WorldWideScience

Sample records for generalized electric machine

  1. Electric machine

    Science.gov (United States)

    El-Refaie, Ayman Mohamed Fawzi [Niskayuna, NY; Reddy, Patel Bhageerath [Madison, WI

    2012-07-17

    An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

  2. Halbach array motor/generators: A novel generalized electric machine

    Energy Technology Data Exchange (ETDEWEB)

    Merritt, B.T.; Post, R.F.; Dreifuerst, G.R.; Bender, D.A. [Lawrence Livermore National Lab., CA (United States)

    1995-02-01

    For many years Klaus Halbach has been investigating novel designs for permanent magnet arrays, using advanced analytical approaches and employing a keen insight into such systems. One of his motivations for this research was to find more efficient means for the utilization of permanent magnets for use in particle accelerators and in the control of particle beams. As a result of his pioneering work, high power free-electron laser systems, such as the ones built at the Lawrence Livermore Laboratory, became feasible, and his arrays have been incorporated into other particle-focusing systems of various types. This paper reports another, quite different, application of Klaus` work, in the design of high power, high efficiency, electric generators and motors. When tested, these motor/generator systems display some rather remarkable properties. Their success derives from the special properties which these arrays, which the authors choose to call {open_quotes}Halbach arrays,{close_quotes} possess.

  3. Rotating electrical machines

    CERN Document Server

    Le Doeuff, René

    2013-01-01

    In this book a general matrix-based approach to modeling electrical machines is promulgated. The model uses instantaneous quantities for key variables and enables the user to easily take into account associations between rotating machines and static converters (such as in variable speed drives).   General equations of electromechanical energy conversion are established early in the treatment of the topic and then applied to synchronous, induction and DC machines. The primary characteristics of these machines are established for steady state behavior as well as for variable speed scenarios. I

  4. Electrical machines mathematical fundamentals of machine topologies

    CERN Document Server

    Gerling, Dieter

    2015-01-01

    Electrical Machines and Drives play a powerful role in industry with an ever increasing importance. This fact requires the understanding of machine and drive principles by engineers of many different disciplines. Therefore, this book is intended to give a comprehensive deduction of these principles. Special attention is given to the precise mathematical derivation of the necessary formulae to calculate machines and drives and to the discussion of simplifications (if applied) with the associated limits. The book shows how the different machine topologies can be deduced from general fundamentals, and how they are linked together. This book addresses graduate students, researchers, and developers of Electrical Machines and Drives, who are interested in getting knowledge about the principles of machine and drive operation and in detecting the mathematical and engineering specialties of the different machine and drive topologies together with their mutual links. The detailed - but nevertheless compact - mat...

  5. Electrical machines diagnosis

    CERN Document Server

    Trigeassou, Jean-Claude

    2013-01-01

    Monitoring and diagnosis of electrical machine faults is a scientific and economic issue which is motivated by objectives for reliability and serviceability in electrical drives.This book provides a survey of the techniques used to detect the faults occurring in electrical drives: electrical, thermal and mechanical faults of the electrical machine, faults of the static converter and faults of the energy storage unit.Diagnosis of faults occurring in electrical drives is an essential part of a global monitoring system used to improve reliability and serviceability. This diagnosis is perf

  6. Electrical machines & drives

    CERN Document Server

    Hammond, P

    1985-01-01

    Containing approximately 200 problems (100 worked), the text covers a wide range of topics concerning electrical machines, placing particular emphasis upon electrical-machine drive applications. The theory is concisely reviewed and focuses on features common to all machine types. The problems are arranged in order of increasing levels of complexity and discussions of the solutions are included where appropriate to illustrate the engineering implications. This second edition includes an important new chapter on mathematical and computer simulation of machine systems and revised discussions o

  7. Electrical Discharge Machining.

    Science.gov (United States)

    Montgomery, C. M.

    The manual is for use by students learning electrical discharge machining (EDM). It consists of eight units divided into several lessons, each designed to meet one of the stated objectives for the unit. The units deal with: introduction to and advantages of EDM, the EDM process, basic components of EDM, reaction between forming tool and workpiece,…

  8. Electrical machines & their applications

    CERN Document Server

    Hindmarsh, J

    1984-01-01

    A self-contained, comprehensive and unified treatment of electrical machines, including consideration of their control characteristics in both conventional and semiconductor switched circuits. This new edition has been expanded and updated to include material which reflects current thinking and practice. All references have been updated to conform to the latest national (BS) and international (IEC) recommendations and a new appendix has been added which deals more fully with the theory of permanent-magnets, recognising the growing importance of permanent-magnet machines. The text is so arra

  9. Design of rotating electrical machines

    CERN Document Server

    Pyrhonen , Juha; Hrabovcova , Valeria

    2013-01-01

    In one complete volume, this essential reference presents an in-depth overview of the theoretical principles and techniques of electrical machine design. This timely new edition offers up-to-date theory and guidelines for the design of electrical machines, taking into account recent advances in permanent magnet machines as well as synchronous reluctance machines. New coverage includes: Brand new material on the ecological impact of the motors, covering the eco-design principles of rotating electrical machinesAn expanded section on the design of permanent magnet synchronous machines, now repo

  10. Electrical machines with Matlab

    CERN Document Server

    Gonen, Turan

    2011-01-01

    Basic ConceptsDistribution SystemImpact of Dispersed Storage and GenerationBrief Overview of Basic Electrical MachinesReal and Reactive Powers in Single-Phase AC CircuitsThree-Phase CircuitsThree-Phase SystemsUnbalanced Three-Phase LoadsMeasurement of Average Power in Three-Phase CircuitsPower Factor CorrectionMagnetic CircuitsMagnetic Field of Current-Carrying ConductorsAmpère's Magnetic Circuital LawMagnetic CircuitsMagnetic Circuit with Air GapBrief Review of FerromagnetismMagnetic Core LossesHow to Determine Flux for a Given MMFPermanent MagnetsTransformersTransformer ConstructionBrief Rev

  11. Modeling of electrical machines with a view to their control: general concepts (EGEM, electrical engineering series); Modelisation des machines electriques en vue de leur commande: Concepts generaux (Traite EGEM, serie Genie electrique)

    Energy Technology Data Exchange (ETDEWEB)

    Louis, J.P.

    2004-07-01

    Electrical actuators are present in automatized factories, in transportation systems and in many devices of the everyday life. They must be controlled in order to get an intelligent behaviour. Control systems are based on a good knowledge of actuators, electrical machines and static converters. This knowledge is condensed in models which are based on physical laws but also on hypotheses which have to be discussed (linearity, first harmonics, symmetry). These properties are used in direct models from which the inverse models are deduced and are at the origin of control algorithms. This book deals with the general concepts of the modeling of electrical machines. The analysis, simulation and synthesis of control laws is based on dynamical models used in automation (frequency and state models). The most relevant models are based on the vectorial properties of the physical models which lead to the most commonly used transformations: Clarke, Concordia, Fortescue, Lyon, Ku and Park. (J.S.)

  12. Non-conventional electrical machines

    CERN Document Server

    Rezzoug, Abderrezak

    2013-01-01

    The developments of electrical machines are due to the convergence of material progress, improved calculation tools, and new feeding sources. Among the many recent machines, the authors have chosen, in this first book, to relate the progress in slow speed machines, high speed machines, and superconducting machines. The first part of the book is dedicated to materials and an overview of magnetism, mechanic, and heat transfer.

  13. Electrical discharge machining in dentistry.

    Science.gov (United States)

    Van Roekel, N B

    1992-01-01

    A brief history of electrical discharge machining (EDM) is given and the process is discussed. A description of the application of EDM for fabricating precision attachment removable partial dentures, fixed-removable implant prostheses, and titanium-ceramic crowns is presented. The advantages and disadvantages of the EDM process for the dental profession are evaluated. Although expensive, the procedure has merit.

  14. Electrical machines and drives

    CERN Document Server

    Hindmarsh, John

    2002-01-01

    Recent years have brought substantial developments in electrical drive technology, with the appearance of highly rated, very-high-speed power-electronic switches, combined with microcomputer control systems.This popular textbook has been thoroughly revised and updated in the light of these changes. It retains its successful formula of teaching through worked examples, which are put in context with concise explanations of theory, revision of equations and discussion of the engineering implications. Numerous problems are also provided, with answers supplied.The third edition in

  15. Magnet management in electric machines

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, Patel Bhageerath; El-Refaie, Ayman Mohamed Fawzi; Huh, Kum Kang

    2017-03-21

    A magnet management method of controlling a ferrite-type permanent magnet electrical machine includes receiving and/or estimating the temperature permanent magnets; determining if that temperature is below a predetermined temperature; and if so, then: selectively heating the magnets in order to prevent demagnetization and/or derating the machine. A similar method provides for controlling magnetization level by analyzing flux or magnetization level. Controllers that employ various methods are disclosed. The present invention has been described in terms of specific embodiment(s), and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.

  16. Magnet management in electric machines

    Science.gov (United States)

    Reddy, Patel Bhageerath; El-Refaie, Ayman Mohamed Fawzi; Huh, Kum Kang

    2017-03-21

    A magnet management method of controlling a ferrite-type permanent magnet electrical machine includes receiving and/or estimating the temperature permanent magnets; determining if that temperature is below a predetermined temperature; and if so, then: selectively heating the magnets in order to prevent demagnetization and/or derating the machine. A similar method provides for controlling magnetization level by analyzing flux or magnetization level. Controllers that employ various methods are disclosed. The present invention has been described in terms of specific embodiment(s), and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims.

  17. Recycling rotating electrical machines

    Directory of Open Access Journals (Sweden)

    Rafael Hernández-Millán

    2017-01-01

    Full Text Available Este trabajo establece los principios de diseño para el reciclaje de máquinas eléctricas rotativas (sincrónicas y de inducción, en otras palabras, las máquinas eléctricas y sus componentes pueden ser reutilizados. Además, se cubren temas tecnológicos surgidos de las siguientes componentes de la máquina: núcleo del estator y rotor, devanados del estator y rotor, cojinetes, ejes, y carcasas. Los principios de diseño discutidos pueden extenderse a los transformadores. Este trabajo no consideró materiales de aislamiento en devanados de alta tensión. La economía de reciclaje no se discute ni consecuencias ambientales. Las máquinas rotativas consideradas en el presente estudio son de un rango de potencia entre 0,1 kW a 400 kW, frecuencias de 50 hertz y 60 hertz y polos 2, 4 y 6, aunque los conceptos generales podrían aplicarse a otras máquinas. Se discuten las normas de máquina necesarios para lograr estos objetivos, que abarca: velocidad, tensión nominal, capacidades, formas, dimensiones, de aislamiento, de los devanados, cojinetes, ejes y carcasas.

  18. Rotating Drive for Electrical-Arc Machining

    Science.gov (United States)

    Fransen, C. D.

    1986-01-01

    Rotating drive improves quality of holes made by electrical-arc machining. Mechanism (Uni-tek, rotary head, or equivalent) attached to electrical-arc system. Drive rotates electrode as though it were mechanical drill, while an arc disintegrates metal in workpiece, thereby creating hole. Rotating electrode method often used in electric-discharge machining. NASA innovation is application of technique to electrical-arc machining.

  19. Rotating electrical machines: Poynting flow

    Science.gov (United States)

    Donaghy-Spargo, C.

    2017-09-01

    This paper presents a complementary approach to the traditional Lorentz and Faraday approaches that are typically adopted in the classroom when teaching the fundamentals of electrical machines—motors and generators. The approach adopted is based upon the Poynting vector, which illustrates the ‘flow’ of electromagnetic energy. It is shown through simple vector analysis that the energy-flux density flow approach can provide insight into the operation of electrical machines and it is also shown that the results are in agreement with conventional Maxwell stress-based theory. The advantage of this approach is its complementary completion of the physical picture regarding the electromechanical energy conversion process—it is also a means of maintaining student interest in this subject and as an unconventional application of the Poynting vector during normal study of electromagnetism.

  20. Setup Aid for Electrical-Discharge Machining

    Science.gov (United States)

    Lines, G.; Duca, J.

    1985-01-01

    Interlock assures that workpiece is correctly assembled in machining fixture. A Plunger in a Hollow Shaft actuates a switch, allowing a power supply to produce current for electrical-discharge machining. Plunger operates only when necessary parts are position.

  1. Electric machine for hybrid motor vehicle

    Science.gov (United States)

    Hsu, John Sheungchun

    2007-09-18

    A power system for a motor vehicle having an internal combustion engine and an electric machine is disclosed. The electric machine has a stator, a permanent magnet rotor, an uncluttered rotor spaced from the permanent magnet rotor, and at least one secondary core assembly. The power system also has a gearing arrangement for coupling the internal combustion engine to wheels on the vehicle thereby providing a means for the electric machine to both power assist and brake in relation to the output of the internal combustion engine.

  2. Electroformed Electrodes for Electrical-Discharge Machining

    Science.gov (United States)

    Werner, A.; Cassidenti, M.

    1984-01-01

    Copper electrodes replace graphite electrodes in many instances of electrical-discharge machining (EDM) of complex shapes. Copper electrodes wear longer and cause less contamination of EDM dielectric fluid than do graphite electrodes.

  3. Contamination-Free Electrical-Discharge Machining

    Science.gov (United States)

    Schmidt, Mark G.

    1987-01-01

    Contamination of parts by electrical-discharge machining (EDM) almost completely eliminated by reversing flow of coolant. Flow reversed from usual direction so coolant carries contaminants out through passage in electrode. Coolant for reverse flow is pressurized dichlorodifluoromethane vapor.

  4. Electrical-Discharge Machining Of Perpendicular Passages

    Science.gov (United States)

    Malinzak, R. Michael; Booth, Gary N.

    1996-01-01

    Perpendicular telescoping electrode used to perform electrical-discharge machining (EDM) of internal passage through previously inaccessible depth of metal workpiece. More specifically, used to make internal passage perpendicular to passage entering from outer surface.

  5. Multi-winding homopolar electric machine

    Science.gov (United States)

    Van Neste, Charles W

    2012-10-16

    A multi-winding homopolar electric machine and method for converting between mechanical energy and electrical energy. The electric machine includes a shaft defining an axis of rotation, first and second magnets, a shielding portion, and a conductor. First and second magnets are coaxial with the shaft and include a charged pole surface and an oppositely charged pole surface, the charged pole surfaces facing one another to form a repulsive field therebetween. The shield portion extends between the magnets to confine at least a portion of the repulsive field to between the first and second magnets. The conductor extends between first and second end contacts and is toroidally coiled about the first and second magnets and the shield portion to develop a voltage across the first and second end contacts in response to rotation of the electric machine about the axis of rotation.

  6. Advanced Electrical Machines and Machine-Based Systems for Electric and Hybrid Vehicles

    Directory of Open Access Journals (Sweden)

    Ming Cheng

    2015-09-01

    Full Text Available The paper presents a number of advanced solutions on electric machines and machine-based systems for the powertrain of electric vehicles (EVs. Two types of systems are considered, namely the drive systems designated to the EV propulsion and the power split devices utilized in the popular series-parallel hybrid electric vehicle architecture. After reviewing the main requirements for the electric drive systems, the paper illustrates advanced electric machine topologies, including a stator permanent magnet (stator-PM motor, a hybrid-excitation motor, a flux memory motor and a redundant motor structure. Then, it illustrates advanced electric drive systems, such as the magnetic-geared in-wheel drive and the integrated starter generator (ISG. Finally, three machine-based implementations of the power split devices are expounded, built up around the dual-rotor PM machine, the dual-stator PM brushless machine and the magnetic-geared dual-rotor machine. As a conclusion, the development trends in the field of electric machines and machine-based systems for EVs are summarized.

  7. A Simple and General Approach to Determination of Self and Mutual Inductances for AC machines

    DEFF Research Database (Denmark)

    Lu, Kaiyuan; Rasmussen, Peter Omand; Ritchie, Ewen

    2011-01-01

    Modelling of AC electrical machines plays an important role in electrical engineering education related to electrical machine design and control. One of the fundamental requirements in AC machine modelling is to derive the self and mutual inductances, which could be position dependant. Theories...... developed so far for inductance determination are often associated with complicated machine magnetic field analysis, which exhibits a difficulty for most students. This paper describes a simple and general approach to the determination of self and mutual inductances of different types of AC machines. A new...... determination are given for a 3-phase, salient-pole synchronous machine, and an induction machine....

  8. Torque ripple reduction in electric machines

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, Patel Bhageerath; Huh, Kum-Kang; El-Refaie, Ayman Mohamed Fawzi; Galioto, Steven Joseph

    2017-08-22

    An electric machine, such as an Internal Permanent magnet or Synchronous Reluctance machine, having X phases, that includes a stator assembly, having M slots, with a stator core and stator teeth, that is further configured with stator windings to generate a stator magnetic field when excited with alternating currents and extends along a longitudinal axis with an inner surface that defines a cavity; and a rotor assembly, having N poles, disposed within the cavity which is configured to rotate about the longitudinal axis, wherein the rotor assembly includes a shaft, a rotor core located circumferentially around the shaft. The machine is configured such that a value k=M/(X*N) wherein k is a non-integer greater than about 1.3. The electric machine may alternatively, or additionally, include a non-uniformed gap between the exterior surface of the rotor spokes and the interior stator surface of the stator.

  9. Mitigation of vibration in large electrical machines

    OpenAIRE

    Shahaj, Annabel

    2010-01-01

    In this study two new technologies are investigated with a view to improving the efficiency and reducing the vibrations of large electrical machines. These machines are used for high powered industrial applications. Individually controlled conductors are part of an active stator project that Converteam Ltd are developing. This involves individual conductors located in each stator slot that can be controlled separately. These replace traditional polyphase windings in order to provide a hi...

  10. Electrical-Discharge Machining With Additional Axis

    Science.gov (United States)

    Malinzak, Roger M.; Booth, Gary N.

    1991-01-01

    Proposed electrical-discharge-machining (EDM) apparatus uses moveable vertical wire as electrode. Wire positionable horizontally along one axis as it slides vertically past workpiece. Workpiece indexed in rotation about horizontal axis. Because of symmetry of parts, process used to make two such parts at a time by defining boundary between them. Advantages: cost of material reduced, imparts less residual stress to workpiece, and less time spent machining each part when parts produced in such symmetrical pairs.

  11. Apparatus for cooling an electric machine

    Science.gov (United States)

    Palafox, Pepe; Gerstler, William Dwight; Shen, Xiaochun; El-Refaie, Ayman Mohamed Fawzi; Lokhandwalla, Murtuza; Salasoo, Lembit

    2013-07-16

    Provided is an apparatus, for example, for use with a rotating electric machine, that includes a housing. The housing can include a housing main portion and a housing end portion. The housing main portion can be configured to be disposed proximal to a body portion of a stator section of an electric machine. The housing main portion can define a main fluid channel that is configured to conduct fluid therethrough. The housing end portion can receive fluid from said main fluid channel and direct fluid into contact with a winding end portion of a conductive winding of the stator section.

  12. High slot utilization systems for electric machines

    Science.gov (United States)

    Hsu, John S

    2009-06-23

    Two new High Slot Utilization (HSU) Systems for electric machines enable the use of form wound coils that have the highest fill factor and the best use of magnetic materials. The epoxy/resin/curing treatment ensures the mechanical strength of the assembly of teeth, core, and coils. In addition, the first HSU system allows the coil layers to be moved inside the slots for the assembly purpose. The second system uses the slided-in teeth instead of the plugged-in teeth. The power density of the electric machine that uses either system can reach its highest limit.

  13. Electrical machine PWM loss evaluation basics

    Energy Technology Data Exchange (ETDEWEB)

    Ruderman, A. [The School of Engineering, Bar-Ilan Univ., Ramat-Gan (Israel); Welch, R. Jr. [IEEE, Welch Enterprise, Oakdale (United States)

    2005-07-01

    Modern power converters utilize pulse-width modulation (PWM) voltage control. Output voltage high frequency harmonics induce additional electrical machine loss. As there is no accepted PWM loss theory, PWM loss is usually accounted for by machine power de-rating. In-depth understanding of PWM loss mechanisms is important for predicting losses and improving energy efficiency of electrical machines. In this paper we suggest a new time domain PWM loss approach. It assumes that PWM eddy current iron loss dominates over PWM copper and hysteresis iron losses and comprises theoretical normalized PWM loss evaluation and experimental characterization. Once maximal PWM loss is measured, it can be scaled for an arbitrary operating point using simple formula. Theoretical results are shown to be in a good agreement with a published experimental data. (orig.)

  14. Prosthesis fabrication using electrical discharge machining.

    Science.gov (United States)

    Van Roekel, N B

    1992-01-01

    Fixed-removable implant prostheses provide solutions for some of the problems associated with implant dentistry, especially in the maxilla. The technique for using electrical discharge machining to create a precise passive fit between the substructure bar and the removable suprastructure is presented. The advantages, disadvantages, and complications associated with this type of prosthesis are discussed.

  15. Monitor For Electrical-Discharge Machining

    Science.gov (United States)

    Burley, Richard K.

    1993-01-01

    Circuit monitors electrical-discharge-machining (EDM) process to detect and prevent abnormal arcing, which can produce unacceptable "burn" marks on workpiece. When voltage between EDM electrode and workpiece behaves in manner indicative of abnormal arcing, relay made to switch off EDM power, which remains off until operator attends to EDM setup and resets monitor.

  16. Electrical-Discharge Machining Of Curved Passages

    Science.gov (United States)

    Guirguis, Kamal S.

    1993-01-01

    Electrical-discharge machining (EDM) used to cut deep hole with bends. EDM process done with articulating segmented electrode. Originally straight, electrode curved as it penetrates part, forming long, smoothly curving hole. After hole cut, honed with slurry to remove thin layer of recast metal created by EDM. Breakage of tools, hand deburring, and drilling debris eliminated.

  17. Six-Axis Electrical-Discharge Machine

    Science.gov (United States)

    Werner, A. R.

    1983-01-01

    Electrical discharge machine (EDM) of unusual versitility made by conversion of radial drill. Drilling head is replaced by ram that holds and positions electrode. Tank and recirculation system for coolant are added. EDM has six independent motions and drastically reduced cost of manufacturing. New applications are constantly being found.

  18. Sensorless Suitability Analysis of Hybrid PM Machines for Electric Vehicles

    DEFF Research Database (Denmark)

    Matzen, Torben Nørregaard; Rasmussen, Peter Omand

    2009-01-01

    Electrical machines for traction in electric vehicles are an essential component which attract attention with respect to machine design and control as a part of the emerging renewable industry. For the hybrid electric machine to replace the familiar behaviour of the combustion engine torque...

