
M. Bugeza and R. Fišer
:
2D numerical model of electromagnetic structures for educational purposes

M. Bugeza, R. Fišer and S. Ferkolj
:
Calculation of linear induction motor performance using finite element method

W. Burlikowski and K. Kluszczyński
:
An analytical field model of a squirrel cage induction motor: experimental verification

K. Ciosk
:
Calculation of electromagnetic field in a disktype induction motor
using a 3D reluctance network method

H. De Gersem and K. Hameyer
:
Motional finite element simulation of magnetic brakes and solid rotor induction machines

R. Fišer and S. Ferkolj
:
The application of the finite element method in diagnostics of electrical drives

V. Goričan, A. Hamler, B. Hribernik, M. Jesenik and M. Trlep
:
Measurement setup for 1D and 2D testing of magnetic properties of
magnetic steel sheets

M. Jesenik, V. Goričan, M. Trlep, A. Hamler and B. Štumberger
:
Eddy current calculation in the circular sample of the
twophase rotational single sheet tester

A. Krawczyk and R. Kotowski
:
Some introductory remarks on modeling of the electromagnetic phenomena

D. Križaj and V. Valenčič
:
AC current conduction in biological tissues

A. Kwiatkowska, A. Krawczyk and J. Sikora
:
Material derivative technique in optimal design

D. Miljavec and S. Knez
:
Newly redesigned magnetic head for wire rope NDT

K. Pawluk
:
Magnetostatic field distribution due to inherent magnetisation of permanent magnets

B. Polajžer, D. Dolinar, G. Štumberger and K. Hameyer
:
Force calculation of the laboratory implementation of a radial
active magnetic bearing

P. Puternicki and R. Sulima
:
Userfriendly system PROJMAT 2001 for deterministic optimisation
of small commutator motors

J. Rozman, M. Trlep, B. Zorko and M. Bunc
:
Stimulation of nerves innervating the pancreas of a dog

T.J. Sobczyk
:
Interaction of saturation of magnetic circuits for the main and
leakage fluxes in induction machines

Ž. Štih, Z. Haznadar, M. Topolnik and S. Berberović
:
Modelling of currentlimiting circuit breakers

B. Štumberger, A. Hamler, M. Jesenik, V. Goričan and M. Trlep
:
Fluxweakening and output power capability estimation
of interior permanent magnet synchronous motor in variable speed
drive applications

I. Tičar, D. Ružič, K. Preis and O. Bíró
:
Simulation of a high frequency electromagnetic field using the TEM
propagation mode method

S. Wiak, P. Drzymała and H. Welfle
:
Electromagnetic field analysis of 2D3D structure
of switched reluctance motors (disctype)

S. Wiak, P. Drzymała and H. Welfle
:
Comparative study of shunt reactor structures by field models

I. Zagradišnik and B. Slemnik
:
Rotating field in induction motor under consideration of anisotropy
and cutting strains of steel sheets

H.K. Lachowicz, K. Závěta and A. ŚlawskaWaniewska
:
Partially devitrified metallic glasses

T. Zyss, A. Zięba and A. Krawczyk
:
Electricity of electroconvulsive therapy

M. Bugeza and R. Fišer
:
2D numerical model of electromagnetic structures for educational purposes

The paper presents the development of a software package
for static and timevariable magnetic field calculations in 2D
electromagnetic structures for educational purposes. It has a
simple and clear structure in order to assure students a simple
tool for studying electromagnetic fields. It enables the
stepbystep insight into the procedure of the preprocessor,
structure of the solvers and representation of the results. The
computational results are also compared with other FEM packages
and have proved to be of a significant practical value in the
postgraduate courses.
Contents

