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7th Annual IEEE Energy Conversion Congress and Exposition, ECCE 2015

作者： Wang, Cheng Zhang, Kai Liu, Liming Liu, Wenxin State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan Hubei Province430074 China ABB Inc. Raleigh United States Electrical and Computer Engineering Lehigh University BethlehemPA18015 United States

ISBN: (纸本)9781467371506

Modular cascaded multilevel converter is a promising option for high power solar photovoltaic (PV) system due to its modularity, scalability, and distributed maximum power point tracking (MPPT) capability, etc. Nevertheless, inherent mismatch and varied operating conditions (both called module-mismatch) are still the issues to be disclosed. Asymmetrical active power harvesting among individual PV converter modules resulting from module-mismatch will fluctuate dc voltages and polarize the distribution of the alternating terminal voltage and may derivatively cause over-modulation or even destroy the system stability. In this paper, a novel modulation method for cascaded modular multilevel converter with two modes which are low-loss mode for normal operation and extended mode for module-mismatch operation is firstly proposed. With the former mode, the switching times are reduced greatly and then low the switching loss. When it is encountered by module-mismatch, extended mode is able to re-distribute power and then to balance dc-link voltages. Then a reactive power compensation algorithm (RPCA) is analyzed and applied to get a larger operating range based on the proposed modulation method. Finally, a 3MW/12kV system with the proposed modulation and control strategy is developed in Matlab/Simulink platform. Simulation results are presented to demonstrate the effectiveness of the proposed technologies. © 2015 IEEE.

关键词： Modulation

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Body appreciation around the world: Measurement invariance of the Body Appreciation Scale-2 (BAS-2) across 65 nations, 40 languages, gender identities, and age

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Body image 2023年 46卷 449-466页

作者： Viren Swami Ulrich S Tran Stefan Stieger Toivo Aavik Hamed Abdollahpour Ranjbar Sulaiman Olanrewaju Adebayo Reza Afhami Oli Ahmed Annie Aimé Marwan Akel Hussam Al Halbusi George Alexias Khawla F Ali Nursel Alp-Dal Anas B Alsalhani Sara Álvares-Solas Ana Carolina Soares Amaral Sonny Andrianto Trefor Aspden Marios Argyrides John Jamir Benzon R Aruta Stephen Atkin Olusola Ayandele Migle Baceviciene Radvan Bahbouh Andrea Ballesio David Barron Ashleigh Bellard Sóley Sesselja Bender Kerime Derya Beydağ Gorana Birovljević Marie-Ève Blackburn Teresita Borja-Alvarez Joanna Borowiec Miroslava Bozogáňová Solfrid Bratland-Sanda Matthew H E M Browning Anna Brytek-Matera Marina Burakova Yeliz Çakır-Koçak Pablo Camacho Vittorio Emanuele Camilleri Valentina Cazzato Silvia Cerea Apitchaya Chaiwutikornwanich Trawin Chaleeraktrakoon Tim Chambers Qing-Wei Chen Xin Chen Chin-Lung Chien Phatthanakit Chobthamkit Bovornpot Choompunuch Emilio J Compte Jennifer Corrigan Getrude Cosmas Richard G Cowden Kamila Czepczor-Bernat Marcin Czub Wanderson Roberto da Silva Mahboubeh Dadfar Simon E Dalley Lionel Dany Jesus Alfonso D Datu Pedro Henrique Berbert de Carvalho Gabriel Lins de Holanda Coelho Avila Odia S De Jesus Sonia Harzallah Debbabi Sandesh Dhakal Francesca Di Bernardo Donka D Dimitrova Jacinthe Dion Barnaby Dixson Stacey M Donofrio Marius Drysch Hongfei Du Angel M Dzhambov Claire El-Jor Violeta Enea Mehmet Eskin Farinaz Farbod Lorleen Farrugia Leonie Fian Maryanne L Fisher Michał Folwarczny David A Frederick Matthew Fuller-Tyszkiewicz Adrian Furnham Antonio Alías García Shulamit Geller Marta Ghisi Alireza Ghorbani Maria Angeles Gomez Martinez Sarah Gradidge Sylvie Graf Caterina Grano Gyöngyvér Gyene Souheil Hallit Motasem Hamdan Jonathan E Handelzalts Paul H P Hanel Steven R Hawks Issa Hekmati Mai Helmy Tetiana Hill Farah Hina Geraldine Holenweger Martina Hřebíčková Olasupo Augustine Ijabadeniyi Asma Imam Başak İnce Natalia Irrazabal Rasa Jankauskiene Ding-Yu Jiang Micaela Jiménez-Borja Verónica Jiménez-Borja Evan M Johnson Veljko Jov School of Psychology and Sport Science Anglia Ruskin University Cambridge United Kingdom Centre for Psychological Medicine Perdana University Kuala Lumpur Malaysia. Electronic address: viren.swami@aru.ac.uk. Department of Cognition Emotion and Methods in Psychology Faculty of Psychology University of Vienna Vienna Austria. Department of Psychology and Psychodynamics Karl Landsteiner University of Health Sciences Krems an der Donau Austria. Institute of Psychology University of Tartu Tartu Estonia. Department of Psychology Koç University Istanbul Turkiye. Department of Psychology and Behavioural Studies Ekiti State University Ado-Ekiti Nigeria. Department of Art Studies Tarbiat Modares University Tehran Iran. Department of Psychology University of Chittagong Chattogram Bangladesh. Department of Psychoeducation and Psychology Université du Québec en Outaouais Saint-Jérôme Canada. INSPECT-LB: National Institute of Public Health Clinical Epidemiology and Toxicology Beirut Lebanon School of Pharmacy Lebanese International University Beirut Lebanon. Department of Management Ahmed Bin Mohammad Military College Doha Qatar. Faculty of Psychology Panteion University of Social and Political Sciences Athens Greece. Royal College of Surgeons Ireland-Bahrain Adliya Bahrain. Department of Midwifery Faculty of Health Sciences Munzur University Tunceli Turkiya. Department of Oral Medicine and Diagnostic Sciences Vision College of Dentistry and Nursing Vision Colleges Riyadh Saudi Arabia. Facultad de Ciencias de la Vida Universidad Regional Amazónica Ikiam Muyuna Ecuador. Federal Institute of Education Science and Technology of Southeast Minas Gerais Barbacena Brazil. Department of Psychology Universitas Islam Indonesia Yogyakarta Indonesia. Department of Psychology Aberystwyth University Ceredigion United Kingdom. Department of Psychology Neapolis University Pafos Paphos Cyprus. Department of Psychology De La Salle University Phillippines. Department of Gen