  19. Preset Electrodes for Electrical-Discharge Machining

    Science.gov (United States)

    Coker, Bill E.

    1987-01-01

    New electrode holder for electrical-discharge machining (EDM) provides for repeatable loading and setting of many electrodes. New holder is rotating-index tool carrying six, eight, or more electrodes. Before use, all electrodes set with aid of ring surrounding tool, and locked in position with screws. When electrode replaced, EDM operator pulls spring-loaded pin on tool so it rotates about center pin. Fresh electrode then rotated into position against workpiece.

  20. A Simple and General Approach to Determination of Self and Mutual Inductances for AC machines

    DEFF Research Database (Denmark)

    Lu, Kaiyuan; Rasmussen, Peter Omand; Ritchie, Ewen

    2011-01-01

    Modelling of AC electrical machines plays an important role in electrical engineering education related to electrical machine design and control. One of the fundamental requirements in AC machine modelling is to derive the self and mutual inductances, which could be position dependant. Theories...... developed so far for inductance determination are often associated with complicated machine magnetic field analysis, which exhibits a difficulty for most students. This paper describes a simple and general approach to the determination of self and mutual inductances of different types of AC machines. A new...

  1. Influence of electrical resistivity and machining parameters on electrical discharge machining performance of engineering ceramics.

    Science.gov (United States)

    Ji, Renjie; Liu, Yonghong; Diao, Ruiqiang; Xu, Chenchen; Li, Xiaopeng; Cai, Baoping; Zhang, Yanzhen

    2014-01-01

    Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM) is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engineering ceramics is higher, and there has been no research on the relationship between the EDM parameters and the electrical resistivity of the engineering ceramics. This paper investigates the effects of the electrical resistivity and EDM parameters such as tool polarity, pulse interval, and electrode material, on the ZnO/Al2O3 ceramic's EDM performance, in terms of the material removal rate (MRR), electrode wear ratio (EWR), and surface roughness (SR). The results show that the electrical resistivity and the EDM parameters have the great influence on the EDM performance. The ZnO/Al2O3 ceramic with the electrical resistivity up to 3410 Ω·cm can be effectively machined by EDM with the copper electrode, the negative tool polarity, and the shorter pulse interval. Under most machining conditions, the MRR increases, and the SR decreases with the decrease of electrical resistivity. Moreover, the tool polarity, and pulse interval affect the EWR, respectively, and the electrical resistivity and electrode material have a combined effect on the EWR. Furthermore, the EDM performance of ZnO/Al2O3 ceramic with the electrical resistivity higher than 687 Ω·cm is obviously different from that with the electrical resistivity lower than 687 Ω·cm, when the electrode material changes. The microstructure character analysis of the machined ZnO/Al2O3 ceramic surface shows that the ZnO/Al2O3 ceramic is removed by melting, evaporation and thermal spalling, and the material from the working fluid and the graphite electrode can transfer to the workpiece surface during electrical discharge

  2. Influence of electrical resistivity and machining parameters on electrical discharge machining performance of engineering ceramics.

    Directory of Open Access Journals (Sweden)

    Renjie Ji

    Full Text Available Engineering ceramics have been widely used in modern industry for their excellent physical and mechanical properties, and they are difficult to machine owing to their high hardness and brittleness. Electrical discharge machining (EDM is the appropriate process for machining engineering ceramics provided they are electrically conducting. However, the electrical resistivity of the popular engineering ceramics is higher, and there has been no research on the relationship between the EDM parameters and the electrical resistivity of the engineering ceramics. This paper investigates the effects of the electrical resistivity and EDM parameters such as tool polarity, pulse interval, and electrode material, on the ZnO/Al2O3 ceramic's EDM performance, in terms of the material removal rate (MRR, electrode wear ratio (EWR, and surface roughness (SR. The results show that the electrical resistivity and the EDM parameters have the great influence on the EDM performance. The ZnO/Al2O3 ceramic with the electrical resistivity up to 3410 Ω·cm can be effectively machined by EDM with the copper electrode, the negative tool polarity, and the shorter pulse interval. Under most machining conditions, the MRR increases, and the SR decreases with the decrease of electrical resistivity. Moreover, the tool polarity, and pulse interval affect the EWR, respectively, and the electrical resistivity and electrode material have a combined effect on the EWR. Furthermore, the EDM performance of ZnO/Al2O3 ceramic with the electrical resistivity higher than 687 Ω·cm is obviously different from that with the electrical resistivity lower than 687 Ω·cm, when the electrode material changes. The microstructure character analysis of the machined ZnO/Al2O3 ceramic surface shows that the ZnO/Al2O3 ceramic is removed by melting, evaporation and thermal spalling, and the material from the working fluid and the graphite electrode can transfer to the workpiece surface during electrical

  3. MICRO ELECTRICAL DISCHARGE MACHINING DEPOSITION IN AIR

    Institute of Scientific and Technical Information of China (English)

    JIN Baidong; ZHAO Wansheng; WANG Zhenlong; CAO Guohui

    2006-01-01

    A new deposition method is described using micro electrical discharge machining (EDM)to deposit tool electrode material on workpiece in air. The basic principles of micro electrical discharge deposition (EDD) are analyzed and the realized conditions are predicted. With an ordinary EDM shaping machine, brass as the electrode, high-speed steel as the workpiece, a lot of experiments are carried out on micro EDD systematically and thoroughly. The effects of major processing parameters, such as the discharge current, discharge duration, pulse interval and working medium, are obtained. As a result, a micro cylinder with 0.19 mm in diameter and 7.35 mm in height is deposited.By exchanging the polarities of the electrode and workpiece the micro cylinder can be removed selectively. So the reversible machining of deposition and removal is achieved, which breaks through the constraint of traditional EDM. Measurements show that the deposited material is compact and close to workpiece base, whose components depend on the tool electrode material.

  4. Thermal models of electric machines with dynamic workloads

    Directory of Open Access Journals (Sweden)

    Christian Pohlandt

    2015-07-01

    Full Text Available Electric powertrains are increasingly used in off-highway machines because of easy controllability and excellent overall efficiency. The main goals are increasing the energy efficiency of the machine and the optimization of the work process. The thermal behaviour of electric machines with dynamic workloads applied to is a key design factor for electric powertrains in off-highway machines. This article introduces a methodology to model the thermal behaviour of electric machines. Using a noncausal modelling approach, an electric powertrain is analysed for dynamic workloads. Cause-effect relationships and reasons for increasing temperature are considered as well as various cooling techniques. The validation of the overall simulation model of the powertrain with measured field data workloads provides convincing results to evaluate numerous applications of electric machines in off-highway machines.

  5. Linear electric machines, drives, and MAGLEVs handbook

    CERN Document Server

    Boldea, Ion

    2013-01-01

    Based on author Ion Boldea's 40 years of experience and the latest research, Linear Electric Machines, Drives, and Maglevs Handbook provides a practical and comprehensive resource on the steady improvement in this field. The book presents in-depth reviews of basic concepts and detailed explorations of complex subjects, including classifications and practical topologies, with sample results based on an up-to-date survey of the field. Packed with case studies, this state-of-the-art handbook covers topics such as modeling, steady state, and transients as well as control, design, and testing of li

  6. Ultrasonic Vibration Electrical Discharge Machining in Gas

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new method of ultrasonic vibration electrical discharge machining(UEDM) in gas is proposed in this paper. In UEDM in gas, the gap between tool electrode and workpiece is small(about 0.01mm), and the voltage between them is higher than EDM in liquid, so short circuit is easy to take place. It is very important for improving the MRR to avoid short circuit. Therefore, some measures have been taken, a rotation and a planetary motion are superimposed upon the tool electrode. During UEDM in gas, workpiece is vi...

  7. Electric machine and current source inverter drive system

    Science.gov (United States)

    Hsu, John S

    2014-06-24

    A drive system includes an electric machine and a current source inverter (CSI). This integration of an electric machine and an inverter uses the machine's field excitation coil for not only flux generation in the machine but also for the CSI inductor. This integration of the two technologies, namely the U machine motor and the CSI, opens a new chapter for the component function integration instead of the traditional integration by simply placing separate machine and inverter components in the same housing. Elimination of the CSI inductor adds to the CSI volumetric reduction of the capacitors and the elimination of PMs for the motor further improve the drive system cost, weight, and volume.

  8. Electric vehicle machines and drives design, analysis and application

    CERN Document Server

    Chau, K

    2015-01-01

    A timely comprehensive reference consolidates the research and development of electric vehicle machines and drives for electric and hybrid propulsions • Focuses on electric vehicle machines and drives • Covers the major technologies in the area including fundamental concepts and applications • Emphasis the design criteria, performance analyses and application examples or potentials of various motor drives and machine systems • Accompanying website includes the simulation models and outcomes as supplementary material

  9. Generalized theory of mixed pole machines with a general rotor configuration

    Directory of Open Access Journals (Sweden)

    Ayman S. Abdel-khalik

    2013-03-01

    Full Text Available This paper introduces a generalized theory for the operation of mixed pole machines (MPMs. The MPM has two stator windings, namely the main winding with pole pairs P1 and the control winding with pole pairs P2. The MPM has shown promise in the field of adjustable speed drives for large machines and in the field of wind energy electrical generation. The operation of MPM relies on the interaction between the two fields produced by the two stator windings through the intermediate action of a specially designed rotor (nested-cage or reluctance rotor. The machine theory is described from a physical aspect rather than mathematical derivations. A simple representation is also presented, from which the machine d–q model can be readily deduced. The effect of mechanical loading on the relative positions of the machine fields is also presented.

  10. Influence of Electric Discharges on Bearings of Electric Machines

    Directory of Open Access Journals (Sweden)

    Karel Chmelik

    2006-01-01

    Full Text Available I the last time many articles were found out discussed about shaft voltage, bearing currents and their influence on lifetime and reliability of electric machines bearings. This is associated with extension of use of static converters for control drives for DC motors feeding in the past and for induction motors feeding from frequency converters in the last time. It is known from our own experiences that not all failures assigned to bearing currents were their real reason and we also know how hardly the mentioned currents can be measured on real machines and how work-intensive and expensive is to detect real reason of the failure on damaged bearing. We will not concern with basics of classical bearing currents in this paper, because they were known and studied in the beginning of the last century but our own investigations will be presented.

  11. electrical-thermal coupling of induction machine for improved ...

    African Journals Online (AJOL)

    user

    The interaction of its electrical and mechanical parts leads to an increase in temperature which if not properly ... Keywords: induction machine, electrical model, mechanical model, thermal model, ..... is the geometry, material constraints and the.

  12. Passivity-Based Control of Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Nicklasson, P.J.

    1996-12-31

    This doctoral thesis presents new results on the design and analysis of controllers for a class of electric machines. Nonlinear controllers are derived from a Lagrangian model representation using passivity techniques, and previous results on induction motors are improved and extended to Blondel-Park transformable machines. The relation to conventional techniques is discussed, and it is shown that the formalism introduced in this work facilitates analysis of conventional methods, so that open questions concerning these methods may be resolved. In addition, the thesis contains the following improvements of previously published results on the control of induction motors: (1) Improvement of a passivity-based speed/position controller, (2) Extension of passivity-based (observer-less and observer-based) controllers from regulation to tracking of rotor flux norm, (3) An extension of the classical indirect FOC (Field-Oriented Control) scheme to also include global rotor flux norm tracking, instead of only torque tracking and rotor flux norm regulation. The design is illustrated experimentally by applying the proposed control schemes to a squirrel-cage induction motor. The results show that the proposed methods have advantages over previous designs with respect to controller tuning, performance and robustness. 145 refs., 21 figs.

  13. Support vector machine for day ahead electricity price forecasting

    Science.gov (United States)

    Razak, Intan Azmira binti Wan Abdul; Abidin, Izham bin Zainal; Siah, Yap Keem; Rahman, Titik Khawa binti Abdul; Lada, M. Y.; Ramani, Anis Niza binti; Nasir, M. N. M.; Ahmad, Arfah binti

    2015-05-01

    Electricity price forecasting has become an important part of power system operation and planning. In a pool- based electric energy market, producers submit selling bids consisting in energy blocks and their corresponding minimum selling prices to the market operator. Meanwhile, consumers submit buying bids consisting in energy blocks and their corresponding maximum buying prices to the market operator. Hence, both producers and consumers use day ahead price forecasts to derive their respective bidding strategies to the electricity market yet reduce the cost of electricity. However, forecasting electricity prices is a complex task because price series is a non-stationary and highly volatile series. Many factors cause for price spikes such as volatility in load and fuel price as well as power import to and export from outside the market through long term contract. This paper introduces an approach of machine learning algorithm for day ahead electricity price forecasting with Least Square Support Vector Machine (LS-SVM). Previous day data of Hourly Ontario Electricity Price (HOEP), generation's price and demand from Ontario power market are used as the inputs for training data. The simulation is held using LSSVMlab in Matlab with the training and testing data of 2004. SVM that widely used for classification and regression has great generalization ability with structured risk minimization principle rather than empirical risk minimization. Moreover, same parameter settings in trained SVM give same results that absolutely reduce simulation process compared to other techniques such as neural network and time series. The mean absolute percentage error (MAPE) for the proposed model shows that SVM performs well compared to neural network.

  14. Trends in Wire Electrical Discharge Machining (WEDM: A Review

    Directory of Open Access Journals (Sweden)

    Ms. Sharanya S. Nair

    2014-12-01

    Full Text Available The exponential growth of manufacturing industries and production and the increased need of accuracy and precision throws the spotlight on the nontraditional machining processes. The machining of metals and nonmetals having special properties like high strength, high hardness and toughness is done by non- conventional machining methods. Wire electrical discharge machining is one of the earliest non-traditional machining processes. This machining process competes with conventional machining such as milling, broaching, grinding etc. However, its ability to cut extremely intricate and delicate shapes with utmost accuracy makes this process most suitable among all other processes. The otherwise hard to be machined materials like carbides, tungsten, zirconium etc. can be easily machined using this process. This paper reviews notable work done in the field of WEDM by various researchers.

  15. The Electrical and Mechanical Alignment and Accuracy Detection of Numerial Control Machine Tool

    Institute of Scientific and Technical Information of China (English)

    XU Liang-xiong; ZHOU Xiang

    2012-01-01

    In the work of numerical control reformation of general machine tool, the installation and debugging of machine tool is a crucial part. For the C6132 machine tool, and make the use of electrical and mechanical alignment, parameter adjusting, numerical control lathe accuracy debugging and performance examination has been used to finish a series of tailing in the work of numerical control reformation of general machine tool. In this paper, the detailed process of electrical and mechanical alignment, parameter adjusting, numerical control lathe accuracy debugging and performance examination has been demonstrated, meanwhile, the specific operational approach of these work programs has been discussed. Therefore, the present results provides essential reference and approach for the numerical control reformation of general machine tool.

  16. Metal release from coffee machines and electric kettles.

    Science.gov (United States)

    Müller, Frederic D; Hackethal, Christin; Schmidt, Roman; Kappenstein, Oliver; Pfaff, Karla; Luch, Andreas

    2015-01-01

    The release of elemental ions from 8 coffee machines and 11 electric kettles into food simulants was investigated. Three different types of coffee machines were tested: portafilter espresso machines, pod machines and capsule machines. All machines were tested subsequently on 3 days before and on 3 days after decalcification. Decalcification of the machines was performed with agents according to procedures as specified in the respective manufacturer's manuals. The electric kettles showed only a low release of the elements analysed. For the coffee machines decreasing concentrations of elements were found from the first to the last sample taken in the course of 1 day. Metal release on consecutive days showed a decreasing trend as well. After decalcification a large increase in the amounts of elements released was encountered. In addition, the different machine types investigated clearly differed in their extent of element release. By far the highest leaching, both quantitatively and qualitatively, was found for the portafilter machines. With these products releases of Pb, Ni, Mn, Cr and Zn were in the range and beyond the release limits as proposed by the Council of Europe. Therefore, a careful rinsing routine, especially after decalcification, is recommended for these machines. The comparably lower extent of release of one particular portafilter machine demonstrates that metal release at levels above the threshold that triggers health concerns are technically avoidable.

  17. Electric machines steady state, transients, and design with Matlab

    CERN Document Server

    Boldea, Ion

    2009-01-01

    Part I: Steady StateIntroductionElectric Energy and Electric MachinesBasic Types of Transformers and Electric MachinesLosses and EfficiencyPhysical Limitations and RatingsNameplate RatingsMethods of AnalysisState of the Art and Perspective Electric TransformersAC Coil with Magnetic Core and Transformer Principles Magnetic Materials in EMs and Their LossesElectric Conductors and Their Skin EffectsComponents of Single- and 3-Phase TransformersFlux Linkages and Inductances of Single-Phase TransformersCircuit Equations of Single-Phase Transformers With Core LossesSteady State and Equivalent Circui

  18. Wire electric-discharge machining and other fabrication techniques

    Science.gov (United States)

    Morgan, W. H.

    1983-01-01

    Wire electric discharge machining and extrude honing were used to fabricate a two dimensional wing for cryogenic wind tunnel testing. Electric-discharge cutting is done with a moving wire electrode. The cut track is controlled by means of a punched-tape program and the cutting feed is regulated according to the progress of the work. Electric-discharge machining involves no contact with the work piece, and no mechanical force is exerted. Extrude hone is a process for honing finish-machined surfaces by the extrusion of an abrasive material (silly putty), which is forced through a restrictive fixture. The fabrication steps are described and production times are given.

  19. Superconducting Electric Machines for Ship Propulsion.

    Science.gov (United States)

    1977-02-14

    ship propulsion applications. These concepts evolved from previous work at MIT on superconducting AC machines. The superconducting machines considered were: (1) multipole, low-speed motors, (2) torque compensated motors, (3) high-speed generator, (4) rotating air-gap armature induction motor, (5) thyristor switched AC motors. The first four machine types were studied theoretically while experimental models were constructed of the last two. Preliminary designs were completed...of the five mahcines for an appropriate ship ... propulsion application. In

  20. Three-dimensional machining of insulating ceramics materials with electrical discharge machining

    Institute of Scientific and Technical Information of China (English)

    Yasushi FUKUZAWA; Naotake MOHRI; Hiromitsu GOTOH; Takayuki TANI

    2009-01-01

    The insulating ceramics were processed with sinking and wire cut electrical discharge machining(EDM). The new technology was named as the assisting electrode method. In the machining, the electrical conductive material was adhered on the surface of insulating workpiece as the starting point of electrical discharge. As the processing operated in oil, the electrical conductive product composed of decomposition carbon element from working oil adhered on the workpiece during discharge. The discharges generated continuously with the formation of the electrical conductive layer. So, the insulating ceramics turn to the machinable material by EDM. We introduced the mechanism and the application of the machining of insulating ceramics such as Si3N4 and ZrO2.

  1. Electric machine and current source inverter drive system

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, John S

    2014-06-24

    A drive system includes an electric machine and a current source inverter (CSI). This integration of an electric machine and an inverter uses the machine's field excitation coil for not only flux generation in the machine but also for the CSI inductor. This integration of the two technologies, namely the U machine motor and the CSI, opens a new chapter for the component function integration instead of the traditional integration by simply placing separate machine and inverter components in the same housing. Elimination of the CSI inductor adds to the CSI volumetric reduction of the capacitors and the elimination of PMs for the motor further improve the drive system cost, weight, and volume.

  2. Effect of machining fluid on the process performance of wire electrical discharge machining of nanocomposite ceramic

    Directory of Open Access Journals (Sweden)

    Zhang Chengmao

    2015-01-01

    Full Text Available Wire electric discharge machining (WEDM promise to be effective and economical techniques for the production of tools and parts from conducting ceramic blanks. However, the manufacturing of nanocomposite ceramics blanks with these processes is a long and costly process. This paper presents a new process of machining nanocomposite ceramics using WEDM. WEDM uses water based emulsion, polyvinyl alcohol and distilled water as the machining fluid. Machining fluid is a primary factor that affects the material removal rate and surface quality of WEDM. The effects of emulsion concentration, polyvinyl alcohol concentration and distilled water of the machining fluid on the process performance have been investigated.

  3. Experimental Investigation of process parameters influence on machining Inconel 800 in the Electrical Spark Eroding Machine

    Science.gov (United States)

    Karunakaran, K.; Chandrasekaran, M.

    2016-11-01

    The Electrical Spark Eroding Machining is an entrenched sophisticated machining process for producing complex geometry with close tolerances in hard materials like super alloy which are extremely difficult-to-machine by using conventional machining processes. It is sometimes offered as a better alternative or sometimes as an only alternative for generating accurate 3D complex shapes of macro, micro and nano-features in such difficult-to-machine materials among other advanced machining processes. The accomplishment of such challenging task by use of Electrical Spark Eroding Machining or Electrical Discharge Machining (EDM) is depending upon selection of apt process parameters. This paper is about analyzing the influencing of parameter in electrical eroding machining for Inconel 800 with electrolytic copper as a tool. The experimental runs were performed with various input conditions to process Inconel 800 nickel based super alloy for analyzing the response of material removal rate, surface roughness and tool wear rate. These are the measures of performance of individual experimental value of parameters such as pulse on time, Pulse off time, peak current. Taguchi full factorial Design by using Minitab release 14 software was employed to meet the manufacture requirements of preparing process parameter selection card for Inconel 800 jobs. The individual parameter's contribution towards surface roughness was observed from 13.68% to 64.66%.

  4. On the Optimal Selection of Electrical Machines Fans

    Directory of Open Access Journals (Sweden)

    Mădălin Costin

    2014-09-01

    Full Text Available In this paper an analytic relationship for electrical machine fan design has been developed. In the particularly case of salient poles synchronous machine (with salient poles – for electromagnetic field excitation or surface mounded permanent magnet, this approach allowed to express the fan power as a function of machine middle axe air gap. This analytic foundation developed may leads to different optimization criteria as specific active materials or costs. Numerical simulations confirm our approach.

  5. Optical alignment of electrodes on electrical discharge machines

    Science.gov (United States)

    Boissevain, A. G.; Nelson, B. W.

    1972-01-01

    Shadowgraph system projects magnified image on screen so that alignment of small electrodes mounted on electrical discharge machines can be corrected and verified. Technique may be adapted to other machine tool equipment where physical contact cannot be made during inspection and access to tool limits conventional runout checking procedures.

  6. General Relativity in Electrical Engineering

    OpenAIRE

    Leonhardt, Ulf; Philbin, Thomas G.

