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Modeling the impact of rotor movement on non-linearity of motor currents waveforms in high-speed PMSM drives
PublikacjaMotor current measurement techniques as well as predictive control algorithms for electric drives rely on an assumption of linear motor currents changes resulting from constant inverter output voltages. Recent research has reported that this assumption does not hold in motors with short electrical time constant, and in drives whose rotor position advances substantially during a control period. This paper proposes a simulation model...
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Dielectric Barrier Discharge Systems with HV Generators and Discharge Chambers for Surface Treatment and Decontamination of Organic Products
PublikacjaThe article presents applications of systems with power electronic converters, high voltage transformers, and discharge chambers used for nonthermal, dielectric barrier discharge plasma treatment of a plastic surface and decontamination of organic loose products. In these installations, the inductance of the high voltage transformers and the capacitances of the electrode sets form resonant circuits that are excited by inverters....
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Count Data Modeling About Relationship Between Dubai Housing Sales Transactions and Financial Indicators
PublikacjaIn this study, illustrating and comparing the performances of count data models such as Poisson, negative binomial (NB), Hurdle and zero-inflated models for the determination of factors affected housing sales in Dubai. Model comparisons are made via Akaike’s information criterion (AIC), the Vuong test and examining the residuals. Main purpose of this study is building reliable statistical model for relationship between Dubai housing...
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Oversizing the photovoltaic generator capacity in a micro photovoltaic plant
PublikacjaA significant part of photovoltaic micro installations in Poland is characterized by photovoltaic generator oversizing in relation to the inverter. The idea of oversizing, however, still raises doubts among some plant owners. In the paper, the energy yield of installation with an oversized and not oversized photovoltaic generator is presented on selected examples, showing the legitimacy of oversizing.
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The multiscalar control of induction motor with the sliding mode controllers
PublikacjaThe control structure of induction motor is proposed in this paper. The structure of multiscalar control with conventional PI - controllers is well known in literature. The sliding mode multiscalar control (SMMC) conception is presented in this paper. The induction motor is fed by voltage source inverter. Comparison between two multiscalar control method is showed.
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Appendix E
PublikacjaThe advance of variable speed drives systems (VSDs) engineering highlights the need of specific technical guidance provision by electrical machines and drives manufacturers, so that such applications can be properly designed to present advantages in terms of both energy efficiency and expenditure. This book presents problems and solutions related to inverter-fed electrical motors. Practically orientated, the book describes the...
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Exchange-Traded Funds in Europe
PublikacjaExchange-Traded Funds in Europe provides a single point of reference on a diverse set of regional ETF markets, illuminating the roles ETFs can play in risk mitigation and speculation. Combining empirical data with models and case studies, the authors use diffusion models and panel/country-specific regressions—as well as graphical and descriptive analyses— to show how ETFs are more than conventional, passive investments. With new...
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The conditions of the business services sector in Poland and its competitiveness in the global market
PublikacjaThe following article presents the conditions of the business services sector (BSS) in Poland and the assessment of its competitiveness in the global market. The first section discusses the BSS sector and the categories of the provided services, in the division of business process outsourcing, shared services center, information technology outsourcing, research and development. Next the authors presents the status of the business...
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Wisłoujście Fortress. Architectural investigation and analysis (2013)
PublikacjaIn 2013, as part of archaeological and architectural reserch conducted in the Area of Wisłoujście Fortress, an inventory and architectural studies of the rooms of tenement houses in the Ring, serving as kitchen, were performed. Work consisting in preparing measurement documentation, drawings and descriptive documentation was the first such study conducted inside buildings at Fort Carre. The article presents preliminary results...
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Wykorzystanie narzędzi CAD do wyznaczania właściwosci bezwładnościowych i sztywnościowych stanowiska badawczego
PublikacjaPrzedstawiono przykład wykorzystania narzędzi CAD 3D (Inventor) do wyznaczania bezwładności (mas i momentów bezwładności) oraz sztywnosci głównych elementów będących pod wpływem wymuszeń dynamicznych generowanych przez tarcie w badanym styku ślizgowym. Wykorzystując system ANSYS przeprowadzono obliczenia charakterystyk drgań własnych na utworzonych bryłowych modelach elementów.
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Zarządzanie łańcuchem logistycznym w procesie produkcyjnym cegieł silikatowych w przedsiębiorstwie Prefabet.
