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Tytuł:
Fast control of the six phase asymmetric generator with the 3rd harmonic current injection
Autorzy:
Gołębiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/141252.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
6-phase asymmetric generator
third harmonic current injection
control trajectories
MTPA
MTPF
Opis:
In this paper the MTPA, MTPF, constant torque and constant flux control trajectories are presented. These trajectories are calculated for a 6-phase asymmetric insettype SMPMSM generator with the assumption of a certain level of 3rd harmonic current injection. This injection technique increases the generator performance due to the cooperation of the fundamental and 3rd harmonic. The presented trajectories are used for fast control of the generator working in the gearless wind turbine system.
Źródło:
Archives of Electrical Engineering; 2016, 65, 1; 59-71
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improvement of the finite element method equations conditioning for the magnetic field-circuital problems
Autorzy:
Gołębiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/141457.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
magnetic field-circuital problem
condition number
iterative method
Opis:
The presented systems with magnetically coupled windings are solved with the finite element method. If the issue of voltage supply is analyzed, a system of linear equations with a partially skew-symmetric sparse matrix is obtained. Iterative methods used to solve a system of equations are particularly effective for symmetric matrices. Resultant equations can be reduced to this symmetrical form by using the method known from the literature [1]. The ratio of the maximum to the minimum eigenvalue of the main matrix of this circuit, which is the condition number, is however very high. This means that the problem is ill-conditioned and leads to a very long iterative solution process. The method presented in the article allows for a direct solution of a system of equations on its part, corresponding to high eigenvalues of the system matrix. The remaining part of the system of equations is solved by iterative methods. This part has much better condition number, and therefore the computational process is fast. The proposed iterative process depends on multiplication of a sparse matrix by vectors. It is not necessary (and possible) to store the entire matrix. This is especially important for larger sizes of a matrix.
Źródło:
Archives of Electrical Engineering; 2017, 66, 2; 325-337
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optymalne sterowanie kilku falowników przy ich równoległej pracy na sieć autonomiczną
Optimal controling of the several inverters during their parallel operation for autonomous grid
Autorzy:
Gołębiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1369605.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Napędów i Maszyn Elektrycznych Komel
Tematy:
optymalne sterowanie
sieć autonomiczna
optimal controling
autonomous grid
Opis:
Cooperation of the several inverters systems differing in parameters were considered. All inverters are connected to the common load. The load is impedance of the inductance type in star layout. Parallel with the star of load, the star of capacity is connected. The goal of the circuit is to create the symmetric layout of the 3-phase voltages at the load, which is asymmetric and can have impulse characteristic. The measurements of the voltages in autonomous grid at real object and measurements of the currents flowing from etery circuit to the load were taken. The controlled magnitude are currents flowing from the inverters for which the optima value is calculated. We need to take into account the limitation of maximum allowed value of this current. The system of inverters, connected parallel, can have tendency to oscillation. It manifests by presence of the high er ripples in inverters currents. These pulsations actually compensate each other, they are not noticeable at the load site and give needed load current. This phenomenon is a kind of resonance pulsation, it consists of transfer ring the power (even negative) between individual inverters and that is why it is very bad.
Źródło:
Maszyny Elektryczne: zeszyty problemowe; 2012, 2, 95; 7-11
0239-3646
2084-5618
Pojawia się w:
Maszyny Elektryczne: zeszyty problemowe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model dwustanowy prognozowania wydajności turbiny wiatrowej
Two state prediction model of wind turbine efficiency
Autorzy:
Gołębiowski, M.
Mazur, D.
Powiązania:
https://bibliotekanauki.pl/articles/153877.pdf
Data publikacji:
2013
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
turbina wiatrowa
modele Markowa
prognozowanie
wind turbine
Markov model
prediction
Opis:
W artykule przedstawione zostały modele markowa prognozowania wydajności turbiny wiatrowej zależnej od wiejącego wiatru. Prognozowanie wydajności turbiny można oprzeć nawet na prostym modelu dwustanowym. Dobór parametrów modelu dwustanowego pozwala na określenie, jaka jest w ciągu stanów pracy turbiny średnia długość ciągów tego samego typu. W artykule przedstawiona została metoda prognozowania wydajności pracy turbiny wiatrowej oparta na niejawnych łańcuchach Markowa. Zaproponowane w pracy podejście oparte jest na dwóch twierdzeniach związanych z algorytmem przód-tył oraz algorytmem Bauma-Welcha.
