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直流偏磁对500 kV变压器振动特性的影响分析

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电力自动化设备 2024年第2期44卷 133-138页

作者：何良吴天宝李荣丁登伟杨洁李盛涛清华四川能源互联网研究院四川成都610213 国网四川省电力公司电力科学研究院四川成都610072 成都航空职业技术学院四川成都610100 西安交通大学电气工程学院陕西西安710049

特高压直流工程单极-大地回路运行时,直流电流侵入大型变压器绕组,致使变压器振动加剧。为了深入了解直流偏磁对大型变压器振动特性的影响,分析了变压器的振动机理及直流偏磁的影响机制。在白鹤滩—江苏±800 kV特高压直流输电工程调试... 详细信息

特高压直流工程单极-大地回路运行时,直流电流侵入大型变压器绕组,致使变压器振动加剧。为了深入了解直流偏磁对大型变压器振动特性的影响,分析了变压器的振动机理及直流偏磁的影响机制。在白鹤滩—江苏±800 kV特高压直流输电工程调试期间,对500 kV三相变压器的中性点电流、振动信号进行了实测,量化了直流偏磁程度,分析了不同直流偏磁程度下变压器振动信号时域及频谱特征。提取了波形畸变比、奇偶次谐波能量比、累计能量占比、功率谱熵等特征量来分析直流偏磁对大型变压器振动特性的影响。结果表明:直流偏磁导致波形畸变,1个工频周期内2个半周期对应的振动波形不再对称分布;随着直流偏磁程度增加,振动信号主频分量改变,50 Hz倍频谐波分量增多,其中50 Hz奇次谐波增幅要大于偶次谐波,且影响主要集中在600 Hz以内;由于铁心饱和作用,直流偏磁增大到一定程度时,磁不平衡性降低,振动信号复杂度不再增加。

关键词：特高压直流输电直流偏磁电力变压器振动特性

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蒙古语大众媒体研究现状及面临的问题

蒙古学研究（蒙文版） 2024年第2期 73-77,124页

作者：吴田宝吴斯日古楞不详

In the extensive history of our country's development,Mongolian mass media has consistently been a significant topic within the field of *** a result,academic achievements in the study of Mongolian mass media have progressively accumulated and *** paper primarily offers an in-depth analysis of the current status of Mongolian mass media research,based on the works of renowned domestic and international journalism experts and their representative ***,it identifies several issues within this research field,underscores the"blind spots,"and proposes research topics and suggestions to advance studies in this area.

关键词：大众媒体蒙古语 primarily

Analysis of one dimensional and two dimensional fuzzy controllers

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Journal of Systems Engineering and Electronics 2006年第2期17卷 362-373页

作者： Ban Xiaojun Gao Xiaozhi Huang Xianlin wu tianbao Dept. of Control Theory and Engineering Harbin Inst. of Technology Harbin 150001 P. R. China Inst. of Intelligent Power Electronics Helsinki Univ. of Technology Espoo Finland

The analytical structures and the corresponding mathematical properties of the one dimensional and two dimensional fuzzy controllers are first investigated in detail. The nature of these two kinds of fuzzy controllers is next probed from the perspective of control engineering. For the one dimensional fuzzy controller, it is concluded that this controller is a combination of a saturation element and a nonlinear proportional controller, and the system that employs the one dimensional fuzzy controller is the combination of an open-loop control system and a closedloop control system. For the latter case, it is concluded that it is a hybrid controller, which comprises the saturation part, zero-output part, nonlinear derivative part, nonlinear proportional part, as well as nonlinear proportional-derivative part, and the two dimensional fuzzy controller-based control system is a loop-varying system with varying number of control loops.

关键词： one dimensional fuzzy controller two dimensional fuzzy controller analytical structures fuzzy inference control system analysis.

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耐张塔输电线路等值覆冰厚度的简化预测方法

四川电力技术 2024年第1期47卷 10-14,42页

作者：吴天宝马小敏刘益岑刘小江庄杰国网四川省电力公司电力科学研究院四川成都610041 电子科技大学信息与通信工程学院四川成都611731

输电线路覆冰会引发断线倒塔事故,严重影响电网的安全运行,准确监测线路覆冰情况具有重要的工程意义和应用价值。在输电线路综合荷载的静力学模型基础上,提出了两种简化的等值覆冰厚度预测方法。第一种简化方法不需要水平档距和高度差参... 详细信息

输电线路覆冰会引发断线倒塔事故,严重影响电网的安全运行,准确监测线路覆冰情况具有重要的工程意义和应用价值。在输电线路综合荷载的静力学模型基础上,提出了两种简化的等值覆冰厚度预测方法。第一种简化方法不需要水平档距和高度差参数,减少了输入参数;第二种简化方法不需要角度传感器,避免角度传感器误差造成的预测性能下降,且减小了系统的硬件成本。结果表明:在大水平档距情况下,第一种简化方法与现有方法的预测性能基本一致;在覆冰前后悬垂角变化不大的情况下,第二种简化方法的预测误差在工程允许范围以内。

关键词：等值覆冰厚度耐张塔简化预测方法静态力学模型悬垂角

Multiphase Interfacial Regulation Based on Hierarchical Porous Molybdenum Selenide to Build Anticorrosive and Multiband Tailorable Absorbers

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Nano-Micro Letters 2024年第1期16卷 85-105页