    2006-01-01

    In electrical engineering metamaterials have been developed that offer unprecedented control over electromagnetic fields. Here we show that general relativity lends the theoretical tools for designing devices made of such versatile materials. Given a desired device function, the theory describes the electromagnetic properties that turn this function into fact. We consider media that facilitate space-time transformations and include negative refraction. Our theory unifies the concepts operatin...

  7. Model of Pulsed Electrical Discharge Machining (EDM using RL Circuit

    Directory of Open Access Journals (Sweden)

    Ade Erawan Bin Minhat

    2014-10-01

    Full Text Available This article presents a model of pulsed Electrical Discharge Machining (EDM using RL circuit. There are several mathematical models have been successfully developed based on the initial, ignition and discharge phase of current and voltage gap. According to these models, the circuit schematic of transistor pulse power generator has been designed using electrical model in Matlab Simulink software to identify the profile of voltage and current during machining process. Then, the simulation results are compared with the experimental results.

  8. Unipolar Electric Machines with Liquid-Metal Current Pickup,

    Science.gov (United States)

    1984-03-08

    A new homopolar motor , e4ournal of the Franklin Institute*. 1954, v. 258, Ne 1. %4 144093, Bjo.1.leTeJb H3o6peTeHxA. 1962,. 14 1. 30. X oao p o a...VIII. Motor Mode of Unipolar Electrical Machine ............... 301 Chapter IX. Bases of Theory and Calculation of Nonpolar Dynamos without...unipolar electric motors . Are examined questions of the classification of acyclic machines, their electromagnetic field, calculation of magnetic circuit

  9. Development of Rotary Axis For Wire Electrical Discharge Machining (WEDM

    Directory of Open Access Journals (Sweden)

    M. Parthiban, C. Manigandan, G. Muthu Venkadesh, M. Ranjith Kumar

    2013-08-01

    Full Text Available This paper gives an overview of setting up a rotary axis to the existing WEDM machine to investigate the machining parameters in WEDG of harder materials. There are a number of hybrid machining processes (HMPs seeking the combined advantage of EDM and other machining techniques. One such combination is wire electrical discharge grinding (WEDG, which is commonly used for micro-machining of fine and hard rods. WEDG employs a single wire guide to confine the wire tension within the discharge area between the rod and the front edge of the wire and also to minimize the wire vibration. Other advantages of WEDG include the ability to machine hard- to- machine materials with large aspect ratio.

  10. Vibration Prediction Method of Electric Machines by using Experimental Transfer Function and Magnetostatic Finite Element Analysis

    Science.gov (United States)

    Saito, A.; Kuroishi, M.; Nakai, H.

    2016-09-01

    This paper concerns the noise and structural vibration caused by rotating electric machines. Special attention is given to the magnetic-force induced vibration response of interior-permanent magnet machines. In general, to accurately predict and control the vibration response caused by the electric machines, it is inevitable to model not only the magnetic force induced by the fluctuation of magnetic fields, but also the structural dynamic characteristics of the electric machines and surrounding structural components. However, due to complicated boundary conditions and material properties of the components, such as laminated magnetic cores and varnished windings, it has been a challenge to compute accurate vibration response caused by the electric machines even after their physical models are available. In this paper, we propose a highly-accurate vibration prediction method that couples experimentally-obtained discrete structural transfer functions and numerically-obtained distributed magnetic-forces. The proposed vibration synthesis methodology has been applied to predict vibration responses of an interior permanent magnet machine. The results show that the predicted vibration response of the electric machine agrees very well with the measured vibration response for several load conditions, for wide frequency ranges.

  11. Characterization of electrical properties of resistance welding machines

    Institute of Scientific and Technical Information of China (English)

    Wu Pei; Shao Yingli; Wenqi Zhang; Niels Bay

    2008-01-01

    Due to the individual electrical and mechanical characteristics of resistance welding machines, choice of the right machine and welding parameters for an optimized production is often difficult. This is especially the case in projection welding of complex joints. In this paper, a new approach of characterizing the electrical properties of AC resistance welding machines is presented, involving testing and mathematical modelling of the weld current, the firing angle and the conduction angle of silicon controlled rectifiers with the aid of a series of proof resistances. The model predicts the weld current and the conduction angle (or heat setting) at each set current, when the workpiece resistance is given.

  12. Machining Complex Oriented Compensation System for Generalized Kinematic Errors

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This paper puts forward a machining complex oriented compensation strategy for the generalized kinematic errors (GKEs).According to this strategy, the error map, which is constructed by using the off-line measuring information of the machined workpiece, is not oriented for the machine tool but for the machining complex to compensate the GKEs. The error map is derived by the proposed predictive learning control algorithm (PLCA), which is supported by the information model of machining complex. Experimental results show that the machining complex oriented GKEs compensation strategy and the information model based PLCA is effective.

  13. Converter applications and their influence on large electrical machines

    CERN Document Server

    Drubel, Oliver

    2013-01-01

    Converter driven applications are applied in more and more processes. Almost any installed wind-farm, ship drives, steel mills, several boiler feed water pumps, extruder and many other applications operate much more efficient and economic in case of variable speed solutions. The boundary conditions for a motor or generator will change, if it is supplied by a converter. An electrical machine, which is operated by a converter, can no longer be regarded as an independent component, but is embedded in a system consisting of converter and machine. This book gives an overview of existing converter designs for large electrical machines. Methods for the appropriate calculation of machine phenomena, which are implied by converters are derived in the power range above 500kVA. It is shown how due to the converter inherent higher voltage harmonics and pulse frequencies special phenomena are caused inside the machine which can be the reason for malfunction. It is demonstrated that additional losses create additional tempe...

  14. Standard of Electrical Washing Machine for Household and Similar Purposes

    Institute of Scientific and Technical Information of China (English)

    Lu Jianguo

    2011-01-01

    Background With further improvement of people's living,the household washing machine industry has entered a new stage of development.However,some indicators of GB/T 4288-2003 have become no longer suitable for the development of household washing machine products at present.Particularly,with an increasing number of basic functions and auxiliary functions,many aspects are not covered by the existing standard.In order to further improve the overall quality of China's household washing machines and enhance their competitiveness in the international market,guide manufacturers to produce household washing machines in line with the demands of consumers and instruct consumers to properly purchase and use household washing machines,it is imperative to revise the GB/T 4288-2003 Household Electric Washing Machine.

  15. A Review on the Faults of Electric Machines Used in Electric Ships

    Directory of Open Access Journals (Sweden)

    Dionysios V. Spyropoulos

    2013-01-01

    Full Text Available Electric propulsion systems are today widely applied in modern ships, including transport ships and warships. The ship of the future will be fully electric, and not only its propulsion system but also all the other services will depend on electric power. The robust and reliable operation of the ship’s power system is essential. In this work, a review on the mechanical and electrical faults of electric machines that are used in electric ships is presented.

  16. Dynamic study of synchronous machine electric drive

    Directory of Open Access Journals (Sweden)

    Dimitar Spirov

    2005-10-01

    Full Text Available The dynamic behaviour of the fan blower synchoronous machine drive have been studied in the paper. The equations for the voltages of the synchoronous machine windings are presented in a coordinate system which rotates at the angular speed of the rotor. The mechanical equipment is presented by means of a single-mass dynamic model. The derived system of differential equations is transformed and solved using suitable software product. The results obtained for rotation frequency and electromagnetic torque motor in the courses of different values of rated supply voltage and of different initial resistant moment of the mechanism have been graphically presented. Conclusions from the results obtained have been done.

  17. Development of an Electrically Operated Cassava Peeling and Slicing Machine

    Directory of Open Access Journals (Sweden)

    I. S. Aji

    2017-08-01

    Full Text Available The development and construction of an electrically operated cassava peeling and slicing machine was described in this paper. The objective was to design, construct and test an electrically operated machine that will peel and slice cassava root into chips, to aid the processes of drying, pelletizing and storage. The methodology adopted includes; design, construction, calculation, specification, assembly of component parts and performance test. The machine was able to Peel and slice cassava to fairly similar sizes. Performance test reveals that 7 kg of cassava tuber was peeled and chipped in one minute, which shows that, the machine developed can significantly reduce the cost of labour and time wastage associated with traditional processing of cassava tubers into dried cassava pellets, and finished products, such as; garri, and cassava flour. The machine has a capacity of 6.72 kg/min, with peeling and chipping efficiency of 66.2% and 84.0% respectively. The flesh loss of the peeled tuber was 8.52%, while overall machine efficiency obtained as 82.4%. The machine is recommended for use by small scale industries and by cassava farmers in the rural areas. It has an overall cost of N46100 ($150. The machine can easily be operated by an individual and maintained, by using warm water to wash the component parts, and sharpening of the chipping disc when required.

  18. Operating point resolved loss computation in electrical machines

    Directory of Open Access Journals (Sweden)

    Pfingsten Georg Von

    2016-03-01

    Full Text Available Magnetic circuits of electromagnetic energy converters, such as electrical machines, are nowadays highly utilized. This proposition is intrinsic for the magnetic as well as the electric circuit and depicts that significant enhancements of electrical machines are difficult to achieve in the absence of a detailed understanding of underlying effects. In order to improve the properties of electrical machines the accurate determination of the locally distributed iron losses based on idealized model assumptions solely is not sufficient. Other loss generating effects have to be considered and the possibility being able to distinguish between the causes of particular loss components is indispensable. Parasitic loss mechanisms additionally contributing to the total losses originating from field harmonics, non-linear material behaviour, rotational magnetizations, and detrimental effects caused by the manufacturing process or temperature, are not explicitly considered in the common iron-loss models, probably even not specifically contained in commonly used calibration factors. This paper presents a methodology being able to distinguish between different loss mechanisms and enables to individually consider particular loss mechanisms in the model of the electric machine. A sensitivity analysis of the model parameters can be performed to obtain information about which decisive loss origin for which working point has to be manipulated by the electromagnetic design or the control of the machine.

  19. Electrical discharge machining studies on reactive sintered FeAl

    Indian Academy of Sciences (India)

    A K Khanra; S Patra; M M Godkhindi

    2006-06-01

    Electrical discharge machining (EDM) studies on reactive sintered FeAl were carried out with different process parameters. The metal removal rate and tool removal rate were found to increase with the applied pulse on-time. The surface roughness of machined surface also changed with the applied pulse on-time. XRD analysis of machined surface of sintered FeAl showed the formation of Fe3C phase during the EDM process. The debris analysis was used to identify the material removal mechanism occurring during the EDM of sintered FeAl.

  20. Characterization of nanoparticles from abrasive waterjet machining and electrical discharge machining processes.

    Science.gov (United States)

    Ling, Tsz Yan; Pui, David Y H

    2013-11-19

    Abrasive Waterjet Machining (AWM) and Electrical Discharge Machining (EDM) processes are found to produce nanoparticles during operation. Impacts of engineered nanoparticles released to the environment and biological system have caused much concern. Similarly, the nanoparticles unintentionally produced by the AWM and EDM can lead to comparable effects. By application of the Nanoparticle Tracking Analysis (NTA) technique, the size distribution and concentration of nanoparticles in the water used in AWM and EDM were measured. The particles generally have a peak size of 100-200 nm. The filtration systems of the AWM and EDM processes were found to remove 70% and 90% the nanoparticles present, respectively. However, the particle concentration of the filtered water from the AWM was still four times higher than that found in regular tap water. These nanoparticles are mostly agglomerated, according to the microscopy analysis. Using the electron dispersive spectroscopy (EDS) technique, the particles are confirmed to come from the debris of the materials cut with the equipment. Since AWM and EDM are widely used, the handling and disposal of used filters collected with nanoparticles, release of nanoparticles to the sewer, and potential use of higher performance filters for these processes will deserve further consideration.

  1. Regulation of unbalanced electromagnetic moment in mutual loading systems of electric machines of traction rolling stock and multiple unit of mainline and industrial transport

    Directory of Open Access Journals (Sweden)

    A. M. Afanasov

    2014-12-01

    Full Text Available Purpose. The research data are aimed to identify the regulatory principles of unbalanced electromagnetic moment of mutually loaded electric machines of traction rolling stock and multiple unit of main and industrial transport. The purpose of this study is energy efficiency increase of the testing of traction electric machines of direct and pulse current using the improvement methods of their mutual loading, including the principles of automatic regulation of mutual loading system. Methodology. The general theoretical provisions and principles of system approach to the theoretical electric engineering, the theory of electric machines and theoretical mechanics are the methodological basis of this research. The known methods of analysis of electromagnetic and electromechanical processes in electrical machines of direct and pulse current are used in the study. Methods analysis of loading modes regulation of traction electric machines was conducted using the generalized scheme of mutual loading. It is universal for all known methods to cover the losses of idling using the electric power. Findings. The general management principles of mutual loading modes of the traction electric machines of direct and pulse current by regulating their unbalanced electric magnetic moment were developed. Regulatory options of unbalanced electromagnetic moment are examined by changing the difference of the magnetic fluxes of mutually loaded electric machines, the current difference of electric machines anchors, the difference of the angular velocities of electric machines shafts. Originality. It was obtained the scientific basis development to improve the energy efficiency test methods of traction electric machines of direct and pulse current. The management principles of mutual loading modes of traction electric machines were formulated. For the first time it is introduced the concept and developed the principles of regulation of unbalanced electromagnetic moment in

  2. Development of CAD/CAM System for Cross Section’s Changing Hole Electrical Discharge Machining

    Science.gov (United States)

    Ishida, Tohru; Ishiguro, Eiki; Kita, Masahiko; Nakamoto, Keiichi; Takeuchi, Yoshimi

    This study deals with the development of a new CAD/CAM system for fabricating holes whose cross sections change variously. The cross sections of machined holes are generally constant. The limitations in the shapes of holes that can be machined make obstacles in the design stage of industrial products. A new device that utilizes electrical discharge machining has been developed that can create holes with various cross sections to solve this problem. However, it has been impossible to put the device into practical use since there has been no software that has enabled the designed shapes to be easily machined. Therefore, we aimed at developing a new CAD/CAM system for machining the beforehand designed holes with changing cross sections by using the device. As the first step in developing the CAD/CAM system, the post processor in the CAM system is formulated in this paper.

  3. Passivity-based control of a class of Blondel-Park transformable electric machines

    Energy Technology Data Exchange (ETDEWEB)

    Nicklasson, Per J.; Ortega, Romeo; Espinosa-Perez, Gerardo

    1997-12-31

    The publication presents a study of the viability of extending, to the general rotating electric machine`s model, the passivity-based controller method developed for induction motors. In this approach, the passivity (energy dissipation) properties of the motor are taken advantage of at two different levels. First, there is proved that the motor model can be decomposed as the feedback interconnection of two passive subsystems, which can essentially be identified with the electrical and mechanical dynamics. Then, a torque tracking controller is designed that preserves passivity for the electrical subsystem, and leave the mechanical part as a ``passive disturbance``. In position or speed control applications this procedure naturally leads to the well known cascaded controller structure which is typically analyzed invoking time-scale separation assumptions. A key future of the new cascaded control paradigm is that the latter arguments are obviated in the stability analysis. The objective in this publication is to characterize a class of machines for which such a passivity-based controller solves the output feedback torque tracking problem. Roughly, the class consists of machines whose non-actuated dynamics are well damped and whose electrical and mechanical dynamics can be suitably decoupled via a coordinate transformation. The first condition translates into the requirement of approximate knowledge of the rotor resistances to avoid the need of injecting high gain into the loop. The latter condition is known in the electric machines literature as Blonded-Park transformability, and in practical terms it requires that the air-gap magnetomotive force must be suitably approximated by the first harmonic in its Fourier expansion. These conditions have a clear physical interpretation in terms of the couplings between its electrical, magnetic and mechanical dynamics, and are satisfied by a large number of practical machines. The controller mentioned reduces to the well known

  4. Direct digital simulation of power semiconductor-controlled electrical machines

    Science.gov (United States)

    Bahnassy, H. M.

    1981-06-01

    Generalized computer programming techniques for simulating power semiconductor-controlled electric machines in coil-variable representation are presented. These techniques are developed primarily for implementation in large scale general purpose computer-aided design and analysis (CADA) circuit programs. To demonstrate the validity of the developed techniques, a coil-variable model of a brushless synchronous generator with an ac exciter and rotating rectifiers was constructed. The performance of the control system (thyristor voltage regulator) is represented by a transfer function block diagram model. The CADA circuit program used is the recently developed SUPER SCEPTRE program. The model is validated using the design data and test results of a 60 kVA brushless generator. Numerous computer simulation cases are presented including the steady state and transient conditions. Brushless generator performance under diode failure faults (opened-diode, shorted-diode) is simulated. The effects of the external faults, at the main generator terminals, on the main generator, as well as its excitation system currents, are simulated.

  5. Design of electric control system for automatic vegetable bundling machine

    Science.gov (United States)

    Bao, Yan

    2017-06-01

    A design can meet the requirements of automatic bale food structure and has the advantages of simple circuit, and the volume is easy to enhance the electric control system of machine carrying bunch of dishes and low cost. The bundle of vegetable machine should meet the sensor to detect and control, in order to meet the control requirements; binding force can be adjusted by the button to achieve; strapping speed also can be adjusted, by the keys to set; sensors and mechanical line connection, convenient operation; can be directly connected with the plug, the 220V power supply can be connected to a power source; if, can work, by the transmission signal sensor, MCU to control the motor, drive and control procedures for small motor. The working principle of LED control circuit and temperature control circuit is described. The design of electric control system of automatic dish machine.

  6. Clean Electrical-Discharge Machining Of Delicate Honeycomb

    Science.gov (United States)

    Johnson, Clarence S.

    1993-01-01

    Precise recesses in fragile metal honeycomb blocks formed in special electrical-discharge machining process. Special tooling used, and recesses bored with workpiece in nonstandard alignment. Cutting electrode advances into workpiece along x axis to form pocket of rectangular cross section. Deionized water flows from fitting, along honeycomb tubes of workpiece, to electrode/workpiece interface.

  7. Refining cast implant-retained restorations by electrical discharge machining.

    Science.gov (United States)

    Schmitt, S M; Chance, D A; Cronin, R J

    1995-03-01

    The UCLA abutment was developed to create implant-retained restorations with ideal contours, excellent esthetics, and minimal vertical space requirements for restorative materials. A major drawback of this abutment is that casting inaccuracies in the lost-wax process are difficult to control. This article describes a method of refining cast implant-retained restorations by use of electrical discharge machining.

  8. [Algorithms, machine intelligence, big data : general considerations].

    Science.gov (United States)

    Radermacher, F J

    2015-08-01

    We are experiencing astonishing developments in the areas of big data and artificial intelligence. They follow a pattern that we have now been observing for decades: according to Moore's Law,the performance and efficiency in the area of elementary arithmetic operations increases a thousand-fold every 20 years. Although we have not achieved the status where in the singular sense machines have become as "intelligent" as people, machines are becoming increasingly better. The Internet of Things has again helped to massively increase the efficiency of machines. Big data and suitable analytics do the same. If we let these processes simply continue, our civilization may be endangerd in many instances. If the "containment" of these processes succeeds in the context of a reasonable political global governance, a worldwide eco-social market economy, andan economy of green and inclusive markets, many desirable developments that are advantageous for our future may result. Then, at some point in time, the constant need for more and faster innovation may even stop. However, this is anything but certain. We are facing huge challenges.

  9. Amorphous metals for radial airgap electric machines

    Energy Technology Data Exchange (ETDEWEB)

    Lu Ning; Kokernak, J.M. [Rensselaer Polytechnic Institute, Dept. of Electric Poer Engineering, Troy, NY (United States)

    2000-08-01

    Amorphous steel teas been in use for some time in the transformer industry. The difficulty associated with handling such a hard material paired with the extremely thin nature of the casting has prevented amorphous steel from being seriously considered for radial airgap electric motors. In light of recent advances in manufacturing and handling of the amorphous materials, this paper presents an investigation into the performance advantages of an amorphous brushless dc motor. A two-dimensional, time-stepped, finite element model is used to analyze the electromagnetic field and motor performance for an amorphous brushless dc (BLDC) motor and a M-l9 BLDC motor. Each is modeled with identical structure geometries. Magnetic core losses are also estimated for the two motors operating over a frequency range of 50 to 200 Hz. (orig.)

  10. Using of Expert Systems in Electrodiagnostics of Large Electrical Machines

    Directory of Open Access Journals (Sweden)

    K. Záliš

    2000-01-01

    Full Text Available Several rule-based expert systems were developed for diagnostics of high voltage (HV insulation systems, especially for the evaluation of partial discharge (PD activity. Several rule-based expert systems were developed in the cooperation of top diagnostic workplaces of the Czech Republic for this purpose. The IZOLEX expert system evaluates diagnostic measurement data from commonly used off-line diagnostic methods for the diagnostics of HV insulation of rotating machines, non-rotating machines and insulating oils. The CVEX expert system evaluates the PD activity on HV electrical machines and equipment by means of an off-line measurement. The CVEXON expert system is for the evaluation of the discharge activity by on-line measurement and the ALTONEX expert system is the system for on-line monitoring of rotating machines. The complex project for the evaluation of a PD measurement on HV insulation systems has also been made. This complex evaluating system includes two parallel expert systems for the evaluation of a PD activity on HV electrical machines.

  11. Parameter optimization model in electrical discharge machining process

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Electrical discharge machining (EDM) process, at present is still an experience process, wherein selected parameters are often far from the optimum, and at the same time selecting optimization parameters is costly and time consuming. In this paper,artificial neural network (ANN) and genetic algorithm (GA) are used together to establish the parameter optimization model. An ANN model which adapts Levenberg-Marquardt algorithm has been set up to represent the relationship between material removal rate (MRR) and input parameters, and GA is used to optimize parameters, so that optimization results are obtained. The model is shown to be effective, and MRR is improved using optimized machining parameters.

  12. Sample preparation of metal alloys by electric discharge machining

    Science.gov (United States)

    Chapman, G. B., II; Gordon, W. A.

    1976-01-01

    Electric discharge machining was investigated as a noncontaminating method of comminuting alloys for subsequent chemical analysis. Particulate dispersions in water were produced from bulk alloys at a rate of about 5 mg/min by using a commercially available machining instrument. The utility of this approach was demonstrated by results obtained when acidified dispersions were substituted for true acid solutions in an established spectrochemical method. The analysis results were not significantly different for the two sample forms. Particle size measurements and preliminary results from other spectrochemical methods which require direct aspiration of liquid into flame or plasma sources are reported.

