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Showing 1 to 20 of 24 for “"impedance matrix"”.
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Análise de estabilidade para inversores LCL conectados à rede elétrica baseada em expressões analíticas e estimativas de impedâncias no domínio síncrono DQ
The diversification in the energy matrix has been driving the emergence of new forms of electricity generation, often integrated into the grid through the inverter. The control of this device is usually designed without considering the impact of the connection with the grid. One approach to assess …
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Numerical methods for frequency dependent line parameters with applications to microstrip lines and pipe-type cables
… frequency). For the subconductors system, an impedance matrix is then built using Ohm's law and the concept of Geometric Mean Distances (GMD). Secondly, the current distributions in the subconductors are solved from the telegrapher's equations. Thirdly, a linear current distribution is …
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Scalable Acceleration of The Characteristic Mode Analysis Computational Toolbox Using Big Data Techniques
… by analyzing its Method of Moments (MoM) complex impedance matrix at every frequency. Depending on the size or the complexity of the target, its MoM impedance matrix can be large, containing tens of thousands of rows and columns. Therefore if hundreds of frequencies are needed to accurately …
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Power system analysis on programmable calculators
… system performance equations by either the bus impedance matrix approach or the bus admittance matrix approach. Also attention is focused on the solution of the machine swing equations by the state transition method and by the technique of fourth-order Runge-Kutta. Comparisons are made between …
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Applications of load flow by hybrid computer
… and accuracy. An algorithm for determining the impedance matrix of the power system network was developed using the hybrid computer. When implemented, it proved helpful in improving the accuracy of the hybrid load flow. Application of the hybrid computer for use in an optimal load flow problem …
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Tensorial Impedance Surfaces for Manipulating Microwaves
… conditions are often described with a "surface impedance". Tensorial impedance metasurfaces are surfaces where, due to anisotropy, the impedance becomes a 2nd rank tensor. This results in a boundary condition that has greater control over the surface fields than scalar impedance boundaries. Most …
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Characterization of a Phased Array Feed Model
… and measured element receive patterns, array impedance matrix, signal and noise correlation matrices, and efficiencies and sensitivities of the PAF are compared and promising levels of agreement are shown. Modeled sensitivity is 30 to 46% larger than measured.</p>
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Statistical Modeling of Wave Chaotic Transport and Tunneling
… area concerns the statistical properties of the impedance matrix (related to the scattering matrix) describing the input/output properties of waves in cavities in which ray trajectories that are regular and chaotic coexist (i.e., `mixed' systems). The impedance can be written as a summation over …
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Energy storage in reconfigurable antennas
… available from typical antenna measurements like impedance, or from conventional computational techniques such as the electric field integral equation. This work describes a parallel-computing optimized method of moments code that can be used to obtain the classic method of moments impedance …
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Switching mode power supply noise source impedance measurement and EMI filter characterization
… of an EMI filter is closely related to the impedance of the noise source. Due to the time-varying nature of the noise source impedance of an offline power supply, the measurement of it cannot be done using conventional impedance measuring methods. Two new methods, the insertion loss method …
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Design, modelling and implementation of antennas using electromagnetic bandgap material and defected ground planes
… antenna arrays on EBG was developed. Here the impedance matrix resulting from the meshing analysis is manipulated by the GA process in order to find the optimal antenna and EBG operated at 2.4 GHz with the goal of targeting a specific fitness function. Furthermore, an investigation of GA on 2×2 …
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Analyzing modal decomposition data of finite antenna arrays
… radiation patterns and cause large variations in impedance across the array elements. These effects can be partially mitigated through conditioning certain elements of the array, or adding terminated “dummy” elements to the array. These methods often require many iterations of simulation and can …
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Impedance-Based Stability Analysis in Power Systems with Multiple STATCOMs in Proximity
… problem is induced by STATCOMs, d-q frame impedance-based stability analysis was used, for the first time, to explore the inherent power system instability problem with presence of STATCOMs as it provides an accurate understanding of the root cause of instability within the STATCOM control …
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Power transformer magnetization under GIC/GMD
… traverses for dc excitation are presented. Impedance matrix entries of a single phase transformer are compared for normal and dc operations. New observations have been formed based on the simulation results. The study helps to reveal the fundamental transformer magnetization mechanism under …
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Synchrophasor Sensing and Processing Based Smart Grid Security Assessment for Renewable Energy Integration
… systems with a wind power plant connected. The impedance matrix can be calculated by the voltage and current information collected by the PMUs. Based on the impedance matrix, locations in SG can be identified, where cause the greatest impact on the voltage at the wind power plants point of …
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DIRECT VOLTAGE MEASUREMENTS USING BULK ACOUSTIC WAVES IN LiNbO3
… breakdown limitations in materials, parasitic impedance effects that can distort the pulse shape, and pickup of extraneous signals resulting from electromagnetic interference effects. A piezoelectric crystal-based bulk acoustic wave sensor using lithium niobate (LiNbO3) that has applications to …
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Frequency dependent impedance of stranded conductors using the subdivision method
… and inductances are placed into a complex impedance matrix which is then reduced through mathematical manipulations to obtain a single complex number that represents the equivalent resistance and inductance of the whole conductor. The advantage of this method is that it automatically …
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A Hybrid Approach for Nonlinear Soil-Structure Interaction Analysis of Pile- Supported Bridges
… In the substructure modelling, complex-valued impedance functions are used to represent stiffness and energy dissipation characteristics of soil-pile interaction system. While characteristics of the pile head impedance functions have been decently determined for linear soil-pile interaction, …
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A Study of Techniques to Solve the Disparate Mesh Size Problem With an Application to Sinuous Antennas
… produces an ill-conditioned method of moments impedance matrix. Since the FMM algorithm relies on iterative solvers to solve the matrix equation, the fast in FMM becomes a misnomer if the iterative solver converges very slowly or not at all. The sinuous antenna embodies the disparate mesh size …
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Heterogeneous (HG) Blankets for Improved Aircraft Interior Noise Reduction
… was developed and experimentally validated using impedance and mobility methods (IMM). A novel impedance matrix formulation for the HG blanket is derived and coupled to the DPS using an assembled matrix approach derived from the IMM. Genetic algorithms coupled with the previously described design …
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