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Transient Stability Analysis of large-scale Power Systems:A Survey

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CSEE Journal of Power and Energy Systems 2023年第4期9卷 1284-1300页

作者： Qing-Hua Wu Yuqing Lin Chao Hong Yinsheng Su Tianhao Wen Yang Liu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China the Power Dispatching and Control Center China Southern Power GridGuangzhou 510530China

Transient stability analysis is a key problem in power system operation and planning.This paper aims at giving a comprehensive review on the modeling ideas and analysis methods for transient stability of large-scale power systems.For model construction,the general modeling of traditional power systems and special modeling for renewable generations and high-voltage direct-current transmissions are introduced.For transient stability analysis,Lyapunov based methods and non-Lyapunov based methods are thoroughly reviewed.In Lya-punov based methods,we focus on the energy function method,the sum-of-squares based method and decentralized stability analysis methods.Meanwhile,in non-Lyapunov based methods,the time-domain simulation,extended equal-area criterion and data-driven based methods are considered.The basic working principles,features and recent research progresses of all the above-mentioned methods are described in detail.In particular,their performances on several aspects,such as computational speed,conservativeness of stability region estimation or stability margin calculation,and adaptability to various types of system models,are mentioned.Finally,a brief discussion of potential directions for future research on transient stability analysis of large-scale power systems is included.Index Terms-connective stability,large-scale system analysis,Lyapunov functions,power systems,transient stability analysis.

关键词： connective stability large-scale system analysis Lyapunov functions power systems transient stability analysis

Fast topological pumping for the generation of large-scale Greenberger–Horne–Zeilinger states in a superconducting circuit

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Frontiers of physics 2022年第6期17卷 143-161页

作者： Jin-Xuan Han Jin-Lei Wu Zhong-Hui Yuan Yan Xia Yong-Yuan Jiang Jie Song School of Physics Harbin Institute of TechnologyHarbin 150001China Department of Optoelectronics Science Harbin Institute of TechnologyWeihai 264209China Department of Physics Fuzhou UniversityFuzhou 350002China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China Key Laboratory of Micro-Nano Optoelectronic Information System Ministry of Industry and Information TechnologyHarbin 150001China Key Laboratory of Micro-Optics and Photonic Technology of Heilongjiang Province Harbin Institute of TechnologyHarbin 150001China

Topological pumping of edge states in the finite lattice with nontrivial topological phases provides a powerful means for robust excitation transfer,requiring extremely slow evolution to follow an adiabatic transfer.Here,we propose fast topological pumping via edge channels to generate large-scale Greenberger–Horne–Zeilinger(GHZ)states in a topological superconducting circuit with a sped-up evolution process.The scheme indicates a conceptual way of designing fast topological pumping related to the instantaneous energy spectrum characteristics rather than relying on the shortcuts to adiabaticity.Based on fast topological pumping,large-scale GHZ states show greater robustness against on-site potential defects,the fluctuation of couplings and losses of the system in comparison with the conventional adiabatic topological pumping.With experimentally feasible qutrit-resonator coupling strengths and moderate decay rates of qutrits and resonators,fast topological pumping drastically improves the scalability of GHZ states with a high fidelity.Our work opens up prospects for the realization of large-scale GHZ states based on fast topological pumping in the superconducting quantum circuit system,which provides potential applications of topological matters in quantum information processing.

关键词： topological pumping superconducting ciruit large-scale Greenberger-Horne-Zeilinger states

Reproducible large-scale synthesis of surface silanized nanoparticles as an enabling nanoproteomics platform: Enrichment of the human heart phosphoproteome

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Nano Research 2019年第6期12卷 1473-1481页

作者： David S.Roberts Bifan Chen Timothy N.Tiambeng Zhijie Wu Ying Ge Song Jin Department of Chemistry University of Wisconsin-MadisonMadisonWisconsin 53706USA Department of Cell and Regenerative Biology University of Wisconsin-MadisonMadisonWisconsin 53705USA

A reproducible synthetic strategy was developed for facile large-scale (200 mg) synthesis of surface silanized magnetite (Fe3O4) nanoparticles (NPs) for biological applications.After further coupling a phosphate-specific affinity ligand,these functionalized magnetic NPs were used for the highly specific enrichment of phosphoproteins from a complex biological mixture.Moreover,correlating the surface silane density of the silanized magnetite NPs to their resultant enrichment performance established a simple and reliable quality assurance control to ensure reproducible synthesis of these NPs routinely in large scale and optimal phosphoprotein enrichment performance from batch-to-batch.Furthermore,by successful exploitation of a top-down phosphoproteomics strategy that integrates this high throughput nanoproteomics platform with online liquid chromatography (LC) and tandem mass spectrometry (MS/MS),we were able to specifically enrich,identify,and characterize endogenous phosphoproteins from highly complex human cardiac tissue homogenate.This nanoproteomics platform possesses a unique combination of scalability,specificity,reproducibility,and efficiency for the capture and enrichment of low abundance proteins in general,thereby enabling downstream proteomics applications.

