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This paper aims to suggest a new revolutionary method and installation for flight on Earth and into outer space.
Abstract
Purpose
This paper aims to suggest a new revolutionary method and installation for flight on Earth and into outer space.
Design/methodology/approach
Methods of electromagnetic physics are used for research and the theory of levitation vehicles is developed and its possibilities researched.
Findings
It was found that levitation devices and electricity storage make a jump in aviation, space, storage and transfer energy and many branches of industry.
Practical implications
Many projects were calculated using different versions of the offered AB engine: a small device for levitation‐flight of a human (including flight from Earth to outer space), fly VTOL car (track), big VTOL aircraft, suspended low‐altitude stationary satellite, powerful Space Shuttle‐like booster for travel to the Moon and Mars without spending energy (spent energy is replenished in braking when the ship returns from another planet to its point of origin), using AB‐devices in military, in sea‐going ships (submarines), in energy industry (for example, as small storage of electric energy) and so on. The vehicles equipped with AB propulsion can take flight for days and cover distances of 10,000s of kilometers at hypersonic or extra‐atmosphere space speeds.
Originality/value
The paper promises a new revolutionary method of flight on Earth and into outer space.
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Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields…
Abstract
Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields. Looks at the coupling of fields in a device or a system as a prescribed effect. Points out that there are 12 contributions included ‐ covering magnetic levitation or induction heating, superconducting devices and possible effects to the human body due to electric impressed fields.
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This paper is designed to encourage electronic device designers to take a new look at a recent technology, Hall‐effect sensing, that has seen exceptional growth in certain areas…
Abstract
Purpose
This paper is designed to encourage electronic device designers to take a new look at a recent technology, Hall‐effect sensing, that has seen exceptional growth in certain areas, but could find much wider application and acceptance due to new supporting technologies.
Design/methodology/approach
The paper introduces Hall‐effect technology, and then explores how it has been applied, in particular, differentiating between the primary types of Hall sensors, and the highly differentiated range of sensing behaviors they can provide. In addition, it explores some of the enabling technologies, such as advances in signal processing, that have made this technology so much more robust than in its earliest days. This allows the application of the extreme high‐reliability benefit of contactless Hall sensing to a broader range of applications than ever before.
Findings
In addition to the advances that have made Hall‐effect sensing more practical, there are additional contributions to the designs of complete solutions. These advances include power and space reduction, as well as integration of diagnostic and protection functions that allow Hall sensor ICs to provide the advanced data‐driven features that are becoming more in demand in miniaturized portable consumer electronics, automobiles, and other growing industries.
Research limitations/implications
The research is intended as a general introduction to an emerging, yet complex technology. It is limited to standard configurations, and simplified explanations of magnetic effects.
Originality/value
This paper can be of great value to application designers who specialize in either the mechanical or electrical engineering disciplines, and who would like a cross‐disciplinary introduction to this technology, which requires a foundation in both areas simultaneously. In addition, the somewhat mysterious realm of electromagnetics is presented in a practical way, allowing the reader to gain enough confidence to begin experimenting with this innovative technology.
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E. Costamagna, P. Di Barba and R. Palka
The purpose of this paper is to describe a twofold methodology for evaluating the force between field excitation system and bulk in a magnetic‐levitation device based on…
Abstract
Purpose
The purpose of this paper is to describe a twofold methodology for evaluating the force between field excitation system and bulk in a magnetic‐levitation device based on high‐temperature‐superconductors (HTS). The paper focuses on two‐dimensional field models for HTS bulks. As far as field analysis is concerned, the finite‐element method in two or three dimensions is used. Alternatively, the conformal mapping approach provides a flexible and accurate calculation tool, useful for the optimization of superconducting bearings.
Design/methodology/approach
Powerful mapping algorithms, developed recently for Schwarz‐Christoffel‐like transformations, have proven successful in analyzing the fields, both in the activation and in the operation condition of superconductor devices.
Findings
Assuming small displacements of the superconductor sample with respect to the excitation magnets, the force‐displacement curve was obtained for operational field cooling via Schwarz‐Christoffel maps.
Originality/value
The specific theory used is the substitution theorem for magnetic fields, along with its capability to take complex geometries into account, making it possible to model devices for real‐life applications. Using only a scalar potential, the procedure proposed for computing fields proves, in the conformally‐mapped plane, the superposition method already introduced in FEM‐based models.
