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Article

Chien-Yi Huang and Ching-Hsiang Chen

Differing from previous studies trying to solve the electromagnetic compatibility (EMC) issue by addressing single factor, this study aims to combine measures of…

Abstract

Purpose

Differing from previous studies trying to solve the electromagnetic compatibility (EMC) issue by addressing single factor, this study aims to combine measures of shielding, filtering and grounding to design parameters with the Taguchi method at the beginning of product design to come up with the optimal parameter combination.

Design/methodology/approach

EMC-related performance such as radiated emission, conduction interference and electrical fast transient/burst immunity (EFT) are response variables, whereas the printed circuit board and mechanic design-relevant parameters are considered as control factors. The noise factors are peripherals used together with the tablet.

Findings

The optimal design parameter matrix based on results from the application and integration of multivariate analysis method of principal component grey relation and technique for order preference by similarity to ideal solution suggests 14 grounding screw holes, cooling aperture of casing at diameter of 3 mm and staggered layout and 300O filter located at source of noise. Validation of this matrix shows around 10, 1 and 8 per cent improvement in radiation, conduction interference and EFT immunity.

Originality/value

The multivariate quality parameters’ design method proposed by this study improves EMC characteristics of products and meets the design specification required by customer, accelerating electronic product research and development process and complying with electromagnetic interference test regulations set forth by individual country.

Details

Microelectronics International, vol. 34 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

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Article

Matthew Sibanda and Robert Ryk van Zyl

Incorporating electromagnetic compatibility (EMC) in the design life of traditional satellites is entrenched in the satellite industry. However, EMC treatment of CubeSats…

Abstract

Purpose

Incorporating electromagnetic compatibility (EMC) in the design life of traditional satellites is entrenched in the satellite industry. However, EMC treatment of CubeSats has not been widely pursued, for various possible reasons. CubeSats are a young technology platform initially intended for students and researchers at universities to create awareness and excitement amongst them for space technology. This and other factors limited the need for stringent EMC planning. As CubeSats mature in complexity, the success of future missions will rely on incorporating proper EMC designs in their development. This paper aims to address the experimental investigation of known EMC culprits within a CubeSat’s context.

Design/methodology/approach

Electromagnetic interference suppression effectiveness of cable trays in CubeSats, as well as crosstalk in high-speed/frequency data links, is investigated, using the PC/104 connector stack. Some recommendations for improving the EMC and, therefore, enhancing satellite mission success are provided.

Findings

It was found that, if physically feasible in the CubeSat, cable trays are significant radiation suppressors. A further investigation into crosstalk between pins of the PC/104 connector stack showed that grounding a pin in between two signal pins leads to a significant reduction in the coupled signal.

Originality/value

This paper addresses EMC within the context of a CubeSat and outlines experiments done resulting in cost-effective methods of reducing interference by using already available material (such as unused signal pins available in the PC/104 connector).

Details

Journal of Engineering, Design and Technology, vol. 14 no. 4
Type: Research Article
ISSN: 1726-0531

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Article

Seyed Sajad Sajadi, Saeed Reza Ostadzadeh and Seyed Hossein Hesamedin Sadeghi

The purpose of this paper is to investigate the simultaneous effects of ionization and dispersion of soil on the impulse behavior of grounding electrodes under first and…

Abstract

Purpose

The purpose of this paper is to investigate the simultaneous effects of ionization and dispersion of soil on the impulse behavior of grounding electrodes under first and subsequent stroke currents.

Design/methodology/approach

A recently introduced technique called improved multi-conductor transmission line (MTL) is simplified for grounding electrodes buried in both-affected soils.

Findings

The simulation results show that including the two effects simultaneously in highly resistive soils under high-valued subsequent stroke current is recommended. Otherwise, simultaneous effects can be disregard.

Originality/value

To the best of the authors’ knowledge, there is no research on sensitivity analyses for the simultaneous inclusion of the two effects on the effective length and the induced voltage on the soil surface. To this end, the simplified MTL is applied to the grounding electrodes. The simulation results show that the computational efficiency in comparison with previous methods is, first, considerably increased. Second, the simultaneous effects result in decreasing the soil surface voltage with respect to situations where either ionization or dispersion is taken into account (single-affected soils). In other words, the performance of grounding systems is improved. Third, the effective length in both-affected soil is has a middle value with respect to the single-affected soil. Such findings practically and financially are of importance.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 39 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

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Article

Nebojsa B. Raicevic and Nikola Raicevic

Underground cables can produce higher electromagnetic fields directly above them than an overhead line. The majority of cable failures on distribution system are caused by…

Abstract

Purpose

Underground cables can produce higher electromagnetic fields directly above them than an overhead line. The majority of cable failures on distribution system are caused by defects in the cable accessories. Nowadays, significant research has been carried out worldwide into examining whether electricity, and in particular, the presence of electric and magnetic fields have an adverse impact on health, especially the occurrence of cancer and childhood leukemia. The purpose of this paper is to optimize the electric field distribution in underground cable accessories. This reduces the impact of the harmful effects of the fields on living beings and humans.

