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High-intensity focused ultrasound (HIFU) is increasingly getting in focus of interest for polymer layer joining (Liebler 2008). Previous studies investigated the heating effect in polymer materials induced by HIFU with liquid sound conductor (Bo Liu et al. 2013) and with solid sound conductor (Oehm et al. 2016). An improved understanding of the physical mechanisms of HIFU to heat thin polymer layers,...
In power electronics applications, high frequency models for cables are necessary to understand EMI issues in pulsewidth modulation drives. This paper shows the approach developed at the French Institute of Technology (IRT) Saint-Exupery, in order to take account of the frequency dependency of unshielded power cables per-unit-length parameters for EMC simulations. Fast, predictive models are compared...
An analysis method is studied for the amount and distribution of antenna mode current which is the source of radiation problems in the differential channels. By taking the nearby shield or real system ground into account, the multiconductor-transmission-line method can be applied and then the mode conversion from differential mode or common mode to antenna mode can be calculated. As validation, there...
In this study, RLCG method is used to estimate a low voltage transmission line for twisted overhead and underground low voltage distribution cables. This model is applied for cables with different types, different sections and lengths taking account the capacitive and the inductive coupling. SPICE determination of transmission characteristics and cables crosstalk are validated throughout physical...
This paper presents a computational tool intended to calculate and minimize the electric fields at ground level of High Surge Impedance Loading transmission lines. This type of transmission line achieves higher power transmission rates by utilizing optimized configuration for the phase conductors. This method is advantageous over other actions taken by the utility company such as increasing the maximum...
A tracing method is proposed in this paper to identify lines for outage for ice accumulation prevention on overhead lines during storms. The objective is to increase current flow on at-risk line by sequential outages of other lines in the network. The higher current flow causes more resistive power loss on line which increases temperature on the surface of the conductor. The outages are applied to...
Residential solar Photovoltaic (PV) installations are increasing at a very high pace in the United States. In 2017 there are approximately one million residential solar PV installations in the US. A significant share of these installations are downstream of distribution transformers and thus connected to the secondary. To precisely analyze voltage variations induced by PV systems into distribution...
Measurements have been conducted to show that glowing connections can occur in DC circuits at voltages as low as 12Vdc. Properties of glowing connections for dc circuit conditions for a variety of electrically conductive materials is presented. Results reveal glowing connection characteristics for commonly used conductor material found in electrical circuits (copper and steel) for 12V, 24V, and 48V...
The article presents the research results of the existing payment systems on urban passenger transport. The methodology for conducting a comparative analysis of travel payment systems has been proposed by authors. The criteria for their comparative evaluation has been formulated, the weight of each criterion has been determined for both groups of users. The rating of the payment systems has been determined...
This paper describes a method for a common transient analysis for the multi-circuit overhead transmission line. The presented algorithm is based on two-port approach, where the phase conductors and earth wires are modelled by inductive and capacitive coupled cascades of two-ports. For a considered network model, a system of ordinary differential equations (ODE) has been formulated and it has been...
This paper describes the calculation of the RLCG frequency-dependent parameters with the finite element method (FEM) for the computation of the fast transient overvoltages (FTOs). The proposed calculation intends to match the simulated results with the experimental measurements. It allows identifying the location of the dissipative effects and the contribution of each parameter. Numerical results...
The experiments and theoretical considerations about several cable configurations grounded at both ends are described. The theory of magnetic coupling and shielding is reviewed. In the experiment, a constant magnetic field is generated at 4 frequencies and 10 different cable configurations are tested at each frequency. 40 measurement results are presented and they are compared with 6 measurements...
Two-stage SC + Finite Difference (FD) procedures have been proposed since a long time to solve electrostatic and magnetostatic field plane problems in case of inhomogeneous dielectric materials. This had allowed to overcome accuracy problems caused by convex corners in the domain boundary and relevant field singularities, and to apply FD solvers in rectangular domains. In this paper, compound procedures...
This paper presents a methodology to increase the transmission lines (TLs) capacity and, simultaneously, decrease the intensity of electric field produced by its conductors in the ground level. A methodology for ascertaining whether Corona Loss is within acceptable limits is also developed. Such method aims to improve the performance of the TLs and it is based on analytical electromagnetic modeling...
Electrical equipment has to carry the rated normal current and short time withstand current. As shown in previous publications, the voltage-temperature relation allows calculating the temperature of contact elements and connectors for steady- state operating points. In the case of transient electric-thermal load, a finite-element analysis (FEA) is required to calculate the time-dependent distribution...
In this study, two wideband metasurfaces for LTE (Long Term Evolution) frequency applications has been proposed. The first design consists of two SRRs (split ring resonators) having gaps in opposite directions; and it has a S21 resonance at 3.7 GHz. The second design has identical SRRs; and it has a S21 resonance at 3.54 GHz. Both designs were realized via a CNC surface drilling tool. Fabricated SRR...
The ICP (inner corona protection) of the stator coil is to reduce the concentrated electric field at the corner and to release the electrical stress in the filler. With these functions the life of the coil can be extended and the tip-up values can be lowered. But the properties of itself such as resistivity and length (the distance between two high voltage touch points) also have influence on performances...
The paper presents the results of research that can be put into the development and research of non-contact rapid method for assessing the quality of the assembly and installation of EM designs. To achieve the objectives, studied the behavior of the mechanical connection of the contact pairs, namely the definition of the contribution of R, L, C parameters contact joints in the modulation level and...
The history of using the earth as an electrical conductor for man-made electricity for the past 270 years is detailed in this paper. In the beginning man-made electricity used the earth; the surface of the terrestrial ball we live on, as a conductor to return the continuous flowing electric current back to the source for 140 years. Edison realized that using the earth as an electrical conductor presented...
This paper presents in a unified way a set of hybrid methods, named FEM-BCI (Finite Element Method — Boundary Condition Iteration), already devised by the authors for the solution of electromagnetic problems, ranging from static and quasi static to dynamic ones, both for scalar and vector unknowns.
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