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The purpose of this paper is to investigate how the new theory on the general systemic yoyos can be plausibly employed to provide novel explanations for some of the well‐known laboratory experiments of physics and how a different theory that is more refined than the currently accepted theories can be established for illustrating phenomena that have not been completely explainable by using the traditional theories.

The general field structures of systemic yoyos, combined with some of the well‐known laboratory observation of physics, are employed as the basic methodology for the current paper.

Owing to the co‐existence of magnetic fields and ring‐shaped negative electric fields, all possible ways for an electromagneton to be fired into a stable, uniform‐intensity magnetic field are investigated. How such an electromagneton could be traveling under the mutual influence of the fields is described with details.

The value of this paper lies on the fact that it points out a brand new and practically applicable theory for looking at some of the well‐recorded phenomena of electromagnetism.

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.

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.

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.

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.

The purpose of this paper is to investigate yoyo potential difference and induction of electric yoyo flows by using the general systemic yoyo model and available quantitative tools.

Empirical laws and well‐known laboratory experiments of physics are revisited in light of the spinning yoyo method and thinking logic. When appropriate, relevant quantitative methods are established.

By generalizing the concept of electromotive force, the paper introduces that of meridian motive forces (MMF). By considering two possible cases when electric yoyo flows can be induced within a return circuit, the paper uses specific examples to compute yoyo potential differences, the forces needed to pull a conductive wire in a magnetic yoyo field, and the total flux of magnetic yoyo field passing through a return circuit. When the paper tries to address the questions of how an electric yoyo current in a circuit is produced and what force could get around the resistance of metals to make electric yoyo charges move around inside return circuits, the paper successfully establishes a theoretical explanation for why Lenz's law about the direction of induced electric currents holds true. At the end, the paper develops a quantitative formula for practically calculating desired MMF.

This paper provides the first ever theoretical explanation for why Lenz's law could be true. It is expected that this explanation would be equally applicable in the study of social systems.

The purpose of this study is to model the electric field distribution in 3D in the vicinity of 400 kV power line to determine the field impact on the environment and on the human body depending on the person location and presence of other objects.

The real 3D geometry of the three-phase line because of the line sag presence and existence of additional objects in its vicinity is considered. The time-harmonic electric field has been modeled, taking into account 1,200 phase shifting between the three-phase, 50 Hz currents. The study has been carried out using the finite element method (FEM) and COMSOL Multiphysics 5.2 software package. Special attention was paid to the field at a height of 2 m from the ground, to estimate the field influence on the located human body in the studied area (in relation to the limits for permissible electric field values).

3D map of electric field in the line vicinity and the electric field strength distribution along the observation surface (2 m from the ground) are determined for several region configurations: without additional objects, human presence just under the line, human at a certain distance from the line and presence of human and a tree. The simulation model was validated on the basis of comparison with computed and experimental data presented in the literature.

3D FEM modeling makes it possible to consider the real environment configuration, presence of line sag and additional objects with different material properties and obtaining of field quantities at any point of observation.

In high voltage direct current cable systems, cable joints are known as the least reliable components due to the use of multiple dielectrics. Resulting from the electric field and temperature depending conductivity of the different dielectrics, field enhancement at critical areas, e.g. triple points, may result in accelerated aging and the failure of the component. To reduce the stress, different field grading techniques are applied. The purpose of this study is to investigate different grading techniques for cable joints. Different shapes of the electrode and a varying nonlinear conductivity of field grading materials (FGM) are used for the simulation of the electric field.

Coupled electro-thermal field simulations are applied for different joint geometries, to obtain the stationary electric field. Electric field simulations in cable joint using geometric and nonlinear field grading techniques are shown.

Using the geometric field grading, the shape of the stress cone determines the field values in critical areas (triple points). High stress reduction is obtained for a certain curvature of the stress cone. For the nonlinear stress control, materials with a higher conductivity in comparison to the cable and the joint material are used. A field reduction is obtained by increasing the total conductivity. On the other hand, this is also increasing the insulation losses within the total FGM. More applicable is the decrease of the switching field or the increase of nonlinearity, which is only locally increase the conductivity and the insulation losses. Furthermore, simulations results show that an approximately constant field reduction is obtained, if the nonlinearity is above a certain threshold.

This study is restricted to a field dependency of FGM only. For impulse voltages, high temperature and electric conductivity values my result in a thermal runaway. Furthermore, only direct current field grading techniques are studied.

The field grading of cable joints, using geometric and nonlinear techniques, is analyzed. A comparison between the electric field, by varying the curvature of the ground stress cone or the FGM conductivity constants in a complex joint geometry is novel. With its effect on the electric fields, general requirements for the geometry (geometric field grading) or the values of the FGM constants (nonlinear field grading) are defined to obtain a sufficient field grading.

