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arXiv 2025年

作者： Tondji, Lionel Lorenz, Dirk A. Necoara, Ion Institute of Analysis and Algebra TU Braunschweig Braunschweig38092 Germany Automatic Control and Systems Engineering Department University Politehnica Bucharest Bucharest060042 Romania Gheorghe Mihoc-Caius Iacob Institute of Mathematical Statistics and Applied Mathematics The Romanian Academy Bucharest050711 Romania

In this paper, we propose a randomized accelerated method for the minimization of a strongly convex function under linear constraints. The method is of Kaczmarz-type, i.e. it only uses a single linear equation in each iteration. To obtain acceleration we build on the fact that the Kaczmarz method is dual to a coordinate descent method. We use a recently proposed acceleration method for the randomized coordinate descent and transfer it to the primal space. This method inherits many of the attractive features of the accelerated coordinate descent method, including its worst-case convergence rates. A theoretical analysis of the convergence of the proposed method is given. Numerical experiments show that the proposed method is more efficient and faster than the existing methods for solving the same *** Codes 65F10, 68W20, 90C25 © 2025, CC BY.

关键词： Convex optimization

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Real-time Pricing Mechanism for V2G Using Distributed Bilevel Optimization

Real-time Pricing Mechanism for V2G Using Distributed Bileve...

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IEEE Conference on Decision and control

作者： Jiawei You Xinliang Dai Yuning Jiang Haoyu Yin Yuanming Shi Colin N. Jones School of Information Science and Technology ShanghaiTech University China EPFL Institute for Automation and Applied Informatics Karlsruhe Institute of Technology Germany Automatic Control Laboratory EPFL Switzerland Department of Electrical and Systems Engineering Washington University in St. Louis USA

ISBN: (数字)9798350316339

ISBN: (纸本)9798350316346

This paper explores the impact of the burgeoning electric vehicle (EV) presence on distribution grid operations, highlighting the challenges they present to conventional pricing strategies due to their dual role as power consumers and suppliers, coupled with their energy storage capabilities. We propose an advanced real-time pricing model for the electricity market, employing a novel distributed bilevel optimization framework. This framework distinguishes between the distribution system operator (DSO) at the upper level and the EVs at the lower level, each aiming to optimize profit margins. The optimization includes power flow constraints at the upper level to ensure efficient operation within safe system limits, while model predictive control (MPC) is used to optimize lower-level EV responses. Additionally, we provide a rigorous convergence analysis of the proposed bilevel optimization method. Detailed convergence studies and simulation results demonstrate the effectiveness and superiority of the proposed algorithm.

关键词： Vehicle-to-grid Simulation Pricing Prediction algorithms Real-time systems Robustness Convergence Load flow Energy storage Predictive control

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Fractional-Order control of a Wind Turbine Using Manta Ray Foraging Optimization

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Computers, Materials & Continua 2021年第7期68卷 185-199页

作者： Hegazy Rezk Mohammed Mazen Alhato Mohemmed Alhaider Soufiene Bouallègue College of Engineering at Wadi Addawaser Prince Sattam Bin Abdulaziz UniversityAl-Kharj11911Saudi Arabia Department of Electrical Engineering Faculty of EngineeringMinia University61517MiniaEgypt Research Laboratory in Automatic Control(LARA) National Engineering School of Tunis(ENIT)University of TunisTunis1002Tunisia High Institute of Industrial Systems of Gabès University of GabèsGabès6011Tunisia

In this research paper,an improved strategy to enhance the performance of the DC-link voltage loop regulation in a Doubly Fed Induction Generator(DFIG)based wind energy system has been *** proposed strategy used the robust Fractional-Order(FO)Proportional-Integral(PI)control *** FOPI control contains a non-integer order which is preferred over the integer-order control owing to its *** offers extra flexibility in design and demonstrates superior outcomes such as high robustness and *** optimal gains of the FOPI controller have been determined using a recent Manta Ray Foraging Optimization(MRFO)*** the optimization process,the FOPI controller’s parameters are assigned to be the decision variables whereas the objective function is the error racking that to be *** prove the superiority of the MRFO algorithm,an empirical comparison study with the homologous particle swarm optimization and genetic algorithm is *** obtained results proved the superiority of the introduced strategy in tracking and control performances against various conditions such as voltage dips and wind speed variation.

关键词： Renewable energy modeling wind turbine doubly fed induction generator fractional order control manta ray foraging optimization

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Identification of Thermal Failure Profiles in Stator Winding Insulation by Impedance Spectroscopy

Identification of Thermal Failure Profiles in Stator Winding...

