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Article
Publication date: 1 April 2006

M. Dems, K. Komeza, S. Wiak, T. Stec and M. Kikosicki

To investigate the use of amorphous iron as the stator core material to increase the efficiency of electric machines in serialised production.

Abstract

Purpose

To investigate the use of amorphous iron as the stator core material to increase the efficiency of electric machines in serialised production.

Design/methodology/approach

In the design process of a new structure for the induction motor with a stator core made from amorphous iron it is necessary to apply the circuit method and the field‐circuit method. The use of the circuit method allows quick calculations of many versions of the designed motor, but the use of the field‐circuit method is necessary for verification of the maximal value of the flux density in the entire area of the cross‐sections of the motor core.

Findings

A new construction for the small induction motor with the stator core made from amorphous iron was designed based on the classical structure of the four‐pole induction motor. In the designed motor a decrease of the electric energy costs was observed, which is much bigger than the material costs, and in effect lower total costs for the designed motor were obtained.

Practical implications

According to necessary changes in the motor construction, due to lower saturation limit for this material, the authors obtained a significant increase in the motor efficiency and a decrease in the total cost of the motor. The development of a new technology allows the cutting of amorphous magnetic materials and the production of electric motors from them.

Originality/value

This paper shows the possibility of using amorphous magnetic materials for stator core of small induction machines and the advantages of such construction for obtaining more efficient motor construction.

Details

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

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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

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Article
Publication date: 1 January 1992

K. Komeza, J. Tarocinski and S. Wiak

This paper deals with the field and force calculation in a model electromagnet which is the power drive of the shuttle loom. Hermitian hierarchical finite elements have…

Abstract

This paper deals with the field and force calculation in a model electromagnet which is the power drive of the shuttle loom. Hermitian hierarchical finite elements have been successfully applied to the field and force computation of the electromagnet. The computational results have been reported.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 11 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 January 1994

K. Komeza and S. Wiak

This paper deals with the field and leakage reactance calculations in the model leakage transformer. The approximate solution for 3‐D problem, made by composing 2‐D…

Abstract

This paper deals with the field and leakage reactance calculations in the model leakage transformer. The approximate solution for 3‐D problem, made by composing 2‐D solutions for 3‐D solution, is applied. Hermitian hierarchical finite elements have been successfully applied to the field and reactance computation of the transformer. The computational results have been reported and compared with measurement giving the error not greater than 10%.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 13 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 April 1995

M. Dems, K. Komęza and S. Wiak

Designing of induction motors requires accurate calculation of the field distributions, especially in the case of PWM suppliers. The Finite Element Method (FEM) is useful…

Abstract

Designing of induction motors requires accurate calculation of the field distributions, especially in the case of PWM suppliers. The Finite Element Method (FEM) is useful tool for studying electromagnetic fields in motors, especially for the complicated geometries and nonlinear magnetic properties of such devices.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 14 no. 4
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 2 March 2015

Maria Dems, Krzysztof Komeza, Slawomir Wiak and Sara Fernández Coya

– The purpose of this paper is to present the distribution of the magnetic field and additional losses analysis of the induction motors (IM) with opened and closed rotor slots.

Abstract

Purpose

The purpose of this paper is to present the distribution of the magnetic field and additional losses analysis of the induction motors (IM) with opened and closed rotor slots.

Design/methodology/approach

In the field-circuit approach the distribution and changes of magnetic flux density in the motor are computed using a time-stepping finite element method. The additional losses in each element are evaluated at different frequencies.

Findings

An approximate analytical formulation is derived for rapid losses computation confirmed by the results of field-circuit method. For high-voltage motors due to the size ratios of the core and relatively deep stator and rotor slots major role in causing loss of higher harmonics play a fundamental slot harmonics. Higher harmonics order bigger than 100 cause only small part of total higher harmonics core losses. Closed rotor slots construction influenced significantly on no-load losses mainly due to reduction of losses at slot upper part. For nominal load condition that influence is not so strong according to the saturation of slot tips by rotor leakage flux. Nevertheless, core losses at load are several times higher as at no-load.

Research limitations/implications

In future research authors will take into account motors feed from PWM inverter, working in the frequency range up to 400 Hz.

Practical implications

The results of investigation will be used in more detailed design of IMs especially for motors with closed rotor slots.

Originality/value

The methods presented in the paper was not used before. Also results of additional losses in the motor core calculation, especially according motors with closed slots at no load and load conditions are new.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 34 no. 2
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 24 July 2019

Anna Firych-Nowacka, Krzysztof Smolka and Sławomir Wiak

Electrospinning is a method of the polymer super thin fibres formation by the electrostatic field. The distribution of electrostatic field affects the effectiveness of the…

Abstract

Purpose

Electrospinning is a method of the polymer super thin fibres formation by the electrostatic field. The distribution of electrostatic field affects the effectiveness of the electrospinning.

Design/methodology/approach

This paper presents various computer models that can improve the electrospinning process. The possibilities of modelling the electrostatic field in the design of electrospinning equipment are presented.

Findings

In the research part, the one focussed on finding a cylinder-shaped collector structure to limit the adverse effect of an uneven distribution of the electric field intensity on the collector.

