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Article
Publication date: 1 June 2000

K. Wiak

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…

Abstract

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.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 19 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 June 2000

A. Savini

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic…

1040

Abstract

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 19 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 11 November 2013

Sebastian Schöps, Herbert De Gersem and Thomas Weiland

The purpose of this paper is to review the mutual coupling of electromagnetic fields in the magnetic vector potential formulation with electric circuits in terms of…

Abstract

Purpose

The purpose of this paper is to review the mutual coupling of electromagnetic fields in the magnetic vector potential formulation with electric circuits in terms of (modified) nodal and loop analyses. It aims for an unified and generic notation.

Design/methodology/approach

The coupled formulation is derived rigorously using the concept of winding functions. Strong and weak coupling approaches are proposed and examples are given. Discretization methods of the partial differential equations and in particular the winding functions are discussed. Reasons for instabilities in the numerical time domain simulation of the coupled formulation are presented using results from differential-algebraic-index analysis.

Findings

This paper establishes a unified notation for different conductor models, e.g. solid, stranded and foil conductors and shows their structural equivalence. The structural information explains numerical instabilities in the case of current excitation.

Originality/value

The presentation of winding functions allows to generically describe the coupling, embed the circuit equations into the de Rham complex and visualize them by Tonti diagrams. This is of value for scientists interested in differential geometry and engineers that work in the field of numerical simulation of field-circuit coupled problems.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 32 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 10 April 2007

G.B. Kumbhar, S.V. Kulkarni, R. Escarela‐Perez and E. Campero‐Littlewood

This paper aims to give a perspective about the variety of techniques which are available and are being further developed in the area of coupled field formulations, with…

1186

Abstract

Purpose

This paper aims to give a perspective about the variety of techniques which are available and are being further developed in the area of coupled field formulations, with selective bibliography and practical examples, to help postgraduate students, researchers and designers working in design or analysis of electrical machinery.

Design/methodology/approach

This paper reviews the recent trends in coupled field formulations. The use of these formulations for designing and non‐destructive testing of electrical machinery is described, followed by their classifications, solutions and applications. Their advantages and shortcomings are discussed.

Findings

The paper gives an overview of research, development and applications of coupled field formulations for electrical machinery based on more than 160 references. All landmark papers are classified. Practical engineering case studies are given which illustrate wide applicability of coupled field formulations.

Research limitations/implications

Problems which continue to pose challenges to researchers are enumerated and the advantages of using the coupled‐field formulation are pointed out.

Practical implications

This paper gives a detailed description of the application of the coupled field formulation method to the analysis of problems that are present in different electrical machines. Examples of analysis of generators and transformers with this formulation are presented. The application examples give guidelines for its use in other analyses.

Originality/value

The coupled‐field formulation is used in the analysis of rotational machines and transformers where reference data are available and comparisons with other methods are performed and the advantages are justified. This paper serves as a guide for the ongoing research on coupled problems in electrical machinery.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 26 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 10 May 2011

Grzegorz Utrata and Andrzej Kaplon

The aim of the paper is to present the methodology of obtaining an approximate equivalent circuit composed of lumped parameters which describes an electromagnetic state of…

Abstract

Purpose

The aim of the paper is to present the methodology of obtaining an approximate equivalent circuit composed of lumped parameters which describes an electromagnetic state of induction machines (IMs) with solid secondary. Higher space harmonic field components are taken into account. The proposed method of machine model constructing is useful for solving electrodynamics states of solid secondary IMs, as well linear machines.

Design/methodology/approach

A determination of equivalent circuit parameters of a polyharmonic machine is divided into two steps. In the first step, frequency plots of the spectral inductances are derived – for each of the space harmonic components – from an electromagnetic field distribution calculated by means of the finite element method. In the second step, each of the spectral inductances are represented by the operational inductances which corresponds to the equivalent circuit composed of parallel connected the magnetizing inductance and branches consisting of resistance and inductance connected in series.

Findings

The proposed method allows the construction of the approximate equivalent circuit with lumped parameters which enables to solve electrodynamic states of solid secondary IMs, as well linear machines. The machine model has been derived with consideration of the higher space harmonic field components.

Research limitations/implications

Saturation effects of a magnetic circuit and an unbalance of phase currents have not been taken into account.

Originality/value

The paper shows the method of constructing a machine fieldcircuit model. Lumped parameters of the model have been derived using frequency characteristics of the stator spectral inductance with consideration of the higher space harmonic field components.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 30 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 5 January 2010

Andrzej Demenko and Kay Hameyer

The purpose of this paper is to develop and systemize the 3D finite element (FE) description of electromagnetic field in electrical machines.

Abstract

Purpose

The purpose of this paper is to develop and systemize the 3D finite element (FE) description of electromagnetic field in electrical machines.

Design/methodology/approach

3D FE models of electrical machines are considered. The model consists of FE equations for the magnetic field, equations describing eddy currents and equations, which describe the currents in the machine windings. The FE equations are further coupled by the electromagnetic torque to the differential equation of motion. In the presented fieldcircuit model, the flux linkages with the windings are expressed by two components. Attention is paid to the description of machine winding. Both scalar and vector potential formulations are analysed. The FE equations are derived by using the notation of circuit theory. The methods of movement simulation and torque calculation in FE models are discussed.

Findings

Proposed circuit description of electromagnetic field in electrical machines conforms to the applied method of electric and magnetic circuit analysis. The advantage of the presented description is that the equations of field model can be easy associated with the other equations of the electric drive system.

