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1

Wpływ wielkości ziarna na właściwości magnetycznie miękkich materiałów kompozytowych

Jastrzębski R., Jakubas A.

Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej

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2017

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Nr 54

109--111

PL

W pracy przeprowadzono analizę wpływu rozmiaru ziarna w magnetycznie miękkich materiałach kompozytowych na ich właściwości magnetyczne. W pracy wykorzystano próbki rdzeni cylindrycznych wykonanych przez autorów z mieszaniny żelaza z polichlorkiem winylu. Badania obejmowały wyznaczenie takich parametrów jak indukcja nasycenia, natężenie koercji i stratność. Zbadano ponadto wpływ częstotliwości magnesowania na stratność materiału.

EN

The application of soft magnetic composites increases in different branch of electric and electronic engineering. For this reason, it is very important to understand the micro-structural effects on their magnetic properties. The paper focuses on the effect of grain size variations of soft magnetic composites on their magnetic properties such as saturation flux density, coercive field strength, power losses etc. During research self-developed materials made of a mixture of pure iron and polyvinyl chloride were used. Three different grain sizes of Fe, namely: up to 50 μm, 50 μm – 100 μm and 100 μm – 150 μm were used in the study. All samples contained 99,5% Fe and 0,5% PVC. The grain size of PVC was 100 μm – 150 μm. The effect of grain size variations on the shape of hysteresis loops was also examined. In the paper it was proved, that the increase of grain size improves magnetic properties of ready-made cores, e.g. the power losses are decreased upon the grain size increase. The aforementioned effect is particularly visible for higher excitation frequencies e.g. at f = 400 Hz.

2

Research on the influence of driving harmonic on electromagnetic field and temperature field of permanent magnet synchronous motor

Qiu H., Yu W., Li Y., Yang C.

Archives of Electrical Engineering

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2017

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Vol. 66, nr 2

295--312

EN

At present, the drivers with different control methods are used in most of permanent magnet synchronous motors (PMSM). A current outputted by a driver contains a large number of harmonics that will cause the PMSM torque ripple, winding heating and rotor temperature rise too large and so on. In this paper, in order to determine the influence of the current harmonics on the motor performance, different harmonic currents were injected into the motor armature. Firstly, in order to study the influence of the current harmonic on the motor magnetic field, a novel decoupling method of the motor magnetic field was proposed. On this basis, the difference of harmonic content in an air gap magnetic field was studied, and the influence of a harmonic current on the air gap flux density was obtained. Secondly, by comparing the fluctuation of the motor torque in the fundamental and different harmonic currents, the influence of harmonic on a motor torque ripple was determined. Then, the influence of different current harmonics on the eddy current loss of the motor was compared and analyzed, and the influence of the drive harmonic on the eddy current loss was obtained. Finally, by using a finite element method (FEM), the motor temperature distribution with different harmonics was obtained.

3

Estimation of power losses in dynamo steel sheets during axial magnetization

Banach A., Mazgaj W., Szular Z.

Przegląd Elektrotechniczny

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2015

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R. 91, nr 12

276-280

EN

Estimation of power losses in dynamo steel sheets during the axial magnetization is still a significant problem. The paper deals with calculations of hysteresis losses and their dependence on the direction of the axial magnetization. Attention was also paid to the power losses caused by “classical” eddy currents, and excess losses which are a result of eddy currents occurring around moving domain walls. Measured power losses of five typical dynamo sheets were compared with results obtained on the basis of analytical formulas.

PL

Określanie strat mocy w blachach prądnicowych jest nadal znaczącym problemem. W artykule omówiono wyznaczanie strat histerezowych i ich zależność od kierunku przemagnesowania osiowego. Zwrócono również uwagę na straty powodowane przez „klasyczne” prądy wirowe oraz straty nadmiarowe, które są skutkiem występowania prądów wirowych wokół przesuwających się ścian domenowych. Zmierzone straty dla pięciu typowych blach prądnicowych porównano z wynikami otrzymanymi na podstawie wzorów analitycznych.

4

The total iron loss determination in the ferromagnetic elements of the electromagnetic speed and torque converter including the magnetization type

Walecki K., Zakrzewski K.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 7a

201-205

EN

In the presented paper the idea and calculation results concerning the total losses in the ferromagnetic parts of electromagnetic torque converter are introduced. Taking advantage of the field calculations it was decided to determine the type of magnetization in the particular regions of converter and evaluate the losses using elliptical hysteresis loop of the materials. The losses calculations were made for the common armature and magnetic wedges in the slots.

PL

Przedstawiono koncepcję i wyniki obliczeń strat w ferromagnetycznych elementach szczególnego przetwornika momentu elektromagnetycznego z uwzględnieniem przemagnesowania płaszczyznowego i osiowego z wykorzystaniem zastępczej histerezy eliptycznej materiałów. W szczególności dokonano obliczenia strat w tworniku i klinach zamykających żłobki twornika.

5

Properties of loss components in electrical steel with Goss texture

Pluta W.

Przegląd Elektrotechniczny

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2009

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R. 85, nr 1

25-27

EN

Samples of non-oriented and grain-oriented electrical steel have been tested in an Epstein frame at three frequencies. The specific total loss was separated into hysteresis, eddy current and excess components. All three of these components are dependent on degree of texture as well as on flux density level. The aim of this paper is to provide a contribution to the understanding of magnetic loss and some properties of its components in soft magnetic materials.

PL

Aparatem Epsteina określono właściwości magnetyczne blach elektrotechnicznych o ziarnie niezorientowanym i zorientowanym dla trzech częstotliwości, a następnie dokonano rozdziału strat na składowe histerezową, wiroprądową i dodatkową. Składowe strat są zależne od stopnia steksturowania jak również od zakresu wartości indukcji magnetycznej. Celem artykułu jest przedstawienie zasadności analizy strat w materiałach magnetycznie miękkich.

6

Local laser marking - new technology in the identification of steel parts

Kalincsák Z., Takács J. G., Sólyomvári K., Göndöcs B., Nagy G. Cs.

Eksploatacja i Niezawodność

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2007

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nr 3

19-22

EN

The importance of identification of machines in the field of maintenance becomes more and more significant. In the field of mechanical maintenance or especially in large-scale production serious difficulties cause to identify various metal parts which have similar form and/or size during technological process. The paper based and printed barcode seemed a safe resolution to this purpose. Unfortunately during the repairing or renewal process the paper based barcodes of steel parts very often were destroyed or damaged, the currently applied paper based and painted codes can cause data losses. This is the fact which indicated the research of steel marking system. In this type of marking the material contains the signs. Other advantage of this system is the readability beneath from painted layer.

7

Rotor power loss in a PM SM by calculation, simulation and measurements, mutual verification of methods

Vannier J. C., Kaczmarek R., Wang Z. Y., Randria A.

Electrical Power Quality and Utilisation. Journal

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2006

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Vol. 12, nr 2

113-116

EN

The subject of the paper is the comparison of four complementary methods of the rotor loss estimation in a PM SM, supplied by a PWM voltage source. An ANSYS based finite element model produces values of W, the magnetic energy stored, and P, the rotor losses. On analytical level the machine is represented by a parallel two elements equivalent circuit for each voltage harmonic. Its parameters are estimated using P and W values. Finally, the eddy current losses representation in the ANSYS code is verified for magnets under study by direct losses measurements. The calculation results are compared with some measured values resulting from analysis and harmonic decomposition of the machine total losses.