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50th Annual Conference of the IEEE Industrial Electronics Society, IECON 2024

作者： Zhang, Jiamei Sun, Kai Department of Electrical Engineering State Key Laboratory of Power System Operation and Control Tsinghua University Beijing China

ISBN: (纸本)9781665464543

The voltage support capability of renewable resources (RES) is emphasized by grid codes for stable and secure operation faced with grid faults. However, there is another problem occurs when the penetration of RES is boosting. The capability occupation due to injected power for voltage support leads to the decrease of output power for loads, which may result in frequency issues when the inertia of the system decreases. To guarantee the voltage and frequency security during fault ride through (FRT) process, this paper proposes an optimal scheduling scheme for PV-BES system considering voltage support and frequency regulation. In the optimal model, in order to map the voltage and frequency constraints into power constraints, the evaluation model of required injected power for voltage support is formulated firstly. Based on center of inertia theorem and time scale characteristics of FRT, the frequency deviation is represented by distributed generator (DG) adjustment. The voltage and frequency constraint are incorporated into the optimal scheduling model and the quasi-steady-state of the PV-BES system during FRT can be analyzed. The proposed method is fully tested, and the results demonstrate that with the proposed method, the voltage and frequency security can be well guaranteed. © 2024 IEEE.

关键词： Renewable energy

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Characteristics of perfluoromethyl vinyl ether:A new eco-friendly alternative gas for SF_(6)

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High Voltage 2024年第3期9卷 509-517页

作者： Song Xiao Yijiang Chen Mingjun Tang Shuangshuang Tian Haoran Xia Yifan Wang Ju Tang Yi Li Xiaoxing Zhang State Key Laboratory of Power Grid Environmental Protection School of Electrical Engineering and AutomationWuhan UniversityHubeiChina Key Laboratory for High-Efficiency Utilization of Solar Energy and Operation Control of Energy Storage System School of Electrical and Electronic EngineeringHubei University of TechnologyWuhanChina

The exploration of eco-friendly insulating gas to substitute the most potent greenhouse gas sulphur hexafluoride(SF6)has consistently garnered significant ***,the au-thors evaluated the feasibility of utilising perfluoromethyl vinyl ether(PMVE,C_(3)F_(6)O)as a new branch of eco-friendly insulating gas for the first *** primary dielectric and stability characteristics of PMVE regarding AC breakdown,partial discharge,dielectric recovery,and decomposition properties were revealed under various gas pressure and electrical field *** was found that PMVE demonstrated superior dielectric strength,with the AC breakdown and PD inception voltage(PDIV)1.10 and 1.14 times that of pure SF_(6).Furthermore,the dielectric strength of PMVE exhibits stability even after undergoing 100 cycles of AC breakdowns,and there is no observable formation of solid precipitation on the electrode *** discharge decomposition of PMVE mainly generates fluorocarbon(CF_(4),C_(2)F_(6),C_(3)F_(6),C_(3)F_(8),etc.)and ***,the exceptional insulation stabilityandno absence of solidprecipitation featuresendow PMVE tobe utilised as a new eco-friendly gas for SF_(6)-free gas-insulated equipment.

关键词： surface dielectric vinyl

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Erosion Analysis of Static Components in Slurry Pumps Based on Reverse Modeling

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Fluid Dynamics & Materials Processing 2025年第3期21卷 589-603页

作者： Zhengjing Shen Fanqiang Kong Yu Liu Jilai Zeng Wengang Yang Jiangbo Wu School of College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou730050China Key Laboratory of Advanced Pumps Valves and Fluid Control SystemMinistry of EducationLanzhou730050China

