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Multi-area Frequency-constrained Unit Commitment for Power Systems with High Penetration of Renewable Energy Sources and Induction Machine Load

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 754-766页

作者： Leibao Wang Hui Fan Jifeng liang Longxun Xu tiecheng li Peng Luo Bo Hu Kaigui Xie the State Grid Hebei Electric Power Research Institute Shijiazhuang 050021China State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400044China

The increasing penetration of renewable energy sources(RESs)brings great challenges to the frequency security of power *** traditional frequency-constrained unit commitment(FCUC)analyzes frequency by simplifying the average system frequency and ignoring numerous induction machines(IMs)in load,which may underestimate the risk and increase the operational *** this paper,we consider a multiarea frequency response(MAFR)model to capture the frequency dynamics in the unit scheduling problem,in which regional frequency security and the inertia of IM load are modeled with high-dimension differential algebraic equations.A multi-area FCUC(MFCUC)is formulated as mixed-integer nonlinear programming(MINLP)on the basis of the MAFR ***,we develop a multi-direction decomposition algorithm to solve the MFCUC *** original MINLP is decomposed into a master problem and *** subproblems check the nonlinear frequency dynamics and generate linear optimization cuts for the master problem to improve the frequency security in its optimal *** studies on the modified IEEE 39-bus system and IEEE 118-bus system show a great reduction in operational ***,simulation results verify the ability of the proposed MAFR model to reflect regional frequency security and the available inertia of IMs in unit scheduling.

关键词： Decomposition algorithm frequency response frequency-constrained unit commitment induction machine multi-area mixed-integer nonlinear programming(MINLP)

Application of Hankel Dynamic Mode Decomposition for Wide Area Monitoring of Subsynchronous Resonance

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Energy Engineering 2023年第4期120卷 851-867页

作者： Lei Wang tiecheng li Hui Fan Xuekai Hu lin Yang Xiaomei Yang State Grid Hebei Electric Power Research Institute Shijiazhuang050021China State Grid Hebei Electric Power Company Shijiazhuang050021China The College of Electrical Engineering Sichuan UniversityChengdu610065China

In recent years,subsynchronous resonance(SSR)has frequently occurred in DFIG-connected series-compensated *** the analysis and prevention,it is of great importance to achieve wide area monitoring of the *** paper presents a Hankel dynamic mode decomposition(DMD)method to identify SSR parameters using synchrophasor *** basic idea is to employ the DMD technique to explore the subspace of Hankel matrices constructed by *** is analytically demonstrated that the subspace of these Hankel matrices is a combination of fundamental and SSR ***,the SSR parameters can be calculated once the modal parameter is *** with the existing method,the presented work has better dynamic performances as it requires much less ***,it is more suitable for practical cases in which the SSR characteristics are *** effectiveness and superiority of the proposed method have been verified by both simulations and field data.

关键词： Hankel dynamic mode decomposition time-varying sub-synchronous oscillation synchrophasor

A Design of 220 kV line Protection Action Deduction System Based on Numerical Simulation

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Energy Engineering 2022年第5期119卷 2105-2134页

作者： tiecheng li Qingquan liu Hui Fan Xianzhi Wang Daming Zhou Junan Guo Lee li Kun Zhou Yujie Hu State Grid Hebei Electrical Power Company Research Institute Shijiazhuang050021China State Grid Hebei Electrical Power Company Shijiazhuang050021China Wuhan Kemov Electric Co. Ltd.Wuhan430223China

Accurate conditions monitoring and early wrong action warnings of relay protection in the Smart Substation is the basic guarantee to realize the normal operation of primary and secondary system of the power *** present,the traditional operation and maintenance monitoring methods of relay protections have poor timeliness,while some automatic monitoring methods have insufficient early warning performance,and lack the online action deduction function independent of the actual *** this paper,a design method of integrated action deduction system including protection logic reasoning and software and hardware operation condition is *** system can receive real-time operation information of protection online,simulate different types of faults,and output the recording information of sub modules belongs to the action deduction *** can realize the online monitoring of device faults such as deducing the correctness of setting values at a certain time in the future,giving the wrong action warnings and predicting the probability of them as well,which effectively improves the operation and maintenance efficiency of the secondary system in the intelligent substation.