Design/methodology/approach

Cable terminations and joints are designed to eliminate the stress concentration at the termination screen to avoid the breakdown of the cable and high values of electric field at these points. Any improvement in the cable termination and joints construction is of great interest. There are several methods for the solution of electric field distribution. These can be summarized as analytical, experimental, free-hand field mapping, analogue methods and numerical methods. In this paper cable accessories are modeled by using multilayer dielectric system and very thin deflector’s cones.

Findings

This model includes specific insulators design and smart choice of electrodes position. Stress-grading nonlinear materials in form of tapes and tubes were used with much success. In order to optimize the cable joint parameters, two criteria were monitored – total electric field magnitude and magnitude of the tangential component. More than 30 percent is reduced impact of cables on the environment.

Originality/value

In order to investigate the accuracy of the applied numerical model, various configurations of the cable accessories are studied. The first time is applied new Hybrid Boundary Elements Method on the protection of the environment.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 34 no. 4
Type: Research Article
ISSN: 0332-1649

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Article

N. Vidal, J.M. Lopez‐Villegas and J. Sieiro

The purpose of this paper is to study the interaction of electromagnetic fields with biological tissues in the presence of antennas implanted subcutaneously for…

Abstract

Purpose

The purpose of this paper is to study the interaction of electromagnetic fields with biological tissues in the presence of antennas implanted subcutaneously for biotelemetry applications. The authors examined the influence of these radiative devices on energy absorption and also their effects as reflective metal surfaces when incoming radiofrequency energy was present.

Design/methodology/approach

The research was carried out using electromagnetic modeling based on the finite difference time domain method and the calculations were performed to determine the electric field and specific absorption rate. The implanted antenna operated in the Medical Implant Communication Service band. The incoming external electric fields considered included different frequency bands covering most current telecommunications standards.

Findings

Levels of absorbed energy with and without the implanted device.

Practical implications

The paper offers an analysis of results and comparison with current dosimetric standards and guidelines for limiting electromagnetic exposure.

Originality/value

The paper studies the interactions of implanted antennas with biological tissues, taking into account two behaviors: radiative and passive.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 31 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

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Article

Ping-Ping Ding, Lionel Pichon, Laurent Bernard and Adel Razek

The purpose of this paper is to calculate the induced electromagnetic fields in human body exposed to the wireless inductive charging system of electric vehicles has been…

Abstract

Purpose

The purpose of this paper is to calculate the induced electromagnetic fields in human body exposed to the wireless inductive charging system of electric vehicles has been conducted based on the numerical simulation.

Design/methodology/approach

A homogeneous human body model is built and a representative wireless inductive charging system is used for the exposure assessment. The numerical simulation relies on finite element method with formulations in terms of the magnetic vector potential. The electromagnetic fields in terms of magnetic flux density and electric field are computed in the human body and compared with the electromagnetic exposure limits.

Findings

It has been found that the induced EMFs in the near-field exposure configuration greatly comply with the safety guidelines.

Originality/value

This study could help the development of the wireless inductive charging system with meeting the safety standard of radiation protection.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 34 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

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Article

Kehinde Ogunyanda, Wilfred Fritz and Robert van Zyl

This paper aims to report the modelling and simulation work that predicts the behaviours of both a Josephson junction (JJ) and a dc superconducting quantum interference…

Abstract

Purpose

This paper aims to report the modelling and simulation work that predicts the behaviours of both a Josephson junction (JJ) and a dc superconducting quantum interference device (SQUID). It is pertinent to predict the SQUID magnetometers’ behaviours via simulations, before subjecting them to real experiments because they are quite expensive to acquire, and can be easily damaged during test analysis.

Design/methodology/approach

To achieve this, power simulation (PSIM) was used to model and simulate a JJ, using the basic equation that describes the effective current through it. A dc SQUID magnetometer, which is composed of two JJs, was then modelled and simulated using the modelled JJ. Thermal noise simulation is also included, to observe its effects on the magnetometer’s output. A directly coupled flux-locked loop circuit was later included in the simulation to amplify and linearise the SQUID’s output, which is usually sinusoidal.

Findings

When steady bias currents were applied to the JJ, the resulting voltage across it was seen to oscillate. The JJ’s and SQUID’s voltage–current characteristics, and voltage–flux characteristics were also observed in the simulations, and the results respectively agree with the behaviours of a typical JJ and dc SQUID magnetometer.

Originality/value

A way of simulating SQUIDs, without a superconducting simulation tool, is presented. The work provides a much simpler way of studying the behaviour of dc SQUID magnetometers, due to the easy accessibility and fast simulation capability of the software used, with an added advantage of being able to simulate the thermal noise effects, without having to import this facility from secondary software.

