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故障限流器（FCL）；FCL阻抗；短路电流；故障电流；电力系统 1

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Adaptive simulation of wave propagation problems including dislocation sources and random media

Hassan YOUSEFI, Jamshid FARJOODI, Iradj MAHMOUDZADEH KANI

《结构与土木工程前沿（英文）》 2019年第13卷第5期页码 1054-1081 doi: 10.1007/s11709-019-0536-4

摘要： An adaptive Tikhonov regularization is integrated with an h-adaptive grid-based scheme for simulation of elastodynamic problems, involving seismic sources with discontinuous solutions and random media. The Tikhonov method is adapted by a newly-proposed detector based on the MINMOD limiters and the grids are adapted by the multiresolution analysis (MRA) via interpolation wavelets. Hence, both small and large magnitude physical waves are preserved by the adaptive estimations on non-uniform grids. Due to developing of non-dissipative spurious oscillations, numerical stability is guaranteed by the Tikhonov regularization acting as a post-processor on irregular grids. To preserve waves of small magnitudes, an adaptive regularization is utilized: using of smaller amount of smoothing for small magnitude waves. This adaptive smoothing guarantees also solution stability without over smoothing phenomenon in stochastic media. Proper distinguishing between noise and small physical waves are challenging due to existence of spurious oscillations in numerical simulations. This identification is performed in this study by the MINMOD limiter based algorithm. Finally, efficiency of the proposed concept is verified by: 1) three benchmarks of one-dimensional (1-D) wave propagation problems; 2) P-SV point sources and rupturing line-source including a bounded fault zone with stochastic material properties.

关键词： adaptive wavelet adaptive smoothing discontinuous solutions stochastic media spurious oscillations Tikhonov regularization minmod limiter

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一种改进的新型桥式固态限流器的研究

李洪凤,贾贵玺,齐炜,徐伟

《中国工程科学》 2005年第7卷第8期页码 75-79

摘要：

随着电网容量的不断扩大，短路电流限制技术已成为故障保护的一个研究热点。提出的新型桥式电路是在原有桥式拓扑结构上进行了改进，并提出了新的控制策略。详细介绍了新型桥式限流器的基本工作原理及特点，给出了基于Matlab/Simulink软件的仿真分析和基于天津大学动模实验室的实验结果。仿真与实验结果证明了所提出新型拓扑与控制策略的正确性。

关键词：短路限流器新型桥式电路 Matlab/Simulink仿真动模实验

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国产桥梁拉索用1 770 MPa 镀锌钢丝制造技术的研究

丁峰,桑春明,周代义,白柄东

《中国工程科学》 2009年第11卷第3期页码 57-64

摘要：

重点介绍了宝钢集团公司在苏通大桥斜拉索用高强度镀锌钢丝的研制实践中，通过制造技术研究和技术创新，形成了“双张紧 + 限径模”工艺、“主导工艺 + 微调”整体优化、“三度控制”热镀锌操作等三大关键技术，生产制造出了高强度、低松弛、具有良好扭转性能的国产桥梁斜拉索用高强度（1 770 MPa 级）镀锌钢丝。

关键词：镀锌钢丝扭转双张紧限径模沙砾抹拭

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电力系统中对称和/或不对称故障的限流器阻抗优化新方法 None

Mahmoud MODARESI, Hamid LESANI

《信息与电子工程前沿（英文）》 2018年第19卷第2期页码 297-307 doi: 10.1631/FITEE.1601689

摘要：为给电力网络设计者选择故障限流器（fault current limiters，FCLs）的阻抗类型和阻值，提出一种基于其在网络中的位置计算最佳FCL阻值的新方法。由于阻抗的复杂性，需同时考虑FCL阻抗实部和虚部的代价。FCL阻抗优化的目标函数，是以最小化代价最大限度减少故障电流。虽然最佳FCL阻抗值的计算受其在网络中位置的影响，但选取FCL位置的方法并非本文重点。该FCL阻抗优化方法可用于任何具有对称和/或不对称故障的网络。以一个14总线IEEE网络为例解释该过程。该网络采用的最优FCL阻抗是同时考虑FCL阻抗实部和虚部的大范围代价计算得到的。

关键词：故障限流器（FCL）；FCL阻抗；短路电流；故障电流；电力系统

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Series transformer based diode-bridge-type solid state fault current limiter

Amir HEIDARY,Hamid RADMANESH,Seyed Hamid FATHI,G. B. GHAREHPETIAN

《信息与电子工程前沿（英文）》 2015年第16卷第9期页码 769-784 doi: 10.1631/FITEE.1400428

摘要： We propose a novel series transformer based diode-bridge-type solid state fault current limiter (SSFCL). To control the fault current, a series RLC branch is connected to the secondary side of an isolation series transformer. Based on this RLC branch, two current limiting modes are created. In the first mode, R and C are bypassed via a paralleled power electronic switch (insulated-gate bipolar transistor, IGBT) and L remains connected to the secondary side of the transformer as a DC reactor. In the second mode, the series reactor impedance is not enough to limit the fault current. In this case, the fault current can be controlled by selecting a proper on-off duration of the parallel IGBT, across the series damping resistor ( ) and capacitor, which inserts high impedance into the line to limit the fault current. Then, by controlling the magnitude of the DC reactor current, the fault current is reduced and the voltage of the point of common coupling (PCC) is kept at an acceptable level. In addition, in the new SSFCL, the series RC branch, connected in parallel with the IGBT, serves as a snubber circuit for decreasing the transient recovery voltage (TRV) of the IGBT during on-off states. Therefore, the power quality indices can be improved. The measurement results of a built prototype are presented to support the simulation and theoretical studies. The proposed SSFCL can limit the fault current without any delay and successfully smooth the fault current waveform.

关键词： Solid state fault current limiter (SSFCL) Power quality Voltage sag Point of common coupling (PCC) Isolation transformer