PublikacjaCelem niniejszego artykułu jest przedstawienie systemu zarządzania łańcuchem logistycznym w procesie produkcji cegieł silikatowych w przedsiębiorstwie Prefabet. Ważnym aspektem należytego funkcjonowania i zarządzania łańcuchem logistycznym jest wykorzystanie metody VMI – Vendor Management Inventory. Wskazana metoda zakłada, iż producent/dostawca sam generuje zamówienia na rzecz klienta na podstawie otrzymanych...
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Formowanie napięć wyjściowych trójfazowego przekształtnika sieciowego
PublikacjaW artykule przedstawiono kompensację dwu zasadniczych zjawisk powodujących zniekształcenia prądów fazowych przekształtnika sieciowego. Pierwszym z nich są zniekształcenia napięcia sieci. W celu ich eliminacji zaproponowano uśrednianie za okres podstawowej harmonicznej uchybu regulatora napięcia obwodu pośredniczącego oraz predykcję napięcia sieci. Drugim natomiast są zniekształcenia napięć wyjściowych przekształtnika sieciowego....
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Electric shock hazard in circuits with variable-speed drives
PublikacjaThe conventional approach to electrical safety under fault condition in typical power systems considers earth fault currents of sinusoidal waveform and frequency of 50/60 Hz. However, in circuits with variable-speed drives, there is earth fault current flow with harmonics, and these harmonics influence the threshold of ventricular fibrillation. The paper presents earth fault current waveforms in circuits with variable-speed drives...
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Balkan Stock Exchanges – Consideration of the Length of the Estimation Window in Similar Markets
PublikacjaPurpose: We study if capital markets in the Balkan are closely and positively related in terms of rate of return, risk, efficiency, and maximum cumulative loss in relation to different lengths of the estimation window. Design/Methodology/Approach: The research was carried out for the period from 01/01/2017 to 31/12/2019 using portfolio analysis. It was divided into an estimation window (01/01/2019 to 31/12/2019) and another with...
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Rekuperace elektrické energie v MHD
PublikacjaAsynchronní pohony, motory BLDC, trakční invertory, IGBT tranzistory, rekuperace energie – to jsou hesla, se kterými se můžeme často potkat, když si pročteme propagační materiály výrobců moderních tramvají a trolejbusů. Často se nám tyto prvky jeví jako indikátory hypermoderních technologií, ale ve skutečnosti se stává, že pod některými názvy se skrývá řešení známé inženýrům už dlouhá desetiletí. Tak je tomu také s rekuperací elektrické...
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Stock Markets’ Reactions to the Announcement of the Hosts. An Event Study in the Analysis of Large Sporting Events in the Years 1976–2032
PublikacjaThis study attempts to estimate the impact of the announcements of hosts of large sporting events on domestic stock markets. The research problem is to establish a connection between the uniqueness of a sporting event and investors’ beliefs through stock price behavior. Using appropriate estimation windows, 13 different sporting events classified as large, including mega and major events, were tested. The obtained results show...
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Pompownie dużej mocy z falownikiem wędrującym średniego napięcia
PublikacjaArtykuł zawiera rys rozwoju napędów przekształtnikowych w stacjach pomp, w szczególności regulacji wydatku kilku pomp, po kolei, przez jeden przemiennik częstotliwości. Omówiono podstawy teoretyczne zjawiska pola niestłumionego i napięcia resztkowego silników, które utrudniają szybkie przełączania silnika pompy pomiędzy zasilaniem regulowanym przez falownik a zasilaniem z sieci. Przedstawiono zasady transferu (przełączania) synchronicznego...
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Closed-Loop Control System Design for Wireless Charging of Low-Voltage EV Batteries with Time-Delay Constraints
PublikacjaThis paper presents an inductive power transfer system on the basis of a double single- phase three-level T-type inverter and two split transmitting coils for constant current and constant voltage wireless charging of low-voltage light electric vehicle batteries with closed-loop control, considering time-delay communication constraints. An optimal control structure and a modified control strategy were chosen and implemented to...
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Simulation model of IPMSM drive with rotor position estimator
PublikacjaThe paper presents a simulation model of electric drive consisting of: IPMSM motor, inverter and digital controller. The model was designed in Mathlab/Simulink. By modelling of the controller its discrete operation was taken into account in order to simulate precisely a specific sensorless control algorithm. A method for estimation of angular rotor position was proposed. Its mathematical algorithm was explained and errors were...
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Evolution of the HVDC Link Connecting Offshore Wind Farms to Onshore Power Systems
PublikacjaThis paper presents an overview of the DC link development and evolution dedicated to HVDC structure for connecting offshore wind power plants to onshore power systems. The growing demand for the green energy has forced investors in power industry to look for resources further out at sea. Hence, the development of power electronics and industrial engineering has enabled offshore wind farms to be situated further from the shore...
