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Impedance-based analysis of grid-connected inverter in high impedance grids
2013 IEEE 8th Conference on Industrial Electronics and Applications (ICIEA), 2013Distributed Generation may be located far away from load centers due to their use of new energy resource distribution characteristics. In this case, Long distance transmission lines will introduce an equivalent impedance to the grid. In this paper, the interaction between grid-connected inverter and high impedance grid is studied by means of impedance ...
null Xin Chen +3 more
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Grid Impedance Estimation with Oversampling for Grid-Connected Converters
2020 22nd European Conference on Power Electronics and Applications (EPE'20 ECCE Europe), 2020This paper presents a computationally simple estimation method of the grid impedance with the usage of a harmonic signal. To minimise the interference with the grid, an algorithm to define the start of the measurement is presented. Furthermore, oversampling of the current and voltage at the point of common coupling (PCC) is used to reduce the amplitude
Niklas Himker +2 more
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Impedance Scanning Method of Grid-tied Converters under Nonzero Grid Impedance Condition
2019 IEEE 10th International Symposium on Power Electronics for Distributed Generation Systems (PEDG), 2019The impedance of three-phase converters is widely used in stability analysis of grid-tied converters system. This paper investigates the frequency coupling effect on impedance scanning of converters in stationary reference frame under nonzero grid impedance condition.
Yuxin Zhang +5 more
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Quasi-Orthogonal Grids with Impedance Matching
SIAM Journal on Scientific Computing, 2000This paper presents a general elliptic grid generation system based on quasi-conformal mapping for arbitrary anisotropic regions. This system can be used to construct quasi-orthogonal smooth grids with an externally specified spacing normal to the boundaries of the domain.
Khamayseh, Ahmed, Hansen, Glen
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Impulse Impedance of Grounding Grids
IEEE Transactions on Power Apparatus and Systems, 1980A method and an empirical formula to calculate the inductance of square grounding grids fed at either centre or one of the corners is presented. Empirical formulae for the effective area and impulse coefficient for centre fed and corner fel square grids are determinel.
B.R. Gupta, B. Thapar
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Broadband methods for online grid impedance measurement
2013 IEEE Energy Conversion Congress and Exposition, 2013Grid impedance is an important parameter for the operation and control of grid-connected inverters used for the integration of solar, wind, and other distributed generation resources. Since the grid impedance usually varies over time and with grid operation conditions, online measurement is required for adaptive control of grid-connected inverters ...
Tomi Roinila, Matti Vilkko, Jian Sun
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Grid impedance identification considering the influence of coupling impedances
2010 IEEE International Symposium on Industrial Electronics, 2010In this paper the identification of grid connection points is analyzed. These points, also referred to as PCCs (Points of Common Coupling), are used to connect electrical equipment to the grid. The method described in this paper allows to set up a mathematical model for any PCC that reflects its behavior.
Hauke Langkowski +3 more
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Stability of grid-connected PV inverters with large grid impedance variation
2004 IEEE 35th Annual Power Electronics Specialists Conference (IEEE Cat. No.04CH37551), 2004Photovoltaic (PV) inverters used in dispersed power generation of houses in the range of 1-5 kW are currently available from several manufactures. However, large grid impedance variation is challenging the control and the grid filter design in terms of stability.
M. Liserre, R. Teodorescu, F. Blaabjerg
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2019 IEEE Energy Conversion Congress and Exposition (ECCE), 2019
When the impedance criterion is used to analyze the stability of the three-phase inverter-grid system, the impedance acquisition of the grid-connected inverter is particularly important. In the stationary reference frame, the equivalent admittance accurately characterizes the impedance characteristics of the inverter.
Junliang Liu +3 more
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When the impedance criterion is used to analyze the stability of the three-phase inverter-grid system, the impedance acquisition of the grid-connected inverter is particularly important. In the stationary reference frame, the equivalent admittance accurately characterizes the impedance characteristics of the inverter.
Junliang Liu +3 more
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Grid Impedance Impact Analysis of the Weak Grid-Tied VSC
2021 IEEE Green Technologies Conference (GreenTech), 2021The grid impedance is widely recognized as the key factor to the stability of the grid-tied power electronic devices. However, the influence of the grid impedance ratio is always neglected due to the assumption that grid reactance is much large than grid resistance.
Hong Hu +9 more
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