To determine the electrical field E₁(t) in spherical and cylindrical gas voids existing in an insulator by considering surface conductivity of gas voids having an electrical permittivity of ε₁ and conductivity of γ₁ for DC and AC situations.

Analytical expressions satisfying Laplace equation for inside and outside of the cylindrical and spherical gas voids in an insulator located in an external electrical field having a definite time dependent character, have been derived by considering the surface conductivity of the gas void. The coefficients included by these analytical expressions have been determined by utilizing the continuity equation of the current on the surface of the voids.

It has been demonstrated that the electrical field remains uniform in spherical and cylindrical gas voids when the surface conductivity of gas void has been considered. It has been determined that the contact charging process of different shaped particles has an exponential characteristic, and some expressions have been derived to determine the time constants of this process for practical purposes.

The results have been applied to the problems about contact charging of semi‐spherical and semi‐cylindrical insulated particles located at a charged surface and problems about the calculation of onset discharging voltage of ionization process in dielectric including gas voids.

For spherical and cylindrical gas voids, the onset discharging voltage corresponding to the ionization process occurring in gas voids has increased by increasing the surface conductivity of the void. For the limit value of the surface conductivity, the voids in the insulator behaves like metal particles distributed into the insulator, for this reason, at the outside of the void, especially in the regions where the voids are close to the electrodes and each other, the electrical field will be non‐uniform and will increase. This situation will cause the ignition of the partial discharge and destroy to the insulator.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

The purpose of this paper is to use the general systemic yoyo model to illustrate why electric fields and magnetic fields can manifest each other and interact with each other.

The coordinated interaction of eddy and meridian fields of spinning yoyos is employed as our methodology for the investigation in this paper. At the end, the First Law on State of Motion is beautifully utilized.

Among many new theoretical discoveries, systemic yoyo models are provided to understand electric currents and the induced magnetic fields, which lead to a distinction between the yoyo structures of permanent magnets and those of the magnetic field induced by electric currents. It is theoretically shown why all fields in nature, such as electric, magnetic, universal, gravitational, and nuclear fields, have to exist in pairs of opposite polarities, even though one polarity might not be visible or recognizable with the current technology. Using the quark structures of spinning yoyos, an explanation is provided for why protons carry positive electric fields, while neutrons are electrically neutral.

One of the originalities of this paper is about its unified theory underlying many observed phenomena of electric and magnetic fields.

This paper sets out to detect and characterize electric fields in the ground (such as stray current fields) using a tandem time/frequency method of signal analysis.

Results were obtained from investigations performed in the presence of a generated electric field with controlled variable characteristics, and in the presence of an electric field generated by a tramline. The analysis of measurement registers was performed using Short‐Time Fourier Transformation. The results were presented in the form of spectrograms, which illustrate changes in the spectral power density of the measured signal versus time.

Tandem time/frequency analysis reveals the random or deterministic character of the electric field, enabling its complete time/frequency characteristics to be obtained. Such information is inaccessible using exclusively the frequency analysis methods that utilize classical Fourier transformations. Moreover, an analysis of the spectral power density distribution of the signals in three directions on the ground surface makes it possible to define the localization of the field source.

Analysis methods for electric fields in the ground should be adapted to the evaluation of non‐stationary signals because the stray currents are of this type. Such a possibility is given by combined analysis in the domains of time and frequency. This method can be used as complementary to applied measurement techniques of stray current interference.

The method of electric field detection and characterization, as related to stray currents, previously has not been presented in the literature. This method of signal analysis may be adopted for other investigations that are reliant on the registration of voltages or potentials characterized by arbitrary frequencies.

This paper aims to focus on the finite element method in the frequency domain (FD-FEM) for the transient electric field in the non-sinusoidal steady state under the non-sinusoidal periodic voltage excitation.

Firstly, the boundary value problem of the transient electric field in the frequency domain is described, and the finite element equation of the FD-FEM is derived by Galerkin’s method. Secondly, the constrained electric field equation on the boundary in the frequency domain (FD-CEFEB) is also derived, which can solve the electric field intensity on the boundary and the dielectric interface with high accuracy. Thirdly, the calculation procedures of the FD-FEM with FD-CEFEB are introduced in detail. Finally, a numerical example of the press-packed insulated gate bipolar transistor under the working condition of the repetitive turn-on and turn-off is given.

The FD-CEFEB improves numerical accuracy of electric field intensity on the boundary and interfacial charge density, which can be achieved by modifying the existing FD-FEMs’ code in appropriate steps. Moreover, the proposed FD-FEM and the FD-CEFEB will only increase calculation costs by a little compared with the traditional FD-FEMs.

The FD-CEFEB can directly solve the electric field intensity on the boundary and the dielectric interface with high accuracy. This paper provides a new FD-FEM for the transient electric field in the non-sinusoidal steady state with high accuracy, which is suitable for combined insulation structure with a long time constant.