  13. A NEW DESIGN of SIX- PHASE ROTARY CONVERTER ELECTRIC MACHINE

    Directory of Open Access Journals (Sweden)

    K. G. Mohammed

    2012-12-01

    Full Text Available The aim of this research is to design a new ac rotary converter machine to convert the ac single phase voltage to six-phase voltages by using multi stages energy conversion machine. The rotary converter is composed from two main stages and is combined into one frame. These two stages are formed from three main electromagnetic components. The first component represents the input stage that enables the energy from single phase to enter and transformed by the second and third components electro-magnetically to produce six-phase voltages which at the output stage. The programs are created using MATLAB in order to calculate the required dimensions of the converter machine and its parameters for magnetic and electrical circuits.

  14. Electric machines modeling, condition monitoring, and fault diagnosis

    CERN Document Server

    Toliyat, Hamid A; Choi, Seungdeog; Meshgin-Kelk, Homayoun

    2012-01-01

    With countless electric motors being used in daily life, in everything from transportation and medical treatment to military operation and communication, unexpected failures can lead to the loss of valuable human life or a costly standstill in industry. To prevent this, it is important to precisely detect or continuously monitor the working condition of a motor. Electric Machines: Modeling, Condition Monitoring, and Fault Diagnosis reviews diagnosis technologies and provides an application guide for readers who want to research, develop, and implement a more effective fault diagnosis and condi

  15. Microelectrode array fabrication by electrical discharge machining and chemical etching.

    Science.gov (United States)

    Fofonoff, Timothy A; Martel, Sylvain M; Hatsopoulos, Nicholas G; Donoghue, John P; Hunter, Ian W

    2004-06-01

    Wire electrical discharge machining (EDM), with a complementary chemical etching process, is explored and assessed as a method for developing microelectrode array assemblies for intracortically recording brain activity. Assembly processes based on these methods are highlighted, and results showing neural activity successfully recorded from the brain of a mouse using an EDM-based device are presented. Several structures relevant to the fabrication of microelectrode arrays are also offered in order to demonstrate the capabilities of EDM.

  16. INFLUENCE OF FEEDING ELECTRIC ENERGY QUALITY ON HEATING OF THE AUXILIARY MA-CHINES OF AC ELECTRIC ROLLING STOCK

    Directory of Open Access Journals (Sweden)

    O. YU. Baliichuk

    2014-04-01

    Full Text Available Purpose. The article aims to study the problem of increase the reliability of auxiliary machines for AC electric trains during operation in real conditions. Methodology. The peculiarity of system construction of auxiliary machines for AC electric rolling stock is the use of asynchronous motors for general industrial purpose. An engineering method of influence determination on the feeding voltage asymmetry and its deviation from the nominal value on heating of auxiliary machines insulation was proposed. Findings. It is found out that in case when the auxiliary machines of AC electric trains work under asymmetry factor of the voltage 10% or more and feeding voltage deviation from the nominal order 0.6 relative unit then it is possible the overheat of their isolation, even if it has class H. Originality. For the first time the issue of the total insulation heating under such boundary parameters combinations of energy quality, when each of them contributes to the heating insulation increase as compared to the nominal regime of the "rotating phase splitter−auxiliary machinery" system was illuminated. Practical value. Conducted research allow us to establish the boundary parameter values of feeding energy quality (asymmetry factor, feeding voltage deviations from the nominal value, at which additional isolation overheating of this class under the effect of specified factors will not exceed the agreed value.

  17. Recent Educational Experiences in Electric Machine Maintenance Teaching

    Directory of Open Access Journals (Sweden)

    Jose Alfonso Antonino-Daviu

    2013-05-01

    Full Text Available Maintenance of electric machines and installations is a particularly important area; eventual faults in these devices may lead to significant losses in terms of time and money. The investment and concern in developing proper maintenance protocols have been gradually increasing over recent decades. As a consequence, there is a need to instruct future engineers in the electric machines and installations maintenance area. The subject "Maintenance of Electric Machines and Installations" has been designed under this idea. It is taught within an official master degree in Maintenance Engineering. This work describes the educational experiences reached during the initial years of the teaching of the subject. Aspects such as student profiles, subject approaches, design of the syllabus, methodology and structure of the laboratory sessions are remarked in the work. In addition, the paper discusses other educational strategies which are being introduced to increase the interest in the subject, such as integration of Information and Communication Technologies (ICT, promotion of the collaborative work, inclusion of the possibility of remote learning or development of new assessment systems.

  18. Passivity-based control of a Class of Blondel-Park transformable electric machines

    Energy Technology Data Exchange (ETDEWEB)

    Nicklasson, Per Johan; Ortega, Romeo; Espinosa-Perez, Gerardo

    1997-07-01

    The publication relates to a study of the viability of extending, to the general rotating electric machine model, the passivity-based controller method being developed for induction motors. In this approach the passivity (energy dissipation) properties of the motor are taken advantage of at two different levels. First, there is proved that the motor model can be decomposed as the feedback interconnection of two passive subsystems, which essentially be identified with the electrical and mechanical dynamics. Secondly, there is designed a torque-tracking controller that preserves passivity for the electrical subsystem and leaves the mechanical part as a ``passive disturbance``. The objective of this publication is to characterize a class of machines for which such a passivity-based controller solves the output feedback torque-tracking problem. 75 refs., 7 figs., 1 tab.

  19. Guest Editorial Electric Machines in Renewable Energy Applications

    Energy Technology Data Exchange (ETDEWEB)

    Aliprantis, Dionysios; El-Sharkawi, Mohamed; Muljadi, Eduard; Brown, Ian; Chiba, Akira; Dorrell, David; Erlich, Istvan; Kerszenbaum, Isidor Izzy; Levi, Emil; Mayor, Kevin; Mohammed, Osama; Papathanassiou, Stavros; Popescu, Mircea; Qiao, Wei; Wu, Dezheng

    2015-12-01

    The main objective of this special issue is to collect and disseminate publications that highlight recent advances and breakthroughs in the area of renewable energy resources. The use of these resources for production of electricity is increasing rapidly worldwide. As of 2015, a majority of countries have set renewable electricity targets in the 10%-40% range to be achieved by 2020-2030, with a few notable exceptions aiming for 100% generation by renewables. We are experiencing a truly unprecedented transition away from fossil fuels, driven by environmental, energy security, and socio-economic factors.Electric machines can be found in a wide range of renewable energy applications, such as wind turbines, hydropower and hydrokinetic systems, flywheel energy storage devices, and low-power energy harvesting systems. Hence, the design of reliable, efficient, cost-effective, and controllable electric machines is crucial in enabling even higher penetrations of renewable energy systems in the smart grid of the future. In addition, power electronic converter design and control is critical, as they provide essential controllability, flexibility, grid interface, and integration functions.

  20. Passivity-Based Control of a Class of Blondel-Park Transformable Electric Machines

    Directory of Open Access Journals (Sweden)

    Per J. Nicklasson

    1997-10-01

    Full Text Available In this paper we study the viability of extending, to the general rotating electric machine's model, the passivity-based controller method that we have developed for induction motors. In this approach the passivity (energy dissipation properties of the motor are taken advantage of at two different levels. First, we prove that the motor model can be decomposed as the feedback interconnection of two passive subsystems, which can essentially be identified with the electrical and mechanical dynamics. Then, we design a torque tracking controller that preserves passivity for the electrical subsystem, and leave the mechanical part as a "passive disturbance". In position or speed control applications this procedure naturally leads to the well known cascaded controller structure which is typically analyzed invoking time-scale separation assumptions. A key feature of the new cascaded control paradigm is that the latter arguments are obviated in the stability analysis. Our objective in this paper is to characterize a class of machines for which such a passivity-based controller solves the output feedback torque tracking problem. Roughly speaking, the class consists of machines whose nonactuated dynamics are well damped and whose electrical and mechanical dynamics can be suitably decoupled via a coordinate transformation. The first condition translates into the requirement of approximate knowledge of the rotor resistances to avoid the need of injecting high gain into the loop. The latter condition is known in the electric machines literature as Blondel-Park transformability, and in practical terms it requires that the air-gap magnetomotive force must be suitably approximated by the first harmonic in its Fourier expansion. These conditions, stemming from the construction of the machine, have a clear physical interpretation in terms of the couplings between its electrical, magnetic and mechanical dynamics, and are satisfied by a large number of practical

  1. A new MSc course on diagnostics of electrical machines and power electronics

    DEFF Research Database (Denmark)

    Leban, Krisztina Monika; Ritchie, Ewen

    2011-01-01

    This paper presents the structure, methodology and content of a new Diagnostics course at the Department of Energy Engineering, AAU. The lectures were to suit the problem based learning teaching method practised at AAU. Teaching was oriented to support the semester projects of the participating...... students. Additionally, specific subjects requested by participants, basic diagnosis and testing methods were presented during the lectures and workshops. General engineering knowledge about electric machines, power electronics and the combination of these was presented. The laboratory method, experiments...

  2. Enhanced osteoblast response to electrical discharge machining surface.

    Science.gov (United States)

    Otsuka, Fukunaga; Kataoka, Yu; Miyazaki, Takashi

    2012-01-01

    The purpose of this study is to investigate the surface characteristics and biocompatibility of titanium (Ti) surfaces modified by wire electrical discharge machining (EDM). EDM surface characteristics were evaluated by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), thin-film X-ray diffractometry (XRD) and contact angle measurements. MC3T3-E1 cell morphology, attachment and proliferation, as well as analysis of osteoblastic gene expressions, on machined surfaces and EDM surfaces were also evaluated. EDM surfaces exhibited high super hydrophilicity, due to high surface energy. XPS and XRD revealed that a passive oxide layer with certain developing thickness onto. EDM surfaces promoted cell attachment, but restrained proliferation. Counted cell numbers increased significantly on the machined surfaces as compared to the EDM surfaces. Real-time PCR analyses showed significantly higher relative mRNA expression levels of osteoblastic genes (ALP, osteocalcin, Runx2, Osterix) in cells cultured on the EDM surfaces as compared to cells cultured on the machined surfaces.

  3. Application brushless machines with combine excitation for a hybrid car and an electric car

    OpenAIRE

    Gandzha S.A.; Kiessh I.E.

    2015-01-01

    This article shows advantages of application the brushless machines with combined excitation (excitation from permanent magnets and excitation winding) for the hybrid car and the electric car. This type of electric machine is compared with a typical brushless motor and an induction motor. The main advantage is the decrease of the dimensions of electric machine and the reduction of the price for an electronic control system. It is shown the design and the principle of operation of the electric...

  4. Application brushless machines with combine excitation for a hybrid car and an electric car

    Directory of Open Access Journals (Sweden)

    Gandzha S.A.

    2015-08-01

    Full Text Available This article shows advantages of application the brushless machines with combined excitation (excitation from permanent magnets and excitation winding for the hybrid car and the electric car. This type of electric machine is compared with a typical brushless motor and an induction motor. The main advantage is the decrease of the dimensions of electric machine and the reduction of the price for an electronic control system. It is shown the design and the principle of operation of the electric machine. The machine was modeled using Solidworks program for creating design and Maxwell program for the magnetic field analysis. The result of tests is shown as well.

  5. Electrical test prediction using hybrid metrology and machine learning

    Science.gov (United States)

    Breton, Mary; Chao, Robin; Muthinti, Gangadhara Raja; de la Peña, Abraham A.; Simon, Jacques; Cepler, Aron J.; Sendelbach, Matthew; Gaudiello, John; Emans, Susan; Shifrin, Michael; Etzioni, Yoav; Urenski, Ronen; Lee, Wei Ti

    2017-03-01

    Electrical test measurement in the back-end of line (BEOL) is crucial for wafer and die sorting as well as comparing intended process splits. Any in-line, nondestructive technique in the process flow to accurately predict these measurements can significantly improve mean-time-to-detect (MTTD) of defects and improve cycle times for yield and process learning. Measuring after BEOL metallization is commonly done for process control and learning, particularly with scatterometry (also called OCD (Optical Critical Dimension)), which can solve for multiple profile parameters such as metal line height or sidewall angle and does so within patterned regions. This gives scatterometry an advantage over inline microscopy-based techniques, which provide top-down information, since such techniques can be insensitive to sidewall variations hidden under the metal fill of the trench. But when faced with correlation to electrical test measurements that are specific to the BEOL processing, both techniques face the additional challenge of sampling. Microscopy-based techniques are sampling-limited by their small probe size, while scatterometry is traditionally limited (for microprocessors) to scribe targets that mimic device ground rules but are not necessarily designed to be electrically testable. A solution to this sampling challenge lies in a fast reference-based machine learning capability that allows for OCD measurement directly of the electrically-testable structures, even when they are not OCD-compatible. By incorporating such direct OCD measurements, correlation to, and therefore prediction of, resistance of BEOL electrical test structures is significantly improved. Improvements in prediction capability for multiple types of in-die electrically-testable device structures is demonstrated. To further improve the quality of the prediction of the electrical resistance measurements, hybrid metrology using the OCD measurements as well as X-ray metrology (XRF) is used. Hybrid metrology

  6. Static Measurements on HTS Coils of Fully Superconducting AC Electric Machines for Aircraft Electric Propulsion System

    Science.gov (United States)

    Choi, Benjamin B.; Hunker, Keith R.; Hartwig, Jason; Brown, Gerald V.

    2017-01-01

    The NASA Glenn Research Center (GRC) has been developing the high efficiency and high-power density superconducting (SC) electric machines in full support of electrified aircraft propulsion (EAP) systems for a future electric aircraft. A SC coil test rig has been designed and built to perform static and AC measurements on BSCCO, (RE)BCO, and YBCO high temperature superconducting (HTS) wire and coils at liquid nitrogen (LN2) temperature. In this paper, DC measurements on five SC coil configurations of various geometry in zero external magnetic field are measured to develop good measurement technique and to determine the critical current (Ic) and the sharpness (n value) of the super-to-normal transition. Also, standard procedures for coil design, fabrication, coil mounting, micro-volt measurement, cryogenic testing, current control, and data acquisition technique were established. Experimentally measured critical currents are compared with theoretical predicted values based on an electric-field criterion (Ec). Data here are essential to quantify the SC electric machine operation limits where the SC begins to exhibit non-zero resistance. All test data will be utilized to assess the feasibility of using HTS coils for the fully superconducting AC electric machine development for an aircraft electric propulsion system.

  7. SHARK a new concept in electrical machines. Closing report

    Energy Technology Data Exchange (ETDEWEB)

    Ritchie, E.; Omand Rasmussen, P.; Tataru Kjaer, A,M.

    2004-10-01

    The research is rooted in the effort to reduce the energy consumed by electric motors. This work explored the idea that the efficiency of a specific type of electric motor may be improved by replacing the usual cylindrical air gap by a non-linear air gap. This idea is not new, other reports addressing this subject having been published prior to this work. However, no systematic analysis has been reported previously. Previous publications tried to demonstrate that the concept could function. The commercial applicability of this concept, called SHARK, was not considered seriously, because of the assembly difficulties caused by the non-linear air gap. However, these problems may be overcome by recently reported technologies. Thus a detailed analysis of the effect of the SHARK air gap on the performance of electric motors became more interesting. The methodology of the study was aimed to provide an analysis tool for future SHARK air gap machines. A Switched Reluctance Machines was selected as vehicle for this study, due to its simple geometry. The study regarded the linear analysis and the Finite Element Analysis as the main tools capable of providing basic knowledge of the magnetic behaviour of various air gap shapes applied in SRM. Based on results obtained from these, an analytical model, describing the magnetisation characteristics of the SHARK SRM in the aligned and unaligned rotor positions, was proposed. The modelling principle was to adapt an existing model of the cylindrical air gap SRM to account for the influence of the SHARK profile in the air gap. The proposed model was used to generate families of characteristics showing the relative improvement in terms of converted energy of the SHARK SRM in comparison with a cylindrical air gap SRM having identical main dimensions. Calculations were verified by measurements on two machines having cylindrical and saw-toothed air gaps. In addition, the performance of an Induction Motor and a brushless DC motor were

  8. Technical and economic aspects of electric machine industry development with account of electric power development directions

    Directory of Open Access Journals (Sweden)

    V.V. Shevchenko

    2014-04-01

    Full Text Available A critical assessment of the existing views on the world energy development prospects is an integral part of independent policy elaboration in this field for any state. Consideration of prospective power industry development options is a determinative factor in electric machine-building progress as a generation system production industry.

  9. GenSVM: a generalized multiclass support vector machine

    NARCIS (Netherlands)

    G.J.J. van den Burg (Gerrit); P.J.F. Groenen (Patrick)

    2016-01-01

    textabstractTraditional extensions of the binary support vector machine (SVM) to multiclass problems are either heuristics or require solving a large dual optimization problem. Here, a generalized multiclass SVM is proposed called GenSVM. In this method classification boundaries for a K-class proble

  10. Engineering electrodynamics electric machine, transformer, and power equipment design

    CERN Document Server

    Turowski, Janusz

    2013-01-01

    Due to a huge concentration of electromagnetic fields and eddy currents, large power equipment and systems are prone to crushing forces, overheating, and overloading. Luckily, power failures due to disturbances like these can be predicted and/or prevented.Based on the success of internationally acclaimed computer programs, such as the authors' own RNM-3D, Engineering Electrodynamics: Electric Machine, Transformer, and Power Equipment Design explains how to implement industry-proven modeling and design techniques to solve complex electromagnetic phenomena. Considering recent progress in magneti

  11. Power quality in power systems and electrical machines

    CERN Document Server

    Fuchs, Ewald

    2015-01-01

    The second edition of this must-have reference covers power quality issues in four parts, including new discussions related to renewable energy systems. The first part of the book provides background on causes, effects, standards, and measurements of power quality and harmonics. Once the basics are established the authors move on to harmonic modeling of power systems, including components and apparatus (electric machines). The final part of the book is devoted to power quality mitigation approaches and devices, and the fourth part extends the analysis to power quality solutions for renewable

  12. Two phase gap cooling of an electrical machine

    Energy Technology Data Exchange (ETDEWEB)

    Shoykhet, Boris A.

    2016-10-04

    An electro-dynamic machine has a rotor and stator with a gap therebetween. The machine has a frame defining a hollow interior with end cavities on axially opposite ends of the frame. A gas circulating system has an inlet that supplies high pressure gas to the frame interior and an outlet to collect gas passing therethrough. A liquid coolant circulating system has an inlet that supplies coolant to the frame interior and an outlet that collects coolant passing therethrough. The coolant inlet and gas inlet are generally located on the frame in a manner to allow coolant from the coolant inlet to flow with gas from the gas inlet to the gap. The coolant outlet and gas outlet are generally located on the frame in a manner to allow the coolant to be separated from the gas with the separated coolant and gas collected for circulation through their respective circulating systems.

  13. Two phase gap cooling of an electrical machine

    Science.gov (United States)

    Shoykhet, Boris A.

    2016-10-04

    An electro-dynamic machine has a rotor and stator with a gap therebetween. The machine has a frame defining a hollow interior with end cavities on axially opposite ends of the frame. A gas circulating system has an inlet that supplies high pressure gas to the frame interior and an outlet to collect gas passing therethrough. A liquid coolant circulating system has an inlet that supplies coolant to the frame interior and an outlet that collects coolant passing therethrough. The coolant inlet and gas inlet are generally located on the frame in a manner to allow coolant from the coolant inlet to flow with gas from the gas inlet to the gap. The coolant outlet and gas outlet are generally located on the frame in a manner to allow the coolant to be separated from the gas with the separated coolant and gas collected for circulation through their respective circulating systems.

  14. Developmental condition and technical problems on electric insulation for super-conducting electric power machine

    Science.gov (United States)

    Motoyama, H.

    1989-05-01

    The present situations of superconducting electric power machines in the world and studied problems were investigated from viewpoint of the electric insulation. 50MVA generator (CRIE/Hitachi) or 120MVA generator (KWU/Siemens) where the dc superconducting technique was applied on field windings, are developed. As to Superconducting transformer, 220KVA transformer is trially manufactured and the conceptual design of 1,000MVA transformer is made by W.H. or Alstom. Future problems are the study of protecting method for the overvoltage to superconducting electric power machines and the study to prevent the quench for superconducting windings. The respective insulating characteristics of solid and liquid insulators become clear gradually under the cryogenic condition but a large part of insulating characteristics of composite insulator prepared by combination of both insulators are not clear, so that these problems must be clarified.

  15. Electrical machines and assemblies including a yokeless stator with modular lamination stacks

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Ronghai; Jansen, Patrick Lee; Bagepalli, Bharat Sampathkumar; Carl, Jr., Ralph James; Gadre, Aniruddha Dattatraya; Lopez, Fulton Jose

    2010-04-06

    An electrical machine includes a rotor with an inner rotor portion and an outer rotor portion, and a double-sided yokeless stator. The yokeless stator includes modular lamination stacks and is configured for radial magnetic flux flow. The double-sided yokeless stator is concentrically disposed between the inner rotor portion and the outer rotor portion of the electrical machine. Examples of particularly useful embodiments for the electrical machine include wind turbine generators, ship propulsion motors, switch reluctance machines and double-sided synchronous machines.

  16. Simulation and experimental results of hybrid electric machine with a novel flux control strategy

    Directory of Open Access Journals (Sweden)

    Paplicki Piotr

    2015-03-01

    Full Text Available The paper presents selected simulation and experimental results of a hybrid ECPMS-machine (Electric Controlled Permanent Magnet Synchronous Machine. This permanent magnets (PMs excited machine offers an extended magnetic field control capability which makes it suitable for battery electric vehicle (BEV drives. Rotor, stator and the additional direct current control coil of the machine are analyzed in detail. The control system and strategy, the diagram of power supply system and an equivalent circuit model of the ECPMS-machine are presented. Influence of the additional excitation on the performance parameters of the machine, such as: torque, efficiency, speed limits and back-EMF have also been discussed.

  17. Electrical machines monitoring using partial discharges; Monitorizacion de maquinas electricas mediante descargas parciales

    Energy Technology Data Exchange (ETDEWEB)

    Cano, J. C.; Rodriguez Ruiz, S.