Erosion in slurry pumps presents a persistent challenge in industrial *** study examines the erosion of the static components of a 150ZJ-C42 centrifugal slurry pump,currently in operation at a beneficiation plant,under varying particle *** high-precision three-dimensional reverse engineering,the pump’s flow passage geometry was reconstructed to facilitate detailed erosion *** on the front and rear baffles of the pump chamber,as well as the volute,erosion patterns were analyzed for different particle volume concentrations and *** results reveal that the highest erosion damage consistently occurs near the volute tongue,with wear being most severe in regions adjacent to the partition plate near the rear *** damage intensity in this area correlates positively with particle ***,the average erosion rate in the volute surpasses that of the front and rear chamber liners,reaching a value as high as 6.03×10^(-7)kg·m^(-2)·s^(-1)at a particle concentration of 9%and diameter of 0.1 mm,adversely impacting pump *** the pump chamber baffles,increased erosion is observed at a particle diameter of 0.05 mm under constant volume concentration conditions,while higher particle concentrations exacerbate localized erosion.

关键词： Slurry pump reverse modeling numerical simulation erosion solid-liquid two-phase flow

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Influence of Thermal Conductivity of Multi-scale Particles Epoxy Composites on High-Frequency Electrical Insulation Property 5

Influence of Thermal Conductivity of Multi-scale Particles E...

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5th IEEE International Conference on Dielectrics, ICD 2024

作者： Song, Yan-Hui Dang, Zhi-Min Tsinghua University State Key Laboratory of Power System Operation and Control Department of Electrical Engineering Beijing China

ISBN: (纸本)9798350308976

Epoxy, with excellent electrical insulation properties, processing performance, and low price, is commonly used for transformers (110kV and below) and power electronic transformers (high-frequency transformers) as the primary insulating material. Since the thermal conductivity of epoxy resins is only 0.2 W/(m·K), the electrical insulation properties decline significantly at high frequency. Preparing epoxy composites with high thermal conductivity and excellent electrical insulation at high frequencies is a great challenge for industrial production. It is considered that SiO2 (9 eV), BN (5.9 eV), and Al2O3 (7.2-8.8 eV) are thermally conductive particles with good electrical insulation properties. The materials filled with different micron-scale particles have higher thermal conductivity than the nanofilled materials. In this study, 5 μm SiO2, 25 μm BN, and 40 μm Al2O3 were used as fillers, and the filler ratios were calculated according to the Dinger-Funk model, focusing on the effects of the variation of filler content on thermal conductivity and electrical insulation properties. The thermal conductivity of the epoxy composites improved with the increase of filler content up to 1.003 W/(m·K), while the AC breakdown field strength gradually decreased. However, the breakdown time at 20 kHz, 35 kV/mm bipolar square wave appeared to increase and then decrease with the increase of content. Therefore, the optimum content of fillers allows the preparation of efficient epoxy composites as insulating materials for power electronic transformers. This study provides ideas for designing thermally conductive composites operating at high frequency and high voltage fields. © 2024 IEEE.

关键词： epoxy resin high frequency bipolar square wave inorganic particle compounding thermal conductive electrical insulation

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Unmanned Ship Identification Based on Improved YOLOv8s Algorithm

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Computers, Materials & Continua 2024年第3期78卷 3071-3088页

作者： Chun-Ming Wu Jin Lei Wu-Kai Liu Mei-Ling Ren Ling-Li Ran Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology School of Electrical EngineeringNortheast Electric Power UniversityJilin132012China School of Biomedical Engineering Taiyuan University of TechnologyTaiyuan030600China

Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes an infrared ship detection model based on the improved YOLOv8 algorithm(R_YOLO).The algorithm incorporates the Efficient Multi-Scale Attention mechanism(EMA),the efficient Reparameterized Generalized-feature extraction module(CSPStage),the small target detection header,the Repulsion Loss function,and the context aggregation block(CABlock),which are designed to improve the model’s ability to detect targets at multiple scales and the speed of model *** algorithm is validated in detail on two vessel *** comprehensive experimental results demonstrate that,in the infrared dataset,the YOLOv8s algorithm exhibits improvements in various performance ***,compared to the baseline algorithm,there is a 3.1%increase in mean average precision at a threshold of 0.5(mAP(0.5)),a 5.4%increase in recall rate,and a 2.2%increase in mAP(0.5:0.95).Simultaneously,while less than 5 times parameters,the mAP(0.5)and frames per second(FPS)exhibit an increase of 1.7%and more than 3 times,respectively,compared to the CAA_YOLO ***,the evaluation indexes on the visible light data set have shown an average improvement of 4.5%.

