application of microgrid in china, and then introduces the major concerns for the development of microgrid. The research related to microgrid inchinaarose around 2004, focused on the connection of distributed energy resources (DERs) to grid and its influence on distribution network, and then followed the microgrid concept of Consortium for Electric Reliability Technology Solutions (CERTS). However, the microgrid inchinahas taken a more active path with the development of DER and the encouragement of the development of smart grid and resource and energy needing. Now, nearly every province inchinahas typical researches and applications of microgrid. Besides, there are already two major patterns in the development of microgrid, the institute-domi- nating research and the enterprise-dominating application. Research institutions likeTianjinUniversity, Hefei University of Technology, Xi’an Jiaotong University,InstituteofElectrical engineering(ChineseAcademyof Sciences), etc., are leading the research on microgrid. The companies like State Grid corporation of china (SGCC), china Southern Power Grid (CSPG), etc., have accomplished several demonstration projects of microgrid, and give a further boost to its application. At the end of the paper, according to the present situation of the development of microgrid inchina, the facing problems and the way to deal with it are put forward.

关键词： Microgrid Distributed Energy Resources Research Demonstration

Physical human-robot interaction estimation based control scheme for a hydraulically actuated exoskeleton designed for power amplification

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Frontiers of Information Technology & Electronic engineering 2018年第9期19卷 1076-1085页

作者： Yi LONG Zhi-jiang DU Wei-dong WANG Long HE Xi-wang MAO Wei DONG State Key Laboratory of Robotics and System Harbin Institute of Technolog Zhongshan Torch Group Co. Ltd Weapon Equipment Research Institute China South Industries Group Corporatio

We proposed a lower extremity exoskeleton for power amplification that perceives intended human motion via humanexoskeleton interaction signals measured by biomedical or mechanical sensors, and estimates human gait trajectories to implement corresponding actions quickly and accurately. In this study, torque sensors mounted on the exoskeleton links are proposed for obtaining physical human-robot interaction（pHRI） torque information directly. A Kalman smoother is adopted for eliminating noise and smoothing the signal data. Simultaneously, the mapping from the pHRI torque to the human gait trajectory is defined. The mapping is derived from the real-time state of the robotic exoskeleton during movement. The walking phase is identified by the threshold approach using ground reaction force. Based on phase identification, the human gait can be estimated by applying the proposed algorithm, and then the gait is regarded as the reference input for the controller. A proportional-integral-derivative control strategy is constructed to drive the robotic exoskeleton to follow the human gait trajectory. Experiments were performed on a human subject who walked on the floor at a natural speed wearing the robotic exoskeleton. Experimental results show the effectiveness of the proposed strategy.

关键词： Exoskeleton Physical human-robot interaction Torque sensor Human gait Kalman smoother