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International Conference on Electrical Machines, ICEM

作者： Edward J. W. Stone Panagiotis A. Panagiotou Johannes Mühlthaler Andrew R. Mills Alexis Lambourne Geraint W. Jewell Department of Electronic and Electrical Engineering The University of Sheffield Sheffield UK Rolls-Royce Electrical Rolls-Royce Deutschland Ltd & Co KG Munich Germany Department of Automatic Control and Systems Engineering The University of Sheffield Sheffield UK Rolls-Royce Central Services Rolls-Royce Plc. UK Derby UK

ISBN: (数字)9798350370607

ISBN: (纸本)9798350370614

This paper presents a novel application of impedance spectroscopy as a means of inspection for stator winding insulation. It proposes, for the first time, a means for health monitoring and failure identification during thermal degradation effects in the insulation systems of stator coils from a concentrated stator winding. By periodical ex-situ inspection of these coils, the thermal ageing data of the insulation are profiled up to the point of failure. The study maps this evolution of thermal degradation patterns via novel interpretation of the impedance frequency responses, using well known techniques such as the Bode and Nyquist plots. This grants further insight into the characteristics shown in the ageing profiles over time and frequency. These new profiles enable the identification of critical points that can act as pre-emptive indicators of coil health and failure inception. This is a key finding as it renders the capability to provide an adequate lifing tool for electrical machine windings and coil assemblies within industrial settings. The insulation system examined in this study is taken from the coils of a concentrated stator winding in a 2MW permanent magnet generator used in an aerospace application.

关键词： Coils Degradation Insulation Spectroscopy Time-frequency analysis Stator windings Inspection Aging Impedance Thermal degradation

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Data-driven Model Based Online Fault Detection Using OMP-ERR 4

Data-driven Model Based Online Fault Detection Using OMP-ERR

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4th International Conference on Industrial Artificial Intelligence, IAI 2022

作者： Zhou, Guangze Luo, Zhong Zhu, Yunpeng Gao, Yi Wang, Zhiao Northeastern University School of Mechanical Engineering and Automation Shenyang110819 China Northeastern University Key Laboratory of Vibration and Control of Aero-Propulsion Systems Ministry of Education of China Shenyang110819 China Dalian University of Technology State Key Laboratory of Structural Analysis for Industrial Equipment Dalian116024 China University of Sheffield Department of Automatic Control and System Engineering SheffieldS13JD United Kingdom

ISBN: (数字)9781665451208

ISBN: (纸本)9781665451208

Model based online fault detection often conducted by extracting features from models driven by system input and output data under various working conditions. The efficiency of online system modelling is therefore significant to improve the performance of online fault detections. In this study, a novel fast data-driven modelling approach, known as the OMP (Orthogonal Matching Pursuit)- ERR (Error Reduction Ratio) method is proposed to improve the efficiency of online fault detections. The new system identification method is motivated by noticing that the traditional OMP algorithm is much faster but usually less accurate than the OLS (Orthogonal least squares) algorithm in the identification of system NARX (Nonlinear Auto-Regressive with Exogenous inputs) models. The problem is first illustrated by the identification of a Single Degree of Freedom (SDoF) system. After that, the OMP-ERR algorithm is developed to improve the NARX modelling efficiency for the purpose of system model-based online fault detections. A case study on the crack detection of a cantilever beam shows that the new approach is over 10 times faster than the traditional OLS modelling process, demonstrating the promising applications of the new approach in online fault detections in engineering practice. © 2022 IEEE.

关键词： Least squares approximations

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Modelling of Insulation in Concentrated Stator Coils for Characterisation and Material Changes

Modelling of Insulation in Concentrated Stator Coils for Cha...

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International Conference on Electrical Machines, ICEM

ISBN: (数字)9798350370607

ISBN: (纸本)9798350370614

The highly demanding operation of electrical machines in aerospace can lead to the degradation of electrical insulation systems within the machine windings over time. This paper presents a novel method for high frequency modelling of a coil from the concentrated stator winding of an 2MW aerospace generator, for the purpose of characterising the insulation system by the amplitude and phase responses by the Bode plots in the same framework as electrical impedance spectroscopy. This new approach of high frequency model utilises a finite element model, deployed in tandem with an electrical equivalent circuit representation. Matlab is used to quantify the results taken from finite element modelling and implemented into LTSpice, so that the model considers mutual coupling of inductances and high-frequency effects, such as proximity and skin effects. This novel methodology allows extraction of the impedance profile with respect to the material changes within the simulated insulation system.

