Computational electromagnetics

About: Computational electromagnetics is a research topic. Over the lifetime, 6412 publications have been published within this topic receiving 113727 citations. The topic is also known as: Electromagnetic field analysis.

The application of the conjugate gradient method for the solution of operator equations arising in electromagnetic scattering from wire antennas

Abstract: In this paper the method of conjugate gradient is presented for the solution of operator equations arising in electromagnetics. The particular problem to which the conjugate gradient method has been applied is the electromagnetic scattering from arbitrary oriented wire antennas. With this iterative technique, it is possible to solve electromagnetic problems involving electrically large structures without storing any matrices as is conventionally done in the method of moments. The basic difference between the proposed method and the matrix methods (Rayleigh-Ritz, Galerkin's, method of moments) for the same expansion functions is that for the iterative technique we are solving a least squares problem. Hence, as the order of the approximation is increased, the proposed technique guarantees a monotonic convergence for the residuals AI-Y, whereas matrix methods, in general, do not yield monotonic convergence. The conjugate gradient method converges for any initial guess; however, a good one may significantly lower the computation time. Also, explicit error formulas are given for the rate of convergence. Numerical results are presented for electromagnetic scattering from arbitrary oriented thin-wire antennas.

Detent Force Minimization of Permanent Magnet Linear Synchronous Machines Using Subdomain Analytical Method Considering Auxiliary Teeth Configuration

Abstract: This paper presents electromagnetic modeling and analysis of the detent force in a permanent magnet linear synchronous machine (PMLSM) according to auxiliary teeth configuration. Analytical solutions for magnetic fields generated by PMs are derived based on the Maxwell equation in terms of a 2-D Cartesian coordinate system. The magnetic vector potential of each subdomain (PM, air-gap, slot, and end region) is derived, and the field solution is obtained by applying the boundary and interface conditions between the subdomains. Based on the analytical solution, the magnetic force is derived by using the Maxwell stress tensor. All the analytical results were extensively validated using nonlinear finite-element analysis and experimental results. Using the proposed method, we investigated the influence of the machine parameters on the detent force. Therefore, the proposed method can be very useful in the initial design and optimization process of PMLSM for detent force analysis.

Comprehensive broadband electromagnetic modeling of on-chip interconnects with a surface discretization-based generalized PEEC model

Abstract: This paper proposes a comprehensive integral equation electromagnetic field solver for broadband modeling of on-chip interconnects. Instead of the computationally intensive volumetric discretization model, which appears to be currently the most popular method of choice for handling the tall and narrow cross sections of the on-chip wiring and capturing correctly the impact of adjacent wiring coupling and skin effect, the proposed generalized partial element equivalent circuit (PEEC) methodology utilizes a computationally more efficient conductor surface discretization. Key to the success of such a surface discretization model is the definition of a position- and frequency-dependent surface impedance used to relate the tangential electric field and current on the wire surface. A novel strategy for the identification of loops in the resulting discrete model leads to a numerically-stable and efficient mesh analysis-based PEEC formulation in support of on-chip interconnect electromagnetic modeling from DC to multi-GHz frequencies.

A quasi three-dimensional distributed electromagnetic model for complex power distribution networks

Abstract: This paper describes a systematic methodology for the electromagnetic modeling of complex power distribution networks. The proposed methodology uses locally three-dimensional (3D) modifications to an otherwise two-dimensional (2D) description of the behavior of electromagnetic fields between power/ground plane pairs, to model correctly the field behavior at discontinuities such as vias, pins, and splits in the power/ground plane structure. Furthermore, a systematic synthesis methodology is presented for the direct generation of a SPICE-compatible multiport macro-model for the power distribution network from its discrete quasi 3D model. The proposed modeling and equivalent circuit synthesis methodologies are validated through a specific numerical simulation study of the transient electromagnetic analysis of a power/ground plane pair during switching.

An integral equation approach for 2.5-dimensional forward and inverse electromagnetic scattering

Abstract: SUMMARY We present 2.5-D forward and inverse algorithms for modelling low-frequency electromagnetic scattering problems. These algorithms are intended to be used for interpretation of large-scale electromagnetic geophysical data. The algorithms are based on an integral equation approach. To solve the forward problem, a standard conjugate gradient normal residual method is employed, while the inverse problem is solved with the so-called multiplicative regularized contrast source inversion method. Inversion results with low-frequency electromagnetic data for single- and cross-well configurations are presented. Furthermore the advantages of combining the long-offset single-well and cross-well data are discussed.