    2006-07-01

    Electrical Machines Monitoring is a philosophy that is being more and more accepted in maintenance, the application of these techniques has a lot of advantages as the life evaluation non-intrusively and the detection and evolution evaluation of defects. this paper presents the monitoring of electrical machines using the Partial Discharges technique, which allow the evaluation of insulation of Electrical Machines. Real Cases are included in the paper as samples in which this techniques has been useful to detecting defects. (Author)

  18. Electromagnetic Analysis and Design of Switched Reluctance Double-Rotor Machine for Hybrid Electric Vehicles

    OpenAIRE

    Shouliang Han; Shumei Cui; Liwei Song; Ching Chuen Chan

    2014-01-01

    The double-rotor machine is a kind of multiple input and output electromechanical energy transducer with two electrical ports and two mechanical ports, which is an ideal transmission system for hybrid electric vehicles and has a series of advantages such as integration of power and energy, high efficiency and compaction. In this paper, a switched reluctance double-rotor machine (SRDRM) is proposed for hybrid electric vehicles, while no conductor or PM in the middle rotor. This machine not onl...

  19. REMEDY OF WIRE LAG IN WIRE ELECTRICAL DISCHARGE MACHINING (WEDM

    Directory of Open Access Journals (Sweden)

    S. K. SINHA

    2010-12-01

    Full Text Available WEDM is extensively used these days for generating complex geometries with tight tolerances on difficult-tomachine materials. Therefore, demand for improvement in precision has been ever increasing. The main source of inaccuracy is wire-lag, the cause and effect of which is well-known. Research has been going on to overcome this drawback. So far, the techniques suggested for improvement in accuracy are, in general, based on monitoring the machining process at hardware-level, which is not only tedious but involves extra expenditure also. In the present paper, a software approach for improvement in accuracy is described, which does not require any additional investment on the machine, and still gives very good results.

  20. The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team.

    Science.gov (United States)

    Hrubiak, Rostislav; Sinogeikin, Stanislav; Rod, Eric; Shen, Guoyin

    2015-07-01

    We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here.

  1. The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team

    Energy Technology Data Exchange (ETDEWEB)

    Hrubiak, Rostislav; Sinogeikin, Stanislav; Rod, Eric; Shen, Guoyin [High Pressure Collaborative Access Team, Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois 60439 (United States)

    2015-07-15

    We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here.

  2. The laser micro-machining system for diamond anvil cell experiments and general precision machining applications at the High Pressure Collaborative Access Team

    Science.gov (United States)

    Hrubiak, Rostislav; Sinogeikin, Stanislav; Rod, Eric; Shen, Guoyin

    2015-07-01

    We have designed and constructed a new system for micro-machining parts and sample assemblies used for diamond anvil cells and general user operations at the High Pressure Collaborative Access Team, sector 16 of the Advanced Photon Source. The new micro-machining system uses a pulsed laser of 400 ps pulse duration, ablating various materials without thermal melting, thus leaving a clean edge. With optics designed for a tight focus, the system can machine holes any size larger than 3 μm in diameter. Unlike a standard electrical discharge machining drill, the new laser system allows micro-machining of non-conductive materials such as: amorphous boron and silicon carbide gaskets, diamond, oxides, and other materials including organic materials such as polyimide films (i.e., Kapton). An important feature of the new system is the use of gas-tight or gas-flow environmental chambers which allow the laser micro-machining to be done in a controlled (e.g., inert gas) atmosphere to prevent oxidation and other chemical reactions in air sensitive materials. The gas-tight workpiece enclosure is also useful for machining materials with known health risks (e.g., beryllium). Specialized control software with a graphical interface enables micro-machining of custom 2D and 3D shapes. The laser-machining system was designed in a Class 1 laser enclosure, i.e., it includes laser safety interlocks and computer controls and allows for routine operation. Though initially designed mainly for machining of the diamond anvil cell gaskets, the laser-machining system has since found many other micro-machining applications, several of which are presented here.

  3. Micro electrical discharge machining of small hole in TC4 alloy

    Institute of Scientific and Technical Information of China (English)

    LI Mao-sheng; CHI Guan-xin; WANG Zhen-long; WANG Yu-kui; DAI Li

    2009-01-01

    Aiming at machining deeply small holes in TC4 alloy, a series of experiments were carried out on a self-developed multi-axis micro electrical discharge machining (micro-EDM) machine tool. To improve machining efficiency and decrease relative wear of electrode in machining deeply small hole in TC4 alloy, many factors in micro-EDM, such as polarity, electrical parameters and supplying ways of working fluid were studied. Experimental results show that positive polarity machining is far superior to negative polarity machining; it is more optimal when open-circuit voltage, pulse width and pulse interval are 130 V, 5 μs and 15 μs respectively on the self developed multi-axis micro-EDM machine tool; when flushing method is applied in micro-EDM, the machining efficiency is higher and relative wear of electrode is smaller.

  4. 49 CFR 236.340 - Electromechanical interlocking machine; locking between electrical and mechanical levers.

    Science.gov (United States)

    2010-10-01

    ... between electrical and mechanical levers. 236.340 Section 236.340 Transportation Other Regulations..., STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND... Electromechanical interlocking machine; locking between electrical and mechanical levers. In...

  5. Pursuing optimal electric machines transient diagnosis: The adaptive slope transform

    Science.gov (United States)

    Pons-Llinares, Joan; Riera-Guasp, Martín; Antonino-Daviu, Jose A.; Habetler, Thomas G.

    2016-12-01

    The aim of this paper is to introduce a new linear time-frequency transform to improve the detection of fault components in electric machines transient currents. Linear transforms are analysed from the perspective of the atoms used. A criterion to select the atoms at every point of the time-frequency plane is proposed, taking into account the characteristics of the searched component at each point. This criterion leads to the definition of the Adaptive Slope Transform, which enables a complete and optimal capture of the different components evolutions in a transient current. A comparison with conventional linear transforms (Short-Time Fourier Transform and Wavelet Transform) is carried out, showing their inherent limitations. The approach is tested with laboratory and field motors, and the Lower Sideband Harmonic is captured for the first time during an induction motor startup and subsequent load oscillations, accurately tracking its evolution.

  6. Extreme learning machine for ranking: generalization analysis and applications.

    Science.gov (United States)

    Chen, Hong; Peng, Jiangtao; Zhou, Yicong; Li, Luoqing; Pan, Zhibin

    2014-05-01

    The extreme learning machine (ELM) has attracted increasing attention recently with its successful applications in classification and regression. In this paper, we investigate the generalization performance of ELM-based ranking. A new regularized ranking algorithm is proposed based on the combinations of activation functions in ELM. The generalization analysis is established for the ELM-based ranking (ELMRank) in terms of the covering numbers of hypothesis space. Empirical results on the benchmark datasets show the competitive performance of the ELMRank over the state-of-the-art ranking methods.

  7. Rotating electrical machines part 4: methods for determining synchronous machine quantities from tests

    CERN Document Server

    International Electrotechnical Commission. Geneva

    1985-01-01

    Applies to three-phase synchronous machines of 1 kVA rating and larger with rated frequency of not more than 400 Hz and not less than 15 Hz. An appendix gives unconfirmed test methods for determining synchronous machine quantities. Notes: 1 -Tests are not applicable to synchronous machines such as permanent magnet field machines, inductor type machines, etc. 2 -They also apply to brushless machines, but certain variations exist and special precautions should be taken.

  8. New Balancing Equipment for Mass Production of Small and Medium-Sized Electrical Machines

    DEFF Research Database (Denmark)

    Argeseanu, Alin; Ritchie, Ewen; Leban, Krisztina Monika

    2010-01-01

    The level of vibration and noise is an important feature. It is good practice to explain the significance of the indicators of the quality of electrical machines. The mass production of small and medium-sized electrical machines demands speed (short typical measurement time), reliability...

  9. Thermal Management and Reliability of Power Electronics and Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Narumanchi, Sreekant

    2016-08-03

    Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil -- by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, and in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines will be presented.

  10. Thermal Management and Reliability of Power Electronics and Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Narumanchi, Sreekant

    2016-06-13

    Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil - by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, and in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines are presented.

  11. Thermal Management and Reliability of Power Electronics and Electric Machines

    Energy Technology Data Exchange (ETDEWEB)

    Narumanchi, Sreekant

    2016-09-19

    Increasing the number of electric-drive vehicles (EDVs) on America's roads has been identified as a strategy with near-term potential for dramatically decreasing the nation's dependence on oil - by the U.S. Department of Energy, the federal cross-agency EV-Everywhere Challenge, and the automotive industry. Mass-market deployment will rely on meeting aggressive technical targets, including improved efficiency and reduced size, weight, and cost. Many of these advances will depend on optimization of thermal management. Effective thermal management is critical to improving the performance and ensuring the reliability of EDVs. Efficient heat removal makes higher power densities and lower operating temperatures possible, and in turn enables cost and size reductions. The National Renewable Energy Laboratory (NREL), along with DOE and industry partners is working to develop cost-effective thermal management solutions to increase device and component power densities. In this presentation, the activities in recent years related to thermal management and reliability of automotive power electronics and electric machines are presented.

  12. 29 October 2013 - Former Director-General of IAEA H. Blix on the occasion of the Thorium Energy Conference at CERN with Chair of the ThEC13 Organization Committee E. Lillestol and Author of the book “Atome Vert” (Green Atom) J.-C. de Mestral; in the LHC tunnel at Point 1 with Technology Department, Machine Protection & Electrical Integrity Group, Performance Evaluation Section Member A. Verweij.

    CERN Multimedia

    Anna Pantelia

    2013-01-01

    29 October 2013 - Former Director-General of IAEA H. Blix on the occasion of the Thorium Energy Conference at CERN with Chair of the ThEC13 Organization Committee E. Lillestol and Author of the book “Atome Vert” (Green Atom) J.-C. de Mestral; in the LHC tunnel at Point 1 with Technology Department, Machine Protection & Electrical Integrity Group, Performance Evaluation Section Member A. Verweij.

  13. Hybrid Forecasting Approach Based on GRNN Neural Network and SVR Machine for Electricity Demand Forecasting

    Directory of Open Access Journals (Sweden)

    Weide Li

    2017-01-01

    Full Text Available Accurate electric power demand forecasting plays a key role in electricity markets and power systems. The electric power demand is usually a non-linear problem due to various unknown reasons, which make it difficult to get accurate prediction by traditional methods. The purpose of this paper is to propose a novel hybrid forecasting method for managing and scheduling the electricity power. EEMD-SCGRNN-PSVR, the proposed new method, combines ensemble empirical mode decomposition (EEMD, seasonal adjustment (S, cross validation (C, general regression neural network (GRNN and support vector regression machine optimized by the particle swarm optimization algorithm (PSVR. The main idea of EEMD-SCGRNN-PSVR is respectively to forecast waveform and trend component that hidden in demand series to substitute directly forecasting original electric demand. EEMD-SCGRNN-PSVR is used to predict the one week ahead half-hour’s electricity demand in two data sets (New South Wales (NSW and Victorian State (VIC in Australia. Experimental results show that the new hybrid model outperforms the other three models in terms of forecasting accuracy and model robustness.

  14. Comparison and Analysis of Magnetic-Geared Permanent Magnet Electrical Machine at No-Load

    Directory of Open Access Journals (Sweden)

    Liu Xiping

    2014-12-01

    Full Text Available Magnetic-geared permanent magnet (MGPM electrical machine is a new type of machine by incorporating magnetic gear into PM electrical machine, and it may be in operation with low-speed, high-torque and direct-driven. In this paper, three types of MGPM machines are present, and a quantitative comparison among them is performed by finite element analysis (FEA. The magnetic field distribution, stable torque and back EMF are obtained at no-load. The results show that three types of MGPM machine are suitable for different application fields respectively according to their own advantages, such as high torque and back EMF, which form an important foundation for MGPM electrical machine research.

  15. Surface quality analysis of die steels in powder-mixed electrical discharge machining using titan powder in fine machining

    Directory of Open Access Journals (Sweden)

    Banh Tien Long

    2016-06-01

    Full Text Available Improving the quality of surface molds after electrical discharge machining is still being considered by many researchers. Powder-mixed dielectric in electrical discharge machining showed that it is one of the processing methods with high efficiency. This article reports on the results of surface quality of mold steels after powder-mixed electrical discharge machining using titanium powder in fine machining. The process parameters such as electrode material, workpiece material, electrode polarity, pulse on-time, pulse off-time, current, and titanium powder concentration were considered in the research. These materials are most commonly used with die-sinking electrical discharge machining in the manufacture of molds and has been selected as the subject of research: workpiece materials were SKD61, SKT4, and SKD11 mold steels, and electrode materials were copper and graphite. Taguchi’s method is used to design experiments. The influence of the parameters on surface roughness was evaluated through the average value and ratio (S/N. Results showed that the parameters such as electrical current, electrode material, pulse on-time, electrode polarity, and interaction between the electrode materials with concentration powder mostly influence surface roughness and surface roughness at optimal parameters SRopt = 1.73 ± 0.39 µm. Analysis of the surface layer after powder-mixed electrical discharge machining using titanium powder in optimal conditions has shown that the white layer with more uniform thickness and increased hardness (≈861.0 HV, and amount and size of microscopic cracks, is reduced. This significantly leads to the increase in the quality of the surface layer.

  16. Development and Application of Rare Earth Permanent Magnet (REPM) Material in Electric Machines

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    With the development of permanent materials, the development and application of permanent material electric machine (REPM) have been more mature. At first the state of development and application of REPM electric machine is presented in this paper, many RMEM have been produced in volume such as the pilot exciter used for power set of large-scale thermal power station, the special RMEM synchronous motor for textile, the starter motor for automobile, the brushless permanent magnet DC motor for electric facilities, permanent magnet servomotor for numerical controlled machine tool, rare-earth torque motor, special micro-motor for automobile and so on. Secondly the field of application of REPM electric machine and remaining problems is analyzed, because of the price of the rare-earth permanent magnet materials, the cost of RMEM is currently higher than that of induction machine, on the other side the dispersibility of performance of rare-earth permanent magnet materials and the limitation of technique of integral excitation are also remaining problems, above-mentioned problems handicapped the popularization of REPMEM. At last the developing prospect and trend of REPM electric machines is described, there are four promising types of PMEM: economical type, high performance type, high efficiency and energy-saving type, micromation, intelligibility type. With the appearance of new REPM material and the improvement of its performance and the continuous perfection of performance of electric-power electronic components, the development and the application of REPM electric machines will be further progressed.

  17. Electromagnetic Design of a New Electrically Controlled Magnetic Variable-Speed Gearing Machine

    Directory of Open Access Journals (Sweden)

    Chunhua Liu

    2014-03-01

    Full Text Available This paper proposes a new electrically controlled magnetic variable-speed gearing (EC-MVSG machine, which is capable of providing controllable gear ratios for hybrid electric vehicle (HEV applications. The key design feature involves the adoption of a magnetic gearing structure and acceptance of the memory machine flux-mnemonic concept. Hence, the proposed machine can not only offer a gear-shifting mechanism for torque and speed transmission, but also provide variable gear ratios for torque and speed variation. The electromagnetic design is studied and discussed. The finite-element method is developed with the hysteresis model to verify the validity of the machine design.

  18. Increase of energy efficiency of testing of traction electric machines of direct and pulsating current

    Directory of Open Access Journals (Sweden)

    A.M. Afanasov

    2015-03-01

    Full Text Available The results of the analysis of the effect of the load current of traction electric machines when tested for heating on the total electricity consumption for the test are presented. It is shown that increase of load current at the heating test permits to significantly reduce the consumption of electrical energy, and reduce the testing time without reducing its quality.

  19. Calibration of parallel kinematics machine using generalized distance error model

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper focus on the accuracy enhancement of parallel kinematics machine through kinematics calibration. In the calibration processing, well-structured identification Jacobian matrix construction and end-effector position and orientation measurement are two main difficulties. In this paper, the identification Jacobian matrix is constructed easily by numerical calculation utilizing the unit virtual velocity method. The generalized distance errors model is presented for avoiding measuring the position and orientation directly which is difficult to be measured. At last, a measurement tool is given for acquiring the data points in the calibration processing.Experimental studies confirmed the effectiveness of method. It is also shown in the paper that the proposed approach can be applied to other typed parallel manipulators.

  20. A Reformulation of Support Vector Machines for General Confidence Functions

    Science.gov (United States)

    Guo, Yuhong; Schuurmans, Dale

    We present a generalized view of support vector machines that does not rely on a Euclidean geometric interpretation nor even positive semidefinite kernels. We base our development instead on the confidence matrix—the matrix normally determined by the direct (Hadamard) product of the kernel matrix with the label outer-product matrix. It turns out that alternative forms of confidence matrices are possible, and indeed useful. By focusing on the confidence matrix instead of the underlying kernel, we can derive an intuitive principle for optimizing example weights to yield robust classifiers. Our principle initially recovers the standard quadratic SVM training criterion, which is only convex for kernel-derived confidence measures. However, given our generalized view, we are then able to derive a principled relaxation of the SVM criterion that yields a convex upper bound. This relaxation is always convex and can be solved with a linear program. Our new training procedure obtains similar generalization performance to standard SVMs on kernel-derived confidence functions, but achieves even better results with indefinite confidence functions.

  1. Iron Losses in Electrical Machines Due to Non Sinusoidal Alternating Fluxes

    DEFF Research Database (Denmark)

    Ritchie, Ewen; Walker, J.A.; Dorrell, D. G.

    2007-01-01

    This paper shows how the flux waveform in the core of an electrical machine can be vary non- sinusoidally which complicates the calculation of the iron loss in a machine. A set of tests are conducted on a steel sample using an Epstein square where harmonics are injected into the flux waveform which...

  2. Fractional Slot Concentrated Windings: A New Method to Manage the Mutual Inductance between Phases in Three-Phase Electrical Machines and Multi-Star Electrical Machines

    Directory of Open Access Journals (Sweden)

    Olivier Barre

    2015-06-01

    Full Text Available Mutual inductance is a phenomenon caused by the circulation of the magnetic flux in the core of an electrical machine. It is the result of the effect of the current flowing in one phase on the other phases. In conventional three-phase machines, such an effect has no influence on the electrical behaviour of the device. Although these machines are powered by power inverters, no problem should occur. The result is not the same for multi-star machines. If these machines are using a conventional winding structure, namely distributed windings, and are powered by voltage source converters, current ripples appear in the power supply lines. These current ripples are related to magnetic couplings between the stars. Designers should check these current ripples in order to stay within the limits imposed by the specifications. These electric current disturbances also provide torque ripples. With concentrated windings, a new degree of freedom appears; the configuration—number of slots/number of poles—can have a positive impact. The circulation of the magnetic flux is the initial phenomenon that produces the mutual inductance. The main goal of this discussion is to describe a design method that is able to produce not only a machine with low mutual inductance between phases, but also a multi-star machine where the stars and the phases are magnetically decoupled or less coupled. This discussion only takes into account the machines that use permanent magnets mounted on the rotor surface. This article is part of a study aimed at designing a high efficiency generator using fractional-slot concentrated-windings (FSCW.

  3. Numerical investigation of refrigeration machine compressor operation considering single-phase electric motor dynamic characteristics

    Science.gov (United States)

    Baidak, Y.; Smyk, V.

    2017-08-01

    Using as the base the differential equations system which was presented in relative units for generalized electric motor of hermetic refrigeration compressor, mathematical model of the software for dynamic performance calculation of refrigeration machine compressors drive low-power asynchronous motors was developed. Performed on its ground calculations of the basic model of two-phase electric motor drive of hermetic compressor and the proposed newly developed model of the motor with single-phase stator winding, which is an alternative to the industrial motor winding, have confirmed the benefits of the motor with innovative stator winding over the base engine. Given calculations of the dynamic characteristics of compressor drive motor have permitted to determine the value of electromagnetic torque swinging for coordinating compressor and motor mechanical characteristics, and for taking them into consideration in choosing compressor elements construction materials. Developed and used in the process of investigation of refrigeration compressor drive asynchronous single-phase motor mathematical and software can be considered as an element of computer-aided design system for design of the aggregate of refrigeration compression unit refrigerating machine.

  4. USING OF OBJECT-ORIENTED DESIGN PRINCIPLES IN ELECTRIC MACHINES DEVELOPMENT

    OpenAIRE

    Zablodskii, N. N.; V.E. Pliugin; A.N. Petrenko

    2016-01-01

    Purpose. To develop the theoretical basis of electrical machines object-oriented design, mathematical models and software to improve their design synthesis, analysis and optimization. Methodology. We have applied object-oriented design theory in electric machines optimal design and mathematical modelling of electromagnetic transients and electromagnetic field distribution. We have correlated the simulated results with the experimental data obtained by means of the double-stator screw dryer wi...

  5. Surface Modification Process by Electrical Discharge Machining with Ti Powder Green Compact Electrode

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper describes a new method of surface modification by Electrical Discharge Machining (EDM). By using ordinary EDM machine tool and kerosene fluid, a hard ceramic layer can be created on the workpiece surface with Ti or other compressed powder electrode in a certain condition. This new revolutionary method is called Electrical Discharge Coating (EDC). The process of EDC begins with electrode wear during EDM,then a kind of hard carbide is created through the thermal and chemical reaction between the wo...

  6. Method and system employing finite state machine modeling to identify one of a plurality of different electric load types

    Energy Technology Data Exchange (ETDEWEB)

    Du, Liang; Yang, Yi; Harley, Ronald Gordon; Habetler, Thomas G.; He, Dawei

    2016-08-09

    A system is for a plurality of different electric load types. The system includes a plurality of sensors structured to sense a voltage signal and a current signal for each of the different electric loads; and a processor. The processor acquires a voltage and current waveform from the sensors for a corresponding one of the different electric load types; calculates a power or current RMS profile of the waveform; quantizes the power or current RMS profile into a set of quantized state-values; evaluates a state-duration for each of the quantized state-values; evaluates a plurality of state-types based on the power or current RMS profile and the quantized state-values; generates a state-sequence that describes a corresponding finite state machine model of a generalized load start-up or transient profile for the corresponding electric load type; and identifies the corresponding electric load type.

