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Numerical simulation of the initial plasma formation and current transfer in single-wire electrical explosion in vacuum 被引量:2
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作者 王坤 史宗谦 +4 位作者 石元杰 白骏 吴坚 贾申利 邱爱慈 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期256-261,共6页
In this paper, a computational model is constructed to investigate the phenomenon of the initial plasma formation and current transfer in the single-wire electrical explosion in a vacuum. The process of the single-wir... In this paper, a computational model is constructed to investigate the phenomenon of the initial plasma formation and current transfer in the single-wire electrical explosion in a vacuum. The process of the single-wire electrical explosion is divided into four stages. Stage Ⅰ: the wire is in solid state. Stage Ⅱ: the melting stage. Stage Ⅲ: the wire melts completely and the initial plasma forms. Stage IV: the core and corona expand separately. The thermodynamic calculation is applied before the wire melts completely in stages Ⅰ and Ⅱ. In stage Ⅲ, a one-dimensional magnetohydrodynamics model comes into play until the instant when the voltage collapse occurs. The temperature, density, and velocity, which are derived from the magnetohydrodynamics calculation, are averaged over the distribution area. The averaged parameters are taken as the initial conditions for stage Ⅳ in which a simplified magnetohydrodynamics model is applied. A wide-range semi-empirical equation of state, which is established based on the Thomas-Fermi-Kirzhnits model, is constructed to describe the phase transition from solid state to plasma state. The initial plasma formation and the phenomenon of current transfer in the electrical explosion of aluminum wire are investigated using the computational model. Experiments of electrical explosion of aluminum wires are carried out to verify this model. Simulation results are also compared with experimental results of the electrical explosion of copper wire. 展开更多
关键词 single-wire electrical explosion plasma formation current transfer
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Significant effect of electron transfer between current collector and active material on high rate performance of Li_4Ti_5O_(12) 被引量:1
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作者 潘慧霖 胡勇胜 +1 位作者 李泓 陈立泉 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期9-12,共4页
The rate and cycling performances of the electrode materials are affected by many factors in a practical complicated electrode process. Learning about the limiting step in a practical electrochemical reaction is very ... The rate and cycling performances of the electrode materials are affected by many factors in a practical complicated electrode process. Learning about the limiting step in a practical electrochemical reaction is very important to effectively improve the electrochemical performances of the electrode materials. Li4Ti5O12, as a zero-strain material, has been considered as a promising anode material for long life Li-ion batteries. In this study, our results show that the Li4Ti5O12 pasted on Cu or graphite felt current collector exhibits unexpectedly higher rate performance than on A1 current collector. For Li4Ti5O12, the electron transfer between current collector and active material is the critical factor that affects its rate and cycling performances. 展开更多
关键词 LI4TI5O12 current collector electron transfer Li-ion batteries
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Arc Characteristic and Metal Transfer of Pulse Current Horizontal Flux-Cored Arc Welding 被引量:1