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The main aim of this paper is to explain how numerical magnetic field analysis can be adopted for the simulation of the effects generated when a rope fault occurs. In particular…
Abstract
Purpose
The main aim of this paper is to explain how numerical magnetic field analysis can be adopted for the simulation of the effects generated when a rope fault occurs. In particular, some important aspects are examined regarding the magnetic flaw generated by internal and external rope faults and the capability of 2D and 3D magnetic field solutions to detect the magnetic flaws.
Design/methodology/approach
After a first explanation of the non‐destructive approach from the point of view of the many different methods that can be used to perform a test, an introduction about magnetic systems is provided. Then a 3D magnetic simulation, based on finite integrate technique, of the system is performed and the results compared with those obtained by a simpler 2D magnetic finite element analysis. In the 3D simulation real local damage to the rope is considered and the leakage fluxes around it plotted. A parametric simulation was performed by considering variations of the main geometrical parameters that in a real test can affect the results, such as the airgap between the rope and the measuring point (the position of the field sensors) and the radial position of the sensor itself. Finally, experimental results on the real prototype on many different commercial ropes are provided. In this last section an original method to evaluate the signal to noise ratio of the device is presented.
Findings
At first, a really good correspondence between 2D and 3D numerical results was observed. Then it was shown that the difference among the sensing capabilities of field probes placed around the rope is reduced when the position of the damage is higher than 90° in respect of the sensor itself. Moreover, when the angular distance between a sensor and a surface damage is higher than 90°, the damage signal provided by the sensor does not practically change.
Research limitations/implications
Although the development method is always the same, the presented results are valid only for the configuration considered here. The experimental results of the signal to noise ratio are reported only for a reduced number of ropes.
Practical implications
The design procedure can be adopted to develop real devices and to identify the best position of the field sensing system. In particular, the paper shows the difference between radial and axial components of the leakage fluxes around the damage and their variation when the defect moves along the device.
Originality/value
The paper shows a methodology based on 2D and 3D numerical magnetic field analysis for the design of a non‐destructive device for metallic ropes with particular attention being given to the influence of field sensor and damage positions.
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Daniel Ioan, Mihai Rebican and Antal Gasparics
The paper describes an efficient method to extract the B‐H nonlinear characteristic from the experimental flux‐current Φ‐I data obtained using a non‐uniform magnetic field device…
Abstract
The paper describes an efficient method to extract the B‐H nonlinear characteristic from the experimental flux‐current Φ‐I data obtained using a non‐uniform magnetic field device. Both functions are monotonically piecewise linear approximated with the same number of breakpoints. The method was successfully applied to characterize the ribbon core material of a fluxset magnetic field sector. In this case the hysteresis loop and the lumped magnetic circuit were extracted. Comparison with experimental results validates the proposed method.
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P. Di Barba, F. Dughiero and E. Sieni
The purpose of the paper is to propose a cost‐effective method of non‐parametric optimisation in order to explore shapes of a magnetic pole, in the search for the optimal one…
Abstract
Purpose
The purpose of the paper is to propose a cost‐effective method of non‐parametric optimisation in order to explore shapes of a magnetic pole, in the search for the optimal one fulfilling a prescribed objective function.
Design/methodology/approach
The boundary of the magnetic field region to synthesize is considered as a moving boundary separating two materials (air and ferrite). An objective‐function dependent velocity field is defined, in order to update the position of nodes located along the unknown boundary. Specifically, a uniform magnetic field within the controlled region is aimed at.
Findings
The application of the proposed method to the design of a magnet for magnetic‐fluid hyperthermia made it possible to reduce the field deviation with a little computational effort.
Practical implications
Instead of using a standard algorithm of numerical minimisation to find the optimal search direction, a field‐dependent velocity proportional to the objective function value is exploited. This way, the motion of the boundary towards the optimal shape is automatically driven: in principle, in fact, the velocity reaches the zero value at the optimum.
Originality/value
Thanks to the kinematic law governing the movement of the boundary to synthesize, the overall computational cost is low. Moreover, the non‐parametric approach to the shape synthesis preserves the advantage of a broad search space.