M. Bugeza, R. Fišer and S. Ferkolj
:
Calculation of linear induction motor performance using finite element method

The paper presents the calculation of a linear induction
motor steadystate and dynamic characteristics using the finite
element method. The 2D nonlinear eddycurrent solver was used for
magnetic field and force calculations. Quantities like magnetic
vector potential, flux density, force components, primary and
secondary currents, mutual and leakage inductance, can be
determined very precisely. The detailed insight in magnetic field
distribution of a linear induction motor forms the basis for
evaluation of its operational behaviour. The results obtained by
the finite element method are further used in the process of the
mathematical modelling and control simulation based on the space
vector theory.
Contents

W. Burlikowski and K. Kluszczyński
:
An analytical field model of a squirrel cage induction motor: experimental verification

The paper presents the results of experimental
verification of an analytical field model of a squirrel cage
induction motor. Basic properties of the model are presented.
Methods employed in the measurement are described. The obtained
torque measurement data are compared with the simulation results
for a selected machine prototype.
Contents

K. Ciosk
:
Calculation of electromagnetic field in a disktype induction motor
using a 3D reluctance network method

The paper presents an analysis of the magnetic field in
a disktype induction motor with doublesided stator and twin
rotors. The magnetic flux density was found in a 3D space using
the reluctance network method (RNM). The results were compared
with the measurements carried out on the real object.
Contents

H. De Gersem and K. Hameyer
:
Motional finite element simulation of magnetic brakes and solid rotor induction machines

The torques of a magnetic brake and a solid rotor
induction machine, fed by sinusoidal voltage sources, are
simulated by a motional finite element method. Oscillatory
solutions occurring for motional models with elevated velocities,
are prevented by adaptive mesh refinement relying upon
intermediate solutions stabilised by upwinded finite element test
functions. A relaxed successive approximation deals with the
nonlinear material properties. The connections of the conductors
and windings within the finite element model to external loads,
impedances and supplies are represented by an electric circuit and
added to the system of equations. The technical examples indicate
the advantages of the motional formulation.
Contents

R. Fišer and S. Ferkolj
:
The application of the finite element method in diagnostics of electrical drives

The paper presents the application of the finite element
method for predicting the performance of induction motor having
asymmetry of stator and/or rotor winding due to the different
combination and propagation of faults gained during heavyduty
operation. Quantities like magnetic vector potential, flux
density, force components, rotor and stator currents, mutual and
leakage inductance are determined very precisely. The detailed
insight in magnetic field distribution of a squirrel cage
induction motor, forms the basis for further evaluation of its
operational behaviour. Increasing anomaly in magnetic field
distribution due to the increasing stage of faults propagation
results in a degradation of steadystate and dynamic performance
of the induction motor and can be evaluated with computer
simulation eliminating expensive and timeconsuming laboratory
tests.
Contents

V. Goričan, A. Hamler, B. Hribernik, M. Jesenik and M. Trlep
:
Measurement setup for 1D and 2D testing of magnetic properties of
magnetic steel sheets

In electrical machines core loss is caused not only by
alternating but also by rotational magnetic fields. Therefore the
interest in 2D measurement of magnetic properties of magnetic
steel sheets in rotational magnetic field increases. The round
rotational single sheet tester (RRSST) for circular samples is
presented. Special attention is paid to achieve a greater
measuring region and the equality of field distribution in the
sample for all magnetisation directions. The completely automated
measuring setup allows the measurements in alternating, pure
rotational, elliptical and also in distorted rotating magnetic
field. The field metric measuring technique was used.
Contents

M. Jesenik, V. Goričan, M. Trlep, A. Hamler and B. Štumberger
:
Eddy current calculation in the circular sample of the
twophase rotational single sheet tester

Round rotational single sheet tester (R.R.S.S.T.) is
used for the measurement of magnetic properties in rotational and
alternating magnetic fields. The homogeneity of the magnetic field
and the influence of eddy currents on the homogeneity of the
magnetic field distribution in the circular sample are
investigated. Results of the calculation are compared with results
of the measurements.
Contents

A. Krawczyk and R. Kotowski
:
Some introductory remarks on modeling of the electromagnetic phenomena

Cum Deum calculat, fit mundus.
G.W. Leibniz
Everything should be made as simple as possible but not simpler.
A. Einstein
Contents