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作者 Fangjie Cheng Shuai Zhang +2 位作者 Xinjie Di Dongpo Wang Jun Cao 《Transactions of Tianjin University》 EI CAS 2017年第2期101-109,共9页
In this work, we utilized high-speed video photography to investigate the arc characteristics, metal transfer behavior, and welding spatter of the pulse-current flux-cored arc welding (P-FCAW) process in the horizonta... In this work, we utilized high-speed video photography to investigate the arc characteristics, metal transfer behavior, and welding spatter of the pulse-current flux-cored arc welding (P-FCAW) process in the horizontal position. The results indicate the presence of a stable “flux pole” during both the pulse-on and pulse-off periods when the mean current ranged from 140 to 170 A. The existence of this “flux pole” was beneficial for droplet transfer in the “axial droplet transfer” mode. With respect to welding spatter, with an increase in the welding current, we observed three kinds of spatter—explosive spatter, rebounded droplet spatter, and scattering spatter. With an increase in the pulse current from 310.6 to 345.6 A, the deflection of the arc reduced from 30.4° to 16.6°, which positively influenced the arc rigidity, particularly in the horizontal position. © 2017, Tianjin University and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Bridge decks DROPS Electric arc welding Flux cored arc welding (FCAW) High speed cameras High speed photography POLES Welding
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Analysis and Simulation on Current Commutation of DC Transfer Switches in UHVDC Transmission Systems 被引量:1
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作者 PENG Chang WEN Jialiang MA Guohua WANG Xiuhuan LIU Zhigang YU Kunshan 《中国电机工程学报》 EI CSCD 北大核心 2011年第36期I0001-I0001,共1页
关键词 高压直流输电系统 转换开关 仿真 换流 操作模式 电流
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Modeling transient fluid flow and heat transfer phenothena in stationary pulsed current TIG weld pool 被引量:1
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作者 Zheng Wei Wu Chuansong and Wu Lin(Harbin Institute of Technology, Harbin) 《China Welding》 EI CAS 1995年第2期139-149,共11页
A mathematical model is presented to describe transient behavior of heat transfer and fluid flow in stationary pulsed current tungsten inert gas (PC-TIG) weld pool, which considers three kinds of driving, forces for w... A mathematical model is presented to describe transient behavior of heat transfer and fluid flow in stationary pulsed current tungsten inert gas (PC-TIG) weld pool, which considers three kinds of driving, forces for weld pool convection, i,e. buoyancyforce, electromagnetic force and surface tension force. furthermore. the effect of vaporization heat flux at the free surface of weld pool and the temperature coefficient of surface tenston which is a function of temperatuer and composition are considered in the model In order to accelerate the convergence of iteration the AST(additive source term)method which concerns with the thermal energv boundary conditions is extended successfully to deal with the momentum boundary conditions by which the transient momentum equation and energy equation are mutually coupled. At the same time. ADI (Alternating direction implicit) method and DBC (double blocks correction) technque are employed to solve the finite difference equations. The results of numerical simulation demonstrate the transient behavior of PC-TIG weld pool, as well as the periodic variation of fluid flow and heat transfer with the periodic variation of welding current in stationary PC-TIG weld pool. The theoretical predictions based on this model are, shown to be in good accordance with the experimental measurements. 展开更多
关键词 numerical simulation pulsed current TIG. weld pool. fluid flow. heat transfer
