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The technique for the simulation of the dynamic behaviour of rotating machines presented in the paper is based on an equivalent circuit representation of the magnetic configuration. The circuit parameters are obtained by a preliminary automated sequence of magnetostatic FEM analyses and take into account the local magnetic saturations. The adopted solution technique is based on an invariant network topology approach: its application, presented for the operation analysis of a low‐power synchronous generator, allows a great reduction of the calculation time in comparison with a commercial FEM code for the transient simulation.

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.

The purpose of this study is to reduce the cogging torque in axial flux permanent magnet (AFPM) machine using optimal magnet shape.

This study analyzes different magnet shapes for AFPM machine performance enhancement. Three-dimensional (3D) finite element analysis is performed to see the effects of pole shaping on the cogging torque of the AFPM machine.

The magnetic pole shape has a significant effect on cogging torque and overall efficiency. The conventional model has the highest torque whereas the conventional skewing affected cogging torque positively and significantly reduced the cogging torque. The combination of skewing the pole along with face curving is more effective and decreases the cogging torque from 3.88 Nm to 1.5 Nm.

Rare-earth magnets are the most expensive and important part of AFPM machines. Shape and volume optimization of rare-earth magnets is crucial for the performance of AFPM machines. The research aims to analyze the different permanent magnet designs for performance improvement of the AFPM machine. Conventional flat top trapezoidal, curved-top and skewed-magnet shapes are analyzed and the performance of the AFPM machine is compared with different magnet shapes. Curved-top shape and skewed magnet significantly reduce the cogging torque. Furthermore, a combination of curved-top shape and skew magnet shape is proposed to reduce the cogging torque further and improve the AFPM machine’s overall performance. Newly proposed magnet profile gives skewed curve magnet shapes which reduce the cogging torque further. 3D finite element analysis has been used to analyze the single-sided AFPM with all four different magnet shapes. The research focuses on single-sided AFPM machines, but the results are also valid for double-sided AFPM machines and can be extended to other topologies of AFPM machines.

Electromagnetic actuators, with very specific features for industrial processes, are needed much more for an increase in reliability and dynamic. To reach the wanted features, the actuator has to be designed and its performance has to be quantified with good accuracy and reasonable computation time. The purpose of this paper is to present the design and the study of a permanent magnet linear actuator.

The first design of the permanent magnet linear actuator has been introduced from electromechanical considerations. Then, both models utilized to study the actuator are presented: the permeance network model (PNM) and the 3D finite element model. These models are used to quantify the performance of the prototype. Owing to its speed, the influence of geometric parameters on the performances are studied by the PNM. Then, both models are used to perform calculations on global variables. A prototype of the designed actuator has been built up and the results obtained by both models are compared with the measurements.

The developed model has been used to study the behaviour of the designed actuator. Using the 3D‐FEM, the local phenomena have been highlighted as the magnetic flux density and the induced current. Then, global variables as the no load fluxes and the forces at load have been determined. The results obtained by both models have been compared together and show a good agreement. They are also very close to the measurements achieved on the prototype constructed.

This paper shows that it is possible to use a PNM model to design a permanent magnet linear actuator with a relative good accuracy. The PNM developed does not permit one to calculate the cogging forces and does not take into account the induced currents but it gives accurate results when the interest is focused only on the magnetostatic load operating. The comparison with the results given by 3D‐FEM and to the measurements shows a good agreement.

The purpose of this paper is to analyze the characteristics of the factors influencing the effect of magnetic levitation, including the impedance angle of the levitated coil, number of turns, material parameter, frequency of excitation and geometric parameters. The final purpose is to provide approaches to increasing the levitation effect.

Some design principles and strategies for levitation systems are suggested, such as selecting the number of turns of the levitated coil, choosing the frequency of excitation considering the saturation phenomenon of levitation force against frequency and deciding the section area of the excitation coil and its ratio of height and thickness.

The magnetic force is not always repulsive in a cycle. Therefore, the key approach to increasing the levitation is to increase the period when the force is repulsive and decrease the time when attractive. The impedance angle of the equivalent circuit of the levitated coil determines the ratio of the two periods, and the larger the angle, the longer the repulsion period. A valuable finding is that a saturation situation exists between the levitation force and frequency; that is, when the frequency increases to a certain value, the increasing degree of force tends to decrease as the frequency increases.

