Results 31 to 40 of about 123,509 (118)

An Impedance Model for Angle-Dependent Sound Reflection and Absorption with Diffraction Effects

Acoustics
Traditionally, an open window is considered a kind of reference for perfect sound absorption. The sound reflection and absorption of an aperture is analyzed by means of an impedance model representing a rectangular absorbing surface surrounded by a thin,
Jens Holger Rindel
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A programmable frequency scan algorithm based on harmonic balance

iEnergy
This paper presents a programmable frequency scan algorithm based on harmonic balance. The core idea involves treating systems under perturbation as nonlinear time-periodic (NTP) systems.
Lu Miao, Wenyan Jia, Jinchang Chen, Yang Yi, Shun Li, Qirong Jiang, Chongbin Zhao   +6 more
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Hybrid Impedance-Based Controller Design of Grid-Connected Converter for Whole-System Stabilization of Grid-Connected DC Microgrids

IEEE Access
The grid-connected converter (GCC) in a grid-connected DC microgrid performs an important role in stabilising the interaction of the AC and DC sections.
Yuxin Zhu, Fei Wang, Zhengyu Lin, James Fleming   +3 more
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Robot Variable Impedance Skill Transfer and Learning Framework Based on a Simplified Human Arm Impedance Model

IEEE Access, 2020
A variable impedance skill transfer framework is introduced and experimentally evaluated in this article. This framework mainly includes the following: 1.
Rui Wu, He Zhang, Jie Zhao
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High-frequency Resonance Analysis and Impedance Reshaping Control of MMC-HVDC System Based on Frequency Coupling Impedance Model

Journal of Modern Power Systems and Clean Energy
In recent years, high-frequency resonance (HFR) events occurred in several modular multilevel converter based high-voltage direct current (MMC-HVDC) projects. The time delay of an MMC-HVDC system is the critical factor that induces HFR.
Juanjuan Wang, Wei Chen, Yuekun Liu, Chuang Fu, Yunming Ye, Junjie Feng   +5 more
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Impedance Aggregation Method of Multiple Wind Turbines and Accuracy Analysis

Energies, 2019
The sequence domain impedance modeling of wind turbines (WTs) has been widely used in the stability analysis between WTs and weak grids with high line impedance.
Liang Chen, Heng Nian, Yunyang Xu
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Impedance Modelling and Parametric Sensitivity of a VSC-HVDC System: New Insights on Resonances and Interactions

Energies, 2018
Pervasiveness of power converters in the electric power system is expected in the future. Such large penetration will change the current power system dynamics leading to uncertain, unexpected, and potentially critical responses.
Adedotun J. Agbemuko, José Luis Domínguez-García, Eduardo Prieto-Araujo, Oriol Gomis-Bellmunt   +3 more
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Impedance Modeling and Stability Analysis for Cascade System of Three-Phase PWM Rectifier and LLC Resonant Converter

Energies, 2018
In this paper; the impedance model of PWM rectifier and LLC resonant converter are deduced, and the stability analysis of cascade system is studied. The principle of three-phase PWM rectifier is introduced; and the small signal model in d-q coordinate ...
Rutian Wang, Yuyang Wu, Guoqing He, Ying Lv, Jiaxing Du, Yanhao Li   +5 more
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Generalized MIMO Sequence Impedance Modeling and Stability Analysis of MMC-HVDC With Wind Farm Considering Frequency Couplings

IEEE Access, 2020
Recently, small-signal stability of the modular multilevel converter (MMC) based high-voltage direct current (HVDC) transmission for wind farm integration has attracted great attentions.
Haoxiang Zong, Chen Zhang, Jing Lyu, Xu Cai, Marta Molinas, Fangquan Rao   +5 more
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Research on a z-domain impedance criterion for wideband oscillation of the VSC-HVDC transmission system

Zhejiang dianli
To delve into the mechanism behind wideband oscillation instability in voltage source converter based high voltage direct current （VSC-HVDC） transmission system and swiftly assess system stability with precision， a modeling method and a stability ...
ZHANG Yijing, DING Haoyin, SHI Yanqiang, HUANG Zhiguang, ZHONG Weilun, XU Bo   +5 more
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