关键词： Intelligent substation numerical simulation relay protection conditions monitoring wrong action warning

United Nations and Human Rights

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The Journal of Human Rights 2002年第3期1卷 34-39页

作者： li tiecheng AND liU CHANGMIN

Charter and Universal Declaration Human rights problem has aroused serious concem from the international community. It was originated in the Second World War. Fascists of Germany, Italy and Japan committed genocide and crimes of killing innocents and it became a matter of worldwide concem to defend the right to life. The war between the anti-fascist alliance against the axis powers including Germany and Japan was in fact a war of protecting the dignity and rights of humanity and a war to defend human rights and for national independence. The programmatic document Charter of the Atlantic of the alliance during the war and the Declaration of the United Nations all clearly put forward the idea that defending human rights is

关键词： United Nations and Human Rights UN

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厚板的高阶剪切变形理论研究

力学学报 2016年第5期48卷 1096-1113页

作者：段铁城李录贤西安交通大学航天航空学院/机械结构强度与振动国家重点实验室西安710049

已有多种厚板理论和高阶剪切变形模型,但仍需要进一步研究以更加完善.首先根据平均转角及上下表面剪应力自由这两个条件,提出了具有统一高阶剪切变形模型的中面位移模式,并将之表示为正交分解形式.根据正交特性,定义了板的广义应力;运... 详细信息

已有多种厚板理论和高阶剪切变形模型,但仍需要进一步研究以更加完善.首先根据平均转角及上下表面剪应力自由这两个条件,提出了具有统一高阶剪切变形模型的中面位移模式,并将之表示为正交分解形式.根据正交特性,定义了板的广义应力;运用板问题应变能密度表示的等价性,提出了与广义应力功共轭的广义应变表示形式,建立了板的本构关系.证明了不同转角定义时虚功原理板理论表示的客观性,以及与三维弹性理论表示的等价性.运用虚功原理,建立了变分自洽的高阶厚板理论和变分渐近的低阶厚板理论,推导了相应的平衡方程及边界条件,分析了与已有板理论的异同.以广义应力形式建立了厚板理论的平衡方程,厘清了不同转角表示时板理论间的关系、低阶厚板理论与高阶厚板理论间的关系以及剪切系数计算等若干基本问题.对圣维南扭转问题的求解证明了该理论的正确性.

关键词：统一高阶剪切变形模型广义应力广义应变虚功原理高阶理论低阶理论

Primary lung clear cell carcinoma:one case report

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The Chinese-German Journal of Clinical Oncology 2009年第4期8卷 240-241页

作者： li Duan tiecheng Pan Xiang Wei Min Hu Department of Cardiac and Thoracic Surgery Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Case report The patient was male, 64 years old, admitted to hospital due to Repeatedly cough for two months. Two months ago in the patients with no obvious incentive to appear repeatedly coughing, without sputum, no chest tightness, chest pain or fever symptoms such as. Chest X-ray examination suggested that the right middle lung of a huge high-density mass shadow, measuring about 9 cm, fuzzy edge, density uniformity （Fig. 1）. Chest CT suggested that the great mass of right middle lobe, was lobulated mass, mediastinal lymph node enlargement did not found （Fig. 2）. Fiberoptic bronchoscopy could be seen right middle lobe lateral segment had a thing blocking the lumen,

关键词：原发性肺透明细胞癌病例报告纤维支气管镜检查纵隔淋巴结肿大反复咳嗽右肺中叶胸部CT 中叶肺癌

基于自适应频率选择的OTHR多模传播抑制研究

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电波科学学报 2013年第4期28卷 686-691页

作者：李铁成李雪冯静鲁转侠中国电波传播研究所山东青岛266107

因电离层分层特性使OTHR回波信号经历多模传播,引起地海杂波频谱大幅度展宽,导致OTHR对舰船目标的检测能力急剧下降.文中提出了基于全频段定频探测的单模工作频率选择方法,指出该方法的核心问题是返回散射定频探测传播模式数目随距离分... 详细信息

因电离层分层特性使OTHR回波信号经历多模传播,引起地海杂波频谱大幅度展宽,导致OTHR对舰船目标的检测能力急剧下降.文中提出了基于全频段定频探测的单模工作频率选择方法,指出该方法的核心问题是返回散射定频探测传播模式数目随距离分布信息的获取.提出一种基于特征分解的传播模式数目提取算法,实现了全频段下传播模式数目分布提取,从而最终实现单模式工作频率选择.经仿真研究和试验数据验证,上述方法有效.

关键词：电离层多模传播频率选择返回散射定频探测