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Implementation of International Standards of Fiscal and Monetary Transparency - Case of Poland
PublikacjaResearch background: Financial managers, investors, lenders, counterparties and citizens should have useful, reliable, timely, complete, comparable, readable information on fiscal and monetary policy. The actions taken and instruments used by fiscal and monetary authorities have an important impact on economic conditions. Purpose of the article: The aim of the article is to assess Poland's compliance with international standards...
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Inwentaryzacja miejsc zdarzeń kryminalnych przy wykorzystaniu naziemnego skaningu laserowego
PublikacjaInwentaryzacja miejsc zdarzeń kryminalnych przy wykorzystaniu naziemnego skaningu laserowego jest rozwiązaniem często spotykanym przy w rozwiniętych krajach Europy i Ameryki Północnej. W Polsce znajdujemy pierwsze zastosowania do rejestrowania zdarzeń kryminalnych o szczególnym stopni skomplikowania lub związanych z nieprzeciętną liczbą ofiar. Zasadniczo jednak skaning laserowy stosuje się w sprawach o zabójstwo, a rzadko w rozwiązaniach...
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CROWDFUNDING OF RESEARCH PROJECTS IN POLAND
PublikacjaCrowdfunding recently became a very popular way of funding, which allows funding almost everything, from minor personal projects to expensive commercial ones, as long as we can find investors. It may also be a new opportunity for entrepreneurial researchers, who may attract capital investment in companies that are promised to own developed technologies. Social financing of science is well suited to reduce some of the biggest problems...
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Electrical conductivity and relaxation processes in V2O5 nanorods prepared by sol–gel method
PublikacjaProperties of high purity V2O5 nanorods prepared by a sol – gel method are presented. The studied materials were characterized by: X-ray diffractometry (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The electrical impedance was measured as a function of temperature and frequency. The obtained results show that the electrical conductivity increases with increasing temperature. The d.c. conductivity...
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Projektowanie tras tramwajowych przy wykorzystaniu Mobilnych Pomiarów Satelitarnych
PublikacjaW pracy przedstawiono metodykę projektowania tras tramwajowych dostosowaną do rozwijanej w Zespole Naukowym metody Mobilnych Pomiarów Satelitarnych. Opisano badania inwentaryzacyjne wykonane na torach tramwajowych, których wyniki posłużyły jako dane wejściowe w procesie projektowania. Pokazano, w jaki sposób dostosowano analityczne algorytmy projektowania tras kolejowych do specyfiki układów geometrycz-nych występujących w torach...
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Compensation of Dead Time Effects for Shunt Active Power Filters
PublikacjaThe paper presents a comprehensive approach to the compensation of the grid current distortion for shunt active power filter systems. Four different sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, time delays in the estimation of compensating currents and grid voltages, fluctuations of the dc bus voltage, and the distortion of inverter output voltages due...
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Conducted emi identification in power electronic converters : modeling of EMI generation and propagation using circuit simulation and wiener filtering methods.
PublikacjaThis work presents the circuit simulations and the conventional signal processing technique (Wiener filtering) in order to reconstruct conducted ElectroMagnetic Interferences (EMI), generated and propagated in power electronics converters. In the simulation study, the most accurate presently available models of components of circuit have been used and improved. The proposed Wiener filtering method allows to identifying the transfer...
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MARKETING STRATEGY - SPACE AS A PRODUCT.ARCHITECTURE AS A MARKETING DEVICE.
PublikacjaSpace has its measurable financial value. From the economic point of view place can be treated as a product that fights for appearing in tourists' and investors' consciousnesses. Space - treated as the object of demand and supply - becomes an element in a marketing game. To reach its maximal value the given space should be competitive to other spaces, from which it wants to stand out. However, in the field of architecture - and...
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Technologies for deodorization of malodorous gases
PublikacjaThere is an increasing number of citizens’complaints about odor nuisance due to production or service activity. High socialawareness imposes pressure on entrepreneurs and service providers forcing them to undertake effective steps aimed at minimi-zation of the effects of their activity, also with respect to emission of malodorous substances. The article presents informationabout various technologies used for gas deodorization....
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Dynamic Bankruptcy Prediction Models for European Enterprises
PublikacjaThis manuscript is devoted to the issue of forecasting corporate bankruptcy. Determining a firm’s bankruptcy risk is one of the most interesting topics for investors and decision-makers. The aim of the paper is to develop and to evaluate dynamic bankruptcy prediction models for European enterprises. To conduct this objective, four forecasting models are developed with the use of four different methods—fuzzy sets, recurrent and...