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Observation of a Current Plateau in the Transfer Characteristics of InGaN/AlGaN/AlN/GaN Heterojunction Field Effect Transistors
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作者 闫俊达 王权 +11 位作者 王晓亮 肖红领 姜丽娟 殷海波 冯春 王翠梅 渠慎奇 巩稼民 张博 李百泉 王占国 侯洵 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期113-116,共4页
Direct-current transfer characteristics of (InGaN)/A1GaN/A1N/GaN heterojunction field effect transistors (HFETs) are presented. A drain current plateau (IDs = 32.0 mA/mm) for Vcs swept from +0.7 V to -0. 6 V is... Direct-current transfer characteristics of (InGaN)/A1GaN/A1N/GaN heterojunction field effect transistors (HFETs) are presented. A drain current plateau (IDs = 32.0 mA/mm) for Vcs swept from +0.7 V to -0. 6 V is present in the transfer characteristics of InGaN/AIGaN/AIN/GaN HFETs. The theoretical calculation shows the coexistence of two-dimensional electron gas (2DEG) and two-dimensional hole gas (2DHG) in InGaN/AIGaN/A1N/GaN heterostructures, and the screening effect of 2DHG to the 2DEG in the conduction channel can explain this current plateau. Moreover, the current plateau shows the time-dependent behavior when IDs Vcs scans repeated are conducted. The obtained insight provides indication for the design in the fabrication of GaN-based super HFETs. 展开更多
关键词 AlGaN Observation of a current Plateau in the transfer Characteristics of InGaN/AlGaN/AlN/GaN Heterojunction Field Effect Transistors INGAN AlN
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Simulation of droplet transfer process and current waveform control of CO_2 arc welding
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作者 俞建荣 吴立志 《中国有色金属学会会刊:英文版》 CSCD 2001年第5期667-670,共4页
A simulation system used in the arc welding short circuit transfer process and current waveform control process was developed in this paper. The simulation results are basically consistent with welding technical exper... A simulation system used in the arc welding short circuit transfer process and current waveform control process was developed in this paper. The simulation results are basically consistent with welding technical experiments. The simulation system can be used to simulate and test the current waveform control parameters with welding variables. By this simulation system, the influence regularities of the current waveform control parameters in the CO 2 arc welding droplet short circuit transfer process can be got. Moreover, the basic mode of real time current waveform control can be also established by the simulation testing. 展开更多
关键词 CO 2 arc welding droplet transfer current waveform control computer simulation
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Effects of Hall Current on MHD Boundary Layer Second-Order Viscoelastic Fluid Flow Induced by a Continuous Surface with Heat Transfer
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作者 Haider Zaman Murad Ali Shah +1 位作者 Farhan Khan Qaiser Javed 《American Journal of Computational Mathematics》 2014年第3期143-152,共10页
Effects of Hall current on heat transfer and magnetohydrodynamic (MHD) boundary layer flow induced by a continuous surface in a parallel free stream of a second-order viscoelastic fluid are studied for uniform suction... Effects of Hall current on heat transfer and magnetohydrodynamic (MHD) boundary layer flow induced by a continuous surface in a parallel free stream of a second-order viscoelastic fluid are studied for uniform suction/injection by taking viscous dissipation into account. Complex nonsimilar solutions to the stream function and temperature are developed by means of an elegant technique, known as homotopy analysis method (HAM). Convergence of the solutions is ensured with the help of -curves. Graphical and tabular results for the effects of Hall current reveal that it has a significant influence on: complex velocity, complex temperature, magnitude of the shear stress at the surface, magnitude of the rate of heat transfer at the surface and on boundary layer thickness. 展开更多