关键词： Unmanned ships R_YOLO EMA CSPStage YOLOv8s

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Characteristics of controlled Bridge Circuit and Its Application in Magnetic Field Induction Measurement

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Tsinghua Science and Technology 2024年第4期29卷 1105-1117页

作者： Yanchu Li Qingqing Ding Mingchen Yan Jiyao Wang Jun Xu Xinzhou Dong Department of Electrical Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Control and Simulation of Power System and Generation Equipments Tsinghua UniversityBeijing 100084China School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing 100096China

The article designs a new type of bridge circuit with a controlled source—when the resistance on the bridge arm of the controlled source bridge circuit meets the bridge balance condition, and the bridge branch contains only one Current-controlled Current Source (CCCS), a Voltage-controlled Current Source (VCCS), a Current-controlled Voltage Source (CCVS), or a Voltage-controlled Voltage Source (VCVS), the circuit is called a controlled bridge circuit, which has the characteristics of bridge balance. Due to the relationship between the controlled source and the bridge arm, the sensitivity of the components on the bridge is higher mathematically and logically. When applied to measurement, engineering, automatic control, and other fields, the controlled bridge circuit has higher control ac-curacy. Mathematical derivation and simulation results prove the correctness of the bridge balance conclusion and the special properties of this bridge when applied to the measurement field.

关键词： bridge bircuit bridge circuit applications bridge balanced condition controlled bridge circuit magnetic field induction measurement

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Time-Varying Formation Tracking control of Heterogeneous Multi-Agent systems With Intermittent Communications and Directed Switching Networks

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 294-296页

作者： Yuhan Wang Zhuping Wang Hao Zhang Huaicheng Yan the Shanghai Research Institute for Intelligent Autonomous Systems Tongji University the National Key Laboratory of Autonomous Intelligent Unmanned Systems the Frontiers Science Center for Intelligent Autonomous System of Ministry of Education the College of Electronic and Information Engineering the Department of Control Science and Engineering Tongji University the Key Laboratory of Advanced Control and Optimization for Chemical Processes of Ministry of Education the School of Information Science and Engineering East China University of Science and Technology

Dear Editor,This letter is concerned with the problem of time-varying formation tracking for heterogeneous multi-agent systems(MASs) under directed switching networks. For this purpose, our first step is to present so... 详细信息

关键词： Switches Topology Observers Formation control Event detection Switched systems Multi-agent systems control theory Autonomous systems Stability

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Thickness Measurement of Single-Mode Fiber Coating Layer Based on Forward Brillouin Scattering

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IEEE Sensors Journal 2025年第11期25卷 19332-19340页

作者： Zhang, Yongqi Wang, Tao Liu, Yijia Liu, Li Zhang, Mingjiang Taiyuan University of Technology Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education College of Physics and Optoelectronic Engineering Taiyuan030024 China Taiyuan University of Technology Shanxi Key Laboratory of Precision Measurement Physics College of Physics and Optoelectronic Engineering Taiyuan030024 China