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Zhenmin Wang, Wenyan Fan, Fangxiang Xie and Chunxian Ye
This paper aims to present an 8 kW LLC resonant converter designed for plasma power supply with higher efficiency and lighter structure. It presents how to solve the problems of…
Abstract
Purpose
This paper aims to present an 8 kW LLC resonant converter designed for plasma power supply with higher efficiency and lighter structure. It presents how to solve the problems of large volume and weight, low performance and low efficiency of traditional plasma power supply.
Design/methodology/approach
At present, conventional silicon (Si) power devices’ switching performance is close to the theoretical limit determined by its material properties; the next-generation silicon carbide (SiC) power devices with outstanding advantages can be used to optimal design. This 8 kW LLC resonant converter prototype with silicon carbide (SiC) power devices with a modulated switching frequency ranges from 100 to 400 kHz.
Findings
The experimental results show that the topology, switching loss, rectifier loss, transformer loss and drive circuit of the full-bridge LLC silicon carbide (SiC) plasma power supply can be optimized.
Research limitations/implications
Due to the selected research object (plasma power supply), this study may have limited universality. The authors encourage the study of high frequency resonant converters for other applications such as argon arc welding.
Practical implications
This study provides a practical application for users to improve the quality of plasma welding.
Originality/value
The experimental results show that the full-bridge LLC silicon carbide (SiC) plasma power supply is preferred in operation under conditions of high frequency and high voltage. And its efficiency can reach 98%, making it lighter, more compact and more efficient than previous designs.
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Hakan Koseni and Ali Bekir Yildiz
This paper aims to propose an efficient model for analysis of power electronic circuits with integrated magnetic components.
Abstract
Purpose
This paper aims to propose an efficient model for analysis of power electronic circuits with integrated magnetic components.
Design/methodology/approach
The inductance modeling technique is used as the traditional method for analyzing magnetic components. This model is simple and enough to generate for individual components, that is, an inductor and a transformer. However, it becomes difficult to realize this model for the integrated magnetic structures. This paper shows an appropriate model for individual magnetic components as well as integrated magnetic components and its application to magnetically coupled DC–DC converters. Gyrator–capacitor (G–C) modeling offers a unified, reasonable way of understanding the magnetic components commonly met with in power electronics and the other disciplines.
Findings
G–C model allows any electrical and magnetic circuit to be simultaneously simulated with circuit simulators. In this regard, this paper gives a complete simulation model and analysis as an illustrative example. There is no limitation of this paper or future works. The proposed G–C model can be applied to all power electronic circuits having integrated magnetic components.
Originality/value
In the proposed model, the magnetic circuit is converted to a pure electric circuit with capacitors and controlled sources; every winding is replaced with a pair of current controlled voltage sources, namely, a gyrator.
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Ding-jian Huang, Li-gang Yao, Wen-jian Li and Jun Zhang
The purpose of this research is to achieve a novel magnetic nutation drive for an industry robotic wrist reducer.
Abstract
Purpose
The purpose of this research is to achieve a novel magnetic nutation drive for an industry robotic wrist reducer.
Design/methodology/approach
A novel magnetic nutation drive is proposed, and the structure and principle of the designed magnetic nutation drive are described in this study. Three-dimensional finite element analysis is used to compute the magnetic and torque of the magnetic nutation drive. Furthermore, a prototype of this novel magnetic nutation drive device is developed with 3D printing technology and tested to verify the feasibility of the proposed structure and principle.
Findings
The simulation and experimental results indicated that the proposed magnetic nutation drive device could meet the desired specifications, and that this novel magnetic nutation drive device successfully realized the non-contact transmission ratio of 105:1 required for a robotic wrist reducer.
Practical implications
This novel magnetic nutation drive is low-cost and easy to make and use, and which provides the non-contact transmission ratio of 105:1 required for a robotic wrist reducer.
Originality/value
For the first time, this research applies the permanent magnet drive technology to nutation drive and puts forward a new non-contact nutation drive mode. The novel drive mode can solve some problems of the traditional mechanical contact nutation drive, such as vibration, friction loss, mechanical fatigue and necessity of lubrication. The proposed non-contact nutation drive device can achieve a high reduction ratio with compact structure and can be suitable for industry application.
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