关键词 HALL currentS Heat transfer Boundary Layer Complex Nonsimilar Solutions HAM
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Charge transfer on porous silicon membranes studied by current-sensing atomic force microscopy
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作者 Bing Xia Qiang Miao +3 位作者 Jie Chao Shou Jun Xiao Hai Tao Wang Zhong Dang Xiao 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期199-202,共4页
A visible rectification effect on the current-voltage curves of metal/porous silicon/p-silicon has been observed by current-sensing atomic force microscopy. The current-voltage curves of porous silicon membranes with ... A visible rectification effect on the current-voltage curves of metal/porous silicon/p-silicon has been observed by current-sensing atomic force microscopy. The current-voltage curves of porous silicon membranes with different porosities, prepared through variation of etching current density for a constant time, indicate that a higher porosity results in a higher resistance and thus a lower rectification, until the current reaches a threshold at a porosity 〉55%. We propose that the conductance mode in the porous silicon membrane with porosities 〉55% is mainly a hopping mechanism between nano-crystallites and an inverse static electric field between the porous silicon and p-Si interface blocks the electron injection from porous silicon to p-Si, but with porosities ≤55%, electron flows through a direct continuous channel between nano-crystallites. 展开更多
关键词 Porous silicon current sensing AFM Electron transfer POROSITY
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Finite element solution of heat and mass transfer flow with Hall current,heat source,and viscous dissipation
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作者 S.SIVAIAH R.SRINIVASA-RAJU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第5期559-570,共12页
The aim of the paper is to investigate the effect of heat and mass transfer on the unsteady magnetohydrodynamic free convective flow with Hall current, heat source, and viscous dissipation. The problem is governed by ... The aim of the paper is to investigate the effect of heat and mass transfer on the unsteady magnetohydrodynamic free convective flow with Hall current, heat source, and viscous dissipation. The problem is governed by the system of coupled non-linear partial differential equations whose exact solution is difficult to obtain. Therefore, the problem is solved by using the Galerkin finite element method. The effects of the various parameters like Hall current, Eckert number, heat source parameter, Prandtl number, and Schmidt number on the velocity components, the temperature, and the concentration are also examined through graphs. 展开更多
关键词 heat and mass transfer Hall current viscous dissipation heat generation
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Analysis on the Transfer Characteristics of Rogowski-coil Current Transformer and Its Influence on Protective Relaying
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作者 Yi Wang Jiaman Li +3 位作者 Yulan Hu Ranran An Zexiang Cai Ruiwen He 《Energy and Power Engineering》 2013年第4期1324-1329,共6页
