Saša S. Ilić

Hybrid Boundary Element Method for Multi-Layer Electrostatic and Magnetostatic Problems

Abstract A hybrid numerical method is proposed involving a successful combination of the equivalent electrodes and boundary element method. Electric field and electric potential distribution are determined by using both equivalent electrodes and equivalent charges. Greens function for potential of the charge per unit length, placed in free space, on the boundary of two dielectrics, is used. Magnetic-field distribution is determined by applying equivalent currents through magnetic vector potential and substitution of Amperes microscopic currents with total currents. The accuracy of the developed method is highlighted with some simple numerical examples.

Equivalent Electrode Method Application on Anisotropic Micro Strip Lines Calculations

Theoretical analysis of a micro strip line, assuming TEM mode propagation is carried out in the paper. Micro strip lines are significant parts of multi-layer integrated circuits. Electric field and electric potential distribution, effective dielectric permittivity and characteristic impedance of transmission line are determined applying equivalent electrodes method (EEM). The Greens function of the uniform charge per unit line length is used, placed in free space, above both an anisotropic medium and grounded plate. Due to combination of numerical and analytical determination, this is a hybrid method.

Hybrid Boundary Element Method and Quasi-TEM Analysis of Two-Dimensional Transmission Lines—Generalization

Abstract The hybrid boundary element method, based on the equivalent electrodes method and the boundary element method, is presented in this article. This method is applied on several examples for calculating the characteristic impedance of transmission lines. It should be emphasized that the combination of the equivalent electrodes method and a new variant of the boundary element method can be efficiently implemented in quasi-transverse electromagnetic analysis of transmission lines without loss of accuracy. All results for the characteristic impedance of the observed transmission lines are compared to corresponding ones obtained by the finite-element method.

A Novel Approach to the Positive DC Nonlinear Corona Design

Abstract This article is aimed at proposing one very simple method for electric field and potential distribution determination in the case of large charges at electrodes surfaces when the electric field takes a very high value and induces corona discharges. The method also enables capacitance calculation as well as a dimension of the corona region. By using appropriate analogies, parameters of grounding systems driven by high currents can also be determined.

Interaction magnetic force calculation of radial passive magnetic bearing using magnetization charges and discretization technique

Calculation of the interaction magnetic force between two ring permanent magnets with radial magnetization is presented in the paper. Such configuration corresponds to a radial passive magnetic bearing. The simple and fast analytical approach is used for this calculation based on magnetization charges and discretization technique. The results for interaction magnetic force obtained using proposed approach are compared with finite element method (FEM). The advantage of presented approach is its simplicity and time efficiency since only complete elliptic integrals of the second kind are used and other additional integrations are avoided in this calculation.

Interaction Magnetic Force Calculation of Ring Permanent Magnets Using Ampere's Microscopic Surface Currents and Discretization Technique

Abstract Calculation of the interaction magnetic force between two ring permanent magnets of trapezoidal cross-section and a ring permanent magnet above the infinite linear magnetic plane is presented in this article. The simple and fast analytical approach is used for these calculations based on the distribution of microscopic surface Amperes currents and the discretization technique. The results for the interaction magnetic force obtained using the analytical method and discretization technique are compared with the finite-element method by using FEMM 4.2 software (Meeker, n.d.).

Interaction Magnetic Force Calculation of Permanent Magnets Using Magnetization Charges and Discretization Technique

Abstract This research includes a simple and fast semi-analytical approach for magnetic interaction force calculations based on fictitious magnetization charges and the discretization technique. Two different examples are analyzed: (1) calculation of the interaction magnetic force between laterally displaced cylindrical permanent magnets made of the same magnetic material and magnetized uniformly along their axes of symmetry (opposite direction) and (2) determination of the attraction force between a “horseshoe” permanent magnet of circular cross-section and an infinite linear magnetic plane with relative magnetic permeability μr. The results for the interaction magnetic force obtained by the proposed approach are compared with the finite-element method.

TEM analysis of multilayered transmission lines using new hybrid boundary element method

Theoretical analysis of multilayered transmission lines assuming TEM propagation mode is carried out in the paper. Effective dielectric permittivity and characteristic impedance of the transmission line are determined applying the new hybrid boundary element method (HBEM) based on the equivalent electrodes method (EEM). All results are compared with the exact analytical, or the finite element method (FEM) solutions.

Total Effective Height and Atmospheric Potential Distribution in the Vicinity of Buildings with Lightning Protection Rods

Abstract Atmospheric potential distribution in the vicinity of buildings with a lightning protection rod, with and without a horizontal circular loop, is determined in this article. The effective height of the building with a lightning protection rod (an important parameter for defining the protection area) is also determined.

Analysis of shielded coupled microstrip line with partial dielectric support

A shielded coupled microstrip line with partial dielectric support is analysed using the hybrid boundary element method (HBEM) and the finite difference method (FDM). The HBEM is a combination of the equivalent electrodes method (EEM) and the boundary element method (BEM). The microstrip line characteristic parameters: the effective relative permittivity and the characteristic impedance are determined. “Odd” and “even” modes are taken into account. The results are compared with corresponding ones found in the literature.