This paper presents the Markov model of the wind turbine efficiency prediction. As the share of wind generated energy in total energy production constantly increases, the precise prediction of the wind turbine efficiency has become an important issue. The prediction of the efficiency of the wind turbine can be based on a simple, two state, model. In this model state A represents the high efficiency operation and state B the low efficiency operation of the wind turbine. The quality of this model is investigated. The two state model parameter recognition allows determination of the average duration of the sequence of states of the same type. The presented method is based on implicit Markov chains. The proposed approach is based on two, well known, algorithms. The forward-backward and Baum-Welch algorithms are used. The investigated method is an alternative to a commonly used method based on the wind velocity and direction measurements and the Weibull distribution of wind speed. Since these measurements are taken at the altitude of 10m this method is inaccurate.
Źródło:
Pomiary Automatyka Kontrola; 2013, R. 59, nr 10, 10; 1070-1072
0032-4140
Pojawia się w:
Pomiary Automatyka Kontrola
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calculating the main and leakage inductance matrix of the 3-column 15-winding autotransformer
Autorzy:
Mazur, D.
Gołębiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/141045.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
autotransformator
indukcyjność rozproszenia
straty wiroprądowe
efekt zbliżenia
autotransformer
leakage inductance
eddy current losses
proximity effect
Opis:
The aim of this paper is presentation and comparison of calculation methods of the inductance matrix of a 3-column multi-winding autotransformer. Main and leakage autotransformer inductance was obtained using finite elements method. Static calculations were made at the current supply for 2D and 3D models, and mono-harmonic calculations were made at the voltage supply. In the mono-harmonic calculations the eddy current losses were taken into account, this made it possible to study relationship between the autotransformer parameters and the frequency. Calculations were made using Ansys and the authors' own programs in Matlab.
Źródło:
Archives of Electrical Engineering; 2011, 60, 3; 215-222
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Measurement and calculation of 3-column 15-winding autotransformer
Autorzy:
Mazur, D.
Gołębiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/141055.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
autotransformator
indukcyjność rozproszenia
straty wiroprądowe
efekt zbliżenia
autotransformer
leakage inductance
eddy current losses
proximity effect
Opis:
The 15-winding and 3-column autotransformer supplying an 18-pulse rectifier circuit was developed. Presented methods can be used also for the autotransformers of other topologies supplying different kinds of converters. Presented methods make it possible to exactly calculate main and leakage inductances of the multi-winding autotransformer. The presented analysis of the eigenvalues and eigenvectors of the inductance matrix makes it possible to identify the influence nature of individual modes on the inductance matrix, and to compare the calculation results obtained using the presented methods. Frequency dependence of autotransformer parameters was shown. Also modes of the impedance matrix of the multi-winding autotransformer was investigated, this made it possible to identify the influence nature of individual modes on the inductance matrix. Using presented methods one can exactly calculate main and leakage inductances of the autotransformer. Thanks to this, one can design in optimal way autotransformers for supplying, for example, rectifier circuits, THD coefficients. The results of the measurements and simulations were also shortly presented at the end of the article.
Źródło:
Archives of Electrical Engineering; 2011, 60, 3; 223-230
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Seasonality study of extracts from leaves of Thuja occidentalis L.
Autorzy:
Chajduk, M.
Gołębiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/2142057.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
extract
GC-MS
Thuja occidentalis
volatile compounds
Opis:
The market value of essential oils is steadily increasing every year. They are mainly used as aromas and preservatives in food and cosmetics industries. The content and yield of the obtained extracts change across the seasons of the year. The knowledge of these differences is important for essential oils industry to gain the best quality and quantity of products. In this study Thuja occidentalis L. (Eng. northern white cedar) extract was obtained from leaves by maceration in dichloromethane. Plant material was collected during each season of the year and the finished products were thoroughly examined through GC-MS analysis. The seasonal variations of volatile compound composition showed that the most adequate period to obtain T. occidentalis extract on an industrial scale is spring. This is due to the best efficiency (almost 10%) and the highest content of monoterpenes (67%).