  7. Advances in three-dimensional field analysis and evaluation of performance parameters of electrical machines

    Science.gov (United States)

    Sivasubramaniam, Kiruba

    This thesis makes advances in three dimensional finite element analysis of electrical machines and the quantification of their parameters and performance. The principal objectives of the thesis are: (1)the development of a stable and accurate method of nonlinear three-dimensional field computation and application to electrical machinery and devices; and (2)improvement in the accuracy of determination of performance parameters, particularly forces and torque computed from finite elements. Contributions are made in two general areas: a more efficient formulation for three dimensional finite element analysis which saves time and improves accuracy, and new post-processing techniques to calculate flux density values from a given finite element solution. A novel three-dimensional magnetostatic solution based on a modified scalar potential method is implemented. This method has significant advantages over the traditional total scalar, reduced scalar or vector potential methods. The new method is applied to a 3D geometry of an iron core inductor and a permanent magnet motor. The results obtained are compared with those obtained from traditional methods, in terms of accuracy and speed of computation. A technique which has been observed to improve force computation in two dimensional analysis using a local solution of Laplace's equation in the airgap of machines is investigated and a similar method is implemented in the three dimensional analysis of electromagnetic devices. A new integral formulation to improve force calculation from a smoother flux-density profile is also explored and implemented. Comparisons are made and conclusions drawn as to how much improvement is obtained and at what cost. This thesis also demonstrates the use of finite element analysis to analyze torque ripples due to rotor eccentricity in permanent magnet BLDC motors. A new method for analyzing torque harmonics based on data obtained from a time stepping finite element analysis of the machine is

  8. Strategic Optimization and Investigation Effect Of Process Parameters On Performance Of Wire Electric Discharge Machine (WEDM

    Directory of Open Access Journals (Sweden)

    ATUL KUMAR

    2012-06-01

    Full Text Available Wire electrical discharge machining (WEDM is widely used in machining of conductive materials when precision is of primary significance. Wire-cut electric discharge machining of Skd 61alloy has been considered in the present work. Experimentation has been completed by using Taguchi’s L18 (21x37 orthogonal array under different conditions of parameters. Optimal combinations of parameters were obtained by this technique. The study shows that with the minimum number of experiments the complete problem can be solvedwhen compared to full factorial design. Experimental results make obvious that the machining model is proper and the Taguchi’s method satisfies the practical conditions. The results obtained are analyzed for the selection of an optimal combination of WEDM parameters for proper machining of Skd 61 alloy to achieve better surface finish. Different analysis was made on the data obtained from the experiments.

  9. Development of new metal matrix composite electrodes for electrical discharge machining through powder metallurgy process

    Directory of Open Access Journals (Sweden)

    C. Mathalai Sundaram

    2014-12-01

    Full Text Available Electrical discharge machining (EDM is one of the widely used nontraditional machining methods to produce die cavities by the erosive effect of electrical discharges. This method is popular due to the fact that a relatively soft electrically conductive tool electrode can machine hard work piece. Copper electrode is normally used for machining process. Electrode wear rate is the major drawback for EDM researchers. This research focus on fabrication of metal matrix composite (MMC electrode by mixing copper powder with titanium carbide (TiC and Tungsten carbide (WC powder through powder metallurgy process, Copper powder is the major amount of mixing proportion with TiC and WC. However, this paper focus on the early stage of the project where powder metallurgy route was used to determine suitable mixing time, compaction pressure and sintering and compacting process in producing EDM electrode. The newly prepared composite electrodes in different composition are tested in EDM for OHNS steel.

  10. Sustainable Electric Vehicle Management using Coordinated Machine Learning

    NARCIS (Netherlands)

    K. Valogianni (Konstantina)

    2016-01-01

    markdownabstractThe purpose of this dissertation is to investigate how intelligent algorithms can support electricity customers in their complex decisions within the electricity grid. In particular, we focus on how electric vehicle (EV) owners can be supported in their charging and discharging

  11. Sustainable Electric Vehicle Management using Coordinated Machine Learning

    NARCIS (Netherlands)

    K. Valogianni (Konstantina)

    2016-01-01

    markdownabstractThe purpose of this dissertation is to investigate how intelligent algorithms can support electricity customers in their complex decisions within the electricity grid. In particular, we focus on how electric vehicle (EV) owners can be supported in their charging and discharging decis

  12. USING OF OBJECT-ORIENTED DESIGN PRINCIPLES IN ELECTRIC MACHINES DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    N.N. Zablodskii

    2016-03-01

    Full Text Available Purpose. To develop the theoretical basis of electrical machines object-oriented design, mathematical models and software to improve their design synthesis, analysis and optimization. Methodology. We have applied object-oriented design theory in electric machines optimal design and mathematical modelling of electromagnetic transients and electromagnetic field distribution. We have correlated the simulated results with the experimental data obtained by means of the double-stator screw dryer with an external solid rotor, brushless turbo-generator exciter and induction motor with squirrel cage rotor. Results. We have developed object-oriented design methodology, transient mathematical modelling and electromagnetic field equations templates for cylindrical electrical machines, improved and remade Cartesian product and genetic optimization algorithms. This allows to develop electrical machines classifications models, included not only structure development but also parallel synthesis of mathematical models and design software, to improve electric machines efficiency and technical performance. Originality. For the first time, we have applied a new way of design and modelling of electrical machines, which is based on the basic concepts of the object-oriented analysis. For the first time is suggested to use a single class template for structural and system organization of electrical machines, invariant to their specific variety. Practical value. We have manufactured screw dryer for coil dust drying and mixing based on the performed object-oriented theory. We have developed object-oriented software for design and optimization of induction motor with squirrel cage rotor of AIR series and brushless turbo-generator exciter. The experimental studies have confirmed the adequacy of the developed object-oriented design methodology.

  13. Distributed model for electromechanical interaction in rotordynamics of cage rotor electrical machines

    Science.gov (United States)

    Laiho, Antti; Holopainen, Timo P.; Klinge, Paul; Arkkio, Antero

    2007-05-01

    In this work the effects of the electromechanical interaction on rotordynamics and vibration characteristics of cage rotor electrical machines were considered. An eccentric rotor motion distorts the electromagnetic field in the air-gap between the stator and rotor inducing a total force, the unbalanced magnetic pull, exerted on the rotor. In this paper a low-order parametric model for the unbalanced magnetic pull is coupled with a three-dimensional finite element structural model of the electrical machine. The main contribution of the work is to present a computationally efficient electromechanical model for vibration analysis of cage rotor machines. In this model, the interaction between the mechanical and electromagnetic systems is distributed over the air gap of the machine. This enables the inclusion of rotor and stator deflections into the analysis and, thus, yields more realistic prediction for the effects of electromechanical interaction. The model was tested by implementing it for two electrical machines with nominal speeds close to one of the rotor bending critical speeds. Rated machine data was used in order to predict the effects of the electromechanical interaction on vibration characteristics of the example machines.

  14. Electric Traction Machine Design for an E-RWD Unit

    OpenAIRE

    Marquez, Francisco

    2014-01-01

    Since the first generation of the Toyota Prius was introduced in December 1997, the number of Hybrid Electric Vehicles (HEVs) and pure Electric Vehicles (EVs) available in the market has increased substantially. The growing competition existent puts high demands on the electric system as well as the rest of the vehicle. As a consequence, substantial design effort is devoted to optimize both at system and component level, with respect to different parameters such as fuel efficiency, power dens...

  15. Electromechanical Battery EMB Mass Minimization taking into Account its Electrical Machines Rotor Energy

    Directory of Open Access Journals (Sweden)

    Podgornovs Andrejs

    2014-12-01

    Full Text Available In this paper the electromechanical battery (EMB with synchronous machine is described. Theoretically, if electrical machines rotor stored energy is known, it is possible to reduce the flywheel mass of electromechanical battery. For example, the efficiency of energy recovery (kilowatt-hours out versus kilowatthours in in nowadays appliances exceeds 95 % which is considerably better than of any electrochemical battery, such as lead-acid battery. For the rotor stored energy amount calculation, it is necessary to find all geometrical dimensions of the electrical machine. To achieve this goal the iterative calculation method was used. Electromechanical battery mass was analyzed as a discharge process rotation speed function. Taking into account the rotor stored energy, we can increase the minimum rotation speed thus reducing the electrical machine mass and increasing the flywheel mass, which provides EMB cost reduction. Additionally, the possibilities of using numerical approximation calculations of magnetization curves are discussed. Each iteration of numerical application necessary for the method for rapid calculation is essential when calculating the field problems. Nowadays there are a lot of computer added design programs for electromagnetic field calculation in different types of applications, electrical machines and apparatus. For the electromagnetic field calculation process some more commonly used magnetization curve approximation methods are described, and the machine calculation time is tested for different numbers of calculations.

  16. Electrical engineering. Coiling of rotating machines; Genie electrique. Bobinage des machines tournantes a courant alternatif

    Energy Technology Data Exchange (ETDEWEB)

    Saint-Michel, J. [Moteurs Leroy Somer, 16 - Angouleme (France)

    2001-02-01

    This article treats of the poly-phase coiling of AC rotating machines. For simplification reasons, the study has been limited to tri-phase coils, but the theoretical calculations can be extended to any other number of phases. The coils described are those encountered in the stators of synchronous and asynchronous machines and in the rotors of asynchronous machines with rings. The qualitative, quantitative and practical aspects are presented successively: 1 - magnetic field produced by a coil (single turn, distributed coil, coil schemes, multi-polarity coils); 2 - field generated by a tri-phase coil (rotating field theorem, qualitative influence of space harmonics); 3 - quantitative analysis of coil properties (magneto-motive force generated by coils, harmonic decomposition of the magneto-motive force wave, global coiling coefficients); 4 - comparative study of different regular coils (diametrical step, shortened step, distributed); 5 - irregular coils; 6 - other double polarity coils (Dahlander coupling, other multiple polarity possibilities); 7 - reduction of teething harmonics (determination of optimal twisting, influence of inclination on the dimensioning of machines); 8 - practical realization of coils (insulation, insertion inside the machine). (J.S.)

  17. 29 CFR 1910.212 - General requirements for all machines.

    Science.gov (United States)

    2010-07-01

    ...) Alligator shears. (d) Power presses. (e) Milling machines. (f) Power saws. (g) Jointers. (h) Portable power... blades. When the periphery of the blades of a fan is less than seven (7) feet above the floor or...

  18. Two General Architectures for Intelligent Machine Performance Degradation Assessment

    Directory of Open Access Journals (Sweden)

    Yanwei Xu

    2015-01-01

    Full Text Available Markov model is of good ability to infer random events whose likelihood depends on previous events. Based on this theory, hidden Markov model serves as an extension of Markov model to present an event from observations rather than states in Markov model. Moreover, due to successful applications in speech recognition, it attracts much attention in machine fault diagnosis. This paper presents two architectures for machine performance degradation assessment, which can be used to minimize machine downtime, reduce economic loss, and improve productivity. The major difference between the two architectures is whether historical data are available to build hidden Markov models. In case studies, bearing data as well as available historical data are used to demonstrate the effectiveness of the first architecture. Then, whole life gearbox data without historical data are employed to demonstrate the effectiveness of the second architecture. The results obtained from two case studies show that the presented architectures have good abilities for machine performance degradation assessment.

  19. A chronic generalized bi-directional brain-machine interface

    Science.gov (United States)

    Rouse, A. G.; Stanslaski, S. R.; Cong, P.; Jensen, R. M.; Afshar, P.; Ullestad, D.; Gupta, R.; Molnar, G. F.; Moran, D. W.; Denison, T. J.

    2011-06-01

    A bi-directional neural interface (NI) system was designed and prototyped by incorporating a novel neural recording and processing subsystem into a commercial neural stimulator architecture. The NI system prototype leverages the system infrastructure from an existing neurostimulator to ensure reliable operation in a chronic implantation environment. In addition to providing predicate therapy capabilities, the device adds key elements to facilitate chronic research, such as four channels of electrocortigram/local field potential amplification and spectral analysis, a three-axis accelerometer, algorithm processing, event-based data logging, and wireless telemetry for data uploads and algorithm/configuration updates. The custom-integrated micropower sensor and interface circuits facilitate extended operation in a power-limited device. The prototype underwent significant verification testing to ensure reliability, and meets the requirements for a class CF instrument per IEC-60601 protocols. The ability of the device system to process and aid in classifying brain states was preclinically validated using an in vivo non-human primate model for brain control of a computer cursor (i.e. brain-machine interface or BMI). The primate BMI model was chosen for its ability to quantitatively measure signal decoding performance from brain activity that is similar in both amplitude and spectral content to other biomarkers used to detect disease states (e.g. Parkinson's disease). A key goal of this research prototype is to help broaden the clinical scope and acceptance of NI techniques, particularly real-time brain state detection. These techniques have the potential to be generalized beyond motor prosthesis, and are being explored for unmet needs in other neurological conditions such as movement disorders, stroke and epilepsy.

  20. Electrical engineering. Rotating machines: principles and constitution; Genie electrique. Machines tournantes: principes et constitution

    Energy Technology Data Exchange (ETDEWEB)

    Nogarede, B. [Ecole Nationale Superieure d' Electrotechnique, d' Electronique, d' Informatique, D' hydraulique, ENSEEIHT/INPT, LEEI, 31 - Toulouse (France)

    2001-02-01

    This article deals specifically with rotating machines with magnetic fields interaction. The elementary principles are globally analyzed and characterized using an original analytical approach. Some aspects and trends relative to the materials used are given. The last part treats of the methodological aspects of the optimal dimensioning of a machine according to given specifications and criteria: 1 - rotating machines with magnetic fields interaction (creation of rotating magnetic fields, energy conversion with rotating magnetic moments and fields interaction, structures with produced magnetic moments, structures with induced magnetic moments, switching notions); 2 - components of active parts and materials used (magnetic circuits and field sources, conductors and superconductors, electro-active materials); 3 - design of electromechanical converters (main steps of the design process, different methodological levels in presence, from the design to the dimensioned structure (optimized design)). (J.S.)

  1. VIBRATION SENSOR FOR HEALTH MONITORING OF ELECTRICAL MACHINES IN POWER STATION

    Directory of Open Access Journals (Sweden)

    Neha Gupta

    2012-04-01

    Full Text Available Vibration monitoring in high power electric machines, such as generators and transformers, presents some difficulties due to the insulation and EM immunity requirements .However, the negative influence of the electromagnetic interference (EMI can be a real problem when electrical signals are used to detect and transmitphysical parameters in noisy environments such as electric power generator plants with high levels of EMI. Such problems can be solved using optical fiber sensors, which allow in situ measurements and remote control without electrical wires. The present paper describes a novel fiber optic vibration sensor for health monitoring of electrical machines, which utilizes relatively simple technologies and offers moderate costs. The sensor is optimized for detection of mechanical vibrations in the frequency range 20-100 Hz. Design details and experimental results are reported.

  2. Convection Heat Transfer and Flow Calculations Suitable for Electric Machines Thermal Models

    OpenAIRE

    Cavagnino, Andrea

    2008-01-01

    This paper deals with the formulations used to predict convection cooling and flow in electric machines. Empirical dimensionless analysis formulations are used to calculate convection heat transfer. The particular formulation used is selected to match the geometry of the surface under consideration and the cooling type used. Flow network analysis, which is used to study the ventilation inside the machine, is also presented. In order to focus the discussion using examples, a commercial softwar...

  3. Electrical machine characterisation and analysis for renewable energy applications

    OpenAIRE

    Cashman, David P.

    2010-01-01

    There has been an increased use of the Doubly-Fed Induction Machine (DFIM) in ac drive applications in recent times, particularly in the field of renewable energy systems and other high power variable-speed drives. The DFIM is widely regarded as the optimal generation system for both onshore and offshore wind turbines and has also been considered in wave power applications. Wind power generation is the most mature renewable technology. However, wave energy has attracted a large interest recen...

  4. Feasibility Study for Electrical Discharge Machining of Large DU-Mo Castings

    Energy Technology Data Exchange (ETDEWEB)

    Hill, Mary Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Dombrowski, David E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Clarke, Kester Diederik [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Forsyth, Robert Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Aikin, Robert M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Alexander, David John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Tegtmeier, Eric Lee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Robison, Jeffrey Curt [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Beard, Timothy Vance [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Edwards, Randall Lynn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Mauro, Michael Ernest [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Scott, Jeffrey E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division; Strandy, Matthew Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). SIGMA Division

    2016-10-31

    U-10 wt. % Mo (U-10Mo) alloys are being developed as low enrichment monolithic fuel for the CONVERT program. Optimization of processing for the monolithic fuel is being pursued with the use of electrical discharge machining (EDM) under CONVERT HPRR WBS 1.2.4.5 Optimization of Coupon Preparation. The process is applicable to manufacturing experimental fuel plate specimens for the Mini-Plate-1 (MP-1) irradiation campaign. The benefits of EDM are reduced machining costs, ability to achieve higher tolerances, stress-free, burr-free surfaces eliminating the need for milling, and the ability to machine complex shapes. Kerf losses are much smaller with EDM (tenths of mm) compared to conventional machining (mm). Reliable repeatability is achievable with EDM due to its computer-generated machining programs.

  5. Position Error Compensation via a Variable Reluctance Sensor Applied to a Hybrid Vehicle Electric Machine

    Directory of Open Access Journals (Sweden)

    İhsan Ömür Bucak

    2010-03-01

    Full Text Available In the automotive industry, electromagnetic variable reluctance (VR sensors have been extensively used to measure engine position and speed through a toothed wheel mounted on the crankshaft. In this work, an application that already uses the VR sensing unit for engine and/or transmission has been chosen to infer, this time, the indirect position of the electric machine in a parallel Hybrid Electric Vehicle (HEV system. A VR sensor has been chosen to correct the position of the electric machine, mainly because it may still become critical in the operation of HEVs to avoid possible vehicle failures during the start-up and on-the-road, especially when the machine is used with an internal combustion engine. The proposed method uses Chi-square test and is adaptive in a sense that it derives the compensation factors during the shaft operation and updates them in a timely fashion.

  6. Position error compensation via a variable reluctance sensor applied to a Hybrid Vehicle Electric machine.

    Science.gov (United States)

    Bucak, Ihsan Ömür

    2010-01-01

    In the automotive industry, electromagnetic variable reluctance (VR) sensors have been extensively used to measure engine position and speed through a toothed wheel mounted on the crankshaft. In this work, an application that already uses the VR sensing unit for engine and/or transmission has been chosen to infer, this time, the indirect position of the electric machine in a parallel Hybrid Electric Vehicle (HEV) system. A VR sensor has been chosen to correct the position of the electric machine, mainly because it may still become critical in the operation of HEVs to avoid possible vehicle failures during the start-up and on-the-road, especially when the machine is used with an internal combustion engine. The proposed method uses Chi-square test and is adaptive in a sense that it derives the compensation factors during the shaft operation and updates them in a timely fashion.

  7. CAD-CAE in Electrical Machines and Drives Teaching.

    Science.gov (United States)

    Belmans, R.; Geysen, W.

    1988-01-01

    Describes the use of computer-aided design (CAD) techniques in teaching the design of electrical motors. Approaches described include three technical viewpoints, such as electromagnetics, thermal, and mechanical aspects. Provides three diagrams, a table, and conclusions. (YP)

  8. Shaping of steel mold surface of lens array by electrical discharge machining with single rod electrode.

    Science.gov (United States)

    Takino, Hideo; Hosaka, Takahiro

    2014-11-20

    We propose a method for fabricating a lens array mold by electrical discharge machining (EDM). In this method, the tips of rods are machined individually to form a specific surface, and then a number of the machined rods are arranged to construct an electrode for EDM. The repetition of the EDM process using the electrode enables a number of lens elements to be produced on the mold surface. The effectiveness of our proposed method is demonstrated by shaping a lens array mold made of stainless steel with 16 spherical elements, in which the EDM process with a single rod electrode is repeatedly conducted.

  9. A Review of Research on Improvement and Optimization of Performance Measures for Electrical Discharge Machining

    Directory of Open Access Journals (Sweden)

    C. R. Sanghani

    2014-01-01

    Full Text Available Electrical Discharge Machining (EDM is a non conventional machining method which can be used to machine electrically conductive work pieces irrespective of their shape, hardness and toughness. High cost of non conventional machine tools, compared to conventional machining, has forced us to operate these machines as efficiently as possible in order to reduce production cost and to obtain the required reimbursement. To achieve this task, machining parameters such as pulse on time, pulse off time, discharge current, gap voltage, flushing pressure, electrode material, etc. of this process should be selected such that optimal value of their performance measures like Material Removal Rate (MRR, Surface Roughness (SR, Electrode/Tool Wear Rate (EWR/TWR, dimensional accuracy, etc. can be obtained or improved. In past decades, intensive research work had been carried out by different researchers for improvement and optimization of EDM performance measures using various optimization techniques like Taguchi, Response Surface Methodology (RSM, Artificial Neural Network (ANN, Genetic Algorithm (GA, etc. This paper reviews research on improvement and optimization of various performance measures of spark erosion EDM and finally lists down certain areas that can be taken up for further research in the field of improvement and optimization for EDM process.

  10. Effects of sandblasting and electrical discharge machining on porcelain adherence to cast and machined commercially pure titanium.

    Science.gov (United States)

    Inan, Ozgür; Acar, Asli; Halkaci, Selçuk

    2006-08-01

    The aim of this study was to determine the effect of sandblasting and electrical discharge machining (EDM) on cast and machined titanium surfaces and titanium-porcelain adhesion. Twenty machined titanium specimens were prepared by manufacturer (groups 1 and 2). Thirty specimens were prepared with autopolymerizing acrylic resin. Twenty of these specimens (groups 3 and 4) were cast with commercially pure titanium and the alpha-case layer was removed. For control group (group 5), 10 specimens were cast by using NiCr alloy. Groups 2 and 4 were subjected to EDM while groups 1, 3, and 5 were subjected to sandblasting. Surface examinations were made by using a scanning electron microscope (SEM). A low-fusing porcelain was fused on the titanium surfaces, whereas NiCr specimens were covered using a conventional porcelain. Titanium-porcelain adhesion was characterized by a 3-point bending test. Results were analyzed by Kruskal-Wallis and Mann-Whitney U tests. Metal-porcelain interfaces were characterized by SEM. The bond strength of control group was higher than that of the titanium-porcelain system. There was no significant difference between cast and machined titanium groups (p > 0.05). There was no significant difference between EDM and sandblasting processes (p > 0.05). The use of EDM as surface treatment did not improve titanium-porcelain adhesion compared with sandblasting.

  11. Comparison of stator-mounted permanent-magnet machines based on a general power equation

    DEFF Research Database (Denmark)

    Chen, Zhe; Hua, Wei; Cheng, Ming

    2009-01-01

    The stator-mounted permanent-magnet (SMPM) machines have some advantages compared with its counterparts, such as simple rotor, short winding terminals, and good thermal dissipation conditions for magnets. In this paper, a general power equation for three types of SMPM machine is introduced first......, and then, power equations considering the specific topologies are derived. Based on these power equations, theoretical comparisons are carried out between various types of the SMPM machines. In all, eight topologies have been presented and benchmarked. It reveals that the flux switching permanent......-magnet (PM) machine owns higher power density than the flux reversal PM machine and the doubly salient PM machine under same outer diameter. The comparison based on the power equation has established a foundation for optimizing the SMPM machines....