The coating layer is essential for protecting and applying optical fibers. Nowadays, the thickness measurement of the coating layer relies on point measurement schemes such as the side-looking light distribution method and mechanical method. However, there are some problems with the above methods, such as the trade-off between resolution and field of view, the cutting of the measurement position and the long measurement time. To overcome these problems, we propose a new method based on forward Brillouin scattering, which measures the coating layer thickness of single-mode fibers. The physical properties of the transverse acoustic field involved in forward Brillouin scattering make it possible to measure the thickness of the fiber coating. The corresponding relationship between the transverse acoustic mode frequency and the diameter of the coating layer can be calculated. The coating layer thickness can be measured with high precision by measuring the frequency spectrum of forward Brillouin scattering corresponding to multiple transverse acoustic modes at a given temperature. In the verification experiment, three types of single-mode fibers coated with polyimide are used as the sensing fiber to measure the thickness of the coating layer at multiple temperatures. The experimental results show that the error in the coating layer thickness obtained is less than 0.05 μm. To the best of our knowledge, this is the first demonstration of non-destructive, high-precision monitoring of fiber coating thickness. © 2001-2012 IEEE.

关键词： Acoustic field measurement

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Impact time control guidance against maneuvering targets based on a nonlinear virtual relative model

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Chinese Journal of Aeronautics 2023年第7期36卷 444-459页

作者： Yuru BIN Hui WANG Defu LIN Yaning WANG Xin SUN School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of UAV Autonomous Control Beijing Institute of TechnologyBeijing 100081China Beijing Institute Of Electronic System Engineering Beijing 100854China

Aiming at the problem of high-precision interception of air-maneuvering targets with impact time constraints,this paper proposes a novel guidance law based on a nonlinear virtual relative model in which the origin is attached to the *** this way,the original maneuvering target is transformed into a stationary one.A polynomial function of the guidance command in the range domain with two unknown coefficients is introduced into the virtual model,one of the coefficients is determined to achieve the impact time constraint,and the other is determined to satisfy a newly defined virtual look angle *** meeting the terminal constraints simultaneously,the guidance command can finally be *** resulting solution is represented as a combination of proportional navigation guidance-like term which is aimed to meet the zero miss distance constraint,a bias term for impact time control by adjusting the length of the homing trajectory,and an additional term for target *** simulations demonstrate that the proposed law achieves an acceptable impact time error for various initial conditions against different types of maneuvering targets and shows more effective performance in comparison with those of other existing guidance laws.

关键词： Impact time control Maneuvering targets Polynomial guidance Virtual relative model Virtual look angle constraint

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Low-Carbon Dispatching for Virtual Power Plant with Aggregated Distributed Energy Storage Considering Spatiotemporal Distribution of Cleanness Value

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Journal of Modern Power systems and Clean Energy 2024年第2期12卷 346-358页

作者： Hongchao Gao Tai Jin Guanxiong Wang Qixin Chen Chongqing Kang Jingkai Zhu State Key Laboratory of Power System Operation and Control Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Sichuan Energy Internet Research Institute Tsinghua University Chengdu 200016China Power Dispatching and Control Center of Shanghai Municipal Electric Power Company Shanghai 200122China IEEE

The scale of distributed energy resources is increasing,but imperfect business models and value transmission mechanisms lead to low utilization ratio and poor *** address this issue,the concept of cleanness value of distributed energy storage(DES)is proposed,and the spatiotemporal distribution mechanism is discussed from the perspectives of electrical energy and *** on this,an evaluation system for the environmental benefits of DES is constructed to balance the interests between the aggregator and the power system ***,an optimal low-carbon dispatching for a virtual power plant(VPP)with aggregated DES is constructed,where-in energy value and cleanness value are both *** achieve the goal,a green attribute labeling method is used to establish a correlation constraint between the nodal carbon potential of the distribution network(DN)and DES behavior,but as a cost,it brings multiple nonlinear ***,a solution method based on the convex envelope(CE)linear re-construction method is proposed for the multivariate nonlinear programming problem,thereby improving solution efficiency and ***,the simulation verification based on the IEEE 33-bus DN is *** simulation results show that the multidimensional value recognition of DES motivates the willingness of resource users to ***,resolving the impact of DES on the nodal carbon potential can effectively alleviate overcompensation of the cleanness value.

关键词： Distributed energy storage virtual power plant(VPP) spatiotemporal distribution low-carbon dispatching

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