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Underdiagnosis of Major Depressive Episodes in Hemodialysis Patients: The Need for Screening and Patient Education.
PublikacjaThis article aims to identify the reasons why patients with major depressive episode (MDE) do not seek treatment for their mental disorder. 89 out of 208 persons screened were diagnosed with major depressive episode using the Mini-International Neuropsychiatric Interview. 85 individuals with untreated depression filled out the following questionnaires: Beck Depression Inventory, List of Explanations of Well-Being (LEWB), Brief...
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Comprehensive compensation of grid current distortion by shunt active power filters
PublikacjaThe paper presents a comprehensive approach to the compensation of grid current distortion in shunt active power filter systems. Four sources of current distortion are addressed: imperfect grid synchronization caused by the distortion in the grid voltages, time delays in the evaluation of grid voltages and computation of compensating currents, fluctuations of the dc bus voltage, and the distortion of inverter output voltages due...
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IMPACT OF CAUSTICS ON ACOUSTICS OF WHISPERING GROTTOES IN THE OLIWA PARK IN GDAŃSK
PublikacjaIn the paper, caustics are discussed as ordered forms of focus broadening occurring in concave mirrors. An example of caustics created by the reflection of the light from the concave mirror is shown. Against this background, the possibility to observe caustics in rooms is pointed out. Special emphasis is put on large rooms of historic character, as such interiors frequently include acoustic mirrors in the form of arched vaults...
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Burnout as a State: Random-Intercept Cross-Lagged Relationship Between Exhaustion and Disengagement in a 10-Day Study [Response to Letter]
PublikacjaWe are writing in response to the Letter to the Editor by Block, Bair, and Carillo regarding our study, which took a multilevel approach to examine cross-lagged and co-existing relationships between exhaustion and disengagement, measured daily for ten consecutive working days using the Oldenburg Burnout Inventory (OLBI). We assessed the job burnout symptoms using only eight items, all of them worded negatively. Following Block,...
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Changes in Functional and Spatial Layouts of Polish Single-Family Houses
PublikacjaArticle presents the evolution of functional and spatial layouts of single-family houses in Poland, with particular emphasis on the functions of a contemporary house. Singlefamily housing constitutes a significant part of the construction market in Poland. The way of forming functions in single-family buildings in the historical cycle has characteristic features resulting from the culture of the society in a given period. The functional...
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Urban Mentoring as a new polish management technique in participatory planning
PublikacjaA decade of experience in implementation of numerous urban modernization projects in Poland resulted in a lively debate on socialization of the planning process, in which the matter of the public space quality has become the center of gravity. In those years, transformation from the classic administrative model of „bureaucracy planning” to the model of „management planning” has not been complete. The socialist primacy of the public...
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Zastosowanie modułu symulacji dynamicznej programu CAD w analizie układu napędowego elektronarzędzia
PublikacjaW referacie przedstawiono analizę mechanicznego układu przeniesienia napędu elektronarzędzia (wyrzynarki elektrycznej) przy zastosowaniu Modułu Symulacji Dynamicznej (MSD) programu Autodesk Inventor (AI). Opracowano modele 3D poszczególnych części elektronarzędzia i połączono je przy zachowaniu tzw. kinematyki odwrotnej. Przeprowadzono analizę wpływu poszczególnych węzłów kinetycznych na przebieg momentu na wale silnika elektrycznego....
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Direct chromatographic methods in the context of green analytical chemistry
PublikacjaWe review analytical protocols based on gas and liquid chromatography (GC and LC), but involving no sample preparation.Green analytical chemistry seeks to minimize negative impacts of analytical chemistry. Direct analytical methods ideally fulfillthis requirement, as they preclude sample preparation - the most polluting step of the analytical procedure.We describe examples of GC methodologies for environmental and food analysis...
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Ocena zastosowania wybranych reguł wymiany narzędzi w systemie produkcyjnym
PublikacjaIn this paper, an integrated analytical and simulation modelling framework has been developed with the objective to explore total system planning and operational issues. It enables in particular structuring the alternative process flow in manufacturing systems and their extended investigation under different tool exchange rules with limited number of tool inventory. Simulation studies performed with the proposed rules in the environment...
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Acoustics-related aspects of historic interior modernization projects
PublikacjaThe paper presents three historic interiors in which modernization projects have been carried out having an important impact on their acoustic qualities. Two of the described case studies are positive examples of solving the problem of a natural contradictions between modern technical standards and strict discipline imposed by the heritage conservation system. On the other hand, the effect of neglecting the acoustic needs when...
