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Traceability Method of Measuring System for Arbitrary High-Voltage and High-Current Impulses

IEEE Sensors Journal 2025年

作者： Yang, Ning Liu, Yi Lin, Mingxing Li, Liuxia Lin, Fuchang Long, Zhaozhi Diao, Yinglong Li, Wenting Fan, Jiawei Huazhong University of Science and Technology State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Wuhan430074 China Huazhong University of Science and Technology Key Laboratory of Pulse Power Technology Ministry of Education School of Electrical and Electronic Engineering Wuhan430074 China State Grid Sichuan Electric Power Company Chengdu610041 China China Electric Power Research Institute 430072 China

High-voltage and high-current impulse waveforms, characterized by a diverse frequency spectrum, pose challenges for accurate traceability to national standards. Traditional methods for tracing impulse quantities to a single-frequency measurement standard are not universally applicable. This paper introduces a novel approach that establishes a general traceability method by mapping the impulse scale factor to a multi-frequency AC scale factor based on the energy spectrum, enabling indirect traceability to the power frequency standard under high-voltage or high-current conditions. A full-waveform inversion method is employed that integrates the frequency spectrum of measured impulse waveforms using fast Fourier transform (FFT) with the frequency response characteristics of the measuring system, which are determined through convolution based on square wave responses. This approach facilitates traceability of time parameters for arbitrary impulse waveforms. Experimental results demonstrate that the resistive impulse voltage divider's scale factor uncertainties at low and high voltages are 3.100×10-4 and 1.344×10-3, respectively. Additionally, the uncertainties for the T1 and T2 parameters of the inverted waveform of the attenuator are within 0.45% and 0.03%, respectively. These findings validate the effectiveness of our traceability theory. © 2001-2012 IEEE.

关键词： Electric frequency measurement

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Design of the high voltage isolation transmission module with low delay for ECRH system on J-TEXT

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Plasma Science and technology 2018年第2期20卷 19-25页

作者：马海燕夏冬辉王之江崔芳泰余振雄金易坤刘昌海 State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology

As a flexible auxiliary heating method,the electron cyclotron resonance heating（ECRH） has been widely used in many tokamaks and also will be applied for the J-TEXT *** meet requirements of protection and fault analysis for the ECRH system on J-TEXT,signals of gyrotrons such as the cathode voltage and current,the anode voltage and current,etc should be transmitted to the control and data acquisition *** the high voltage environment of gyrotrons,isolation transmission module based on FPGA and optical fiber communication has been designed and *** test results indicate that the designed module has strong anti-noise ability,low error rate and high transmission *** delay of the module is no more than 5 μs which can fulfill the requirements.

关键词： J-TEXT tokamak electron cyclotron resonance heating high-voltage isolation

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Equilibrium Reconstruction and Integration of EFIT with Diagnoses in J-TEXT Tokamak

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Plasma Science and technology 2016年第12期18卷 1225-1230页

作者：高海龙徐涛张帆简翔张晓卿杨州军高丽江中和庄革 State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology

The EFIT program is integrated with the high resolution laser polarimeter interferometer system（POLARIS）, the soft X-ray imaging diagnostic system（SXR） and the electron cyclotron emission radiometer（ECE） in the J-TEXT tokamak. Then some internal information about Faraday angle and the position of safety factor q=1 can be obtained as a constraint to EFIT. The modified EFIT code is used to calculate the internal parameters such as flux function, safety factor q, pressure and current density.

关键词： EFIT equilibrium reconstruction diagnoses

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Mode-Coupling Analysis of Parametric Decay Instability in Magnetized Plasmas

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Plasma Science and technology 2014年第9期16卷 809-814页

作者：袁媛江中和郭伟欣孙新锋胡希伟 State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology

In this paper, derived from Maxwell and fluid equations of plasmas, unified nonlinear wave equations are used to describe the parametric decay instability （PDI） in magnetized plasmas, and in view of mode-coupling, we can obtain all the possible PDI channels. By solving the nonlinear equations with a mode-coupling method, we obtain the growth rate of the PDI, of which all of the three waves are ordinary mode （O-mode） or extraordinary mode （X-mode） wave. Under the dipole approximation, an explicit formula of the growth rate of the X-mode and the condition of the equilibrium density scale are obtained. According to the existence conditions of three X-mode waves, this kind of instability might exist in ECRH with the second harmonic X-mode wave.