D. Križaj and V. Valenčič
:
AC current conduction in biological tissues

Electrical properties and structure of biological tissue
determine the manner of current conduction through them. Numerical
simulation of a cell suspension is performed demonstrating the
effect of frequencydependent effective specific conductivity and
permittivity. For AC current conduction, magnetic induction
effects can be neglected in a wide frequency range. Displacement
current is in general smaller than conductive, however, for proper
analysis it cannot be completely neglected.
Contents

A. Kwiatkowska, A. Krawczyk and J. Sikora
:
Material derivative technique in optimal design

The paper deals with the problem of shape design, and
the shape has to ensure the assumed distribution of the function.
The concept of material (substantial) derivative has been employed
in order to solve the problem. The numerical model was based on
the Finite Element Analysis. The quoted results show that the
method of optimisation is effective for the problem of shape
design.
Contents

D. Miljavec and S. Knez
:
Newly redesigned magnetic head for wire rope NDT

The aim of the present paper is to analyse a newly
redesigned magnetic head. Basic use of this head is in
nondestructive testing (NDT) of wire ropes. The magnetic head
system is composed of two main areas and three main parts. These
areas are: magnetic flux leakage area in central region, and eddy
current magnetic field area in outer side region of magnetic head.
The analyses were carried out by analytic approach and by the
finite element method. The value of induced voltage in flux
leakage pickup coils was calculated by axisymmetric 2D
magnetostatic finite element analysis made by ferromagnetic rod to
simulate the wire rope. Meanwhile, voltage induced by changes in
eddy current magnetic field was calculated by a 2D transient
linear motion finite element analysis. All numerically calculated
results were compared with the measured ones on a geometrically
similar ferromagnetic rod. Also, we have presented the measured
results carried out by newly redesigned magnetic head on real
steel wire rope with anomalies.
Contents

K. Pawluk
:
Magnetostatic field distribution due to inherent magnetisation of permanent magnets

A boundaryintegral model of the static magnetic field
due to cylindrical permanent magnets that is put in free space is
considered. Magnetic scalar potential quantities created by a
virtual quantity "surface magnetic charge density" is expressed
by means of LipschitzHankel integrals that for the considered
case are reducible (by the way of hypergeometric series) to some
algebraic expressions, in which elliptic integrals of various
kinds occur. This approach seems to be more effective than that
can be reached by the use of a typical professional software for
the field problems in which numerical integration, being not quite
conform to the considered case, is common. The magnet subjected to
the analysis has to be virtually subdivided in some number of
elementary pieces, inside of which the uniform distribution of the
inherent magnetization is supposed.
Contents

B. Polajžer, D. Dolinar, G. Štumberger and K. Hameyer
:
Force calculation of the laboratory implementation of a radial
active magnetic bearing

Performances of the controlled active magnetic bearings
can be sufficiently improved with the exact knowledge of the
bearing force in the entire operating range. Therefore the
magnetic force calculation of the laboratory implementation of a
radial magnetic bearing, using 2D finite element method, is
presented in the paper. Two methods for the force calculation are
used, where both, i.e. the Maxwell stress tensor method and the
virtual work method, give very close results. The verification of
the bearing force calculation is performed by their comparison
with measurements. The obtained results make it possible to
perform a robust control design in the entire operating range.
Contents

P. Puternicki and R. Sulima
:
Userfriendly system PROJMAT 2001 for deterministic optimisation
of small commutator motors

System PROJMAT 2001 is used for designing small
commutator motors. The software in the Matlab 5.0 and the Toolbox
Optimisation is used for multicriterial optimisation. The software
has an interface which is constructed of elements and functions in
the Uitools package of the Matlab. The interface is build on the
basis of a series of windows which enables the data segregation
and communication with the user. It gives a possibility of an easy
and comprehensible preparation of all input technical data and
constraints. The main parts of the system are: the optimisation
block, the postprocessor block and controlling over them the
interface block. The example of small motor design is given in
this paper.
Contents

