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Fast filtering algorithm based on vibration systems and neural information exchange and its application to micro motion robot

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Chinese Physics B 2014年第1期23卷 159-169页

作者：高娃查富生宋宝玉李满天 State Key Laboratory of Robotics and system Harbin Institute of Technology department of Mechanical Design Harbin Institute of Technology

This paper develops a fast filtering algorithm based on vibration systems theory and neural information exchange approach. The characters, including the derivation process and parameter analysis, are discussed and the feasibility and the effectiveness are testified by the filtering performance compared with various filtering methods, such as the fast wavelet transform algorithm, the particle filtering method and our previously developed single degree of freedom vibration system filtering algorithm, according to simulation and practical approaches. Meanwhile, the comparisons indicate that a significant advantage of the proposed fast filtering algorithm is its extremely fast filtering speed with good filtering perfi^rmance. Further, the developed fast filtering algorithm is applied to the navigation and positioning system of the micro motion robot, which is a high real-time requirement for the signals preprocessing. Then, the preprocessing data is used to estimate the heading angle error and the attitude angle error of the micro motion robot. The estimation experiments illustrate the high practicality of the proposed fast filtering algorithm.

关键词： fast filtering vibration system neural information exchange micro motion robot

Transient stability and emergency control

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Science China(Technological Sciences) 2009年第2期52卷 420-428页

作者： ZHANG XueMin MEI ShengWei WU ShengYu State Key Lab of power system Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

Comparability of emergency control strategies with different instability modes is the key issue to decide which control strategy to be implemented. This paper considers that the essential factor causing instability should be used to form a unified standard to assess the effectiveness of control strategies with different instability modes. Thus a switching control stabilization principle was proposed based on elimination of the unbalanced energy between mechanical and electrical energies of generator sets. Along this way, the difficulty of seeking a Lyapunov function was circumvented. According to the principle, an emergency control algorithm framework was established to handle transient stability assessment, control location selection and control amount evaluation. Within the framework, this paper studied instability mode transition, then proposed an algorithm based on prediction function and a new approach to normalized stability margin stemmed from static EEAC method, which can increase comparability of various control locations. The simulations on the New-England system verified the proposed emergency control method for stabilizing transient stability.

关键词： emergency control switching system unbalanced energy

Chaos Control in Electromechanical Seismograph system with Noise Disturbances

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Journal of Donghua University(English Edition) 2012年第3期29卷 203-208页

作者：郑连清申滔陆治国 State Key Laboratory of power Transmission Equipment&system Security and New technology Chongqing University

In order to eliminate chaotic oscillation of electromechanical characteristics of seismograph system, the complex dynamic the four-dimensional nonlinear equations of seismograph system were analyzed. Sliding mode method was applied to stabilize the chaotic orbits of the eleetromechanieal seismograph system to arbitrary chosen fixed points and periodic orbits precisely, and MATLAB simulations were presented to confirm the validity of the controller. The results show that using sliding mode method can make the system track target orbit strictly and smoothly with short transition time, and its insensitivity to noise disturbances is shown. It also provides reference for relevant chaos control in relevant system.

关键词： electromechanical seismograph system chaotic attractor slidine mode: uncertain parameter: noise disturbance simulation

Autonomous Optimal Coordination Scheme in Protection system of power Distribution Network by Using Multi-Agent Concept

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Transactions of Tianjin University 2008年第2期14卷 106-111页

作者： LEE Seung-Jae KIM Tae-Wan LEE Gi-Young Next-Generation power system technology Center Myongji UniversityYongin449-728KyunggidoKorea

A protection system using a multi-agent concept for power distribution networks is *** digital over current relay(OCR)is developed as an agent by adding its own intelligence,self-tuning and communication *** main advantage of the multi-agent concept is that a group of agents work together to achieve a global goal which is beyond the ability of each individual *** order to cope with frequent changes in the network operation condition and faults,an OCR agent,proposed in this paper,is able to detect a fault or a change in the network and find its optimal parameters for protection in an autonomous manner considering information of the whole network obtained by communication between other *** this kind of coordination and information exchanges,not only a local but also a global protective scheme is *** in a simple distribution network show the effectiveness of the proposed protection system.

关键词： multi-agent system over current relay(OCR) communication protection of distribution network

ADMM-based Distributed Algorithm for Economic Dispatch in power systems With Both Packet Drops and Communication Delays

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IEEE/CAA Journal of Automatica Sinica 2020年第3期7卷 842-852页

作者： Qing Yang Gang Chen Ting Wang State Key Laboratory of power Transmission Equipment and system Security and New technology and the School of AutomationChongqing UniversityChongqing 400044China IEEE

By virtue of alternating direction method of multipliers(ADMM), Newton-Raphson method, ratio consensus approach and running sum method, two distributed iterative strategies are presented in this paper to address the economic dispatch problem(EDP) in power systems. Different from most of the existing distributed ED approaches which neglect the effects of packet drops or/and time delays, this paper takes into account both packet drops and time delays which frequently occur in communication networks. Moreover, directed and possibly unbalanced graphs are considered in our algorithms, over which many distributed approaches fail to converge. Furthermore, the proposed schemes can address the EDP with local constraints of generators and nonquadratic convex cost functions, not just quadratic ones required in some existing ED approaches. Both theoretical analyses and simulation studies are provided to demonstrate the effectiveness of the proposed schemes.