This paper systematically analyzes the transfer characteristics of the Rogowski-coil Current Transformer and its effect on protective relaying through theoretical analysis, experiments and simulations. The frequency c... This paper systematically analyzes the transfer characteristics of the Rogowski-coil Current Transformer and its effect on protective relaying through theoretical analysis, experiments and simulations. The frequency characteristics and transient characteristics of Rogowski transducer and Rogowski-coil Current Transformer are deeply analyzed based on the physical structure of the transformer.?It is revealed that broad bandwidth of the transformer can improve the performance of protective relaying, and the bandwidth is determined mainly by the parameters of the Rogowski transducer and signal processing circuits. It is also discovered that the measurement errors of transient current mainly depend on the abilities for the current transformer to reproduce an accurate replica of the decaying dc components, which is mainly decided by the decay time constant of the aperiodic component of transient current and the parameters of the integral unit. Finally, some measures are proposed for the performance improvement of Rogowski-coil Current Transformer to meet the requirements of protective relaying system in terms of structural design and testing standards. 展开更多
关键词 current TRANSFORMER Rogowski-coil transfer Characteristics Protective RELAYING
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Numerical Solution of MHD Convection and Mass Transfer Flow of Viscous Incompressible Fluid about an Inclined Plate with Hall Current and Constant Heat Flux
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作者 Mohammad Wahiduzzaman Runu Biswas +2 位作者 Md. Eaqub Ali Md. Shakhaoath Khan Ifsana Karim 《Journal of Applied Mathematics and Physics》 2015年第12期1688-1709,共22页
The present numerically study investigates the influence of the Hall current and constant heat flux on the Magneto hydrodynamic (MHD) natural convection boundary layer viscous incompressible fluid flow in the manifest... The present numerically study investigates the influence of the Hall current and constant heat flux on the Magneto hydrodynamic (MHD) natural convection boundary layer viscous incompressible fluid flow in the manifestation of transverse magnetic field near an inclined vertical permeable flat plate. It is assumed that the induced magnetic field is negligible compared with the imposed magnetic field. The governing boundary layer equations have been transferred into non-similar model by implementing similarity approaches. The physical dimensionless parameter has been set up into the model as Prandtl number, Eckert number, Magnetic parameter, Schmidt number, local Grashof number and local modified Grashof number. The numerical method of Nactsheim-Swigert shooting iteration technique together with Runge-Kutta six order iteration scheme has been used to solve the system of governing non-similar equations. The physical effects of the various parameters on dimensionless primary velocity profile, secondary velocity profile, and temperature and concentration profile are discussed graphically. Moreover, the local skin friction coefficient, the local Nusselt number and Sherwood number are shown in tabular form for various values of the parameters. 展开更多
关键词 MHD HEAT and Mass transfer HALL current Inclined Plate CONSTANT HEAT FLUX
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Study on arc characteristics and behavior of metal transfer in pulse current flux-cored arc welding of mild steel 被引量:1
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作者 Zhang Shuai Cheng Fangjie +2 位作者 Di Xinjie Wang Dongpo Cao Jun 《China Welding》 EI CAS 2016年第4期42-51,共10页