Some influential characteristics were found in some factors against the effect of the levitation system, which is beneficial for improving the efficiency of systems. For example, owing to the saturation phenomenon of the frequency, it is useless to continue increasing the frequency and the copper-levitated coil does not bring much greater force effectiveness than the aluminum coil.

This paper aims to provide the mathematical background for representation of permanent magnet AC machines in terms of rotating magnetic field waves of any shape instead of being restricted to the sinusoidal. The general idea is to replace the inductances in the mathematical model of the machine by means of adequate time functions of the flux linkage.

On the basis of several 2D or 3D solutions obtained by the finite element (FE) approach, the set of basis functions is generated for further post‐processing. These functions enable fast and accurate computations of back EMF time shape at any load conditions, which in turn gives the instantaneous values of terminal quantities like torque or voltage, depending on the regime of interest.

The permanent magnet machine (PMM) has been represented by means of the traveling non‐dispersive waves of the flux density in the air gap rotating with specified group velocity. The conversion between distributions of the flux density in space and flux linkage in time is obtained through filtering in the spectral domain using 2D or 3D discrete Fourier transform. The change of magnetic saturation due to arbitrary value of the machine load is incorporated by the interpolation between known magnitudes of the basis functions at given a priori RMS values of phase currents. It has been proved that a sinusoidal field machine is particular to the presented theory.

The paper deals with the steady state of PMM; however, the extension towards the transient analysis is possible.

The paper presents a fast and accurate model of PMM for the analysis of its basic electromagnetic quantities.

The analysis of terminal quantities being different in time from sinusoidal or constant distributions, both electrical and mechanical, is usually performed by means of a time stepping approach. The required computing effort is still too high for real time applications. The presented method starts from single FE solutions and converts their accuracy on the set of mutually orthogonal functions having the clear representation in the spectral, mode‐frequency domain. The magnitudes of these basic functions enable one to express the electromagnetic power in a form equivalent to classic dq representation, but not constrained by sinusoidal input quantities.

The purpose of this paper is to develop a novel coupled analysis method for synchronous rectification alternators.

An ideal diode module is embedded in a rectification circuit. The resistance of the diode module is set such that it is equal to the on-resistance of the MOS-FET modules in the generation mode. In a mode without power generation, the motor voltage is less than the bus voltage; a sufficiently large value is defined for simulating the infinite resistance.

Because there is no need to decide the switch timing in advance, only one round of coupled analysis is needed to evaluate the synchronous rectification alternators.

As limited case study is denoted in this paper, much more case studies are needed to be discussed.

By using the proposed method, it can be fulfilled that generation characteristic of automotive alternators can be evaluated without using the control simulation or pre-conducted analysis to decide the switch timing.

By using the proposed method, it can be fulfilled that generation characteristic of automotive alternators can be evaluated without using the control simulation or pre-conducted analysis to decide the switch timing.

In the proposed methods, the definition of diode module differs from that of a conventional coupled analysis.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

This study aims to analyze the relationship between the nonpathological traits of narcissism and decisions under conditions of uncertainty and risk in light of the prospect (PT) and fuzzy-trace theories (FTT).

This paper conducted an empirical-theoretical study with 210 Brazilian academics from the business area (accountants and managers), using a self-reported questionnaire to collect data. This paper analyzed the data through descriptive statistical techniques, correlation, test of hypotheses and logistic regression.

The results point to a lower disposition of respondents to narcissistic traits, although the characteristics of self-sufficiency, authority, exploitation and superiority have been demonstrated. Most participants chose the sure gain in positive scenarios and risk in light of possibility of losses. However, those with high levels of narcissism showed higher propensity to make risky decisions, both in positive and negative scenarios.

The empirical results about risky decision-making behavior of individuals with narcissist traits spur further investigation on the impacts of attitudes and behaviors in organizations as they are affected by psychosocial factors. These attitudes and behaviors, reflected in administrative and financial reports, influence future decisions of investors.

The interaction between the areas of business administration and psychology in regard to the effects of the narcissist personality trait and the FTT is both original and valuable for the business area. The simplest scenario based on the FTT theory can help eliminate issues around the interpretation and complexities of calculations regarding decision-making scenarios in PT format.