Źródło:
Acta Biologica Cracoviensia. Series Botanica; 2022, 64, 1; 7-14
0001-5296
Pojawia się w:
Acta Biologica Cracoviensia. Series Botanica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trójstanowy model Markowa prognozowania wydajności turbiny wiatrowej
Three state Markov model of wind turbine efficiency prediction
Autorzy:
Mazur, D.
Gołębiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/156112.pdf
Data publikacji:
2013
Wydawca:
Stowarzyszenie Inżynierów i Techników Mechaników Polskich
Tematy:
turbina wiatrowa
modele Markowa
prognozowanie
wind turbine
Markov model
prediction
Opis:
W artykule przedstawiona została metoda prognozowania wydajności pracy turbiny oparta na niejawnych łańcuchach Markowa. Niejawne łańcuchy Markowa znajdują zastosowanie w rozpoznawaniu mowy, ale mogą być także wykorzystane do prognozowania przyszłych wartości szeregu czasowego. Zaproponowane w pracy podejście oparte jest na dwóch znanych twierdzeniach związany z algorytmem przód-tył oraz algorytmem Bauma-Welcha. Przy pomocy modelu trójstanowego możliwe jest opisanie bardziej złożonych właściwości ciągu stanów, w którym pracuje turbina wiatrowa zależna od wiejącego wiatru.
This paper presents the wind turbine efficiency prediction model based on implicit Markov chains. As the share of wind generated energy in total energy production constantly increases, the precise prediction of the wind turbine efficiency has become an important issue. Markov chains are used in speech recognition, but can also be used for the future values of the time series prediction. The quality of three state model is investigated, also the methodology of creating such a model is presented. The proposed approach is based on two, well known, algorithms. The forward-backward and Baum-Welch algorithms are used. The use of the three state model allows description of more complex properties of the state sequence in which the wind turbine operates depending on the wind conditions. The investigated method is an alternative to a commonly used method based on the wind velocity and direction measurements and the Weibull distribution of wind speed. Since these measurements are taken at the altitude of 10m this method is inaccurate.
Źródło:
Pomiary Automatyka Kontrola; 2013, R. 59, nr 10, 10; 1073-1075
0032-4140
Pojawia się w:
Pomiary Automatyka Kontrola
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computationally efficient method for determining the most important electrical parameters of axial field permanent magnet machine
Autorzy:
Smoleń, A.
Gołębiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/202137.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
axial flux permanent magnet
2D FEA
numerical optimization
magnes stały
optymalizacja numeryczna
Opis:
This paper describes a numerically efficient method for determining the electrical parameters of axial field permanent magnet machine (AFPM). The presented method aims to accurately determine the back EMF waveform and self-inductance coefficients, while maintaining possibly low computational complexity, which is crucial in case of incorporation of the method in numerical optimization procedure of AFPM construction. The described algorithm is based on 2D FEM with several simplifications. The obtained results have been compared with full 3D FEA conducted with Ansys/Maxwell software, and confirmed by measurements. The result shows that presented method ensures satisfactory accuracy as well as computational time performance.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2018, 66, 6; 947-959
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of the stator inductances of the expanded Park model and an approach on parameter identification using the evolution strategy
Autorzy:
Schmuelling, Ch.
Kreischer, Ch.
Gołebiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/141147.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
evolution strategy
FEM
Park equations
Park theory
synchronous machines
transients
Opis:
Commonly, the Park model is used to calculate transients or steady-state operations of synchronous machines. The expanded Park theory derives the Park equations from the phase-domain model of the synchronous machine by the use of transformations. Thereby, several hypothesis are made, which are under investigation in this article in respect to the main inductances of two different types of synchronous machines. It is shown, that the derivation of the Park equations from the phase-domain model does not lead to constant inductances, as it is usually assumed for these equations. Nevertheless the Park model is the most common analytic model of synchronous machines. Therefore, in the second part of this article a method using the evolution strategy is shown to obtain the parameters of the Park model.