The Body Appreciation Scale-2 (BAS-2) is a widely used measure of a core facet of the positive body image construct. However, extant research concerning measurement invariance of the BAS-2 across a large number of nations remains limited. Here, we utilised the Body Image in Nature (BINS) dataset - with data collected between 2020 and 2022 - to assess measurement invariance of the BAS-2 across 65 nations, 40 languages, gender identities, and age groups. Multi-group confirmatory factor analysis indicated that full scalar invariance was upheld across all nations, languages, gender identities, and age groups, suggesting that the unidimensional BAS-2 model has widespread applicability. There were large differences across nations and languages in latent body appreciation, while differences across gender identities and age groups were negligible-to-small. Additionally, greater body appreciation was significantly associated with higher life satisfaction, being single (versus being married or in a committed relationship), and greater rurality (versus urbanicity). Across a subset of nations where nation-level data were available, greater body appreciation was also significantly associated with greater cultural distance from the United states and greater relative income inequality. These findings suggest that the BAS-2 likely captures a near-universal conceptualisation of the body appreciation construct, which should facilitate further cross-cultural research.

关键词： Body appreciation Body appreciation Scale-2 (BAS-2) Cross-cultural Measurement invariance Multi-group confirmatory factor analysis (MG-CFA) Psychometrics Structural analysis

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Evaluation of the calculation method for stray losses in structural parts of HVDC converter transformers

Evaluation of the calculation method for stray losses in str...

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International Conference on Electric Utility Deregulation and Restructuring and Power Technologies (DRPT)

作者： Yaqing Liu Dandan Zhang Zhenbiao Li Qinqing Huang Menghu Li Bin Li Jian Liu State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China

ISBN: (纸本)9781467371070

Stray losses in structural parts are calculated separately during determining load losses of HVDC converter transformers, but the calculation method proposed by IEC 61378-2 standard shows significant difference from the experimental results. The nonlinearity, hysteresis losses, and frequency characteristic are thought as the sources of errors in this paper, and then an electromagnetic-circuit coupling FEM analysis is performed to investigate them. It is shown that the frequency characteristic of the stray losses is the major factor that causes the errors, and the material characteristic should be considered. The magnetic and nonmagnetic materials are suggested to be calculated separately.

