Wyniki 1-9 spośród 9 dla zapytania: authorDesc:"Jacek F. Gieras"

Superconducting Electrical Machines - State of the Art

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The paper contains a review of recent advancements in high temperature superconducting (HTS) machines. With the discovery of HTS cuprate-perovskite ceramic materials in 1986, the United States almost immediately resurrected interest in superconducting applications. The U.S. Department of Energy (DoE) and Defense Advanced Research Projects Agency (DARPA) have taken the lead in research and development of HTS electric machines and other HTS electric power applications. Recent developments in HTS electrical machines in Europe and Japan have been summarized too. The paper considers only those developments in HTS machines, which have been completed with working prototypes that passed laboratory tests. Fundamentals of superconductivity, HTS 1st generation (BSCCO) wires, 2nd generation (YBCO[...]

New Applications of Synchronous Generators

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High-speed synchronous generators rated in the power range of megawatts have been discussed. These generators are nowadays necessary for new aerospace missions. Requirements, ferromagnetic materials, magnetic circuit, electromechanical design and cooling techniques for high-speed multimegawatt generators have been discussed. First prototypes (1 MW and 2.5 MW) have been outlined. Streszczenie. Artykuł dotyczy prądnic synchronicznych o wysokiej prędkosci obrotowej oraz mocy rzędu megawatów stosowanych w aparatach latających. Prądnice takie są obecnie konieczne do misji specjalnych w przestrzeni powietrznej. Omówiono wymagania, materiały ferromagnetyczne, obwody magnetyczne, elementy projektowania elektromechanicznego oraz techniki chłodzenia prądnic o wysokiej prędkości oraz mocy rzędu megawatów. Przedstawiono pierwsze prototypy takich prądnic (o mocach 1 MWoraz 2.5 MW). (Nowe zastosowania generatorów synchronicznych) Keywords: synchronous generators, multimegawatt, aerospace, magnetic circuits, cooling systems, design, first prototypes Słowa kluczowe: prądnice synchroniczne, moc rzędu megawatów, przestrzeń powietrzna, obwody magnetyczne, układy chłodzenia, projektowanie, pierwsze prototypy Introduction The speed of a.c. machines increases with increase in the input frequency. The electromagnetic torque is proportional to the electromagnetic power and number of pole pairs and inversely proportional to the frequency. High speed and high frequency armature current reduce the dimensions and mass of electrical machines. At present, the maximum power of high speed (over 5000 rpm) aerospace synchronous generators does not exceed 500 kW. Several airborne power missions are now evolving that will require lightweight multimegawatt electrical power systems, e.g., directed energy weapon (DEW) and airborne radar (AR) [1, 12, 10, 19]. New high power airborne and mobile military systems will require 1 to 6 MW of electrical power generated at speeds[...]

Electric Power System of Tu-154M Passenger Aircraft

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The paper discusses the electric power system of the Tu-154M aircraft. After brief introduction to aircraft power systems, the results of reverse design and analysis of the GT40PCh6 wound-field synchronous generator including short circuit have been presented. Electric power distribution and assignment of electric grids (channels) to respective aircraft energy consumers has been discussed. Most important electric loads, i.e., the fuel system with electric motor driven pumps, wing anti-ice electric system and exterior and interior lighting equipment have been described. An example of failure of GT40PCh6 synchronous generator is the fire of the Tu-154B-2 on January 1, 2011 before taking off at Surgut airport (flight 7K348). Streszczenie. Artykul omawia system elektroenergetyczny samolotu Tu154M. Po krotkim wprowadzeniu do systemow elektroenergetycznych samolotow, przedstawiono wyniki projektowania odwrotnego oraz analizy generatora synchronicznego GT40PCh6 o wzbudzeniu elektromagnetycznym z uzwglednienium przebiegow pradow podczas zwarcia. Opisano dystrybucje energii elektrycznej oraz przyporzadkowanie odbiornikow energii elektrycznej samolotu do poszczegolnych sieci (kanalow). Scharakteryzowano najwazniejsze obciazenia elektryczne, tzn. system paliwowy z pompami napedzanymi silnikami elektrycznymi, system elektryczny zapobiegajacy osadzaniu sie lodu na frontowych powierzchniach skrzydel oraz oswietlenie zewnetrzne i wewnetrzne. Przykladem awarii generatora synchronicznego GT40PCh6 jest pozar Tu-154B-2 w dniu 1 stycznia 2011 przed startem na lotnisku w Surgucie (lot 7K348). (System elektroenergetyczny samolotu pasazerskiego Tu-154M) Keywords: aircraft electric power system, distribution system, electric loads, electric motor-driven fuel pumps, fuel system, lighting, synchronous generator, Tu154M, wing anti-ice electric system Słowa kluczowe: generator synchroniczny, odbiorniki energii, oswietlenie elektryczne, pompy paliwa napedzane silnikami[...]