Originality/value

The paper concerns the improvement of the electrospinning process with the use of electrostatic field modelling. In the first part, several possible applications of electrostatic models have been indicated, thanks to which the efficiency of the process has been improved. The original solution of the collector geometry was presented, which according to the authors, in comparison with previous models, gives the most promising results. In this solution, it was possible to obtain an even distribution of the electric field intensity while removing the unfavourable effect of the field strength increase on the outer edges of the collector. The most important aspect in this paper is electric field strength analysis.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 38 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

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Article
Publication date: 11 July 2008

Marcin Lefik and Krzysztof Komęza

This paper aims to present the plan to develop the known algorithm for thermal and electromagnetic coupled problem calculation. This is used for a one‐phase induction…

Abstract

Purpose

This paper aims to present the plan to develop the known algorithm for thermal and electromagnetic coupled problem calculation. This is used for a one‐phase induction motor with locked rotor for nominal and lowered voltage excitation values. It also aims to prepare a calculating method for the average heat transfer coefficient for natural convection from the induction motor housing external face.

Design/methodology/approach

The numerical investigations proposed are based on 3D finite element models for thermal and electromagnetic fields analysis and 3D volume element model for average heat transfer coefficient calculations. The thermal model is experimentally validated.

Findings

The paper provides a numerical method to calculate average heat transfer coefficient for the induction motor housing external faces. This coefficient is shown as a temperature function. Temperature variations in the various parts of the induction motor with locked rotor are calculated. The calculation results are compared with the measurement results.

Research limitations/implications

The average heat transfer coefficient is calculated for a limited range of temperature and for the natural convection case. Electromagnetic field analysis does not include losses in the motor core. These losses could be included in the thermal and electromagnetic fields coupled calculation problem as an additional heat source for the thermal field.

Originality/value

The paper presents a 3D transient thermal field and electromagnetic field coupled problem and proposes a method for calculating the average heat transfer coefficient of natural convection from the housing external face of the induction motor with a locked rotor.

Details

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

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Article
Publication date: 7 September 2012

K.J. Meessen, J.J.H. Paulides and E.A. Lomonova

The purpose of this paper is to present a semi‐analytical modeling technique to describe magnetic fields due to PMs in 3D cylindrical structures. The model is based on 2D…

Abstract

Purpose

The purpose of this paper is to present a semi‐analytical modeling technique to describe magnetic fields due to PMs in 3D cylindrical structures. The model is based on 2D Fourier series and is applied to model the magnetic field of checkerboard magnetization patterns for rotary‐linear actuators.

Design/methodology/approach

The modeling technique based on Fourier series provides a direct solution of the Poisson and Laplace equation by means of separation of variables and is widely used to describe magnetic fields in electromagnetic devices in 2D coordinate systems. In this paper the magnetic scalar potential is used in the Poisson and Laplace equations.

Findings

The magnetic field calculated by the semi‐analytical model is compared with that obtained by Finite Element Modeling and shows excellent agreement. The calculation time of the semi‐analytical model is approximately 60 times shorter than that of finite element analysis.

Research limitations/implications

The method as presented in the paper assumes linear material properties, e.g. the non‐linear B‐H characteristics of iron cannot be taken into account. Furthermore, the structure is assumed to be slotless, that is, stator slots or end‐effects cannot be taken into account.

Practical implications

The semi‐analytical modeling technique is applied to checkerboard magnetization patterns for 2‐DoF actuators in this paper. However, it can be applied to a wide range of slotless cylindrical electromagnetic devices.

Originality/value

As an addition to the common 2D modeling by means of Fourier series, this paper extends the applicability to 3D cylindrical structures. Furthermore, a new checkerboard magnetization is presented which can be used in 2‐DoF rotary linear actuators.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 31 no. 5
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 13 July 2010

Krzysztof Komęza, Xosé M. López‐Fernández and Marcin Lefik

The purpose of this paper is to present the plan to develop the known algorithm for thermal and electromagnetic coupled problem calculation. This is used for three‐phase…

Abstract

Purpose

The purpose of this paper is to present the plan to develop the known algorithm for thermal and electromagnetic coupled problem calculation. This is used for three‐phase induction motor (IM) on nominal load. An additional purpose is verification empiric expressions of the heat transfer and equivalent thermal conductivity coefficients for external faces and air zones in analysed motor taken from literature.

Design/methodology/approach

The numerical investigations proposed in this paper are based on 3D finite element models for thermal and electromagnetic fields analysis. Electromagnetic analysis includes iron core losses. It gives additional heat sources to thermal analysis. Heat transfer and equivalent thermal conductivity coefficients are assessed applying empiric expressions. Thermal model is experimentally validated.

Findings

The results of calculations and experimental test shows that heat transfer coefficient for external zones taken from literature does not guarantee the equal accuracy of the distribution of the temperature in all volume of the machine.

Research limitations/implications

Taken from literature, empirical equations do not give correct values of heat transfer coefficient. It states ways to go further in the evaluation of heat transfer coefficients.

Originality/value

This paper presents modelling methodology of 3D transient thermal field coupled with electromagnetic field applied in three‐phase IM at rated load conditions.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 29 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

1 – 10 of 153