  12. Specification Requirement for Thermal Stability of Sintered NdFeB Materials for Electrical Machines

    Institute of Scientific and Technical Information of China (English)

    Lin Yan; Jiang Daiwei; Chen Lixiang; Chen Hailing; Bi Haitao; Tang Renyuan

    2004-01-01

    Based on IEC standards and Chinese national standards of sintered NdFeB materials, in the paper the hightemperature, room-temperature properties and thermal stability of about one hundred samples of NdFeB materials for electrical machines were measured and analyzed.These materials are produced by ten representative manufactories in China.Combined with the analysis results, the paper points out that the magnetic properties of sintered NdFeB materials for electrical machines should meet not only the specific values in standards, such as Br, (BH)max ,HcJ ,but also the requirement of temperature coefficients a (Br) , a (HcJ).

  13. Electric motor assisted bicycle as an aerobic exercise machine.

    Science.gov (United States)

    Nagata, T; Okada, S; Makikawa, M

    2012-01-01

    The goal of this study is to maintain a continuous level of exercise intensity around the aerobic threshold (AT) during riding on an electric motor assisted bicycle using a new control system of electrical motor assistance which uses the efficient pedaling rate of popular bicycles. Five male subjects participated in the experiment, and the oxygen uptake was measured during cycling exercise using this new pedaling rate control system of electrical motor assistance, which could maintain the pedaling rate within a specific range, similar to that in previous type of electrically assisted bicycles. Results showed that this new pedaling rate control system at 65 rpm ensured continuous aerobic exercise intensity around the AT in two subjects, and this intensity level was higher than that observed in previous type. However, certain subjects were unable to maintain the expected exercise intensity because of their particular cycling preferences such as the pedaling rate. It is necessary to adjust the specific pedaling rate range of the electrical motor assist control according to the preferred pedaling rate, so that this system becomes applicable to anyone who want continuous aerobic exercise.

  14. Optimization of Process Parameters in Wire Electrical Discharge Machining of MMC: A Review

    Directory of Open Access Journals (Sweden)

    J.M.Pujara

    2015-07-01

    Full Text Available Wire electrical discharge machining (WEDM is a specialized thermal machining process capable of accurately machining parts with varying hardness or complex shapes, which have sharp edges that are very difficult to be machined by the main stream machining processes. This practical technology of the WEDM process is based on the conventional EDM sparking phenomenon utilizing the widely accepted non-contact technique of material removal. Since the introduction of the process, WEDM has evolved from a simple means of making tools and dies to the best alternative of producing micro-scale parts with the highest degree of dimensional accuracy and surface finish quality. Metal matrix composites are advanced materials having high specific strength, good wear resistance, and high thermal expansion coefficient. To achieve this task, machining parameters such as pulse on time, pulse off time, peak current, servo voltage, wire feed, wire tension etc. of this process should be selected such that optimal value of their performance measures like Material Removal Rate (MRR, Surface Roughness (SR, Gap current, Dimensional deviation, etc. can be obtained or improved. In past decades, intensive research work had been carried out by different researchers for improvement and optimization of WEDM performance measures using various optimization techniques like Taguchi, Response Surface Methodology (RSM, Artificial Neural Network (ANN, Genetic Algorithm (GA, etc. This paper also highlights the feasibility of the different control strategies of obtaining the optimal machining conditions. This literature review helps to identify the suitable process parameters and their ranges in machining of metal matrix composites.

  15. Electromagnetic Analysis and Design of Switched Reluctance Double-Rotor Machine for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Shouliang Han

    2014-10-01

    Full Text Available The double-rotor machine is a kind of multiple input and output electromechanical energy transducer with two electrical ports and two mechanical ports, which is an ideal transmission system for hybrid electric vehicles and has a series of advantages such as integration of power and energy, high efficiency and compaction. In this paper, a switched reluctance double-rotor machine (SRDRM is proposed for hybrid electric vehicles, while no conductor or PM in the middle rotor. This machine not only inherits the merits of switched reluctance machine, such as simple salient rotor structure, high reliability and wide speed range, but also can avoid the outer rotor’s cooling problem effectively. By using an equivalent magnetic circuit model, the function of middle rotor yoke is analyzed. Electromagnetic analyses of the SRDRM are performed with analytical calculations and 2-D finite element methods, including the effects of main parameters on performance. Finally, a 4.4 kW prototype machine is designed and manufactured, and the tests are performed, which validate the proposed design method.

  16. Remediation, General Education, and Technical Mathematics. Educational Resources for the Machine Tool Industry.

    Science.gov (United States)

    Texas State Technical Coll. System, Waco.

    This document contains descriptions of adult education courses in remediation, general education, and technical mathematics. They are part of a program developed by the Machine Tool Advanced Skills Technology Educational Resources (MASTER) program to help workers become competent in the skills needed to be productive workers in the machine tools…

  17. A general thermal model of machine tool spindle

    Directory of Open Access Journals (Sweden)

    Yanfang Dong

    2017-01-01

    Full Text Available As the core component of machine tool, the thermal characteristics of the spindle have a significant influence on machine tool running status. Lack of an accurate model of the spindle system, particularly the model of load–deformation coefficient between the bearing rolling elements and rings, severely limits the thermal error analytic precision of the spindle. In this article, bearing internal loads, especially the function relationships between the principal curvature difference F(ρ and auxiliary parameter nδ, semi-major axis a, and semi-minor axis b, have been determined; furthermore, high-precision heat generation combining the heat sinks in the spindle system is calculated; finally, an accurate thermal model of the spindle was established. Moreover, a conventional spindle with embedded fiber Bragg grating temperature sensors has been developed. By comparing the experiment results with simulation, it indicates that the model has good accuracy, which verifies the reliability of the modeling process.

  18. Impacts of Interior Permanent Magnet Machine Technology for Electric Vehicles

    Science.gov (United States)

    2012-01-01

    system forms the backbone of modern society. Electricity and its accessibility is one of the major engineering achievements. In order to maintain and...Minimum weight and smallest size  Low fuel consumption rate (litre/km)  New ICE engine technology with hybrid gasoline/diesel  Homogenous...charge-compression ignition ( HCCI )  Clean and environmentally benign  Quiet, smooth and comfortable ride  Better battery power and self-charging

  19. Application of Tabu Search to UPFC Stabilizer Adjustment at a Multi Machine Electric Power System

    Directory of Open Access Journals (Sweden)

    Hasan Fayazi Boroujeni

    2012-04-01

    Full Text Available Unified Power Flow Controller (UPFC is one of the most viable and important Flexible AC Transmission Systems (FACTS devises. Application of UPFC in single machine and multi machine electric power systems has been investigated with different purposes such as power transfer capability, damping of Low Frequency Oscillations (LFO, voltage support and so forth. But, an important issue in UPFC applications is to find optimal parameters of UPFC controllers. This paper presents the application of Unified Power Flow Controller (UPFC to enhance dynamic stability of a multi-machine electric power system. A supplementary stabilizer based on UPFC (like power system stabilizer is designed to reach the defined purpose. An intelligence optimization method based on Tabu Search (TS is considered for tuning the parameters of UPFC supplementary stabilizer. Several nonlinear time-domain simulation tests visibly show the ability of UPFC in damping of power system oscillations and consequently stability enhancement.

  20. Support Vector Machines for decision support in electricity markets׳ strategic bidding

    DEFF Research Database (Denmark)

    Pinto, Tiago; Sousa, Tiago M.; Praça, Isabel

    2015-01-01

    . The ALBidS system allows MASCEM market negotiating players to take the best possible advantages from the market context. This paper presents the application of a Support Vector Machines (SVM) based approach to provide decision support to electricity market players. This strategy is tested and validated...... – Iberian market operator....

  1. Traveling wire electrode increases productivity of Electrical Discharge Machining /EDM/ equipment

    Science.gov (United States)

    Kotora, J., Jr.; Smith, S. V.

    1967-01-01

    Traveling wire electrode on electrical discharge machining /EDM/ equipment reduces the time requirements for precision cutting. This device enables cutting with a minimum of lost material and without inducing stress beyond that inherent in the material. The use of wire increases accuracy and enables tighter tolerances to be maintained.

  2. Improving energy utilization efficiency of electrical discharge milling in titanium alloys machining

    Institute of Scientific and Technical Information of China (English)

    郭成波; 韦东波; 狄士春

    2016-01-01

    Electrical discharge milling (ED-milling) can be a good choice for titanium alloys machining and it was proven that its machining efficiency can be improved to compete with mechanical cutting. In order to improve energy utilization efficiency of ED-milling process, unstable arc discharge and stable arc discharge combined with normal discharge were implemented for material removal by adjusting servo control strategy. The influence of electrode rotating speed and dielectric flushing pressure on machining performance was investigated by experiments. It was found that the rotating of electrode could move the position of discharge plasma channel, and high pressure flushing could wash melted debris out the discharge gap effectively. Both electrode rotating motion and high pressure flushing are contributed to the improvement of machining efficiency.

  3. Electric Drive for an In-wheel Fractional-slot Axial Flux Machine

    Institute of Scientific and Technical Information of China (English)

    Luigi Alberti; Nicola Bian-chi

    2008-01-01

    This paper describes the electric drive for an in-wheel fractional-slot axial flux machine, designed for achievinga wide flux-weakening operating region.By using a slotted stator with fractional-slot windings and additional coresenclosing end windings,the axial flux machine reaches a wide constant power speed range. The machine is designed forincreasing flux-weakening capability while obtaining low harmonic back-electromotive force and low cogging torque.A 10maximize the output torque in the flux-weakening region, is designed and implemented.The goodness of both design andcontrol algorithm is proved by experimental tests.However,such a fractional-slot machine has not only advantages.Rotorlosses are very high ,and they have to be properly considered during the design process.

  4. Possibilities for Automatic Control of Hydro-Mechanical Transmission and Birotating Electric Machine

    Directory of Open Access Journals (Sweden)

    V. V. Mikhailov

    2014-01-01

    Full Text Available The paper presents mathematical models and results of virtual investigations pertaining to the selected motion parameters of a mobile machine equipped with hydro mechanical and modernized transmissions. The machine has been tested in similar technological cycles and it has been equipped with a universal automatic control system. Changes in structure and type of power transmission have been obtained with the help of a control algorithm including an extra reversible electric machine which is switched in at some operational modes.Implementation of the proposed  concept makes it possible to obtain and check the improved C-code of the control system and enhance operational parameters of the transmission and machine efficiency, reduce slippage and tire wear while using braking energy for its later beneficial use which is usually considered as a consumable element.

  5. Application of new tool material for electrical discharge machining (EDM)

    Indian Academy of Sciences (India)

    A K Khanra; L C Pathak; M M Godkhindi

    2009-08-01

    In EDM, Cu and graphite are commonly used as tool materials. The poor wear resistance is the drawback of these tools. In the current study, an attempt has been made to develop a ZrB2–Cu composite as an EDM tool material to overcome this problem. Initially, the ZrB2 powder is prepared by self-propagating high-temperature synthesis (SHS) technique and synthesized powder is mixed with different amounts of Cu powder. Dense composite is developed by a pressureless sintering at 1250°C. The composites are tested as tool material at different EDM process parameters during machining of mild steel. The ZrB2–40 wt% Cu composite shows highest metal removal rate (MRR) with significant tool removal rate (TRR) than other composites. The performance of ZrB2–40 wt% Cu composite is compared to conventional Cu tool. The composite shows higher MRR with less TRR than Cu tool but it shows more average surface roughness and diameteral overcut than Cu tool.

  6. Implementation of algorithms based on support vector machine (SVM for electric systems: topic review

    Directory of Open Access Journals (Sweden)

    Jefferson Jara Estupiñan

    2016-06-01

    Full Text Available Objective: To perform a review of implementation of algorithms based on support vectore machine applied to electric systems. Method: A paper search is done mainly on Biblio­graphic Indexes (BI and Bibliographic Bases with Selection Committee (BBSC about support vector machine. This work shows a qualitative and/or quan­titative description about advances and applications in the electrical environment, approaching topics such as: electrical market prediction, demand predic­tion, non-technical losses (theft, alternative energy source and transformers, among others, in each work the respective citation is done in order to guarantee the copy right and allow to the reader a dynamic mo­vement between the reading and the cited works. Results: A detailed review is done, focused on the searching of implemented algorithms in electric sys­tems and innovating application areas. Conclusion: Support vector machines have a lot of applications due to their multiple benefits, however in the electric energy area; they have not been tota­lly applied, this allow to identify a promising area of researching.

  7. System and method for smoothing a salient rotor in electrical machines

    Energy Technology Data Exchange (ETDEWEB)

    Raminosoa, Tsarafidy; Alexander, James Pellegrino; El-Refaie, Ayman Mohamed Fawzi; Torrey, David A.

    2016-12-13

    An electrical machine exhibiting reduced friction and windage losses is disclosed. The electrical machine includes a stator and a rotor assembly configured to rotate relative to the stator, wherein the rotor assembly comprises a rotor core including a plurality of salient rotor poles that are spaced apart from one another around an inner hub such that an interpolar gap is formed between each adjacent pair of salient rotor poles, with an opening being defined by the rotor core in each interpolar gap. Electrically non-conductive and non-magnetic inserts are positioned in the gaps formed between the salient rotor poles, with each of the inserts including a mating feature formed an axially inner edge thereof that is configured to mate with a respective opening being defined by the rotor core, so as to secure the insert to the rotor core against centrifugal force experienced during rotation of the rotor assembly.

  8. Measuring drift velocity and electric field in mirror machine by fast photography

    Science.gov (United States)

    Be'ery, I.; Seemann, O.; Fruchtman, A.; Fisher, A.; Nemirovsky, J.

    2013-02-01

    The flute instability in mirror machines is driven by spatial charge accumulation and the resulting E × B plasma drift. On the other hand, E × B drift due to external electrodes or coils can be used as a stabilizing feedback mechanism. Fast photography is used to visualize Hydrogen plasma in a small mirror machine and infer the plasma drift and the internal electric field distribution. Using incompressible flow and monotonic decay assumptions we obtain components of the velocity field from the temporal evolution of the plasma cross section. The electric field perpendicular to the density gradient is then deduced from E=-V × B. With this technique we analyzed the electric field of flute perturbations and the field induced by electrodes immersed in the plasma.

  9. Design and market considerations for axial flux superconducting electric machine design

    Science.gov (United States)

    Ainslie, M. D.; George, A.; Shaw, R.; Dawson, L.; Winfield, A.; Steketee, M.; Stockley, S.

    2014-05-01

    In this paper, the authors investigate a number of design and market considerations for an axial flux superconducting electric machine design that uses high temperature superconductors. The axial flux machine design is assumed to utilise high temperature superconductors in both wire (stator winding) and bulk (rotor field) forms, to operate over a temperature range of 65-77 K, and to have a power output in the range from 10s of kW up to 1 MW (typical for axial flux machines), with approximately 2-3 T as the peak trapped field in the bulk superconductors. The authors firstly investigate the applicability of this type of machine as a generator in small- and medium-sized wind turbines, including the current and forecasted market and pricing for conventional turbines. Next, a study is also carried out on the machine's applicability as an in-wheel hub motor for electric vehicles. Some recommendations for future applications are made based on the outcome of these two studies. Finally, the cost of YBCO-based superconducting (2G HTS) wire is analysed with respect to competing wire technologies and compared with current conventional material costs and current wire costs for both 1G and 2G HTS are still too great to be economically feasible for such superconducting devices.

  10. Algorithm for Modeling Wire Cut Electrical Discharge Machine Parameters using Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    G.Sankara Narayanan

    2014-03-01

    Full Text Available Unconventional machining process finds lot of application in aerospace and precision industries. It is preferred over other conventional methods because of the advent of composite and high strength to weight ratio materials, complex parts and also because of its high accuracy and precision. Usually in unconventional machine tools, trial and error method is used to fix the values of process parameters which increase the production time and material wastage. A mathematical model functionally relating process parameters and operating parameters of a wire cut electric discharge machine (WEDM is developed incorporating Artificial neural network (ANN and the work piece material is SKD11 tool steel. This is accomplished by training a feed forward neural network with back propagation learning Levenberg-Marquardt algorithm. The required data used for training and testing the ANN are obtained by conducting trial runs in wire cut electric discharge machine in a small scale industry from South India. The programs for training and testing the neural network are developed, using matlab 7.0.1 package. In this work, we have considered the parameters such as thickness, time and wear as the input values and from that the values of the process parameters are related and a algorithm is arrived. Hence, the proposed algorithm reduces the time taken by trial runs to set the input process parameters of WEDM and thus reduces the production time along with reduction in material wastage. Thus the cost of machining processes is reduced and thereby increases the overall productivity.

  11. Development of an Electric Motor Powered Low Cost Coconut Deshelling Machine

    Science.gov (United States)

    Mondal, Imdadul Hoque; Prasanna Kumar, G. V.

    2016-06-01

    An electric motor powered coconut deshelling machine was developed in line with the commercially available unit, but with slight modifications. The machine worked on the principle that the coconut shell can be caused to fail in shear and compressive forces. It consisted of a toothed wheel, a deshelling rod, an electric motor, and a compound chain drive. A bevelled 16 teeth sprocket with 18 mm pitch was used as the toothed wheel. Mild steel round bar of 18 mm diameter was used as the deshelling rod. The sharp edge tip of the deshelling rod was inserted below the shell to apply shear force on the shell, and the fruit was tilted toward the rotary toothed wheel to apply the compressive force on the shell. The speed of rotation of the toothed wheel was set at 34 ± 2 rpm. The output capacity of the machine was found to be 24 coconuts/h with 95 % of the total time effectively used for deshelling. The labour requirement was found to be 43 man-h/1000 nuts. About 13 % of the kernels got scraped and about 7 % got sliced during the operation. The developed coconut deshelling machine was recommended for the minimum annual use of 200 h or deshelling of 4700 coconuts per year. The cost of operation for 200 h of annual use was found to be about ` 47/h. The developed machine was found to be simple, easy to operate, energy efficient, safe and reduce drudgery involved in deshelling by conventional methods.

  12. Characteristic evaluation of Al2O3/CNTs hybrid materials for micro-electrical discharge machining

    Institute of Scientific and Technical Information of China (English)

    Hyun-Seok TAK; Chang-Seung HA; Ho-Jun LEE; Hyung-Woo LEE; Young-Keun JEONG; Myung-Chang KANG

    2011-01-01

    The characteristic evaluation of aluminum oxide (Al2O3)/carbon nanotubes (CNTs) hybrid composites for micro-electrical discharge machining (EDM) was described. Alumina matrix composites reinforced with CNTs were fabricated by a catalytic chemical vapor deposition method. Al2O3 composites with different CNT concentrations were synthesized. The electrical characteristic of Al2O3/CNTs composites was examined. These composites were machined by the EDM process according to the various EDM parameters, and the characteristics of machining were analyzed using field emission scanning electron microscope (FESEM). The electrical conductivity has a increasing tendency as the CNTs content is increased and has a critical point at 5% Al2O3 (volume fraction). In the machining accuracy, many tangles of CNT in Al2O3/CNTs composites cause violent spark. Thus, it causes the poor dimensional accuracy and circularity. The results show that conductivity of the materials and homogeneous distribution of CNTs in the matrix are important factors for micro-EDM of Al2O3/CNTs hybrid composites.

  13. Converters and electric machines. Solid insulating materials. Electrical characteristics; Convertisseurs et machines electriques. Materiaux isolants solides. Caracteristiques electriques

    Energy Technology Data Exchange (ETDEWEB)

    Anton, A. [Institut National Superieur de Chimie Industrielle, 76 - Rouen (France)

    2003-08-01

    The aim of this article is to allow a preselection of a solid insulating material using the most common electrical characteristics: tangent of the loss angle, relative permittivity, dielectric rigidity, superficial resistivity, transverse resistivity, resistance to high voltage creeping spark currents, index of creeping resistance. The characteristics of the main solid insulating materials are presented in tables for: thermoplastics, thermosetting materials, natural insulating materials, mineral insulating materials, rubber and synthetic elastomers, stratified insulating materials, thermoplastic films, composite synthetic papers. A comparison is made between the different materials using the three properties: tangent of the loss angle, relative permittivity and resistance to HV spark creeping currents. (J.S.)

  14. General Electric : Immelt surve all / Jena McGregor

    Index Scriptorium Estoniae

    McGregor, Jena

    2008-01-01

    Ettevõtte General Electric juht Jeffrey R. Immelt võitleb selle nimel, et taastada usaldus firma vastu, kuna laenukriis ja kehvad aktsiahinnad on tekitanud olukorra, kus investorid avaldavad suurt survet ettevõtte juhile. Lisa: GE kindralid

  15. General Electric tõrjus Microsofti liidrikohalt / Kaja Koovit

    Index Scriptorium Estoniae

    Koovit, Kaja, 1968-

    2001-01-01

    General Electric võttis Microsofti ees liidrikoha maailma suurima turuväärtusega ettevõtte edetabelis FT500. Tabelid: Maailma suurima turukapitalisatsiooniga ettevõtete TOP25, Skandinaavia firmade turuväärtuse TOP10

  16. General Electric tõrjus Microsofti liidrikohalt / Kaja Koovit

    Index Scriptorium Estoniae

    Koovit, Kaja, 1968-

    2001-01-01

    General Electric võttis Microsofti ees liidrikoha maailma suurima turuväärtusega ettevõtte edetabelis FT500. Tabelid: Maailma suurima turukapitalisatsiooniga ettevõtete TOP25, Skandinaavia firmade turuväärtuse TOP10

  17. General Electric : Immelt surve all / Jena McGregor

    Index Scriptorium Estoniae

    McGregor, Jena

    2008-01-01

    Ettevõtte General Electric juht Jeffrey R. Immelt võitleb selle nimel, et taastada usaldus firma vastu, kuna laenukriis ja kehvad aktsiahinnad on tekitanud olukorra, kus investorid avaldavad suurt survet ettevõtte juhile. Lisa: GE kindralid

  18. General Electric presents $325,000 to College of Engineering

    OpenAIRE

    Nystrom, Lynn A.

    2007-01-01

    The General Electric Company has presented a $300,000 check to Virginia Tech's College of Engineering to create three endowed fellowships in memory of its three slain engineering professors killed on April 16.

  19. General Electric presents $325,000 to College of Engineering

    OpenAIRE

    Nystrom, Lynn A.

    2007-01-01

    The General Electric Company has presented a $300,000 check to Virginia Tech's College of Engineering to create three endowed fellowships in memory of its three slain engineering professors killed on April 16.