Electrical Ignition of Fuel-Air Mixture in Aircraft Fuel Tanks

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The fuel system, electric equipment of fuel tank and wiring, fuel flammability, mechanisms of electrical ignition and possibility of explosion of fuel-air mixture as a result of arcing and/or static electricity in fuel tanks of commercial aircraft has been analyzed. Approximate equations for minimum ignition energy (MIE) in fuel tanks have been derived. Examples of explosions of fuel tanks include the air crash of Boeing 747-131 TWA 800 on June 17, 1996 and explosion of Boeing 727-200 at Bangalore Airport on May 4, 2006. Although probability of explosion of fuel in the wing tanks due the electric short circuit, arcing or static electricity is low, this problem should be always carefully considered in examinations of air crashes. Streszczenie. Przedstawiono analize ukladu paliwowego, wyposazenia elektrycznego i przewodow zbiornikow paliwa, zapalnosci paliwa, mechanizmow zaplonu elektrycznego oraz mozliwosci wybuchu mieszanki paliwo-powietrze na skutek luku elektrycznego lub ladunkow statycznych w samolotach pasazerskich. Zostaly wyprowadzone zaleznosci do obliczen przyblizonych minimalnej energii zaplonu w zbiornikach paliwa. Do wybuchow zbiornikow paliwa doszlo podczas lotu Boeinga 747-131 TWA 800 17 czerwca, 1996 oraz podczas postoju Boeinga 727-200 na lotnisku w Bangalore 4 maja 2006. Chociaz prawdopodobienstwo wybuchu oparow paliwa w zbiornikach paliwa na skutek zwarcia instalacji, luku elektrycznego czy tez ladunkow statycznych jest niskie, problem ten powinien byc zawsze dokladnie rozwazony podczas badan wypadkow lotniczych. (Zaplon elektryczny mieszanki paliwo-powietrze w zbiornikach paliwa samolotow) Keywords: aircraft, air-fuel mixture, electrical wiring, electrical equipment, explosion, fuel system, fuel tank S.owa kluczowe: samolot, mieszanka paliwo-powietrze, przewody elektryczne, wyposazenie elektryczne, wybuch, uklad paliwowy, zbiornika paliwa Introduction Civil transport aircraft use the wing structure as an integral fuel tan[...]

The 9th International Symposium on Linear Drives for Industry Applications LDIA2013

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The 9th International Symposium on Linear Drives for Industry Applications LDIA2013 was organized by Zhejiang University, Hangzhou, Zhejiang Province, P.R. China. The Symposium was co-sponsored by the Linear Machines Institute of China, Electrotechnical Society (CES) and the Institute of Electrical Engineering of Chinese Academy of Science, and by the IEEE Industry Applications Society (IEEE IAS). The venue was the Zhejiang Hotel (also called ZTG Zhejiang Hotel) located near the West Lake scenic spot in Hangzhou (Fig. 1). At the west door of Zhejiang Hotel, there is entrance to the secret underground air [...]