J. Rozman, M. Trlep, B. Zorko and M. Bunc
:
Stimulation of nerves innervating the pancreas of a dog

The purpose of the study was to evaluate the influence
of electrical stimulation of nerves innervating the pancreas on
the function of the cardiovascular system, lungs and urinary
tract, measured as an ECG, blood pressure and pressure in the
bladder of a dog. Spiral cuffs with 33 electrodes (1.0×2.0mm)
within a silicone sheet were manufactured and implanted in a
Beagle dog in the vagus nerve, in the splanchnic nerve and in the
pancreatic nerve. Each nerve was stimulated individually with
biphasic, rectangular and current pulses (10mA, 200μs,
20Hz). When stimuli were 10mA or higher, measurable changes were
observed during stimulation of both the vagus and the splanchnic
nerves. In the splanchnic nerve, they were expressed as an
increase in pressure in the bladder and as a tremor of the whole
stomach. In the vagus nerve, they were expressed as a drastic
decrease of arterial blood pressure and as abnormalities in the
heart rate. In a further increase of stimuli to about 18mA, the
heart rate was slowed until it ceased as fatal brachicardia,
asystolia and consequently hypotensia was occured.
Contents

T.J. Sobczyk
:
Interaction of saturation of magnetic circuits for the main and
leakage fluxes in induction machines

The paper presents a model of induction machines, in
which saturation for both the main and leakage fluxes of
individual windings is represented. The model operates with the
real winding currents what gives a chance to model saturation of
leakage magnetic circuits separately for each winding. The
saturation of the main magnetic circuit is modelled by introducing
a magnetising current defined analytically by all machine
currents. Such a model allows to study the interaction of
saturation of separately treated magnetic circuits of the main and
leakage fluxes. Remarkable results of simulations are shown in the
paper.
Contents

Ž. Štih, Z. Haznadar, M. Topolnik and S. Berberović
:
Modelling of currentlimiting circuit breakers

A circuit model of currentlimiting circuit breakers
that enables the simulation of the limiting process as well as the
analysis of the parameters of transient phenomena is described.
The model consists of a system of nonlinear timedependent
differential equations that has to be coupled to the numerical
solution of the magnetic field in the contact space. Reliability
of such breakers highly depends upon the actuator in the tripping
system. The modelling of the dynamic response of the actuator is
based on the response surface methodology and on the lumped
parameter time domain simulation of response of actuator to a
voltage pulse. The results of the simulations are compared with
measurements.
Contents

B. Štumberger, A. Hamler, M. Jesenik, V. Goričan and M. Trlep
:
Fluxweakening and output power capability estimation
of interior permanent magnet synchronous motor in variable speed
drive applications

Fluxweakening and output power capability estimation of
the fourpole interior permanent magnet synchronous motor (IPMSM)
determined from the finite element method (FEM) analysis of
magnetic conditions is presented. The influence of the iron loss
on the output power capability (OPC) and the constantpower speed
range (CPSR) of the tested IPMSM is included in the analysis by
the posterior iron loss calculation. Results of the calculations
are partially verified by the measurements.
Contents

I. Tičar, D. Ružič, K. Preis and O. Bíró
:
Simulation of a high frequency electromagnetic field using the TEM
propagation mode method

Much has been written about the possible health hazards
of electromagnetic fields (EMFs). Consumers are bombarded with
quasiscientific reports, many of which are more confusing than
accurate. This paper presents a project undertaken to evaluate
high frequency electromagnetic fields using a TEM mode, the
propagation mode calculation method followed by confirmation of
any doubts about field levels using onsite measurements. An
electromagnetic field can be monitored through all stages from the
design to the operational state of the radiation source because of
the use of both possible evaluation methods (calculation and
measurements).
Contents