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High Rise Building: The Mega Sculpture Made Of Steel, Concrete and Glass
PublikacjaHigh rise building has transformed from providing not only the expansion of floor space but functioning as mega sculpture in the city. The shift away from economic efficiency driven need is only expected to grow in the future. Based on literature studies; after analysing planning documents and case studies, it was examined whether the presumption that gaining the maximum amount of usable area is the only driving factor; or if the...
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Frequency-dependent coupling model for microwave band-pass filter
PublikacjaThe goal of this work was to create a circuit model which represents frequency-dependent coupling between microwave resonators. Our models are designed for in-line filters. The frequency-dependent coupling enables one to realize a transmission zero which is not possible in classical approach with frequency independent inverters. In addition, the proposed model allows us to observe out-of-band behavior, e.g. spurious resonance....
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Offshoring and outsourcing in Visegrad countries, Advantages and disadvantages.
PublikacjaOutsourcing and offshoring are getting more and more popular in the “new EU” coun-tries. They constitute very attractive venues for more developed EU countries to outsource or offshore their business activities. Authors of the article have investigated the advantages and disadvantages of locating outsourcing activities in each of the Visegrad (V4) countries. The authors have studied macroeconomic factors based on the reports of...
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Inwentarz księgozbioru Wiktorii z Scheillów Wendorffowej jako przykład spisu biblioteczki ziemiańskiej z pierwszej połowy XIX wieku
PublikacjaPrzedmiotem pracy jest rękopiśmienny inwentarz księgozbioru Wiktorii z Scheillów Wendorffowej, wykonany na podstawie zapisu testamentowego. Stanowi on przykład spisu XIX-wiecznej biblioteczki ziemiańskiej, który znajduje się w aktach notarialnych. Dokonano rekonstrukcji spisu 222 książek oraz poddano go krótkiej analizie. Zapisy z rękopisu uzupełniono opisami bibliograficznymi poszczególnych odnalezionych pozycji; składają się...
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Estimation of interior-permanent-magnet-synchronous-motor rotor position by analysis of phase-current derivatives
PublikacjaThis paper describes an algorithm for estimation of IPMSM rotor angular position. The algorithm uses derivatives of motor phase currents resulting from PWM modulation to obtain the rotor position. The presented method is designed for medium- and high-speed range, since it is based on determination of the EMF vector. Calculation of the motor position is performed in every PWM cycle. The standard SV-PWM method is used to determine...
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Sensorless algorithm for sustaining controllability of IPMSM drive in electric vehicle after resolver fault
PublikacjaThis paper presents a sensorless algorithm designated for the emergency control of an interior permanent magnet synchronous motor (IPMSM) drive in electric or hybrid vehicle. The algorithm is based on analysing the derivatives of motor phase currents measured over the duration of particular inverter states. The method is computationally simple and does not require additional hardware since the derivatives are measured indirectly....
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Possibility of Fault Detection in Sensorless Electric Drives
PublikacjaThe work presents a fault detection method for an induction motor drive system with inverter output filter. This approach make use of a load torque state observer, which complete structure is presented along with the used control structure. Moreover, the demonstrated drive system operates without rotor speed measurement in conjunction with the multiscalar control. The verification of the demonstrated idea was performed on an experimental...
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Development and performance analysis of a novel multiphase doubly-fed induction generator
PublikacjaThis paper presents the research into the design and performance analysis of a novel five-phase doubly-fed induction generator (DFIG). The designed DFIG is developed based on standard induction motor components and equipped with a five-phase rotor winding supplied from the five-phase inverter. This approach allows the machine to be both efficient and reliable due to the ability of the five-phase rotor winding to operate during...
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A Review of Reduction Methods of Impact of Common-Mode Voltage on Electric Drives.
PublikacjaIn this survey paper, typical solutions that focus on the reduction in negative effects resulting from the common-mode voltage influence in AC motor drive applications are re-examined. The critical effectiveness evaluation of the considered methods is based on experimental results of tests performed in a laboratory setup with an induction machine fed by an inverter. The capacity of a common-mode voltage level reduction and voltage...
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Electrical mapping of AISI 304 stainless steel subjected to intergranular corrosion performed by means of AFM-LIS in the contact mode
PublikacjaThe paper presents results of the AFM-based approach to local impedance spectroscopy (LIS) measurements performed in a 20 20 lm grid within an austenite grain–grain boundary region for sensitized AISI 304 stainless steel (SS). Maps of electrical parameters obtained on the basis of localized impedance spectra were demonstrated, presenting their changes and correlation with the sample topography. Performed research revealed significant...