Details

Journal of Engineering, Design and Technology, vol. 13 no. 2
Type: Research Article
ISSN: 1726-0531

Keywords

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Article

Andrea G. Chiariello, Carlo Forestiere, Giovanni Miano and Antonio Maffucci

Nowadays, nano-antennas or nanoscale absorbers made by innovative materials such as carbon nanotubes are gaining more and more interest, because of their outstanding…

Abstract

Purpose

Nowadays, nano-antennas or nanoscale absorbers made by innovative materials such as carbon nanotubes are gaining more and more interest, because of their outstanding features. The purpose of this paper is to investigate the scattering properties of carbon nanotubes, either isolated or arranged in arrays. The peculiar behaviour of such innovative materials is studied, taking also into account the finite length of the structure and the dependence of the scattering field from the operating temperature.

Design/methodology/approach

First a model is presented for the electrical transport along the carbon nanotubes, based on Boltzmann quasi-classical transport theory. The model includes quantistic and inertial phenomena observed in the carbon nanotube electrodynamics. The model also includes the effects of temperature. Using this electrodynamical model, the electromagnetic formulation of the scattering problem is cast in terms of a Pocklington-like equation. The numerical solution is obtained by means of the Galerkin method, with special care in handling the logarithmic singularity of the kernel. Case studies are carried out, either referred to isolated single-wall carbon nanotubes (SWCNTs) and array of SWCNTs.

Findings

The scattering properties of SWCNT are strongly influenced by the temperature and by the distance between the tubes. As temperature increases, the amplitude of the resonance peaks decreases, at a rate which is double the rate of changes of temperature. The resonance frequencies are insensitive to temperature. As for the distance between the tubes in an array, it influence the scattering resonance introducing a shift in the resonance frequencies which is appreciable for distances lower than the semi-length of the CNT. For higher distances the CNT scattered field may be regarded as the sum of the fields emitted by each CNT, as if they were isolated.

Research limitations/implications

As far as now only SWCNTs have been studied. The multi-wall carbon nanotubes would show a richer behaviour with temperature, due to the joint effect of reduction of the mean free path and increase of the number of conducting channels, as temperature increases.

Practical implications

Possible use of carbon nanotubes as absorbing material or scatterers.

Originality/value

The model presented here is based on a self-consistent and physically meaningful description of the CNT electrodynamics, which takes rigorously into account the effect of temperature, size and chirality of each CNT.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 32 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

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Article

Vesna Arnautovski‐Toševa, Khalil El Khamlichi Drissi and Kamal Kerroum

The purpose of this paper is to present a frequency domain analysis of high frequency behaviour of an indoor Powerline communications (PLC) circuit in the presence of a…

Abstract

Purpose

The purpose of this paper is to present a frequency domain analysis of high frequency behaviour of an indoor Powerline communications (PLC) circuit in the presence of a plaster board/concrete wall structure. The main purpose of this analysis is to investigate the influence of the wall structure on the current distribution and the radiated electric field due to PLC signals in range from 3 MHz to 30 MHz.

Design/methodology/approach

The mathematical model is based on the full‐wave theory formulated by the Mixed Potential Integral Equation (MPIE) for the electric field due to energized thin‐wire conductors in stratified media. The solution for the current and the electric field distribution is obtained by using the Method of Moments.

Findings

Numerical results are obtained of the current distribution along the conductors of the PLC circuit and the radiated electric field in presence of a wall structure. Two cases are analyzed: when the circuitry is placed in the wall; and when the circuitry is placed outside the wall.

Practical implications

The paper presents the mathematical model that may be applied for analysis of indoor PLC circuits placed in presence of wall structures.

Originality/value

In the paper, a full‐wave model of the PLC circuitry in presence of a wall structure is developed, on the basis of MPIE and the Method of Moments.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 31 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

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Article

Antonios E. Tzinevrakis, Dimitrios K. Tsanakas and Evangelos I. Mimos

The paper aims to highlight the efficiency of double complex numbers for the complete analysis of the intensity of the electric field produced by power lines.

Abstract

Purpose

The paper aims to highlight the efficiency of double complex numbers for the complete analysis of the intensity of the electric field produced by power lines.

Design/methodology/approach

One set of complex numbers is used to represent all the plane vectors (vector distances) and another set of complex numbers is used to represent all the sinusoidal time varying quantities (electric charges and voltages). The simultaneous representation of vector distances and sinusoidal time varying quantities with complex numbers gives elegant expressions to the electric field vector and simplifies the mathematical relations to a great degree.

Findings

General analytical formulas are developed for the direct calculation of all the parameters of the elliptically rotating electric field (rms value, major and minor semi‐axis of the ellipse, angles of the semi‐axes, tracing direction, polarization). The analytical formulas depend on the components of the double complex number.

Research limitations/implications

The proposed method can be applied only on 2D problems, especially power lines where the electric field vector can be expressed as a double complex number.

Originality/value

Double complex numbers are proved in this paper as a very effective mathematical tool for the complete analysis of the electric field produced by power lines. The expression of the electric field vector as a double complex number allows the direct calculation of all the parameters of the electric field with analytical relations.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 32 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

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