关键词： Coils Insulation Spectroscopy Stator windings Mathematical models Finite element analysis Impedance High frequency Integrated circuit modeling Skin effect

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On the conceptualization of total disturbance and its profound implications

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Science China(Information Sciences) 2020年第2期63卷 221-223页

作者： Sen CHEN Wenyan BAI Yu HU Yi HUANG Zhiqiang GAO Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences Beijing Aerospace Automatic Control Institute Center for Advanced Control Technologies Department of Electrical Engineering and Computer ScienceCleveland State University

Dear editor,How to deal with uncertainties and/or disturbances is a central issue pushing the development of both control science and control technology. Among various approaches, the active disturbance rejection control (ADRC) has been successfully implemented in various industrial practices because of its uniqueness in concepts, simplicity

关键词： ESO On the conceptualization of total disturbance and its profound implications

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Electromechanical System Of control And Determination Of Strength Of Concrete By Non-Destructive Method

Electromechanical System Of Control And Determination Of Str...

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Advanced Technology (KhPIWeek), IEEE KhPI Week on

作者： Lidiya Parashchuk Yurii Shelekh Myroslav Sabat Lubomyra Odosii Deartment of electromechnical and electronics Hetman Petro Sahaidachnyi National Army Academy Lviv Ukraine Department of Electric Power Engineering and Control Systems Lviv Polytechnic National University Lviv Ukraine

The current trend in the development of non-destructive testing of materials in the building industry is mainly concerned with the detection of flaws and defects in concrete elements and structures, and acoustic methods are prospects in this field. An important indicator of the quality of concrete is strength. However, non-destructive testing methods do not allow direct linking of the electrical characteristics with the strength. In this paper, in the form of a graphical dependence using an electromechanical installation based on experimental studies, the relationship between strength and acoustic impedance is shown.

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Dynamics Analysis of Active Variable Stiffness Vibration Isolator for Whole-Spacecraft systems Based on Nonlinear Output Frequency Response Functions

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Acta Mechanica Solida Sinica 2020年第6期33卷 731-743页

作者： Kefan Xu Yewei Zhang Yunpeng Zhu Jian Zang Liqun Chen College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Department of Automatic Control and Systems Engineering Sheffield UniversityMapping StreetSheffield SI 3JDUK Harbin Institute of Technology Shenzhen 518055China

In order to improve the harsh dynamic environment experienced by heavy rockets during different external excitations,this study presents a novel active variable stiffness vibration isolator(AVS-VI)used as the vibration isolation device to reduce excessive vibration of the whole-spacecraft isolation *** AVS-VI is composed of horizontal stiffness spring,positive stiffness spring,parallelogram linkage mechanism,piezoelectric actuator,acceleration sensor,viscoelastic damping,and PID active *** on the AVS-VI,the generalized vibration transmissibility determined by the nonlinear output frequency response functions and the energy absorption rate is applied to analyze the isolation performance of the whole-spacecraft system with *** AVS-VI can conduct adaptive vibration suppression with variable stiffness to the whole-spacecraft system,and the analysis results indicate that the AVS-VI is efTective in reducing the extravagant vibration of the whole-spacecraft system,where the vibration isolation is decreased up to above 65%under different acceleration ***,different parameters of AVS-VI are considered to optimize the whole-spacecraft system based on the generalized vibration transmissibility and the energy absorption rate.

关键词： Vibration isolation Active variable stiffness vibration isolator Nonlinear output frequency response functions(NOFRFs) Transmissibility

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An Adaptive CUSUM Approach for Automating Sleep Apnoea Analysis Based on Pulse and Oximetry Data

An Adaptive CUSUM Approach for Automating Sleep Apnoea Analy...

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IEEE International Conference on Mechatronics and Automation

作者： Dongjin Yang Eishaan Bhargava Heather Elphick Lyudmila S. Mihaylova Dept. of Automatic Control and Systems Engineering University of Sheffield UK Department of Paediatric Otolaryngology Sheffield Children’s Hospital Sheffield UK Department of Paediatric Respiratory and Sleep Medicine Sheffield Children’s Hospital Sheffield UK

Sleep apnoea is a common sleep disorder during human sleep. It is usually diagnosed by a doctor after recording one nights’ sleep signals. Patients have to go to the hospital to record sleep signals, which is time-consuming and resource-intensive. The study focused on two signals, pulse data and oximetry data, with the aim of detecting apnoea using a single signal. This paper introduced an anomaly detection approach using the adaptive cumulative sum (ACUSUM) change point detection algorithm to monitor outliers in the signal. In addition, the test results of ACUSUM will be compared with the test results of classical CUSUM. Besides, the threshold selection has been changed from an unchanging constant to a value related to the standard deviation of the selected signal based on a rational subgroup process. The results of the comparison confirm that ACUSUM is better than classical CUSUM in the accuracy of automatic detection.

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