关键词： Alternating direction method of multipliers(ADMM) average consensus directed graph(digraph) distributed algorithm economic dispatch packet drops time delays

Robust Voltage Control Considering Uncertainties of Renewable Energies and Loads via Improved Generative Adversarial Network

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Journal of Modern power systems and Clean Energy 2020年第6期8卷 1104-1114页

作者： Qianyu Zhao Wenlong Liao Shouxiang Wang Jayakrishnan Radhakrishna Pillai the Key Laboratory of Smart Grid of Ministry of Education and Tianjin Key Laboratory of power system Simulation and Control Tianjin UniversityTianjinChina the department of Energy technology Aalborg UniversityAalborgDenmark

The fluctuation of output power of renewable energies and loads brings challenges to the scheduling and operation of the distribution *** this paper,a robust voltage control model is proposed to cope with the uncertainties of renewable energies and loads based on an improved generative adversarial network(IGAN).Firstly,both real and predicted data are used to train the IGAN consisting of a discriminator and a *** noises sampled from the Gaussian distribution are fed to the generator to generate a large number of scenarios that are utilized for robust voltage control after scenario ***,a new improved wolf pack algorithm(IWPA)is presented to solve the formulated robust voltage control model,since the accuracy of the solutions obtained by traditional methods is *** simulation results show that the IGAN can accurately capture the probability distribution characteristics and dynamic nonlinear characteristics of renewable energies and loads,which makes the scenarios generated by IGAN more suitable for robust voltage control than those generated by traditional ***,IWPA has a better performance than traditional methods in terms of convergence speed,accuracy,and stability for robust voltage control.

关键词： Robust voltage control uncertainty generative adversarial network wolf pack algorithm

Analysis on discharge process of a plasma-jet triggered gas spark switch

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Plasma Science and technology 2018年第1期20卷 59-66页

作者：铁维昊孟萃张雨婷闫自让张乔根 department of Engineering Physics Tsinghua University Xi'an Electronic Engineering Research Institute Aviation Key Laboratory of Science and technology on Aerospace power system School of Electrical Engineering Xi'an Jiaotong University

The plasma-jet triggered gas switch （PJTGS） could operate at a low working coefficient with a low jitter. We observed and analyzed the discharge process of the PJTGS at the lowest working coefficient of 47% with the trigger voltage of 40 kV and the pulse energy of 2 J to evaluate the effect of the plasma jet. The temporal and spatial evolution and the optical emission speclrum of the plasma jet were captured. And the spraying delay time and outlet velocity under different gas pressures were investigated. In addition, the particle in cell with Monte Carlo collision was employed to obtain the particle distribution of the plasma jet varying with time. The results show that, the plasma jet generated by spark discharge is sprayed into a spark gap within tens of nanoseconds, and its outlet velocity could reach 104 m s-1. The plasma jet plays a non-penetrating inducing role in the triggered discharge process of the PJTGS. On the one hand, the plasma jet provides the initial electrons needed by the discharge; on the other hand, a large number of electrons focusing on the head of the plasma jet distort the electric field between the head of the plasma jet and the opposite electrode. Therefore, a fast discharge originated from the plasma jet is induced and quickly bridges two electrodes.

关键词： spark gap plasma jet triggered discharge

Optimizing near-carbon-free nuclear energy systems:advances in reactor operation digital twin through hybrid machine learning algorithms for parameter identification and state estimation

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Nuclear Science and Techniques 2024年第8期35卷 177-203页

作者： Li‑Zhan Hong He‑Lin Gong Hong‑Jun Ji Jia‑Liang Lu Han Li Qing Li Paris Elite Institute of technology Shanghai Jiao Tong UniversityShanghai 200240China Science and technology on Reactor system Design technology Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy *** previous studies,we developed a reactor operation digital twin(RODT).However,non-differentiabilities and discontinuities arise when employing machine learning-based surrogate forward models,challenging traditional gradient-based inverse methods and their *** study investigated deterministic and metaheuristic algorithms and developed hybrid algorithms to address these *** efficient modular RODT software framework that incorporates these methods into its post-evaluation module is presented for comprehensive *** methods were rigorously assessed based on convergence profiles,stability with respect to noise,and computational *** numerical results show that the hybrid KNNLHS algorithm excels in real-time online applications,balancing accuracy and efficiency with a prediction error rate of only 1%and processing times of less than 0.1 ***,algorithms such as FSA,DE,and ADE,although slightly slower(approximately 1 s),demonstrated higher accuracy with a 0.3%relative L_2 error,which advances RODT methodologies to harness machine learning and system modeling for improved reactor monitoring,systematic diagnosis of off-normal events,and lifetime management *** developed modular software and novel optimization methods presented offer pathways to realize the full potential of RODT for transforming energy engineering practices.

关键词： Parameter identification State estimation Reactor operation digital twin Reduced order model Inverse problem

Research on active arc-ignition technology as a possible residual-energy-release strategy in electromagnetic rail launch

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Plasma Science and technology 2021年第8期23卷 167-174页

作者： Xiyuan CAI Sai TAN Junyong LU Xiao ZHANG Yun GUO National Key Laboratory of Science and technology on Vessel Integrated power system Naval University of EngineeringWuhan 430033People's Republic of China

In order to solve the problem of the original residual energy release strategy being unsuitable for high-energy and fast-firing electromagnetic rail launch,this work has explored the applicability of active arc-ignition technology(AAT).The results obtained from the comparison of launching experiments show that AAT has no influence on the acceleration of the armature and is capable of quickly releasing the residual *** on the theory of magnetohydrodynamics,this work has also made numerical simulation of the muzzle arc,analyzed the influence of AAT on the muzzle arc flow field,electromagnetic(EM)field and temperature field,and evaluated the performance of AAT according to the projectile initial disturbance,the EM impact on guidance devices and the rail *** results show that AAT is now one of the most practicable strategies for residual energy release.

关键词： muzzle arc initial disturbance guidance device arc ablation backflow