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Vibrations and acoustic noise are some of the fundamental problems in the design and exploitation of switched reluctance motors (SRMs). Adequate experimental and analysis methods may help to resolve these problems. This paper presents a theoretical analysis of the magnetic force distribution in SRM and a procedure for calculating the magnetic forces and the resulting vibrations based on the 2D finite element method. Magnetic field and force computations and a structural analysis of the stator have been carried out in order to compute the frequency spectrum of the generalized forces and displacements of the most relevant vibration modes. It is shown that for these vibration modes, the frequency spectrum can be predicted analytically. The theoretical and the numerical analyses have been applied to a 6/4 SRM and an experimental validation is presented.

The aim is to develop a nonlinear transformer model to achieve an accurate model to obtain the frequency components of the magnetizing current based on the harmonic voltages at the primary and secondary side. So, it can easily be implemented in a harmonic load‐flow program.

The transformer model is based on the harmonic balance method. The electric and magnetic equations of the transformer are derived from the electric and magnetic equivalent circuits.

The transformer model can be easily implemented in a harmonic load‐flow program. The accuracy of the model has been shown by comparing it with a finite element simulation. The transformer model can be used with asymmetrical supply voltages, because different saturation levels of the phases can occur. There is a coupling between the phases which can be concluded out of the asymmetrical currents in the transformer under symmetrical supply voltages.

The transformer model does not consider the iron losses and the interharmonics. In future work the transformer model will be used to study the harmonic losses in distribution networks, so the transformer losses due to these harmonics have to be considered. This can be achieved with a postcalculation process where the magnetic flux density is used to calculate the eddy current losses and the magnetic field intensity will be applied in a static Preisach model to quantify the hysteresis losses.

The model can be used in a harmonic load‐flow program in order to obtain more accurate simulations for the power system analysis and design.

The model presented in this paper is more detailed than similar papers found in literature (saturation of the yokes, coupling between the phases, interaction between different harmonics) and still it takes a brief simulation time.

To provide a discrete‐time nonlinear model for surface permanent‐magnet synchronous machines (SPMSMs) in order to discuss the stability of such machines.

Through differencing the co‐energy, obtained from a finite element method, the main flux path can be described by a complex reluctance. Furthermore, for a SPMSM, an equivalent circuit is presented that includes the eddy‐current losses and the voltage drops across stator resistance and leakage inductance. The model is transformed to a discrete‐time state‐space model by using a forward rectangular rule. By using a root locus technique, the stability of the new model is discussed.

From the calculated root locus it is concluded that the stability of a SPMSM is only guaranteed for certain values of the open loop gain. Moreover, by using the forward rectangular rule, it is concluded that a well‐considered time step has to be chosen.

The model considers the fundamental space harmonic components only. Moreover, the saturation of the leakage flux path is neglected.

As the model is formulated in discrete time, it can be used in modern drives where a digital controller is used.

This paper presents an equivalent electrical circuit for SPMSMs that takes into account the saturation of the magnetizing flux paths as well as the magnetic interaction between the two orthogonal magnetic axes.

In this paper a continuum description of deformable magnetized material including long‐range magnetic forces and magnetostriction is presented. Herein, magnetostriction and long‐range forces on the one hand, and magnetization and deformation on the other hand are considered simultaneously. Therefore, neither a strict distinction between the deformation due to magnetic forces and due to magnetostriction, nor a separation of the total free energy into magnetic and elastic energy is involved.

The purpose of this paper is to explore communication challenges related to geographic distance, with emphasis on differences in national culture and language between R&D and manufacturing engineers, in a development project faced with uncertainty and equivocality.

The results originate from a longitudinal single-case study of a commercial product development project.

Three communication challenges are identified: clarity of shared information, intention to share information, and responsiveness to information received. The challenges are strongly associated with differences in national culture and language. The study also indicates that the communication challenges cannot only be handled by the use of rich communication media, but also by employment of communication media of low richness such as e-mails or “picture books”.

The single-case study approach limits the ability to generalize the findings. Future research should thus focus on additional studies of geographically separated R&D and manufacturing.

The results from the study provide important insights for the management of product development in geographically dispersed settings. The findings emphasize the need to consider potential differences in national culture and language within a product development team. Acknowledging these differences and managing them properly can support efficiency of product development projects.