作者： tianbao Zhao Zirui Jia Jinkun Liu Yan Zhang Guanglei wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071People’s Republic of China

Electromagnetic wave(EMW)absorbing materials have an irreplaceable position in the field of military stealth as well as in the field of electromagnetic pollution *** in order to cope with the complex electromagnetic environment,the design of multifunctional and multiband high efficiency EMW absorbers remains a tremendous *** this work,we designed a three-dimensional porous structure via the salt melt synthesis strategy to optimize the impedance matching of the ***,through interfacial engineering,a molybdenum carbide transition layer was introduced between the molybdenum selenide nanoparticles and the three-dimensional porous carbon matrix to improve the absorption behavior of the *** analysis indicates that the number and components of the heterogeneous interfaces have a significant impact on the EMW absorption performance of the absorber due to mechanisms such as interfacial polarization and conduction loss introduced by interfacial ***,the prepared MoSe_(2)/MoC/PNC composites showed excellent EMW absorption performance in C,X,and Ku bands,especially exhibiting a reflection loss of−59.09 dB and an effective absorption bandwidth of 6.96 GHz at 1.9 *** coordination between structure and components endows the absorber with strong absorption,broad bandwidth,thin thickness,and multi-frequency absorption ***,it can effectively reinforce the marine anticorrosion property of the epoxy resin coating on Q235 steel *** study contributes to a deeper understanding of the relationship between interfacial engineering and the performance of EMW absorbers,and provides a reference for the design of multifunctional,multiband EMW absorption materials.

关键词： Interfacial engineering Anticorrosion Multiband Electromagnetic wave absorber

Migrant Farmer-Workers Becoming New City Residents

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The Journal of Human Rights 2005年第3期4卷 33-35页

作者： wu tianbao & CHANG ZHENG

The investigation group of the China Society for Human Rights Studies (CSHRS) went on a study tour of Shanghai Municipality and wuxi, Zhenjiang and Changzhou of Jiangsu Province June 23-30, 2004 and found that the four cities had made gratifying achievements in protecting the rights and interests of migrant farmer workers and a large number of such workers are becoming new city residents of a number of cities

关键词： than more work In Migrant Farmer-Workers Becoming New City Residents

Self-assembly tungsten selenide hybrid ternary MOF derived magnetic alloys via multi-polarization to boost microwave absorption

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Nano Research 2024年第3期17卷 1625-1635页

作者： tianbao Zhao Tingting Zheng Di Lan Yan Zhang Zhengshuo Sun Chao Wang Zirui Jia Guanglei wu Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China

Confronted with severe electromagnetic wave pollution,the development of high-performance electromagnetic wave shielding or absorbing materials is an effective way to deal with ***,double transition metal alloys and transition metal dichalcogenides have attracted extensive attention in electromagnetic wave absorption,but few reports have studied the effects of these two materials on electromagnetic wave absorption at the same *** this work,cobalt-based alloy with magnetic loss mechanism was selected for composition *** ternary metal-organic framework was prepared by the one-step method,and then CoCu/C was prepared by high temperature ***,in the hydrothermal process,ultra-thin tungsten selenide nanosheets were coated on the surface of magnetic component,and the final polyhedral WSe_(2)/CoCu/C composites with multiple heterogeneous interfaces were *** synergistic effect of dielectric and magnetic components optimizes impedance matching and allows more electromagnetic waves to enter the ***,through the conduction loss of high conductivity graphitized carbon,interfacial polarization,and dipole polarization of heterogeneous interfaces between the components,the magnetic loss provided by CoCu alloy can work together to maximize the attenuation ability of electromagnetic ***,the minimum reflection loss(RLmin)value of the composite reaches-53.43 dB when the matched thickness is 2.1 mm,while the maximum effective absorption bandwidth(EABmax)reaches 6.0 GHz at a thin thickness of 1.8 *** work provides some support and reference for the design of novel electromagnetic wave absorbing materials via the dielectric/magnetic loss synergistic mechanism.

关键词： metal-organic framework dielectric/magnetic loss transition metal dichalcogenide electromagnetic wave absorption

臭氧和好氧生物法处理污水处理厂出水的纳米过滤浓缩液

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中国环境科学 1998年第4期18卷 353-355页

作者：蹇兴超吴天宝 Mathias Ernst 清华大学核能技术设计研究院德国柏林工业大学水质控制系

城市污水处理厂出水的纳米过滤浓缩液较难直接生物处理。臭氧氧化该浓缩液降低ＤＯＣ的速度较慢，但是可以有效地破坏该浓缩液中含苯环和有色基团的大分子有机物，显著增加小分子有机物的相对含量，从而增大其可生化降解性能。研究发现... 详细信息

城市污水处理厂出水的纳米过滤浓缩液较难直接生物处理。臭氧氧化该浓缩液降低ＤＯＣ的速度较慢，但是可以有效地破坏该浓缩液中含苯环和有色基团的大分子有机物，显著增加小分子有机物的相对含量，从而增大其可生化降解性能。研究发现臭氧的投量为５２ｍｇ／Ｌ左右时，臭氧化改善该纳米过滤浓缩液的可生化降解性能的效果最佳。

关键词：过滤氧化好氧生物处理污水处理厂废水处理

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蒙古语大众媒体发展趋势研究

中国蒙古学（蒙文） 2021年第1期49卷 157-164页

作者：吴田宝不详