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Considering the influence of wires sag, towers, up-and-downs on the ground, surrounding buildings and other situations, the ionized field under HVDC transmission lines is actually a 3-D field and its calculation method is necessary to be found. In this paper, a method to calculate the 3-D ionized field was proposed to be based on the Deutsch assumption. After the validity of the method is testified,...
This paper describes a meshless approach to obtain accurate solutions for propagating microwave problems. The Meshless Local Petrov-Galerkin (MLPG) method, with the Heaviside step test functions and Radial basis point interpolation method (RPIM) shape functions, is used. Results are obtained for a two-dimensional model and are compared with a consolidated Finite Element Method (FEM).
Two-port TEM cells with rectangular cross-section are commonly used to produce plane electromagnetic waves with high electric field. The non-uniformity of the system makes the use of numerical methods extremely useful in the design phase in order to achieve a very good behavior of the TEM cell over a wide frequency range of operation. In this paper an extended version of PEEC is used to study a real...
A fast method has been proposed for calculating the shielding current density in a high-TC superconductor. An initial-boundary-value problem of the shielding current density cannot be always solved with the Runge-Kutta method even when an adaptive step-size control algorithm is incorporated. In order to overcome these difficulties, the J-E constitutive relation is deformed so that the resulting solution...
This paper presents a model for calculating electric field in non conducting regions in steady state AC magnetic application, with conductors described by surface impedance, using the 3D finite element method. This approach is validated by calculating the equivalent impedance of a coil comparing the presented surface impedance decoupled method with a volume decoupled method.
A new force expression of dielectrics subjected to electric field is proposed in this paper. It is the electric version corresponding to the equivalent magnetizing current method. It was conjectured by electromagnetic duality. Numerical result shows that it has a good agreement with the conventional methods.
In this paper, we present a multiobjective evolutionary approach to design a microwave heating applicator. The goal for the device is to heat the maximum amount of water spending minimum energy. A set of optimal solutions is obtained, the Pareto front. A decision-making strategy was applied for selecting the point that corresponds to the most efficient device. The efficiency is improved by using a...
An improved method based on the charge simulation method is used to predict the corona onset voltage and electric field after space charges are calculated based on the streamer model. Because of the existence of space charges the corona onset electric field is changed a little, which will have a little effect on the analysis of corona phenomena. The corona onset electric field is given especially...
In this paper, the simulation and optimization electric field distribution in 550kV disconnectors of Gas Insulated Switchgear (GIS) are investigated employing the Finite Element Method (FEM) and Response Surface Method (RSM). The simulation results reveal that a uniform electric field distribution is achieved in 550kV disconnectors of GIS. This optimal prototype of disconnectors has been undertaken...
Summary form of only given: We present here an original method of computing the magnetic induction in a conductor thanks to a post-processing from the Boundary Elements Method (BEM). This general formulation is then applied to the case of underwater electric systems under cathodic protection.
A fast three-dimensional (3D) ground penetrating radar (GPR) forward and inverse scattering method is presented based on the diagonal tensor approximation (DTA). For the forward scattering problem, the first iteration about the frequency-dependent scattering coefficients in the DTA is used. By further evaluating the scattering tensor at the GPR center frequency to remove its frequency dependence,...
An inversion methodology for microwave imaging based on an improved tabu search algorithm and frequency-domain finite element method is proposed. Numerical results are reported to reaffirm positively its feasibilities and advantages.
The response of lightning impulse voltage was explored in dielectric liquids employing the hydrodynamic modeling with three charge carriers by using the finite element method. To understand the physical behaviors of discharge phenomena in dielectric liquids, the response of step voltage has been extensively studied recently by using numerical techniques, but that of lightning impulse voltage was rarely...
The Partial Element Equivalent Circuit method (PEEC) is well suited to the extraction of the conducted electromagnetic (EM) disturbance parameters in the electronic wiring systems. It can be an efficient tool for the EMC study relevant to automotive cables. However, the complete EMC analysis of embedded systems requires also reliable models for the radiated emissions especially at high frequencies...
Based on the modified image theory, the FDIE of a thin wire placed at arbitrary direction in lossy half-space is built, and the corresponding TDIE is obtained by the inverse Fourier transformation. The transient currents induced on the wire are calculated by the time domain MoM combined with MOT. It is shown, compared with reference, the method herein is effective and the conductivity of the soil...
A hybrid 2D/3D numerical method is introduced to solve the ion flow field around a house near bipolar high voltage direct current (HVDC) transmission lines. At first, a 2D upwind finite element algorithm for the computation on the ion flow field near bipolar line structure is set up. Then a 3D method is used to analyze the ion flow field in the vicinity of a house under the HVDC lines. The 2D results...
A state space finite element method is presented for the calculation of transient electric field in oil-immersed insulation system of converter transformer. Firstly, the state equation is derived based on the quasi-static electric field theory, combined with the given boundary value using the penalty method, which has a clear physical meaning. Secondly, the state equation is solved in a fine integration...
This paper presents an optimum design of a glass net for mold transformer to reduce the electric field. The glass net is used to prevent the coil and epoxy resin, but it causes the electric field intensity and partial discharge. The optimum design of a glass net has been investigated by mean of response surface method and finite element method.
This paper compares the hybrid FEM-BEM and FEM-DBCI methods for the solution of open-boundary electrostatic field problems. Both methods couple a differential equation for the interior problem with an integral equation for the exterior one. The comparison shows that FEM-BEM is more accurate than FEM-DBCI but requires more computing time.
(μ+λ) Evolution Strategy(ES), based on electrostatic calculation, is suggested for improving the insulation performance of Vacuum Interrupter(VI). Axi-symmetric finite element routine including floating boundary condition for floating shields is applied to analyze electric potential and field distribution in VI. Three design variables of two types of multi-shield are selected for minimizing the maximum...
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