Źródło:
Archives of Electrical Engineering; 2016, 65, 3; 585-599
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Elektroniczna filtracja prądu wyprostowanego
Electronic filtration of the direct current
Autorzy:
Gołębiowski, L.
Gołębiowski, M.
Mazur, D.
Powiązania:
https://bibliotekanauki.pl/articles/1372568.pdf
Data publikacji:
2011
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Napędów i Maszyn Elektrycznych Komel
Tematy:
prąd stały
filtracja elektroniczna
prostownik
Opis:
The circuit, which allows to reduce the current ripples rectified by the 6-pulse rectifier, was presented in this article. Usually for this purpose we can use the choke, but it makes some difficulties and increases costs. In this paper we present the alternative way of the current smoothing, which uses the capacitor, with controlling electronic circuit, instead of choke to smooth the current. The presented simulations shows, that the method of the controlling of the switching on that capacitor in the direct current circuit provides effective method to reduce the higher harmonics of the rectified current. The size of the device which uses electronic filtration of the direct current, presented in this paper, is also smaller than the device with chokes.
Źródło:
Maszyny Elektryczne: zeszyty problemowe; 2011, 3, 91; 147-151
0239-3646
2084-5618
Pojawia się w:
Maszyny Elektryczne: zeszyty problemowe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Prostownik 24-pulsowy z dławikami niesprzężonymi
24-pulse rectifier with non-coupled chokes
Autorzy:
Gołębiowski, L.
Gołębiowski, M.
Mazur, D.
Powiązania:
https://bibliotekanauki.pl/articles/1372626.pdf
Data publikacji:
2011
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Napędów i Maszyn Elektrycznych Komel
Tematy:
prostownik
dławik niesprzężony
Opis:
Operating principle of the 24-pulse rectifier circuit with non-coupled chokes was presented in this article. Thanks to the work of this circuit we can obtain small higher harmonics currents content of the rectified current. Transistors T1, T2, T3, T4 were used to regulate the value of rectified current. Fulfillment of their control by using the PWM method regulates the rectified current. In addition this paper provides the ability of such controlling of transistors work, that the mains current of the circuit contains the smallest possible higher harmonics content, expressed by small value of the THD coefficient.
Źródło:
Maszyny Elektryczne: zeszyty problemowe; 2011, 3, 91; 153-161
0239-3646
2084-5618
Pojawia się w:
Maszyny Elektryczne: zeszyty problemowe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of different methods for excitation of synchronous machines
Autorzy:
Schmuelling, S.
Kreischer, Ch.
Gołȩbiowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1367718.pdf
Data publikacji:
2015
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Napędów i Maszyn Elektrycznych Komel
Tematy:
AC machines
Brushless machines
Electromagnetic transients
Excitation system
Power system simulation
Opis:
The energy turnaround in Germany leads to new operating conditions for small and medium synchronous generators. Since the electricity generation through renewable energy sources, such as wind or photovoltaic, is highly volatile, generators have to run up from standstill into rated operation within several minutes. Hence, it is necessary to compensate a lack of electricity generation caused by wrong weather forecasts. Usually, gas turbine systems provide this possibility. The generator is used as a starter engine due to the connection to a frequency inverter. The excitation current is often provided by static excitation systems. Thus, it is possible to start from standstill and run up the drive until the gas turbine is able to generate a positive torque. A new excitation concept, based on an induction machine with a 3-phase rotor winding, is able to provide an excitation current at 0 rpm and eliminates the need for brushes. To verify the applicability for power systems, both systems are compared under different aspects. The control of the excitation current at different speeds and the possibility to settle shaft oscillations after electrical faults are aspects researched in the paper at hand. A power system simulation is performed with a synchronous machine connected to a grid. Both excitation systems are modeled by equivalent circuit diagrams in Matlab Simscape.
Źródło:
Maszyny Elektryczne: zeszyty problemowe; 2015, 3, 107; 89-93
0239-3646
2084-5618
Pojawia się w:
Maszyny Elektryczne: zeszyty problemowe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Strumień osiowy w modelu 3D MES maszyny indukcyjnej
The axial flux in the 3D FEM model of the induction machine
Autorzy:
Gołębiowski, L.