The variation in arc characteristics and behavior of metal transfer with the change in pulse parameters has been studied by high speed video camera during pulse current flux-cored arc weld deposition.A comparative stu... The variation in arc characteristics and behavior of metal transfer with the change in pulse parameters has been studied by high speed video camera during pulse current flux-cored arc weld deposition.A comparative study of similar nature has also been carried out during flux-cored arc weld deposition in globular and spray transfer modes.The effect of pulse parameters has been studied by considering their mean current and arc voltage.The arc characteristics studied by its root diameter,projected diameter and length,and the behavior of metal transfer noted by the metal transfer model and the droplet diameter have been found to vary significantly with the pulse parameters.The observation may help in understanding the arc characteristics with respect to the variation in pulse parameters which may be beneficial in using pulse current FCAW to produce desired weld quality. 展开更多
关键词 flux-cored arc welding pulse current mild steel arc characteristics metal transfer the slag column welding spatter
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Hydrophobic ionic liquids/water interfacial phase transfer induced by direct current electric field
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作者 NIU Dongxiao CHEN Jiajia +2 位作者 WANG Wei YANG Xinju HU Jun 《Nuclear Science and Techniques》 SCIE CAS CSCD 2011年第4期240-244,共5页
To investigate the affect of direct current electric field (DCEF) on the interfacial phase,in this paper,a hydrophobic ionic liquid (HIL)/water as liquid-liquid two-phase binary system is established by using the deio... To investigate the affect of direct current electric field (DCEF) on the interfacial phase,in this paper,a hydrophobic ionic liquid (HIL)/water as liquid-liquid two-phase binary system is established by using the deioned water and l-butyl-3-methyl imidazolium hexafluorophosphate,and the topographies of the HIL nanodroplets and nanolayers in ambient water are observed by atomic force microscope (AFM).The results show the AFM exerting the DCEF can enhance the intersolubility of the HIL/water binary system and induce their interfacial phase transfer. 展开更多
关键词 离子液体 直流电场 水界面 相转移 疏水性 电场诱导 原子力显微镜 HIL
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水下湿法脉冲电流焊接熔滴过渡控制机理研究
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作者 杜永鹏 陈晓强 +2 位作者 尤家玉 郭宁 付云龙 《稀有金属材料与工程》 北大核心 2026年第3期674-684,共11页
首先分析了水下湿法焊接排斥过渡形成机理。受水环境影响水下焊接熔滴在焊接过程中受多种力综合作用,熔滴所受气体压力、气体拖曳力、等离子流力受电弧气泡生成部位及阴极斑点位置影响而波动不定,是熔滴发生排斥过渡的主要原因,表面张... 首先分析了水下湿法焊接排斥过渡形成机理。受水环境影响水下焊接熔滴在焊接过程中受多种力综合作用,熔滴所受气体压力、气体拖曳力、等离子流力受电弧气泡生成部位及阴极斑点位置影响而波动不定,是熔滴发生排斥过渡的主要原因,表面张力阻碍熔滴侧向脱离焊丝端部,自身重力则促进熔滴脱离焊丝端部完成过渡。采用正交试验法研究了脉冲电流频率、占空比、峰值电流对水下湿法焊接成形、熔滴过渡、焊接稳定性的影响,采用焊缝余高变异系数来评估成形质量,试验结果表明,当占空比在15%~20%,峰值电流350 A,脉冲频率20 Hz左右时,焊接效果较好,通过施加脉冲电流在峰值电流阶段可以显著增强熔滴所受电磁收缩力,促进熔滴完成过渡,提高过渡频率。 展开更多
关键词 Q235钢 水下湿法焊接 脉冲电流 熔滴过渡
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面向水下无线电能传输系统涡流损耗抑制与效率优化的接收端控制方法研究
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作者 李陶 王懿杰 +5 位作者 李阳 孙智超 麦建伟 崔建 杨傲 徐殿国 《中国电机工程学报》 北大核心 2026年第4期1572-1581,I0023,共11页
针对水下无线电能传输(underwater wireless power transfer,UWPT)系统中涡流损耗对系统传输效率的制约作用,文中提出一种利用接收端阻抗调控进行效率优化的控制策略。通过构建UWPT系统传输效率的数学模型,得到系统最大效率条件,发现UWP... 针对水下无线电能传输(underwater wireless power transfer,UWPT)系统中涡流损耗对系统传输效率的制约作用,文中提出一种利用接收端阻抗调控进行效率优化的控制策略。通过构建UWPT系统传输效率的数学模型,得到系统最大效率条件,发现UWPT系统效率与负载电抗存在强耦合关系;基于“功率优先、效率次优”的原则,利用有源整流保持输出功率稳定为首要控制目标;通过引入辅助H桥并和有源整流器进行协同控制,以副边回路电流相位为调控变量,进行涡流抑制和效率提升。提出辅助H桥和有源整流器的协同控制方法,实现系统阻抗匹配与输出控制双重目标;搭建787 W的实验样机进行验证,实验结果表明:相较于传统LCC-S补偿,所提方法在额定工况下传输效率提升1.58%,对其进行损耗分布分析发现,涡流损耗占比由初始的82.8%降至71.1%,验证了所提协同控制策略在涡流损耗抑制方面的有效性。 展开更多
关键词 水下无线电能传输 涡流损耗 传输效率
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地埋电缆群实时动态载流能力快速评估方法
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作者 司文荣 梁永春 +1 位作者 赵莹莹 傅晨钊 《高压电器》 北大核心 2026年第2期153-161,共9页