关键词： nanoparticles nanoproteomics surface functionalization large-scale phosphoprotein enrichment top-down proteomics mass spectrometry

Research trend of large-scale supercomputers and applications from the TOP500 and Gordon Bell Prize

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Science China(Information Sciences) 2020年第7期63卷 128-141页

作者： Weimin ZHENG Department of Computer Science and Technology Tsinghua University

China is playing an increasingly important role in international supercomputing. In highperformance computing domain, there are two famous awards: The TOP500 list for the fastest 500 supercomputers in the world and the Gordon Bell Prize for the best HPC(high-performance computing)applications. China has been awarded in both TOP500 list and Gordon Bell Prize. In this paper, we review the supercomputers in the latest TOP500 list and seven Gordon Bell Prize applications to show the research trend of the large-scale supercomputers and applications. The first trend we observe is that heterogeneous architectures are widely used in the construction of supercomputing systems. The second trend is that artificial intelligence applications are expected to become one of the main stream applications of supercomputing.The third trend is that applying heterogeneous systems to complex scientific simulation applications will be more difficult.

关键词： TOP500 Gordon Bell Prize large-scale supercomputer

Comprehensive impact of as-cast microstructure and ordered structures on formability of large-scale Fe-6.5 wt.%Si alloy ingots

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Journal of Iron and Steel Research(International) 2020年第2期27卷 180-187页

作者： Xiang-ju Shi Yong-feng Liang Shi-bo Wen Zhi-yi Ding Bao Zhang Wei Song Feng Ye State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

large-scale Fe-6.5 wt.%Si ingot with excellent formability is required for a pilot line producing sheets through hot/cold rolling.The variation of the as-cast microstructure,ordered structures and the formability of the Fe-6.5 wt.%Si alloy ingots with the cooling rate during casting was investigated.Under air-cooling condition,inhomogeneous microstructures with a low proportion of equiaxed grains were formed,but the formation of ordered structures was partially inhibited,especially DO3.Homogeneous microstructures with a high proportion of equiaxed grains were observed under the condition of furnace cooling,but the ordered structures were fully generated,and the degree of order is high.It is generally believed that high degree of order is the main factor of brittleness,but the homogeneous microstructure(including grain morphology and size)of the furnace-cooled sample helps to improve the formability.The influence of these two aspects on formability is contradictory.Therefore,the formability is tested through the flow stress during the compression and the microstructure after the compression.The results show that the furnace-cooled sample has better formability.For large-scale ingots,the control of as-cast microstructure becomes more significant than the control of degree of order.Slow cooling during casting is important for the large-scale ingots to have good formability meeting the requirements of direct hot rolling.

关键词： large-scale ingot Fe-6.5 wt.%Si alloy Cooling method Formability Ordered structure As-cast microstructure

Capture-aware Bayesian RFID Tag Estimate for large-scale Identification

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 119-127页

作者： Haifeng Wu Yang Wang Yu Zeng School of Electrical and Information Technology Yunnan Minzu University

Dynamic framed slotted Aloha algorithm is one of popular passive radio frequency identification(RFID) tag anticollision algorithms. In the algorithm, a frame length requires dynamical adjustment to achieve higher identification efficiency.Generally, the adjustment of the frame length is not only related to the number of tags, but also to the occurrence probability of capture effect. Existing algorithms could estimate both the number of tags and the probability of capture effect. Under large-scale RFID tag identification, however, the number of tags would be much larger than an initial frame length. In this scenario, the existing algorithm's estimation errors would substantially increase. In this paper, we propose a novel algorithm called capture-aware Bayesian estimate, which adopts Bayesian rules to accurately estimate the number and the probability simultaneously. From numerical results, the proposed algorithm adapts well to the large-scale RFID tag identification. It has lower estimation errors than the existing algorithms. Further,the identification efficiency from the proposed estimate is also higher than the existing algorithms.