Gołębiowski, M.
Noga, M.
Skwarczyński, J.
Powiązania:
https://bibliotekanauki.pl/articles/320324.pdf
Data publikacji:
2006
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
strumień osiowy
model 3D MES
elementy krawędziowe
stany dynamiczne maszyny
axial flux
3D FEM model
edge elements
transient states
Opis:
Artykuł poświęcony jest wyjaśnieniu zagadnienia powstawania strumienia magnetycznego osiowego w maszynie elektrycznej na przykładzie maszyny indukcyjnej. Przedstawiono podstawy teoretyczne oraz warunki konieczne powstawania strumienia osiowego. W celu ich potwierdzenia obliczeniami, stworzono model 3D maszyny. Wykorzystuje on elementy skończone węzłowe do aproksymacji potencjału skalarnego oraz krawędziowe do aproksymacji potencjału magnetycznego wektorowego. Uwzględnia skos prętów wirnika oraz prądy skrośne w blachach wirnika. Strumień osiowy jest obliczany przez całkowanie potencjału wektorowego wokół wału maszyny. Trójfazowe uzwojenia stojana zasilane są czteroprzewodowo. Przeprowadzono obliczenia stanów po załączeniu maszyny przy różnych prędkościach obrotowych. Symulowano pęknięcia pierścienia oraz pręta. Wyniki symulacji potwierdziły wyprowadzenia teoretyczne.
The aim of this paper is to provide the explanation of the phenomenon of axial magnetic flux formation in the electric machine on the example of the induction machine. The theoretical bases and necessary conditions of the axial flux formation were presented. In order to verify theoretical considerations the 3D finite elements model of the induction machine was created. This model utilizes both nodal-based and edge-based formulation respectively for scalar and vector potential approximation. The rotor bar skew and cross currents were taken into consideration. The axial flux was calculated by the integration of the vector potential round the machine shaft. The three phase stator windings were supplied with the four-wire line. The calculations/simulations of the transient states of the machine at different rotational speeds were performed. The rotor bar and end ring faults were simulated. The theoretical considerations were confirmed by the results of simulations.
Źródło:
Elektrotechnika i Elektronika; 2006, 25, 2; 147-152
1640-7202
Pojawia się w:
Elektrotechnika i Elektronika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Autotransformator w zasilaniu wielopulsowych układów prostownikowych – metody obliczania jego indukcyjności przy zasilaniu napięciowym
Autotransformer feeding multi pulse rectifier circuits - methods of its inductance calculation at voltage feed
Autorzy:
Noga, M.
Gołębiowski, L.
Gołębiowski, M.
Mazur, D.
Powiązania:
https://bibliotekanauki.pl/articles/1373213.pdf
Data publikacji:
2010
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Napędów i Maszyn Elektrycznych Komel
Tematy:
autotransformator
prostownik
indukcyjność rozproszenia
zasilanie napięciowe
Opis:
3D finite element method was used in this article to calculate inductance matrix of the autotransformer, divided into eigenvectors [W] and eigenvalues [D]. The autotransformer windings were powered by monoharmonic voltages. This method, as an equivalent of the short circuit tests, is more suitable for calculating small values of leakage inductance. The equivalent are here the methods which are using feeding the autotransformer windings by fixed currents (it is equivalent of the idle running tests). The relationship between autotransformer inductance matrix and ripple was obtained. It appeared, that eigenvectors matrix of the inductance matrix of the autotransformer is almost independent from the ripple, and its elements are real numbers. It was treated as transformation matrix: flux linkages - windings currents flows. Relation from the ripple of the eigenvalues of inductance matrix was synthesized by means of ladder circuits. As a result the exact substitute diagram of the autotransformer was obtained. This article is the third one out of four articles presented at this Seminar.
Źródło:
Maszyny Elektryczne: zeszyty problemowe; 2010, 86; 285-290
0239-3646
2084-5618
Pojawia się w:
Maszyny Elektryczne: zeszyty problemowe
Dostawca treści:
Biblioteka Nauki
Artykuł
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