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EN
The article presents issues concerning the certification of quality management system in an enterprise according to the requirements of the International Standard ISO 9001:2000 (PN-EN ISO 9001). The list of presented matters covers: -the basis of certification, -the overall requirements of the ISO 9001, -the reasons for certification of quality management system and the circumstances of choosing a certifying institution, -the course of the certification process, -the benefits of certification.
EN
The article discusses the issue of auditing quality systems in an organization with respect to the ISO 19011:2002 (PN-EN ISO 19011:2003) regulation. The covered topics include the definition of a quality audit, the principles of auditing, professional characteristics and competences of an auditor and the conduct of a quality audit.
EN
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.
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EN
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.
EN
The article presents knowledge as a distinctive element of the process of asset transformation in an industrial company. It has been shown, that in the XXI century knowledge has become a strategic asset of an enterprise and the ability of every organization to learn quickly is a crucial element of gaining competitive advantage.
PL
Przedstawiono zasady współpracy układu turbina wiatrowa-generator wielofazowy inset SMPMSM (Surface Mount Permanent Magnet Synchronous Motor) z siecią energetyczną. Dzięki zastosowaniu iniekcji prądów trzeciej harmonicznej lepiej wykorzystano możliwości generatora. Potwierdzono w ten sposób zasadność stosowania generatorów wielofazowych.
EN
This paper deals witch the cooperation of the wind turbine - multiphase inset SMPMSM generator system with the power grid. The fundamental and 3rd harmonic current cooperation is used to increase the generator performance. This is accomplished by means of the 3rd harmonic current injection. The validity of the application of multi-phase generators is confirmed.
PL
W zakładach produkujących spawane konstrukcje metalowe maszyny do cięcia termicznego są podstawowymi maszynami obróbczymi. Są to maszyny stosunkowo drogie, ich właściwy wybór dla potrzeb zakładu jest sprawą o tyle istotną, że może on wpłynąć na zdolności produkcyjne zarówno asortymentowe, jak i ilościowe.
EN
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.
EN
In the article was presented a definition, functions, market factors and elements of creation quality policy in an enterprise. Some practical examples of quality policy in industry companies in the Szczecin voivodship is included.
PL
Przedmiotem badań był 18-to pulsowy przekształtnik z autotransformatorem różnicowo-widełkowym o pięciu uzwojeniach na każdej kolumnie i mocy wyjściowej 50kW. Obliczenia macierzy indukcyjności rozproszenia uzwojeń wykonano dla 120 (5!) możliwych kombinacji ich ułożenia w oknie autotransformatora z wykorzystaniem programu Ansys. Z przebiegów dynamicznych, obliczonych z uwzględnieniem zjawiska nasycenia obwodu magnetycznego, zjawiska histerezy magnetycznej oraz strat wiroprądowych, uzyskano wartości THD prądów sieci przekształtnika z zakresu 4-8%.
EN
This article reports the results of a study of 18-Pulse AC/DC converter with differential fork autotransformator with 5 windings on each column and 50kW of effective power. The authors use Ansys application to perform the calculations of a leakage inductance matrix for 120 (5!) possible combinations of windings placement in autotransformer window. Next, THD values of corwerter phase currents of 4-8% range were obtained from dynamic transient calculations with the consideration of magnetic saturation, magnetic hysteresis and eddy current losses.
EN
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.
EN
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.
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EN
This paper deals witch the cooperation of the wind turbine - multiphase inset SPMSM generator system with the power grid. The fundamental and 3rd harmonic current cooperation is used to increase the generator performance. This is accomplished by means of the 3rd harmonic current injection. The validity of the application of multi-phase generators is confirmed.
PL
Niniejszy artykuł dotyczy współpracy turbiny wiatrowej - wielofazowego generatora SPMSM z siecią energetyczną. Współpraca podstawowej i trzeciej harmonicznych prądu służy poprawie wydajności generatora. Jest to osiągane za pomocą iniekcji 3 harmonicznej prądów stojana. W ten sposób potwierdza się zasadność stosowania generatorów wielofazowych.
EN
This article presents the range and the essential features of the costs of quality, the role that the balance sheet of the costs of quality plays in companies, and the assessment of the implementation and advancement of the costs of quality analysis in Fabryka Mechanizmów Samochodowych POLMO SA in Szczecin.
PL
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.
EN
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.
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Content available remote Monitoring of End Winding Vibrations using Neural Networks
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EN
In this paper the applicability of a radial basis neural network for monitoring of generator end winding vibrations is investigated. The modelling of the vibrational behaviour is needed to detect changes in the mechanical structure of the machine at an early stage. A case study and a significance analysis on operating parameters are presented. Furthermore the thermal equalization process after due to changes in operation is discussed.
PL
W pracy zbadano możliwość zastosowania sieci neuronowej w monitoringu drgań połączeń czołowych uzwojeń generatora. Wczesne wykrycie zmian w strukturze mechanicznej maszyny jest możliwe dzięki modelowaniu drgań połączeń czołowych uzwojeń podczas pracy generatora. W pracy przedstawiono studium przypadku oraz analizę istotności parametrów pracy generatora. Przedyskutowano również wpływ procesów termicznych, zachodzących w generatorze pod wpływem zmiany parametrów pracy, na jakość modelowania siecią neuronową.
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PL
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.
EN
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.
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PL
W pracy przedstawiono trzy sposoby wyznaczania indukcyjności rozproszeń uzwojeń autotransformatora metodą elementów skończonych. Do obliczeń wykorzystano model autotransformatora 3D oraz dwa modele 2D. W pracy wyodrębniono różnice występujące pomiędzy macierzami indukcyjności rozproszeń uzyskanymi opisywanymi metodami, oraz przeanalizowano ich wpływ na obliczenia symulacyjne wielopulsowych przekształtników energoelektronicznych.
EN
This article presents three procedures of calculating an autotransformer's leakage inductance matrix with the use of the finite element method. The calculations were performed in ANSYS application. The differences between the autotransformer's leakage inductance matrices obtained with the described methods were isolated, also the analysis of their influence on multi-pulse electronic power converter calculations were made.
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