关键词： Aloha Bayesian capture effect large-scale radio frequency identification(RFID)

A numerical study on flame and large-scale flow structures in bluff-body stabilized flames

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Chinese Journal of Aeronautics 2019年第7期32卷 1646-1656页

作者： Jing CHEN Hua ZHOU Zhuyin REN Center for Combustion Energy Tsinghua UniversityBeijing100084China School of Aerospace Engineering Tsinghua UniversityBeijing100084China

large Eddy Simulations(LES) in conjunction with the Flamelet Progress Variable(FPV) approach have been performed to investigate the flame and large-scale flow structures in the bluff-body stabilized non-premixed flames, HM1 and HM3. The validity of the numerical methods is first verified by comparing the predicted velocity and composition fields with experimental measurements. Then the evolution of the flame and large-scale flow structures is analyzed when the flames approach blow-off. The analysis of instantaneous and statistical data indicates that there exists a shift of the control mechanism in the recirculation zone in the two flames. In the recirculation zone, HM1 flame is mainly controlled by the mixing effect and ignition mainly occurs in the outer shear layer. In HM3 flame, both the chemical reactions and mixing are important in the recirculation zone. The Proper Orthogonal Decomposition(POD) results show that the fluctuations in the outer shear layer are more intense in HM1, while the flow structures are more obvious in the outer vortex structure in HM3, due to the different control mechanism in the recirculation zone.It further shows that the flow structures in HM1 spread larger in the intense mixing zone due to higher temperature and less extinction.

关键词： Bluff-body stabilized flames large Eddy Simulation(LES) large-scale flow structures Proper Orthogonal Decomposition(POD)

A Modified Three-Term Conjugate Gradient Algorithm for large-scale Nonsmooth Convex Optimization

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Computers, Materials & Continua 2020年第2期62卷 787-800页

作者： Wujie Hu Gonglin Yuan Hongtruong Pham College of Mathematics and Information Science Guangxi UniversityNanningChina Thai Nguyen University of Economics and Business Administration Thai NguyenVietnam

It is well known that Newton and quasi-Newton algorithms are effective to small and medium scale smooth problems because they take full use of corresponding gradient function’s information but fail to solve nonsmooth problems.The perfect algorithm stems from concept of‘bundle’successfully addresses both smooth and nonsmooth complex problems,but it is regrettable that it is merely effective to small and medium optimization models since it needs to store and update relevant information of parameter’s bundle.The conjugate gradient algorithm is effective both large-scale smooth and nonsmooth optimization model since its simplicity that utilizes objective function’s information and the technique of Moreau-Yosida regularization.Thus,a modified three-term conjugate gradient algorithm was proposed,and it has a sufficiently descent property and a trust region character.At the same time,it possesses the global convergence under mild assumptions and numerical test proves it is efficient than similar optimization algorithms.

关键词： Conjugate gradient large-scale trust region global convergence

Mean-field Macro Computation in large-scale Cloud Service Systems with Resource Management and Job Scheduling

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Journal of Systems Science and Systems Engineering 2019年第2期28卷 238-261页

作者： Feifei Yang Yanping Jiang Quanlin Li School of Business Administration Northeastern University Shenyang 110167 China School of Economics and Management Beijing University of Technology Beijing 100124 China

Service computing is an emerging and distributed computing mode in cloud service systems, and has become an interesting research direction for both academia and industry. Note that the cloud service systems always display new characteristics, such as stochasticity, large scale, loose coupling, concurrency non-homogeneity and heterogeneity;thus their load balancing investigation has been more interesting, difficult and challenging until now. By using resource management and job scheduling, this paper proposes an integrated, real-time and dynamic control mechanism for large-scale cloud service systems and their load balancing through combining supermarket models with not only work stealing models but also scheduling of public reserved resource. To this end, this paper provides a novel stochastic model with weak interactions by means of nonlinear Markov processes. To overcome theoretical difficulties growing out of the state explosion in high-dimensional stochastic systems, this paper applies the mean-field theory to develop a macro computational technique in terms of an infinite-dimensional system of mean-field equations. Furthermore, this paper proves the asymptotic independence of the large-scale cloud service system, and show how to compute the fixed point by virtue of an infinite-dimensional system of nonlinear equations. Based on the fixed point, this paper provides effective numerical computation for performance analysis of this system under a high approximate precision. Therefore, we hope that the methodology and results given in this paper can be applicable to the study of more general large-scale cloud service systems.

关键词： large-scale cloud service system resource management job scheduling supermarket model work stealing model scheduling of public reserved resource