Originality/value

The applied analogies between the FE formulation and the equivalent magnetic and electric network models help formulate efficient field models of electrical machines. The developed models after coupling to the models of supply and control system can be successfully used in the analysis and design electric drives.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 29 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 26 January 2022

Manuele Bertoluzzo, Paolo Di Barba, Michele Forzan, Maria Evelina Mognaschi and Elisabetta Sieni

The paper aims to propose a a field-circuit method for investigating the magnetic behavior of a wireless power transfer system (WPTS) for the charge of batteries of…

Abstract

Purpose

The paper aims to propose a a field-circuit method for investigating the magnetic behavior of a wireless power transfer system (WPTS) for the charge of batteries of electric vehicles. In particular, a 3D model for finite element analysis (FEA) for the field simulation of a WPTS is developed. Specifically, the effects of aluminum shield and steel layer, representing the car frame, on the self and mutual inductances are investigated. An equivalent electric circuit is then built, and the relevant lumped parameters are identified by means of the FEAs.

Design/methodology/approach

The finite element model is used to evaluate self and mutual inductances in several transmitting-receiving coil configurations and relative positions. In particular, the FEA simulates the aluminum and steel layers as shell elements in a 3D domain. The self and mutual inductance values in the aligned coil case are also used as input parameters in a circuit model to evaluate the onload current.

Findings

The use of shell elements in FEA substantially reduces the number of mesh elements needed to simulate the eddy currents in the steel and aluminum layer, so putting the ground for low-cost field analysis. Moreover, the FEA gives an accurate computation of the self and mutual inductance to be used in a circuit model, which, in turn, provides a fast update of the onload induced current.

Originality/value

To save computational time, the use of 2D shell elements to model thin conductive regions introduces a simplified FEA that could be used in the WPTS simulation. Moreover, the dynamic behavior of WPTS, i.e. the operation when the receiving coil is moving with respect to the transmitting one, is considered. Because of the lumped parameters’ dependence upon the relative positions of the two coils, the proposed method allows identifying the circuit parameters for several configurations so substantially reducing the computational burden.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 April 2006

S. Kanerva and A. Arkkio

To provide a general method for coupled simulation of electrical machines and circuits, using finite element analysis and a circuit/system simulator.

Abstract

Purpose

To provide a general method for coupled simulation of electrical machines and circuits, using finite element analysis and a circuit/system simulator.

Design/methodology/approach

The electrical machine is modelled by dynamic inductance and electromotive force (EMF), which are determined by finite element analysis and updated in time‐stepping procedure. Calculation of these parameters is based on current perturbations that are applied on linearized field equations after determining the operating point by nonlinear analysis.

Findings

Based on the case studies, the presented method can be utilized in coupled fieldcircuit simulation and the results correlate with those obtained by other known methods. The results were also validated according to experimental data.

Research limitations/implications

Calculation of the EMF and the presented implementation for SIMULINK have some limitations regarding the accuracy and stability of the numerical integration. In the future, the numerical methods could be still improved and the implementations could be extended to other simulators.

Practical implications

Since the presented methodology is of a general type, the research provides means to include fieldcircuit coupling into a variety of different simulation software.

Originality/value

Definitions of the circuit parameters differ from the conventional ones, as a result of which the parameter extraction can be performed in computation‐effective way. The benefits of the research are met widely, since the general‐purpose methodology is not limited to any single software.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 25 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 11 July 2008

Renata Sulima and Slawomir Wiak

The main aim of this paper is to build an equivalent circuit model of a comb drive microactuator, while the phenomenon of generating the electric fringing field at…

Abstract

Purpose

The main aim of this paper is to build an equivalent circuit model of a comb drive microactuator, while the phenomenon of generating the electric fringing field at electrode edges is taken into consideration.

Design/methodology/approach

The approach to the comb drives design requires the “leakage capacitance” (appearing at electrode edges) to be introduced to the complex equivalent circuit model. Introducing these capacitances leads to defining the circuit model properly.

Findings

Such a complex approach by use of the equivalent circuits model could make it possible to reduce the discrepancy between the field and circuit models. These results were obtained after comparing both field and circuit models.

Originality/value

MEMS microdrives are in the area which is being developed very dynamically. Improvements in the mathematical models would permit more precise microdrive design, leading to optimal structure.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 27 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 19 June 2007

Saku Suuriniemi, Jari Kangas and Lauri Kettunen

The paper addresses various ways of driving a magneto‐quasi‐static coupled fieldcircuit problems, starting with the underlying assumptions of this problem class. It…

Abstract

Purpose

The paper addresses various ways of driving a magneto‐quasi‐static coupled fieldcircuit problems, starting with the underlying assumptions of this problem class. It focuses on problem consistency, supporting both conceptual understanding, and translation into software.

Design/methodology/approach

The paper proceeds from a precisely defined problem class and analyze its consistency with homology theory.

Findings

Precise notion of “driving a problem,” extensive discussion of modeling assumptions and decisions, and classification and consistency analysis of various driving methods.

Practical implications

Helps modelers systematically pose consistent coupled fieldcircuit problems. The computation of homology groups can be automated to help pose problems and detect consistency problems.

Originality/value

Starting from the basic underlying assumptions, the paper summarizes logically the application of homology to consistency analysis. The style is tutorial for modelers, with numerous particular cases.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 26 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

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