关键词： Magnetic hysteresis Decision support systems IEC Standards Finite element analysis Analytical models Power industry HVDC transmission

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Reconstruction of the COMPSS-D ECRH Systems on the J-TEXT Tokamak

Reconstruction of the COMPSS-D ECRH Systems on the J-TEXT To...

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IEEE Symposium on Fusion engineering

作者： D. H. Xia C. H. Liu Z. J. Wang M. Zhang W. Zheng L. Q. Jiang D. L. Sun Z. Zeng F. T. Cui Z. X. Yu G. Zhuang K. X. Yu Y. Pan State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China

As a flexible and controllable auxiliary heating method, electron cyclotron resonance heating and current drive has been widely used in various plasma confinement devices and also will be used on J-TEXT. The main parts of the J-TEXT electron cyclotron systems under development are donated by the Culham Science Center, including six 60 GHz/200 kW/5 s (0.5 s) gyrotrons, six magnets and auxiliary power supplies for the gyrtrons, transmission parts, etc. For these systems, the output mode of the gyrotron is TE_(02) mode and converted to TE_(01) mode for low loss transmission. Then the HE11 mode for efficient coupling is obtained at the end of the transmission lines by a TE_(01) - TE_(11) - HE_(11) mode conversion sequence. A 100kV/60A pulse step modulation power supply has been developed to feed all the six gyrotrons. The control system based on the Compact Reconfigurable I/O - 9068 platform of National Instruments for monitoring, timing and protection is being designed. Other units such as the cooling loops, a new quasi-optical launcher and a spared auxiliary power supply are on the way. It is hoped that four to six EC subsystems can be finally used on the J-TEXT tokamak, and the first one is scheduled to be completed at the end of 2015.

关键词： J-TEXT tokamak ECRH rebuilding

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The risk-based assessment of static voltage stability issues with consideration of load and wind power uncertainties

The risk-based assessment of static voltage stability issues...

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Clemson University Power Systems Conference (PSC)

作者： Weisi Deng Buhan Zhang Hongfa Ding State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China

ISBN: (纸本)9781479919529

The risk-based assessment is a new approach to the voltage stability assessment in power system. Under several uncertainties, the security risk of static voltage stability with considerable of wind power can be evaluated. In this paper, the Quasi-Monte Carlo (QMC) simulation is used to speed up Monte Carlo by improving the technical of sample generation. Besides, a new voltage stability index is defined, which reveal critical characteristics of static voltage stability. The local voltage stability margin (LVSM) considering the security risk at a forecasted operating point can be calculated to evaluate the voltage stability. Testing on a modified IEEE New England 39-bus system, results from the proposed method are compared agains the result from the conventional method. The proposed method's effectiveness and advantaged are demonstrated with the test results.

关键词： Power system stability Stability criteria Circuit stability Wind power generation Uncertainty Load flow

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Comparison of stator DC-excited vernier reluctance machines with synchronous reluctance machines

Comparison of stator DC-excited vernier reluctance machines ...

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IEEE International Conference on Electric Machines and Drives (IEMDC)

作者： Shaofeng Jia Ronghai Qu Jian Li Yu Chen State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China

Stator DC-excited vernier reluctance machines (DC-VRMs) are vernier reluctance machines equiped with additional DC field winding in stator to generate the exciting field, a rotating field similar to synchronous reluctance machines (SynRMs). This paper compares the electromagnetic performance of two non-PM reluctacne machines including DC-VRMs and SynRMs. First, the basic operation principle of DC-VRMs and SynRMs are briefly reviewed. Then, four machine models, two DC-VRMs and two SynRMs are designed and optimized for comparison. For a fair comparison, the phase current, current density, slot fill factor and dimensions including the stator outer diameter, air gap and stack length are designed the same. The electromagnetic performance including flux density, torque quality, overload capacity, power factor and losses are compared in detail.

关键词： Windings Torque Stator windings Harmonic analysis Rotors Reluctance machines

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Optimal design of a direct-driven permanent magnet synchronous wind generator

Optimal design of a direct-driven permanent magnet synchrono...