准确、快速计算应急负荷和转供负荷工况下地埋电力电缆群暂态缆芯温升对于提高电力电缆动态载流能力精细化管理水平具有重要的意义。首先利用有限元稳态分析获得转移矩阵,利用有限元暂态分析获得单根加热电缆下的自热暂态温升数据和其... 准确、快速计算应急负荷和转供负荷工况下地埋电力电缆群暂态缆芯温升对于提高电力电缆动态载流能力精细化管理水平具有重要的意义。首先利用有限元稳态分析获得转移矩阵,利用有限元暂态分析获得单根加热电缆下的自热暂态温升数据和其余电缆的互热暂态温升数据;然后构建了复合暂态热路模型,加载电缆的自热热路模型由二支路热阻—热容组成,邻近电缆的互热热路模型由一支路热阻—热容组成,给出了复合暂态热路模型的龙格库塔法求解方法;最后以有限元计算结果为基准,利用遗传算法优化求解复合热路模型的热阻和热容参数。针对具体实例,利用转移矩阵获得各电缆稳态温升,通过每一个时间步修正损耗实现热电耦合,利用复合热路模型计算任意一根电缆的动态载流量。与有限元计算结果对比表明,该方法具有较高的精度,可以用于工程中直埋电缆群的应急负荷和转供负荷电流运维管理。 展开更多
关键词 地埋电缆群 复合暂态热路模型 暂态缆芯温升 动态载流量 龙格库塔法 转移矩阵 热电耦合
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地铁杂散电流影响下的电流互感器传变特性分析
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作者 谢昱韬 林圣 +1 位作者 范浩然 王爱民 《电力系统保护与控制》 北大核心 2026年第1期17-27,共11页
我国直流地铁系统大多采用钢轨进行回流,因钢轨对地无法实现完全绝缘,部分回流电流泄漏将形成杂散电流。杂散电流入侵城市电网将导致电磁式电流互感器传变误差增大,甚至造成铁芯饱和、二次电流畸变等不利影响。现有研究普遍基于恒定直... 我国直流地铁系统大多采用钢轨进行回流,因钢轨对地无法实现完全绝缘,部分回流电流泄漏将形成杂散电流。杂散电流入侵城市电网将导致电磁式电流互感器传变误差增大,甚至造成铁芯饱和、二次电流畸变等不利影响。现有研究普遍基于恒定直流影响下的电流互感器传变特性展开分析,并不能准确刻画杂散电流低频正负交变、随机波动的特性以及其对电流互感器传变特性的影响。因此,将杂散电流等效为直流与各低频分量的叠加;结合电流互感器等效电路模型建立微分方程组,推导了电网暂稳态下杂散电流对电流互感器传变特性的影响机理、影响规律及影响因素,并通过仿真分析进行对比验证。结果表明,杂散电流长期作用将引发电流互感器直流偏磁,增大一、二次侧电流幅值差与相角差。杂散电流频率越低、幅值越大,电流互感器饱和程度越深,二次侧电流畸变越严重。 展开更多
关键词 地铁杂散电流 直流偏磁 电流互感器 传变特性
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非隔离混合型三电平柔性潮流转供装置的漏电流抑制和直流电压平衡控制策略
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作者 包明骏 何晋伟 +2 位作者 张宸宇 袁宇波 王成山 《电工技术学报》 北大核心 2026年第4期1298-1310,共13页
针对非隔离型柔性潮流转供装置存在的漏电流抑制难度大、直流电压扰动多、多目标控制耦合性强等问题,该文提出一种三相三线和三相四线制混合的三电平柔性潮流转供装置,并针对该装置研发了共模漏电流直接闭环调节抑制方法和直流电压平衡... 针对非隔离型柔性潮流转供装置存在的漏电流抑制难度大、直流电压扰动多、多目标控制耦合性强等问题,该文提出一种三相三线和三相四线制混合的三电平柔性潮流转供装置,并针对该装置研发了共模漏电流直接闭环调节抑制方法和直流电压平衡控制策略。首先,建立非隔离混合型三电平柔性潮流转供装置的共模等效电路模型,得出共模漏电流的主要分量为3、9次谐波,进而提出共模漏电流特征次谐波分量直接闭环抑制策略。其次,为了应对潮流转供、共模漏电流抑制等过程中双侧变流器中二极管钳位电流引起的直流电压不均衡问题,提出二极管钳位电流的低频特征分量在线估算方法,并基于整流侧中线电流主动谐波注入实现了直流电压的高度均衡。最后,通过实验验证了所提方法的有效性。 展开更多
关键词 柔性潮流转供装置 三电平变流器 漏电流 钳位电流估算 直流电压平衡
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Study on the formation of arc plasma on the resistive wall liquid metal current limiter
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作者 李金金 段雄英 +4 位作者 黄智慧 谢为赢 廖敏夫 马畅 陶佳 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第8期141-152,共12页
Due to its significant attributes,the liquid metal current limiter(LMCL)is considered a new strategy for limiting short-circuit current in the power grid.A resistive wall liquid metal current limiter(RWLMCL)is designe... Due to its significant attributes,the liquid metal current limiter(LMCL)is considered a new strategy for limiting short-circuit current in the power grid.A resistive wall liquid metal current limiter(RWLMCL)is designed to advance the starting current-limiting time.Experiments are performed to investigate the dynamic behaviors of liquid metal,and the influence of different currents on the liquid metal self-shrinkage effect is compared and analyzed.Furthermore,the liquid metal self-shrinkage effect is mathematically modeled,and the reason for the formation of arc plasma is obtained by simulation.The laws of arc plasma formation and the current transfer in the cavity are revealed,and the motion mechanisms are explained by physical principles.The simulations are in accordance with the test data.It is demonstrated that the sudden change of the current density at both ends of the wall causes the liquid metal to shrink and depress under the electromagnetic force,and the current starts to transfer from the liquid metal path to the wall resistance path.The RWLMCL can effectively advance the starting current-limiting time. 展开更多
关键词 resistive wall liquid metal current limiter(RWLMCL) liquid metal self-shrinkage effect arc plasma current transfer
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