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大规模光伏经柔直送出系统的近工频耦合振荡机理与特性分析

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电力自动化设备 2024年第8期44卷 70-76页

作者：彭茂兰许诘翊严喜林张楠谢小荣中国南方电网有限责任公司超高压输电公司电力科研院广东广州510663 清华大学电机系新型电力系统运行与控制全国重点实验室北京100084

针对近工频耦合振荡这类新型振荡稳定性问题,研究了其发生机理和稳定特性。建立大规模光伏经柔直送出系统的全电磁暂态模型,仿真展示了近工频耦合振荡的发生条件。通过分析设备在振荡频率下的复功率分布,阐明系统振荡源头与传播特性。... 详细信息

针对近工频耦合振荡这类新型振荡稳定性问题,研究了其发生机理和稳定特性。建立大规模光伏经柔直送出系统的全电磁暂态模型,仿真展示了近工频耦合振荡的发生条件。通过分析设备在振荡频率下的复功率分布,阐明系统振荡源头与传播特性。基于在线阻抗分析研究振荡发生的电路机理,分析影响振荡稳定性的关键因素。结果表明,在次/超同步近工频段,光伏电站表现为电阻为负的容性元件,与柔直送端换流站、输电线路共同构成负阻尼的串联谐振电路,从而引发不稳定的近工频耦合振荡;光伏网侧换流器、柔直换流器控制参数和输电线路电抗等因素会影响系统的稳定性。

关键词：光伏并网构网型控制柔性直流输电近工频耦合振荡阻抗模型

Interconnection and Damping Assignment Passivity-Based Excitation Control of Power Systems

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Interconnection and Damping Assignment Passivity-Based Excit...

General theory for designing phonon transport in alloyed/doped materials

2010 Chinese Control and Decision Conference

作者： Jianyong Li~1,Yanhong Liu~2,Chunwen Li~3,Lijun zhang~4 1.School of Computer & Communication engineering,Zhengzhou university of Light Industry,Zhengzhou 450002,P.R.china 2.School of Electrical engineering,Zhengzhou university,Zhengzhou 450001,P.R.china 3.department of automation,Tsinghua university,Beijing 100084,P.R.china 4.School of automation,harbin engineering university,harbin 150001,P.R.china

＜正＞Interconnection and damping assignment passivity-based control（IDA-PBC） is a technique that regulates the behavior of nonlinear systems by assigning a desired port-controlled Hamiltoman *** this paper,based on the original dissipative Hamiltonian realization of a single-machine-infinite-bus power system,we design a controller to re-formulate the interconnection matrix and stabilize the power *** result verifies the effectiveness of the proposed control scheme.

关键词： Interconnection and damping assignment passivity-based control power systems excitation control stabilization

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Science china(Physics,Mechanics & Astronomy) 2024年

作者： Chenhan Liu Chao Wu Wei Liu Yunshan Zhao Gang zhang Hongmin Yang Yunfei Chen Micro-and Nano-scale Thermal Measurement and Thermal Management Laboratory Key Laboratory of Numerical Simulation for Large Complex Systems Ministry of Education School of Energy and Mechanical Engineering Nanjing Normal University School of Electrical and automation engineering Nanjing Normal University Phonon engineering Research Center of Jiangsu Province Center for Quantum Transport and Thermal Energy Science Institute of Physics Frontiers and Interdisciplinary Sciences School of Physics and Technology Nanjing Normal University Institute of High-Performance Computing Agency for Science Technology and ResearchSingapore Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments School of Mechanical Engineering Southeast University

Alloying/doping is a widely used technique for improving the electrical, mechanical, and optical properties of ***, this technology induces significant distortions in the lattice structure, mass distribution, and potential field, greatly enhancing phonon scattering. Here, we introduce the concept of alloying/doping path and employ crystal symmetry, lattice deformation, and electron distribution to characterize it. Based on this new concept, the phonon thermal transport behavior in alloyed/doped materials can be well designed, and along different alloying/doping paths, the difference in thermal conductivity can be up to 45 times. On one hand, strategic alloying/doping that combines high crystal symmetry, large lattice contraction, and the same electron distribution suppresses phonon-phonon scattering phase space, induces phonon stiffening, and bolsters electronic structure symmetry, respectively. These synergistic effects significantly improve thermal conductivity. On the other hand, random alloying/doping has a low symmetry, leading to the typical “U” shape of alloying/doping level-dependent thermal conductivity. Our theory is corroborated in three-dimensional（3D） Si, 2D MoS2, and quasi-1D TiS3, affirming its efficacy and broad applicability in controlling phonon transport.