关键词： magnetized plasma parametric decay instability mode-coupling theory,growth rate

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Power dependence of density limit due to plasma-wall interaction in a burning plasma

arXiv

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arXiv 2025年

作者： Liu, Jiaxing Zhu, Ping Escande, Dominique Franck State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan430074 China Department of Nuclear Engineering and Engineering Physics University of Wisconsin-Madison MadisonWI53706 United States Aix-Marseille Université CNRS PIIM UMR 7345 Marseille France

The density limit is one of the major obstacles to achieving the desired fusion performance in tokamaks. However, the underlying physics mechanism for its recently observed power dependence in experiments has not been well understood or predicted in theory. In this work, the power dependent scalings of density limit are obtained based on the plasma-wall self-organization theory [D.F. Escande 2022 NF], which are able to match the power dependence of density limits in multiple tokamak devices. The key factors influencing the power dependence are found to be the plasma-wall sputtering and the particle confinement time. The effects of non-sputtered impurities and fusion products are further evaluated. This PWSO-density limit model is then extended to the burning plasma regime and used to predict the conditions for entering burning plasma. Copyright © 2025, The Authors. All rights reserved.

关键词： Tokamak devices

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Effects of Boundary Current on electromagnetic Dispersion Characteristics for a Relativistic Electron Beam

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Plasma Science and technology 2016年第1期18卷 51-57页

作者：肖集雄曾中夏冬辉王之江刘昌海 State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology

With betatron oscillation characteristics of the electron beam and ion channel effect taken into account,dispersion characteristics of electrostatic modes and TM modes for a relativistic electron beam guided by ion channel are *** relations are derived and solved numerically to investigate the dependence of the dispersion characteristics for electrostatic modes and TM modes on the betatron oscillation frequency and the ratio of the relativistic electron beam radius to the waveguide *** effects of the boundary current on the dispersion characteristic of the TM modes and the interaction between the betatron modes and TM modes are *** considering the boundary current,for a strong ion channel,a new low-frequency branch of the TM modes arises and the interaction frequency between the betatron modes and the TM01modes is increased with the same parameters.

关键词： dispersion characteristics electromagnetic eigenmodes betatron oscillation ion channel

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Grid Forming Converters in Renewable Energy Sources Dominated Power Grid:Control Strategy,Stability,Application,and Challenges

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Journal of Modern Power Systems and Clean Energy 2021年第6期9卷 1239-1256页

作者： Haobo Zhang Wang Xiang Weixing Lin Jinyu Wen State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology TBEA Sunoasis Company Ltd. the State Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science and Technology

The renewable energy sources(RESs)dominated power grid is an envisaged infrastructure of the future power system,where the commonly used grid following(GFL)control for grid-tied converters suffers from lacking grid support capability,low stability,***,emerging grid forming(GFM)control methods have been proposed to improve the dynamic performance and stability of grid-tied *** paper reviews existing GFM control methods for the grid-tied converters and compares them in terms of control structure,grid support capability,fault current limiting,and *** the impact of fault current limiting strategies,a comprehensive transient stability analysis is *** addition,this paper explores the typical applications of GFM converters,such as AC microgrid and offshore wind farm high-voltage direct current(OWF-HVDC)integration ***,the challenges to the GFM converters in future applications are discussed.

关键词： Grid following(GFL)control grid forming(GFM)control high-voltage direct current(HVDC) microgrid renewable energy small-signal stability transient stability

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Photonic axion insulator

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Science (New York, N.Y.) 2025年第6730期387卷 162-166页

作者： Liu, Gui-Geng Mandal, Subhaskar Xi, Xiang Wang, Qiang Devescovi, Chiara Morales-Pérez, Antonio Wang, Ziyao Yang, Linyun Banerjee, Rimi Long, Yang Meng, Yan Zhou, Peiheng Gao, Zhen Chong, Yidong García-Etxarri, Aitzol Vergniory, Maia G. Zhang, Baile Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Singapore Research Center for Industries of the Future Department of Electronic and Information Engineering School of Engineering Westlake University Hangzhou China School of Electrical Engineering and Intelligentization Dongguan University of Technology Dongguan China National Laboratory of Solid State Microstructures School of Physics Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjing China Donostia International Physics Center Donostia-San Sebastian Spain Institute for Theoretical Physics ETH Zurich Zurich Switzerland Material and Applied Physics Department University of the Basque Country (UPV/EHU) Donostia-San Sebastián Spain Department of Electronic and Electrical Engineering Southern University of Science and Technology Shenzhen China National Engineering Research Center of Electromagnetic Radiation Control Materials Key Laboratory of Multi-spectral Absorbing Materials and Structures of Ministry of Education University of Electronic Science and Technology of China Chengdu China State Key Laboratory of Optical Fiber and Cable Manufacture Technology Department of Electronic and Electrical Engineering Guangdong Key Laboratory of Integrated Optoelectronics Intellisense Southern University of Science and Technology Shenzhen China Centre for Disruptive Photonic Technologies Photonics Institute Nanyang Technological University Singapore IKERBASQUE Basque Foundation for Science Bilbao Spain Max Planck Institute for Chemical Physics of Solids Dresden Germany Département de Physique et Institut Quantique Université de Sherbrooke Sherbrooke Canada

