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This paper aims to investigate the impact of combining grain-oriented electrical steel (GOES) grades on specific iron losses and the flux density distribution within a single-phase magnetic core.

This paper presents the results of finite-element method (FEM) simulations investigating the impact of mixing two different GOES grades on losses of a single-phase magnetic core. The authors used different models: a 3D model with a highly detailed geometry including both saturation and anisotropy, as well as a simplified 2D model to save computation time. The behavior of the flux distribution in the mixed magnetic core is analyzed. Finally, the results from the numerical simulations are compared with experimental results.

The specific iron losses of a mixed magnetic core exhibit a nonlinear decrease with respect to the GOES grade with the lowest losses. Analyzing the magnetic core behavior using 2D and 3D FEM shows that the rolling direction of the GOES grades plays a critical role on the nonlinearity variation of the specific losses.

The novelty of this research lies in achieving an optimum trade-off between the manufacturing cost and the core efficiency by combining conventional and high-performance GOES grade in a single-phase magnetic core.

The purpose of this paper is to exploit the optimal performances of each magnetic material in terms of low iron losses and high saturation flux density to improve the efficiency and the power density of the selected motor.

This paper presents a study to improve the power density and efficiency of e-motors for electric traction applications with high operating speed. The studied machine is a yokeless-stator axial flux permanent magnet synchronous motor with a dual rotor. The methodology consists in using different magnetic materials for an optimal design of the stator and rotor magnetic circuits to improve the motor performance. The candidate magnetic materials, adapted to the constraints of e-mobility, are made of thin laminations of Si-Fe nonoriented grain electrical steel, Si-Fe grain-oriented electrical steel (GOES) and iron-cobalt Permendur electrical steel (Co-Fe).

The mixed GOES-Co-Fe structure allows to reach 10 kW/kg in rated power density and a high efficiency in city driving conditions. This structure allows to make the powertrain less energy consuming in the battery electric vehicles and to reduce CO₂ emissions in hybrid electric vehicles.

The originality of this study lies in the improvement of both power density and efficiency of the electric motor in automotive application by using different magnetic materials through a multiobjective optimization.

Technological innovation has made it possible to review how a film cues particular reactions on the part of the viewers. The purpose of this paper is to capture and interpret visual perception and attention by the simultaneous use of eye tracking and electroencephalography (EEG) technologies.

The authors have developed a method for joint analysis of EEG and eye tracking. To achieve this goal, an algorithm was implemented to capture and interpret visual perception and attention by the simultaneous use of eye tracking and EEG technologies. All parameters have been measured as a function of the relationship between the tested signals, which, in turn, allowed for a more accurate validation of hypotheses by appropriately selected calculations.

The results of this study revealed a coherence between EEG and eye tracking that are of particular relevance for human perception.

This paper endeavors both to capture and interpret visual perception and attention by the simultaneous use of eye tracking and EEG technologies. Eye tracking provides a powerful real-time measure of viewer region of interest. EEG technologies provides data regarding the viewer’s emotional states while watching the movie.

The approach in this paper is distinct from similar studies because it takes into account the integration of the eye tracking and EEG technologies. This paper provides a method for determining a fully functional video introspection system.

This paper aims to deal with a performance comparison of an 8/6 radial-flux switched reluctance machine (RFSRM) and an axial-flux switched reluctance machine (AFSRM), presenting equivalent active surfaces.

An axial machine was designed based on the equivalent active surfaces of a radial one. After estimating the machine inductances with a reluctance network, finite elements numerical models have been implemented for a more precise inductance determination and to estimate the electromagnetic torque for both machines. Finally, the AFSRM was thoroughly examined by analyzing the impact of some geometric parameters on its performance.

The comparison of the RFSRM and AFSRM at equivalent active surfaces showed that the obtained axial machine is more compact along with an improvement in the electromagnetic torque.

The equivalent AFSRM is more compact, therefore more interesting for transport and on-board applications.

The RFSRM and AFSRM performance comparison using the same active surfaces has not been done. Moreover, the AFSRM presented has a rare design with no rotor yoke and where the rotor teeth are encapsulated in a nonmagnetic structure, allowing a more compact design.

This paper aims to study the influence of supply voltage variations on the external magnetic field emitted by grid-powered induction machines (IMs).

Two models are developed in the paper to analyse, for different supply voltage values, the influence of the variations of the magnetizing voltage for which there is a link with the tangential component of the external flux. The first is an analytical model based on the IM single-phase-equivalent circuit with variable magnetizing reactance to take into account the saturation of the magnetic circuit. The second is a numerical finite element simulation to model the same phenomenon. Results of both models are analysed with experimental measures of the external flux.

The study shows that the amplitude of the external field strongly depends on supply voltage values.

The investigation is mainly focused on the tangential component of the external magnetic field which is of high importance concerning the applicability of non-invasive methods of diagnosis, as electromagnetic torque estimation developed by the authors or internal fault determination.

The originality of the paper concerns the characterization of the external flux with the supply voltage for IMs. It is shown that the magnetic circuit radiates external flux differently with the load and with the supply voltage.

The purpose of this paper is to present a comparative analysis concerning the influence of eddy currents on the distribution of the magnetic flux density in the laminated anisotropic structures.

The influence of the magnetic flux normal to the lamination surface is particularly analysed. Several models containing internal air gaps and overlapping are tested. For every structure, the eddy currents are first taken into account and then, they are neglected. At last, the 3D simulation of the anisotropic conductivity permits to analyse separately the longitudinal and normal flux in the structure and the eddy currents induced by those fluxes.

The study leads to a more realistic numerical model with conducting laminations. The results show that the normal flux does not turn at once on lamination. The normal and longitudinal fluxes induce eddy currents which modify the flux distribution in the laminated structure.

The results of the presented simulations make it possible to elaborate a more realistic numerical model of homogenized characteristics taking into account eddy currents.

The eddy currents induced by the fluxes modifies the field distribution in the structure and should be taken into account. The internal air‐gaps higher than 0.1 mm have an influence on the field distribution; the isolation between the laminations of 0.01 mm has a smaller but not negligible effect on the magnetic flux. The direction of the normal flux from one sheet to another one does not change immediately after the entrance of the lamination, the transition is progressive.