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Seeks to determine the optimal shape design of an induction heating device.

Presents, through a case study, the optimal shape design of a multiple coil inductor for surface heating. Resorts to a procedure of automated optimal design, based on evolutionary optimisation and processing both continuous‐valued and discrete‐valued variables.

Demonstrates that it is possible to solve the design problem routinely using an optimisation tool (OptiNet) that is built to work seamlessly with a coupled electromagnetic‐thermal simulation.

Every design criterion that is likely to be of interest to a designer of industrial applications can be described to the system and optimised in a reasonable time frame.

This paper aims to propose and establish a set of new benchmark models to investigate and confidently validate the modeling and prediction of total stray-field loss inside magnetic and non-magnetic components under harmonics-direct current (HDC) hybrid excitations. As a new member-set (P21^e) of the testing electromagnetic analysis methods Problem 21 Family, the focus is on efficient analysis methods and accurate material property modeling under complex excitations.

This P21^e-based benchmarking covers the design of new benchmark models with magnetic flux compensation, the establishment of a new benchmark measurement system with HDC hybrid excitation, the formulation of the testing program (such as defined Cases I–V) and the measurement and prediction of material properties under HDC hybrid excitations, to test electromagnetic analysis methods and finite element (FE) computation models and investigate the electromagnetic behavior of typical magnetic and electromagnetic shields in electrical equipment.

The updated Problem 21 Family (V.2021) can now be used to investigate and validate the total power loss and the different shielding performance of magnetic and electromagnetic shields under various HDC hybrid excitations, including the different spatial distributions of the same excitation parameters. The new member-set (P21^e) with magnetic flux compensation can experimentally determine the total power loss inside the load-component, which helps to validate the numerical modeling and simulation with confidence. The additional iron loss inside the laminated sheets caused by the magnetic flux normal to the laminations must be correctly modeled and predicted during the design and analysis. It is also observed that the magnetic properties (B27R090) measured in the rolling and transverse directions with different direct current (DC) biasing magnetic field are quite different from each other.

The future benchmarking target is to study the effects of stronger HDC hybrid excitations on the internal loss behavior and the microstructure of magnetic load components.

This paper proposes a new extension of Problem 21 Family (1993–2021) with the upgraded excitation, involving multi-harmonics and DC bias. The alternating current (AC) and DC excitation can be applied at the two sides of the model’s load-component to avoid the adverse impact on the AC and DC power supply and investigate the effect of different AC and DC hybrid patterns on the total loss inside the load-component. The overall effectiveness of numerical modeling and simulation is highlighted and achieved via combining the efficient electromagnetic analysis methods and solvers, the reliable material property modeling and prediction under complex excitations and the precise FE computation model using partition processing. The outcome of this project will be beneficial to large-scale and high-performance numerical modeling.

Several second order edge elements have been applied to solving magnetostatic problems. The performances of these elements are compared through an example of magnetic circuit. In order to ensure the compatibility of the system equations and hence the convergence, the current density is represented by the curl of a source field. This avoids an explicit gauge condition which is cumbersome in the case of high order elements.

The purpose of the paper is to give a review of TEAM Problem 21, focus on its extended progress in engineering-oriented developments, and report the new benchmarking activity undertaken by the authors.

Testing electromagnetic analysis methods; verify computation models; detail the field behavior of typical magnetic structure; benefit to large-scale numerical modeling.

The calculated results of power loss and magnetic flux for all the member models agree well with the measured ones. The updated Problem 21 Family can now be used to model the saturation effect in the magnetic plate or the lamination by increasing the exciting currents. The new member model P21d-M allows further detailed examination of the electromagnetic behavior inside laminated sheets. The variation of both the iron loss and the magnetic flux with the excitation patterns and magnetic property data can be investigated inside the laminated sheets and the magnetic plate.