PM Generator for Novel Architecture of Wind Turbines DOI:10.12915/pe.2014.10.01

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The paper deals with a permanent magnet (PM) generator for novel architecture of wind turbines. The proposed wind turbine consists of a number of integrated lower-poer individual generators. The individual generators can be arranged in a rectangular matrix, hexagon or in a circle. The paper discusses sizing procedure for this type of generators, electromagnetic calculations including the finite element method (FEM) simulation, performance characteristics and advantages of this type of wind generator. As an example, a PM brushless generator with concentrated non-overlap stator coils has been considered. Streszczenie. Artykuł dotyczy prądnicy bezszczotkowej o magnesach trwałych do nowej architektury turbin wiatrowych. Proponowana turbina wiatrowa składa się z pewnej liczby zintegrowanych jednostek o mniejszej mocy. Poszczególne prądnice mogą być zestawione w matrycę prostokątną, hexagon lub wpisane w okrąg. W artykule omówiono procedurę wymiarowania tego typu prądnic, obliczenia elektromagnetyczne, w tym rownież za pomocą metody elementów skończonych (MES), charakterystyki pracy oraz zalety. Jako przykład, została rozważona prądnica bezszczotkowa o magnesach trwałych z uzwojeniem stojana o cewkach o parametrach skupionych i rozpiętości jednej podziałki żłobkowej. Nowa architektura prądnicy do turbin wiatrowych o magnesach trwałych Keywords: wind turbine, novel architecture, permanent magnet generator, electromagnetic calculations, performance characteristics. Słowa kluczowe: turbiną wiatrowa, nowa architektura, prądnica o magnesach trwałych, obliczenia elektromagnetyczne, parametry. doi:10.12915/pe.2014.10.01 Introduction Wind turbine generators convert wind energy into electrical energy with the aid of mechanical rotation of a bladed rotor hub. In the past, most wind turbines have utilized heavy gearboxes to convert slow, powerful rotor hub rotation into much faster rotation of a driveshaft connected mechanically to the electrical genera[...]

Creativity and innovations in the 21st Century DOI:10.15199/48.2019.02.01

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Introduction Nowadays, new developments in engineering and information technology require design engineers to have qualities of high level of creativity, inventiveness and ability to apply the newest achievements in science and technology to modern products. Creative people need to be able to view things in new ways or from a different perspective. Inventiveness means the power of creative imagination. The goal of science is the pursuit of knowledge for its own sake while the goal of technology is to create products that solve problems and improve human life. Technology is the practical application of science. Creativity There are many definitions of creativity. According to Webster Dictionary, creativity is the ability to make new things or think of new ideas. There are many other definitions, e.g., 1) Creativity is a thought process that involves generating new ideas or concepts or links between existing ideas or concepts; 2) Creativity is the process of developing a new, uncommon or unique idea; 3) Creativity is the ability to generate new ideas, you can learn it, it depends on knowledge, experience, motivation, effort and perseverance; 4) Creativity means creating new combinations from known information. Has anybody ever thought that [1]:  All literature written in contemporary English consists of various combinations of only twenty-six letters;  All images in the world are combinations of only three basic colors: red, yellow and blue;  All music is a composition of up to twelve notes;  All known numbers consist of only ten symbols;  Extremely complex computer calculations are made using two-element systems. That's why, whenever we mention something new, we say in fact, about the innovative arrangement of existing elements. The world of ideas is similar to the world of finance. Investors are active in the financial world, whereas creative people operate in the world of ideas[...]

Incheon Airport Maglev Line DOI:10.15199/48.2019.06.01

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Korea Urban Maglev Program started in December 2006 at Korea Institute of Machinery and Materials (KIMM) in Daejeon. The construction of passenger carrying service of 6.1-km, low-speed Incheon Airport Maglev Line (IAML) started on February 3, 2016. It was preceded by complete and thorough system interface tests, part of which were required by the regulations. The IAML is a completely passive system with attraction electromagnets and primary units of the linear induction motor (LIM) installed in vehicles, while reaction rails for electromagnets and LIMs are installed in the track [1]. The IAML connects Incheon International Airport Transportation Center (IIATC) with Yongyu station in Yeongjong Island. There are 6 stations: (1) IIATC, (2) Long- Term Parking, (3) Administration Complex, (4) International Business Center, (5) Water Park, (6) Yongyu Station. Fig. 1. Route map (red line) of the IAML. Construction The double-track elevated guideways of the IAML are installed on concrete pillars. The highest elevation is 24.5 m, the maximum gradient is 45 ‰ and the minimum curve radius 50 m. There is a maintenance depot and control center in the vicinity of Yongyu Station. The route map is shown in Fig. 1. The trainset on elevated guideway is shown in Fig. 2. The Incheon Airport Transportation Center Stati[...]

Noise of Polyphase Electric Motors

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In 1982, when I started research on noise and vibration in electrical machines, I was very lucky since Professor S.J. Yang's famous book - Low Noise Electrical Motors - [1] had just been published. It was the first book, written in English, dedicated specifically to noise and vibration in electrical machines. Many researchers and engineers have subsequently benefited from the[...]

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