Axions, hypothetical elementary particles that remain undetectable in nature, can arise as quasiparticles in three-dimensional crystals known as axion insulators. Previous implementations of axion insulators have largely been limited to two-dimensional systems, leaving their topological properties in three dimensions unexplored in experiment. Here, we realize an axion insulator in a three-dimensional photonic crystal and probe its topological properties. Demonstrated features include half-quantized Chern numbers on each surface that resembles a fractional Chern insulator, unidirectional chiral hinge states forming topological transport in three dimensions, and arithmetic operations between fractional and integer Chern numbers. Our work experimentally establishes the axion insulator as a three-dimensional topological phase of matter and enables chiral states to form complex, unidirectional three-dimensional networks through braiding.

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A Profit-Sharing Mechanism for Coordinated Power-Traffic System

arXiv

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arXiv 2025年

作者： Sima, Tianyu Yan, Mingyu Wen, Jianfeng Luo, Wensheng Malinowski, Mariusz State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering Huazhong University of Science and Technology Wuhan430074 China Department of Electrical Engineering and Electronics University of Liverpool LiverpoolL69 3GJ United Kingdom School of Electrical Engineering and Automation Harbin Institute of Technology Harbin150001 China Institute of Control and Industrial Electronics Warsaw University of Technology Warsaw Poland

During the scheduling process, the traffic network operator (TNO) and the distribution network operator (DNO) act non-cooperatively. Under the TNO's management, the distribution of charging loads may exacerbate the local supply-demand imbalance in the power distribution network (PDN), which negatively impacts the economic operation of the PDN. This paper proposes a profit-sharing mechanism based on the principle of incentive compatibility for coordinating the traffic network (TN) and the PDN to minimize the operation cost of PDN. Under this mechanism, the scheduling process of the power-traffic system is divided into two stages. At the pre-scheduling stage, the TNO allocates traffic flow and charging loads without considering the operation of the PDN, after which the DNO schedules and obtains the original cost. At the rescheduling stage, the DNO shares part of benefits of the optimal operation to the TNO to re-dispatch the EVs’ charging to obtain a more effective charging plan, thus minimize the overall cost of PDN. Then, a bilevel model is developed to simulate the operation of the power-traffic system with the proposed sharing scheme and identify the best sharing ratio. Finally, numerical results demonstrate that the PDN can achieve the minimum total cost and simultaneously the TN can also benefit from the proposed profit-sharing mechanism. © 2025, CC BY-NC-ND.

关键词： Profitability

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High-contrast in vivo fluorescence imaging exploiting wavelengths beyond 1880 nm

引用

Nature Communications 2025年第1期16卷 1-12页

作者： Li, Jiayi Xia, Qiming Wu, Tianxiang Zhang, Yuhuang Peng, Shiyi Li, Yifei Li, Yixuan Lin, Hui Zhang, Mingxi Qian, Jun State Key Laboratory of Extreme Photonics and Instrumentations Centre for Optical and Electromagnetic Research College of Optical Science and Engineering International Research Center for Advanced Photonics Zhejiang University Hangzhou China Department of General Surgery Sir Run Run Shaw Hospital Zhejiang University School of Medicine Hangzhou China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan China

The second near-infrared (NIR-II) window is widely acknowledged for its excellent potential in in vivo fluorescence imaging. Currently, NIR-II fluorescence imaging predominantly operates within the 900-1880 nm spectral range, while the region beyond 1880 nm has been disregarded due to the large light absorption of water. Based on a refined understanding of the effect of light absorption on imaging, we propose an approach that utilizes the previously neglected region surrounding the water absorption peak at ~1930 nm for imaging. Both simulations and experiments confirm that the water absorption contributes positively to imaging, enabling high-contrast in vivo fluorescence imaging in the 1880-2080 nm window. To further assess the applicability of this approach in different biological media, we extend our focus to fluorescence imaging in adipose tissue. This leads to the expansion of the imaging window to 1700-2080 nm, owing to the unique light absorption characteristics of adipose tissue. Our results demonstrate that the 1700-2080 nm region provides optimal imaging quality in adipose tissue, attributing to its moderate absorption and low scattering. This work advances our understanding of the interplay between light absorption and photon scattering in bioimaging, providing an insight for selecting optimal imaging windows to achieve high-contrast fluorescence imaging. © The Author(s) 2025.

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