In order to model the possible saturation level of magnetic steel using Ar-V-Ar or T-Ω solvers, the exciting currents are increased from 10 to 50 A. In order to model the iron loss and magnetic flux densities inside the laminated sheets, a very simplified model, P21d-M of Problem 21 Family as shown in Figure 2, has been proposed.

This study, a theoretical article, aims to introduce new institutionalism as a framework through which business and management researchers can explore the significance of artificial intelligence (AI) in organizations. Although the new institutional theory is a fully established research program, the neo-institutional literature on AI is almost non-existent. There is, therefore, a need to develop a deeper understanding of AI as both the product of institutional forces and as an institutional force in its own right.

The authors follow the top-down approach. Accordingly, the authors first briefly describe the new institutionalism, trace its historical development and introduce its fundamental concepts: institutional legitimacy, environment and isomorphism. Then, the authors use those as the basis for the queries to perform a scoping review on the institutional role of AI in organizations.

The findings reveal that a comprehensive theory on AI is largely absent from business and management literature. The new institutionalism is only one of many possible theoretical perspectives (both contextually novel and insightful) from which researchers can study AI in organizational settings.

The authors use the insights from new institutionalism to illustrate how a particular social theory can fit into the larger theoretical framework for AI in organizations. The authors also formulate four broad research questions to guide researchers interested in studying the institutional significance of AI. Finally, the authors include a section providing concrete examples of how to study AI-related institutional dynamics in business and management.

The paper presents a new variant of the H-Φ field formulation for solving 3-D magnetostatic and frequency domain eddy current problems. The suggested formulation uses the vector and scalar tetrahedral elements within conducting and non-conducting domains, respectively. The presented numerical method is capable of solving multiply connected regions and eliminates the need for computing the source current density and the source magnetic field before the actual magnetostatic and eddy current simulations. The obtained magnetostatic results are verified by comparison against the corresponding results of the standard stationary current distribution analysis combined with the Biot-Savart integration. The accuracy of the eddy current results is demonstrated by comparison against the classical A-A-f approach in frequency domain.

The theory and implementation of the new H-Φ magnetostatic and eddy current solver is presented in detail. The method delivers reliable results without the need to compute the source current density and source magnetic field before the actual simulation.

The proposed H-Φ produce radically smaller and considerably better conditioned equation systems than the alternative A-A approach, which usually requires the unphysical regularization in terms of a low electric conductivity value within the nonconductive domain.

The presented numerical method is capable of solving multiply connected regions and eliminates the need for computing the source current density and the source magnetic field before the actual magnetostatic and eddy current simulations.

Connection boundary conditions are studied with the finite element method using different types of mixed finite elements, i.e. nodal, edge and facet elements of different shapes and degrees, used in both b‐ and h‐conform formulations. The developed associated tools are first applied to periodicity boundary conditions before being applied to the treatment of the moving band in 2D and 3D. This step by step approach enables their validation before pointing out the effect of the considered elements on the accuracy of the moving band method. A special attention is given to the consistency of these boundary conditions with gauge conditions and source magnetic fields.

Presents a review on implementing finite element methods on supercomputers, workstations and PCs and gives main trends in hardware and software developments. An appendix included at the end of the paper presents a bibliography on the subjects retrospectively to 1985 and approximately 1,100 references are listed.

Two‐ and three‐dimensional computations of the cogging torque in a brushless dc motor are compared with measurements for both skewed and unskewed stators. The modeling of stator skew is considered both using a full three dimensional model with and without material anisotropy and using a set of displaced two‐dimensional slices. The errors inherent in the latter approach are discussed. A cost/benefit trade‐off between three‐dimensional and two‐dimensional analyses is considered.

This paper presents a method of coupling magnetostatic potential formulations with electrical circuits for the 3D FEM. Allowing for the current density distribution in stranded conductors, two vectors N and K are introduced. A systematic method of decomposing both vectors in Whitney’s element spaces is suggested. This method can be used for coils with a complex shape. As an example of application a three‐phase transformer is studied.