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IEEE International Conference on Industrial technology (ICIT)

作者： Pedram Asef Tianjie Zou Haiyang Fang State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China

Low-speed high-torque direct-drive permanent magnet (LSHTPM) synchronous machines, which are characterized by large dimensions and weight, have huge potential for wind power generation. Despite to this fact, before the manufacture process of these machines, optimal design should be done to reduce the material costs and maximize power density and efficiency. In this paper, t he attention is focused on an optimal design of a 1.5MW direct-drive wind generator which is done in this research. The relationships between main dimensions of the machine and its power density, efficiency are investigated. In addition, a novel analytical optimization method is used to find optimal aspect ratio and split ratio to maximize power density and efficiency. The influences of electrical and magnetic load on the optimal aspect ratio and split ratio are also explored. Other parameters and results that may have major influence on the main dimensions such as pole number, slot width, and etc. are carried out and also discussed.

关键词： Current density Generators Density measurement Power system measurements Stator windings Stress

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Two-Photon Fluorescence Properties and Ultrafast Responses of a Hyperbranched Diketo-Pyrrolo-Pyrrole Polymer with Triphenylamine as the Core

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Chinese Physics Letters 2015年第4期32卷 139-143页

作者：王耀川姜义华王桂秋刘大军李波花建丽 Department of Physics Dalian Maritime University Dalian 110626 State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116024 Lab for Advanced Materials Department of Chemistry East China University of Science and Technology Shanghai 200237 Department of Electronic Engineering East China Normal University Shanghai 200241

The two-photon fluorescence properties and ultrafast responses of a hyperbranched polyyne （hb-DPP-J2） with triphenylamine as the central core, Diketo-Pyrrolo-Pyrrole as the connecting unit and electron acceptor are studied. The polymer has a D-π-A-π-D conjugated structure along the extended polyyne w-bridge systems, and the effective condugated unit repeats itself in the whole hyperbranehed polymer chain. The polymer exhibits a large two-photon absorption cross section and high fluorescence quantum yields. The ultrafast dynamic results give a deep understanding of the excited energy transfer processes under excitation, and reveal a long relaxation lifetime of the intramolecular charge transfer （ICT） state.

关键词： DPP Two-Photon Fluorescence Properties and Ultrafast Responses of a Hyperbranched Diketo-Pyrrolo-Pyrrole Polymer with Triphenylamine as the Core THF ICT TPA

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Short-term Frequency Support of Power System From Wind Farms Using Energy Storage System

Short-term Frequency Support of Power System From Wind Farms...

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IEEE Power and Energy Society General Meeting

作者： Ju Liu Wei Yao Jinyu Wen Yao Long State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China

ISBN: (纸本)9781467380416

The high penetration of non-dispatch-able, grid-connected wind power is bringing serious challenge to the frequency regulation of power systems because of the decoupling between the output power of doubly-fed induction generator-based wind farms and the grid frequency. Therefore, this paper proposes a compensation strategy to help wind farms to support the system frequency response by using the energy storage system. Firstly, the conclusion that the wind farm, which is equipped an energy storage system with 5% rated power of wind farm, could have similar short-term frequency response ability as synchronous generators with the same capacity is deduced. Then, a fuzzy logic controller is designed for the energy storage system to achieve this. Simulation results of a simplified practical power system show that wind farms with the proposed compensation strategy could response to the frequency change of power system rapidly and support the short-term frequency regulation effectively under various disturbances.

关键词： Energy storage Frequency regulation Fuzzy logic control Wind farms Short-term frequency support

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Improved discretization-based decoupled feedback control for series connected converter of SCC

Improved discretization-based decoupled feedback control for...

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International Conference on Applied Superconductivity and electromagnetic Devices, ASEMD

作者： Jing Shi Kang Gong Yang Liu Xiao Zhou Yue Jin Tang Li Ren Jing Dong Li State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology Wuhan China

ISBN: (纸本)9781467381086

The active superconducting current controller (SCC) adopts the principle of series voltage compensation, which can be utilized to limit the fault current effectively during fault conditions. This paper presents an improved discretization-based decoupled feedback control for series connected converter of SCC. To improve the system dynamics of discretization-based decoupled feedback control, the effect of the control time delay is considered. Furthermore, a linear state feedback loop which considering the output error vectors is added to the control system to achieve the feature of deadbeat. MATlab simulation is performed to evaluate the performance of the proposed control.

关键词： Feedback control Mathematical model Delay effects Superconductivity Voltage control state feedback

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