S. Wiak, P. Drzymała and H. Welfle
:
Electromagnetic field analysis of 2D3D structure
of switched reluctance motors (disctype)

In the paper comparative studies of 2D3D disctype
Switched Reluctance Motor (SRM) structures are performed. The
calculation of magnetic field distributions and the static torque
characteristics have been computed by means of Finite Element
Method (FEM) for 2D and 3D motor structures. It has been
emphasized that the calculations of the model structure (thanks to
axial symmetry) have been done for a half of the volume while the
boundary conditions are predefined. 3D structure of the model
motor is built up, then the mesh is generated for number of
elements exceeding 100000. The results of 3D calculations are
presented in the form of the static torque characteristics and
magnetic flux curves versus rotor angular positions and current
densities in the stator winding as well. Disctype SR motors
thanks to their specific structures are commonly used in
automotive system, servodrives, etc. The motor structure consists
of the stator core toroidally shaped in which slots are placed on
both sides of the active surface; moreover stator windings are
wounded as Gramma type (made of identical coils surrounding the
stator core). SRM are proposed to be mounted at the wheel of
gearless electric vehicles (small cars, wheelchair, scooters,
etc.).
Contents

S. Wiak, P. Drzymała and H. Welfle
:
Comparative study of shunt reactor structures by field models

The paper presents the results of field analysis of the
shunt reactor 3D structure based on a field method. The magnetic
field computations have been carried out for the shelltype and
twolimb structure of a onephase shunt reactor, then to be
assembled as a 3phase unit. The field calculations are performed
for 3D model reactor structures with different number of core
slices (different number of air gaps, but with constant
intermediate  slice air gap length). The 3D structure of the
model reactor is built up, then the mesh is generated for a number
of elements exceeding 200000. The optimal value of the ratio d/g
(height of the intermediateslice air gap/height of the limb
slice) and the ratio d/g (height of the intermediateslice air
gap/diameter of the limb) are evaluated leading to minimum values
of the weight and capitalized cost of the device.
Contents

I. Zagradišnik and B. Slemnik
:
Rotating field in induction motor under consideration of anisotropy
and cutting strains of steel sheets

The rotating magnetic field in a symmetrical induction
machine supplied with a sineshaped and balanced system shows an
asymmetrical shape if the magnetic medium is anisotropic. The
shape of the air gap magnetic flux distribution is repeated twice
per one revolution of the rotating field in a twopole machine.
The harmonic analyses show that all components rotate with
variable magnitudes and nonuniform speeds. The variations are
greater if the order of the component is higher. Only odd
harmonics occur. Due to the spatial dependence of reluctance and
the electric voltage balance in an induction machine, the
magnetizing current also shows a spatial dependence.
Contents

H.K. Lachowicz, K. Závěta and A. ŚlawskaWaniewska
:
Partially devitrified metallic glasses

Ábiit non óbiit.
The paper presents a review of selected experiments which have
been carried out using partially devitrified Fe and Cobased
metallic glasses as the research objects. It is shown that by a
suitable choice of the composition of the metallic glass and also
by the conditions of annealing, a variety of magnetic phases can
be created in these systems. It is also shown that by controlled
processes of annealing, the coercivity of metallic glass can be
altered by several orders of magnitude, giving a possibility to
produce materials with the extremely soft magnetic properties, up
to the magnetically semihard ones. The magnetostriction of
nanocrystalline materials of the FINEMETtype is discussed as
well, showing that the sizedependent phenomena and the symmetry
restriction at the particle boundaries create the surface
contribution to the effective magnetostriction. Finally, the
magnetic interactions between particles in partially devitrified
samples are considered and the observed effects of temperature and
hydrostatic pressure discussed.
Contents

T. Zyss, A. Zięba and A. Krawczyk
:
Electricity of electroconvulsive therapy

This paper describes physiological phenomena of a
electrical stimulation of nerve cell and presents technical issues
of electroconvulsive therapy used by psychiatrists.
Contents
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