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无人飞行器在不确定扰动下的动态目标跟踪

engineering 2024年第4期35卷 74-85页

作者： Yanjie Chen Yangning Wu Limin Lan Hang Zhong zhiqiang Miao Hui zhang Yaonan Wang School of Mechanical engineering and automation Fuzhou UniversityFuzhou 350108China department of Computer Science Aberystwyth UniversityAberystwyth SY233DBUK School of Robotics Hunan UniversityChangsha 410082China College of Electrical and Information engineering Hunan UniversityChangsha 410082China National engineering Research Center of Robot Visual Perception and Control Technology Hunan UniversityChangsha 410082China

This study proposes an image-based visual servoing(IBVS)method based on a velocity observer for an unmanned aerial vehicle(UAV)for tracking a dynamic target in Global Positioning System(GPS)-denied *** proposed method derives the simplified and decoupled image dynamics of underactuated UAVs using a constructed virtual camera and then considers the uncertainties caused by the unpredictable rotations and velocities of the dynamic target.A novel image depth model that extends the IBVS method to track a rotating target with arbitrary orientations is *** depth model ensures image feature accuracy and image trajectory smoothness in rotating target *** relative velocities of the UAV and the dynamic target are estimated using the proposed velocity *** to the velocity observer,translational velocity measurements are not required,and the control chatter caused by noise-containing measurements is *** integral-based filter is proposed to compensate for unpredictable environmental disturbances in order to improve the antidisturbance *** stability of the velocity observer and IBVS controller is analyzed using the Lyapunov *** simulations and multistage experiments are conducted to illustrate the tracking stability,anti-disturbance ability,and tracking robustness of the proposed method with a dynamic rotating target.

关键词： Unmanned aerial vehicle Visual servoing Velocity observer Target tracking

Adaptive Control of Time Delay Nonlinear Systems with Unknown Control Direction

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Adaptive Control of Time Delay Nonlinear Systems with Unknow...

Solar-driven photothermal catalytic CO_(2) conversion:a review

2010 Chinese Control and Decision Conference

作者： Tianping zhang~1,Hui wen~1,Qiuqin zhu~1 1.department of automation,College of Information engineering,Yangzhou university,Yangzhou 225009,china

In this paper,robust adaptive control is proposed for a class of time delay nonlinear systems with unknown constant control gain and control *** design is based on the principle of sliding mode control and the use of Nussbaum-type function in solving the problem of the completely unknown control *** unknown function and the upper bound of the unknown time delay term are assumed to be in the form of nonlinear functions with unknown *** uncertain time delay terms are compensated for using appropriate Lyapunov- Krasovskii functional and Young’s inequality in the *** closed-loop control system is proved to be semi-globally uniformly ultimately *** results demonstrate the effectiveness of the approach.

关键词： Adaptive Control Nonlinear Systems Time-varying Delay Nussbaum-type Function

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Rare Metals 2024年第7期43卷 2913-2939页

作者： Bachirou Guene Lougou Bo-Xi Geng Ru-Ming Pan Wei Wang Tian-Tian Yan Fang-Hua Li Hao zhang Oraléou SanguéDjandja Yong Shuai Meisam Tabatabaei Daniel Sabi Takou School of Energy Science and engineering Harbin Institute of TechnologyHarbin 150001China MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150090China School of Electrical engineering and automation Harbin Institute of TechnologyHarbin 150001China Guangdong Provincial Key Laboratory of Distributed Energy Systems Engineering Research Center of None-Food Biomass Efficient Pyrolysis and Utilization Technology of Guangdong Higher Education InstitutesDongguan University of TechnologyDongguan 523808China Higher Institution Centre of Excellence(HICoE) Institute of Tropical Aquaculture and Fisheries(AKUATROP)Universiti Malaysia Terengganu21030 Kuala NerusMalaysia department of Biomaterials Saveetha Dental CollegeSaveetha Institute of Medical and Technical SciencesChennai600077India école Polytechnique d'Abomey-Calavi University of Abomey-Calavi2009CotonouBenin

It is highly desirable to seek green and sustainable technologies,such as employing photo thermal effects to drive energy catalysis processes to address the high energy demand and associated environmental impacts induced by the current *** photothermocatalysis process is an emerging research area with great potential in efficiently converting solar energy through various catalytic ***,achieving simultaneously high conversion efficiency,cyclability,and durability is still a daunting ***,tremendous work is still needed to enhance solar photo thermal catalytic conversion and promote its large-scale *** review developed the principles of coupling solar photon and thermal fields underlying the photothermal effect,exploration of efficient nanocatalysts,development of optofluidic reactor model,and photo thermal synergistic-driven CO_(2) reduction *** ultimate goal was to provide an effective approach that can effectively convert solar energy into photocarriers/hot-electrons and heat,and importantly,can couple them to regulate catalysis reaction pathways toward the production of value-added fuel and chemical energy.

关键词： Photochemistry Photothermal CO_(2)catalytic conversion Nanomaterial Solar fuels and chemicals

A Class of Uncertain Switched Linear Systems’ Pole Assignation

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International Journal of Systems and Control

International Journal of Systems and Control 2007年第3期 206-212页

作者： Yang Yanshuo, zhang Xiaoli department of automation, university of Xiamen, Xiamen, Fujian Province 361005, china

A class of uncertain switched linear systems’ pole assignation based on state feedback is studied. The switched systems not only have unknown time-varying, norm-bounded uncertainty in system’s structure, but also have exogenous disturbance. By using common Lyapunov function method, a switching control strategy to assure each subsystem’s eigenvalue inside a chosen circle on the open left-half complex plane is derived. When every subsystem is unstable, by a designing state feedback controller can make the poles of the systems on the open left-haft complex plane, then the systems are asymptotic stable under the arbitrary switching rules. Thus a sufficient condition of robust stabilization for switched systems is obtained. Based on convex combinations technique and linear matrix inequalities method, the result is expressed in the form of linear matrix inequalities, which can be solved easily. Finally the simulation shows that the designed controller can make the switched systems’ poles inside the chosen circles and make the states asymptotically stable under the arbitrary switching strategy.

关键词： switched systems pole assignment state feedback

Construction and application of formal ontology for mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 577-582页

作者： CHENG Gang 1, 2, zhang Yin-ling1, 2, WANG Fei 1 ,2, zhang Zhen-hui 3, GUO Yu-xiang1, 2 1. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003, china 2. School of Surveying and land Information engineering, Henan Polytechnic university, Jiaozuo 454003, china 3. Qingdao Branch of Naval Aeronautical engineering Institute, Qingdao 266041, china Henan Polytech Univ Key Lab Mine Spatial Informat Technol State Bur Surveying & Mapping Jiaozuo 454003 Peoples R China Henan Polytech Univ Sch Surveying & Land Informat Engn Jiaozuo 454003 Peoples R China Naval Aeronaut Engn Inst Qingdao Branch Qingdao 266041 Peoples R China

Digital mine is the only way for the development of mining industry in china. Due to lack of appropriate standards and norms, and different awareness in the field of digital mine among academia and industry insiders, the meaning for digital mine is still unclear. Starting from the nature of mining and removing of views of specialized fields, this paper constructs formal ontology for digital mine and proposes the four levels for it. The ontology clarifies the concept world for digital mine, defines the meaning of concepts and relations clearly, provides a reference for the standard construction for digital mine and provides a unified semantic framework for the integration of heterogeneous mine data. Meanwhile, it can provide formal reasoning knowledge for expert system of digital mine and improve the intelligence and automation while the machine automatically interpreting and processing mine spatial data.

关键词： Digital mine formalization ontology concept world semantic share

Adaptive Subspace Predictive Control with Time-varying Forgetting Factor

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International Journal of automation and computing 2014年第2期11卷 205-209页

作者： Li zhang Shan-zhi xu Hong-Tao Zhao School of Mechanical Electrical and Information EngineeringShandong University at Weihai Electrical Technology department of Taizhong Group Yuci Hydraulics Industry Co. Ltd Power Generation Plant of Cpi Fushun Thermo Electrical Power Co. Ltd

Aiming at the time-varying characteristics of industrial process, this paper introduces an adaptive subspace predictive control(ASPC) strategy with time-varying forgetting factor based on the original subspace predictive control algorithm(SPC). The new method uses model matching error to calculate the variable forgetting factor, and applies it to constructing Hankel data *** makes the data represent the changes of system information better. For eliminating the steady state error, the derivation of the incremental control is made. Simulation results on a rotary kiln show that this control strategy has achieved a good control effect.

关键词： Subspace predictive control time-varying forgetting factor model matching error adaptive rotary kiln.