  20. The Impact of Additive Manufacturing on the Development of Electrical Machines for MEA Applications: A Feasibility Study

    OpenAIRE

    Garibaldi, Michele; Gerada, Chris; Ashcroft, Ian; Hague, Richard; Morvan, Herve

    2015-01-01

    International audience; This paper discusses the potential of Additive Manufacturing (AM) as an innovative means of manufacturing electrical machines, with particular focus on the benefits for the MEA. It is argued that the unrivalled design freedom offered by AM may revolutionise the way rotating electrical machines are designed and manufactured. Until now the design of standard electrical motors has not gone much beyond the two-dimensions, mainly due to constraints imposed by the manufactur...

  1. Numerical-Analytical Method for Magnetic Field Computation in Rotational Electric Machines

    Institute of Scientific and Technical Information of China (English)

    章跃进; 江建中; 屠关镇

    2003-01-01

    A numerical-analytical method is applied for the two-dimensional magnetic field computation in rotational electric machines in this paper. The analytical expressions for air gap magnetic field axe derived. The pole pairs in the expressions are taken into account so that the solution region can be reduced within one periodic range. The numerical and analytical magnetic field equations are linked with equal vector magnetic potential boundary conditions. The magnetic field of a brushless permanent magnet machine is computed by the proposed method. The result is compared to that obtained by finite element method so as to validate the correction of th method.

  2. An experimental investigation of wire electrical discharge machining of hot-pressed boron carbide

    Directory of Open Access Journals (Sweden)

    Ravindranadh Bobbili

    2015-12-01

    Full Text Available The present work discusses the experimental study on wire-cut electric discharge machining of hot-pressed boron carbide. The effects of machining parameters, such as pulse on time (TON, peak current (IP, flushing pressure (FP and spark voltage on material removal rate (MRR and surface roughness (Ra of the material, have been evaluated. These parameters are found to have an effect on the surface integrity of boron carbide machined samples. Wear rate of brass wire increases with rise in input energy in machining of hot-pressed boron carbide. The surfaces of machined samples were examined using scanning electron microscopy (SEM. The influence of machining parameters on mechanism of MRR and Ra was described. It was demonstrated that higher TON and peak current deteriorate the surface finish of boron carbide samples and result in the formation of large craters, debris and micro cracks. The generation of spherical particles was noticed and it was attributed to surface tension of molten material. Macro-ridges were also observed on the surface due to protrusion of molten material at higher discharge energy levels.

  3. EXPERIMENTAL EVALUATION OF NUMERICAL MODELS TO REPRESENT THE STIFFNESS OF LAMINATED ROTOR CORES IN ELECTRICAL MACHINES

    Directory of Open Access Journals (Sweden)

    HIDERALDO L. V. SANTOS

    2013-08-01

    Full Text Available Usually, electrical machines have a metallic cylinder made up of a compacted stack of thin metal plates (referred as laminated core assembled with an interference fit on the shaft. The laminated structure is required to improve the electrical performance of the machine and, besides adding inertia, also enhances the stiffness of the system. Inadequate characterization of this element may lead to errors when assessing the dynamic behavior of the rotor. The aim of this work was therefore to evaluate three beam models used to represent the laminated core of rotating electrical machines. The following finite element beam models are analyzed: (i an “equivalent diameter model”, (ii an “unbranched model” and (iii a “branched model”. To validate the numerical models, experiments are performed with nine different electrical rotors so that the first non-rotating natural frequencies and corresponding vibration modes in a free-free support condition are obtained experimentally. The models are evaluated by comparing the natural frequencies and corresponding vibration mode shapes obtained experimentally with those obtained numerically. Finally, a critical discussion of the behavior of the beam models studied is presented. The results show that for the majority of the rotors tested, the “branched model” is the most suitable

  4. Scale effects and a method for similarity evaluation in micro electrical discharge machining

    Science.gov (United States)

    Liu, Qingyu; Zhang, Qinhe; Wang, Kan; Zhu, Guang; Fu, Xiuzhuo; Zhang, Jianhua

    2016-08-01

    Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at the micro-scale, which can make it difficult to predict and optimize the machining performances of micro EDM. A new concept of "scale effects" in micro EDM is proposed, the scale effects can reveal the difference in machining performances between micro EDM and conventional macro EDM. Similarity theory is presented to evaluate the scale effects in micro EDM. Single factor experiments are conducted and the experimental results are analyzed by discussing the similarity difference and similarity precision. The results show that the output results of scale effects in micro EDM do not change linearly with discharge parameters. The values of similarity precision of machining time significantly increase when scaling-down the capacitance or open-circuit voltage. It is indicated that the lower the scale of the discharge parameter, the greater the deviation of non-geometrical similarity degree over geometrical similarity degree, which means that the micro EDM system with lower discharge energy experiences more scale effects. The largest similarity difference is 5.34 while the largest similarity precision can be as high as 114.03. It is suggested that the similarity precision is more effective in reflecting the scale effects and their fluctuation than similarity difference. Consequently, similarity theory is suitable for evaluating the scale effects in micro EDM. This proposed research offers engineering values for optimizing the machining parameters and improving the machining performances of micro EDM.

  5. Study of the machining process of nano-electrical discharge machining based on combined atomistic-continuum modeling method

    Science.gov (United States)

    Zhang, Guojun; Guo, Jianwen; Ming, Wuyi; Huang, Yu; Shao, Xinyu; Zhang, Zhen

    2014-01-01

    Nano-electrical discharge machining (nano-EDM) is an attractive measure to manufacture parts with nanoscale precision, however, due to the incompleteness of its theories, the development of more advanced nano-EDM technology is impeded. In this paper, a computational simulation model combining the molecular dynamics simulation model and the two-temperature model for single discharge process in nano-EDM is constructed to study the machining mechanism of nano-EDM from the thermal point of view. The melting process is analyzed. Before the heated material gets melted, thermal compressive stress higher than 3 GPa is induced. After the material gets melted, the compressive stress gets relieved. The cooling and solidifying processes are also analyzed. It is found that during the cooling process of the melted material, tensile stress higher than 3 GPa arises, which leads to the disintegration of material. The formation of the white layer is attributed to the homogeneous solidification, and additionally, the resultant residual stress is analyzed.

  6. Effect of Carbon in the Dielectric Fluid and Workpieces on the Characteristics of Recast Layers Machined by Electrical Discharge Machining

    Science.gov (United States)

    Muttamara, Apiwat; Kanchanomai, Chaosuan

    2016-06-01

    Electrical discharge machining (EDM) is a popular non-traditional machining technique that is usually performed in kerosene. Carbon from the kerosene is mixed into the recast layer during EDM, increasing its hardness. EDM can be performed in deionized water, which causes decarburization. We studied the effects of carbon in the dielectric fluid and workpiece on the characteristics of recast layers. Experiments were conducted using gray cast iron and mild steel workpieces in deionized water or kerosene under identical operating conditions. Scanning electron microscopy revealed that the recast layer formed on gray iron was rougher than that produced on mild steel. Moreover, the dispersion of graphite flakes in the gray iron seemed to cause subsurface cracks, even when EDM was performed in deionized water. Dendritic structures and iron carbides were found in the recast layer of gray iron treated in deionized water. Kerosene caused more microcracks to form and increased surface roughness compared with deionized water. The microcrack length per unit area of mild steel treated in deionized water was greater than that treated in kerosene, but the cracks formed in kerosene were wider. The effect of the diffusion of carbon during cooling on the characteristics of the recast layer was discussed.

  7. Modeling of thermal spalling during electrical discharge machining of titanium diboride

    Energy Technology Data Exchange (ETDEWEB)

    Gadalla, A.M.; Bozkurt, B.; Faulk, N.M. (Texas A and M Univ., Dept. of Chemical Engineering, College Station, TX (US))

    1991-04-01

    Erosion in electrical discharge machining has been described as occurring by melting and flushing the liquid formed. Recently, however, thermal spalling was reported as the mechanism for machining refractory materials with low thermal conductivity and high thermal expansion. The process is described in this paper by a model based on a ceramic surface exposed to a constant circular heating source which supplied a constant flux over the pulse duration. The calculations were based on TiB{sub 2} mechanical properties along a and c directions. Theoretical predictions were verified by machining hexagonal TiB{sub 2}. Large flakes of TiB{sub 2} with sizes close to grain size and maximum thickness close to the predicted values were collected, together with spherical particles of Cu and Zn eroded from cutting wire. The cutting surfaces consist of cleavage planes sometimes contaminated with Cu, Zn, and impurities from the dielectric fluid.

  8. Electrode Wear Prediction in Milling Electrical Discharge Machining Based on Radial Basis Function Neural Network

    Institute of Scientific and Technical Information of China (English)

    HUANG He; BAI Ji-cheng; LU Ze-sheng; GUO Yong-feng

    2009-01-01

    Milling electrical discharge machining (EDM) enables the machining of complex cavities using cylindrical or tubular electrodes. To ensure acceptable machining accuracy the process requires some methods of compensating for electrode wear. Due to the complexity and random nature of the process, existing methods of compensating for such wear usually involve off-line prediction. This paper discusses an innovative model of electrode wear prediction for milling EDM based upon a radial basis function (RBF) network. Data gained from an orthogonal experiment were used to provide training samples for the RBF network. The model established was used to forecast the electrode wear, making it possible to calculate the real-time tool wear in the milling EDM process and, to lay the foundations for dynamic compensation of the electrode wear on-line. This paper demonstrates that by using this model prediction errors can be controlled within 8%.

  9. Electric vehicle state of charge estimation: Nonlinear correlation and fuzzy support vector machine

    Science.gov (United States)

    Sheng, Hanmin; Xiao, Jian

    2015-05-01

    The aim of this study is to estimate the state of charge (SOC) of the lithium iron phosphate (LiFePO4) battery pack by applying machine learning strategy. To reduce the noise sensitive issue of common machine learning strategies, a kind of SOC estimation method based on fuzzy least square support vector machine is proposed. By applying fuzzy inference and nonlinear correlation measurement, the effects of the samples with low confidence can be reduced. Further, a new approach for determining the error interval of regression results is proposed to avoid the control system malfunction. Tests are carried out on modified COMS electric vehicles, with two battery packs each consists of 24 50 Ah LiFePO4 batteries. The effectiveness of the method is proven by the test and the comparison with other popular methods.

  10. Using financial risk measures for analyzing generalization performance of machine learning models.

    Science.gov (United States)

    Takeda, Akiko; Kanamori, Takafumi

    2014-09-01

    We propose a unified machine learning model (UMLM) for two-class classification, regression and outlier (or novelty) detection via a robust optimization approach. The model embraces various machine learning models such as support vector machine-based and minimax probability machine-based classification and regression models. The unified framework makes it possible to compare and contrast existing learning models and to explain their differences and similarities. In this paper, after relating existing learning models to UMLM, we show some theoretical properties for UMLM. Concretely, we show an interpretation of UMLM as minimizing a well-known financial risk measure (worst-case value-at risk (VaR) or conditional VaR), derive generalization bounds for UMLM using such a risk measure, and prove that solving problems of UMLM leads to estimators with the minimized generalization bounds. Those theoretical properties are applicable to related existing learning models.

  11. High-temperature superconductors in electrical machines and generators in particular; Hochtemperatur-Supraleiter in elektrischen Maschinen, insbesondere Generatoren

    Energy Technology Data Exchange (ETDEWEB)

    Joho, R. [Alstom (Schweiz) AG, Birr (Switzerland)

    2005-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) presents the results of a study that looked at the advantages and disadvantages of large electrical machines with superconductor windings. The study, which was divided into three phases, first made a survey of other current projects, continued to define a benchmark for the current state of the market and, finally, defined an 'action plan' that lists various possibilities for the continuation of the project. High-temperature superconductor technology is described and its application in electrical machines is discussed. Examples are given of electrical machines that use superconductor technology.

  12. An overview of technology and research in electrode design and manufacturing in sinking electrical discharge machining

    Directory of Open Access Journals (Sweden)

    Bhola Jha

    2014-06-01

    Full Text Available Electrical discharge machining (EDM is one of the earliest non-traditional machining processes, based on thermoelectric energy between the workpiece and an electrode. In this process, the material is removed electro thermally by a series of successive discrete discharges between two electrically conductive objects, i.e., the electrode and the workpiece. The performance of the process, to a large extent, depends on the material, design and manufacturing method of the electrodes. Electrode design and method of its manufacturing also affect on the cost of electrode. Researchers have explored a number of ways to improve electrode design and devised various ways of manufacturing. The paper reports a review on the research relating to EDM electrode design and its manufacturing for improving and optimizing performance measures and reducing time and cost of manufacturing. The final part of the paper discusses these developments and outlines the trends for future research work.

  13. Condition Assessment and End-of-Life Prediction System for Electric Machines and Their Loads

    Science.gov (United States)

    Parlos, Alexander G.; Toliyat, Hamid A.

    2005-01-01

    An end-of-life prediction system developed for electric machines and their loads could be used in integrated vehicle health monitoring at NASA and in other government agencies. This system will provide on-line, real-time condition assessment and end-of-life prediction of electric machines (e.g., motors, generators) and/or their loads of mechanically coupled machinery (e.g., pumps, fans, compressors, turbines, conveyor belts, magnetic levitation trains, and others). In long-duration space flight, the ability to predict the lifetime of machinery could spell the difference between mission success or failure. Therefore, the system described here may be of inestimable value to the U.S. space program. The system will provide continuous monitoring for on-line condition assessment and end-of-life prediction as opposed to the current off-line diagnoses.

  14. Surface performance of workpieces processed by electrical discharge machining in gas

    Institute of Scientific and Technical Information of China (English)

    LI Li-qing; BAI Ji-cheng; GUO Yong-feng; WANG Zhen-long

    2009-01-01

    The surface performance of workpieces processed by electrical discharge machining in gas (dry EDM) was studied in this paper. Firstly, the composition, micro hardness and recast layer of electrical discharge machined (EDMed) surface of 45 carbon steels in air were investigated through different test analysis methods. The results show that the workpiece surface EDMed in air contains a certain quantity of oxide, and oxidation occurs on the workpiece surface. Compared with the surface of workpieces processed in kerosene, fewer cracks exist on the dry EDMed workpiece surface, and the surface recast layer is thinner than that obtained by conventional EDM. The micro hardness of workpieces machined by dry EDM method is lower than that machined in kerosene, and higher than that of the matrix. In addition, experiments were conducted on the surface wear resistance of workpieces processed in air and kerosene using copper electrode and titanium alloy electrode.The results indicate that the surface wear resistance of workpieces processed in air can be improved, and it is related with tool material and dielectric.

  15. Effect of electric discharge machining on the fatigue life of Inconel 718

    Science.gov (United States)

    Jeelani, S.; Collins, M. R.

    1988-01-01

    The effect of electric discharge machining on the fatigue life of Inconel 718 alloy at room temperature was investigated. Data were generated in the uniaxial tension fatigue mode at ambient temperature using flat 3.175 mm thick specimens. The specimens were machined on a wire-cut electric discharge machine at cutting speeds ranging from 0.5 to 2 mm per minute. The specimens were fatigued at a selected stress, and the resulting fatigue lives compared with that of the virgin material. The surfaces of the fatigued specimens were examined under optical and scanning electron microscopes, and the roughness of the surfaces was measured using a standard profilometer. From the results of the investigation, it was concluded that the fatigue life of the specimens machined using EDM decreased slightly as compared with that of the virgin material, but remained unchanged as the cutting speed was changed. The results are explained using data produced employing microhardness measurements, profilometry, and optical and scanning microscopy.

  16. SIMULATION SYSTEM FOR FIVE-AXIS NC MACHINING USING GENERAL CUTTING TOOL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A simulation system for five-axis NC machining using general cutting tools is presented. This system differs from other simulation system in that it not only focuses on the geometric simulation but also focuses on the collision detection which is usually not included in NC machining simulation. Besides all of these, estimating cutting forces is also discussed. In order to obtain high efficiency, all algorithms use swept volume modeling technique, so the simulation system is compact and can be performed efficiently.

  17. Generalized sensitivity evaluation of electrical power systems

    Energy Technology Data Exchange (ETDEWEB)

    Grewal, H.K.

    1987-01-01

    The material presented in this thesis is a logical extension of and addition to previous work on network sensitivities as applied to power-system analysis and planning. The continuing tendency of supplementing the existing extra-high voltage a.c. transmission systems with high-voltage d.c. (HVDC) lines was taken into consideration, and various relevant component models were investigated using a new hybrid network formulation based on the methodology developed by Bandler and El-Kady. The load buses, frequently modeled as PQ buses at which both the real and reactive injected powers are known, and the generator buses characterized by a constant voltage magnitude and constant real injected power, have been dealt with by exploiting a special complex conjugate notation. In addition, the current, voltage and/or power relationships associated with the transmission network branches were investigated. A hybrid formulation for generalized power system component models were developed. This novel formulation not only encompasses the work established on the basis of one-port theory, but it is also capable of manipulating multiport, nonreciprocal, a.c. as well as integrated a.c.-d.c. bulk transmission networks.

  18. Electrical Drive Radiated Emissions Estimation in Terms of Input Control Using Extreme Learning Machines

    Directory of Open Access Journals (Sweden)

    A. Wefky

    2012-01-01

    Full Text Available With the increase of electrical/electronic equipment integration complexity, the electromagnetic compatibility (EMC becomes one of the key points to be respected in order to meet the constructor standard conformity. Electrical drives are known sources of electromagnetic interferences due to the motor as well as the related power electronics. They are the principal radiated emissions source in automotive applications. This paper shows that there is a direct relationship between the input control voltage and the corresponding level of radiated emissions. It also introduces a novel model using artificial intelligence techniques for estimating the radiated emissions of a DC-motor-based electrical drive in terms of its input voltage. Details of the training and testing of the developed extreme learning machine (ELM are described. Good agreement between the electrical drive behavior and the developed model is observed.

  19. Rapid and Efficient Synthesis of Silver Nanofluid Using Electrical Discharge Machining

    OpenAIRE

    Kuo-Hsiung Tseng; Heng-Lin Lee; Chih-Yu Liao; Kuan-Chih Chen; Hong-Shiou Lin

    2013-01-01

    The electrical discharge machining (EDM) system has been proven feasible as a rapid and efficient method for silver nanofluid preparation. This study prepared the silver nano-fluid via EDM and investigated the relationship between its process parameters and product characteristics. The prior study had found that the silver nano-fluid prepared by EDM contained both silver nanoparticles and silver ions. Silver ions had revealed the cause of the high suspension of the silver nanoparticles. To ex...

  20. Research on Modeling and Control of Regenerative Braking for Brushless DC Machines Driven Electric Vehicles

    OpenAIRE

    Jian-ping Wen; Chuan-wei Zhang

    2015-01-01

    In order to improve energy utilization rate of battery-powered electric vehicle (EV) using brushless DC machine (BLDCM), the model of braking current generated by regenerative braking and control method are discussed. On the basis of the equivalent circuit of BLDCM during the generative braking period, the mathematic model of braking current is established. By using an extended state observer (ESO) to observe actual braking current and the unknown disturbances of regenerative braking system, ...

  1. Electrical Discharge Machining Flyback Converter using UC3842 Current Mode PWM Controller

    Directory of Open Access Journals (Sweden)

    Nazriah Mahmud

    2014-10-01

    Full Text Available This paper presents a current mode Pulse Width Modulation (PWM controlled Flyback converter using UC3842 for Electrical Discharge Machining current generator control circuit. Circuit simplicity and high efficiency can be achieved by a Flyback converter with current mode PWM controller. The behaviors of the system's operation is analyzed and discussed by varying the load resistance. Matlab sofware is used to simulate the Flyback converter where a prototype has been built and tested to verify it's performance.

  2. Magnetic field analysis of electric machines taking ferromagnetic hysteresis into account

    OpenAIRE

    Saitz, Július

    2001-01-01

    This thesis deals with the magnetic field analysis of electric machines by means of the finite element method taking the ferromagnetic hysteresis into account. The hysteresis is considered through a vector Preisach model, consisting of scalar Preisach models distributed along a finite number of angular directions. The incorporation of the vector hysteresis model into a two-dimensional time-stepping field solution in terms of the magnetic vector potential is accomplished by the Fixed-Point ite...

  3. EXPERIMENTAL INVESTIGATION ON ELECTRICAL DISCHARGE MACHINING OF TITANIUM ALLOY USING COPPER, BRASS AND ALUMINUM ELECTRODES

    Directory of Open Access Journals (Sweden)

    S. DHANABALAN

    2015-01-01

    Full Text Available In the present study, an evaluation has been done on Material Removal Rate (MRR, Surface Roughness (SR and Electrode Wear Rate (EWR during Electrical Discharge Machining (EDM of titanium alloy using copper, brass and aluminum electrodes. Analyzing previous work in this field, it is found that electrode wear and material removal rate increases with an increase current. It is also found that the electrode wear ratio increases with an increase in current. The higher wear ratio is found during machining of titanium alloy using a brass electrode. An attempt has been made to correlate the thermal conductivity and melting point of electrode with the MRR and electrode wear. The MRR is found to be high while machining titanium alloy using brass electrode. During machining of titanium alloy using copper electrodes, a comparatively smaller quantity of heat is absorbed by the work material due to low thermal conductivity. Due to the above reason, the MRR becomes very low. Duringmachining of titanium alloy using aluminium electrodes, the material removal rate and electrode wear rate are only average value while machining of titanium alloy using brass and copper electrodes.

  4. Basic concepts, status, opportunities, and challenges of electrical machines utilizing high-temperature superconducting (HTS) windings

    Energy Technology Data Exchange (ETDEWEB)

    Frauenhofer, J [Siemens AG, Automation and Drives, Large Drives (Germany); Grundmann, J; Klaus, G; Nick, W [Siemens AG, Corporate Technology, PO Box 3220, 91050 Erlangen (Germany)], E-mail: wolfgang.nick@siemens.com

    2008-02-15

    An overview of the different approaches towards achieving a marketable application of a superconducting electrical machine, either as synchronous motor or generator, will be given. This field ranges from relatively small industrial drives to utility generators with large power ratings, from the low speed and high torque of wind power generators and ship propulsion motors, to high speed generators attached to turbines. Essentially HTS machine technology offers several advantages such as compactness (weight and volume reduction), increased efficiency, and other operational benefits. The machine features have to be optimized with regard to the specific application, and different concepts were developed by internationally competing teams, with Siemens being one of them. The achieved status in these fields will be summarized, pointing to the specific technical challenges to overcome. For this purpose we have not only to consider the technology of manufacturing the HTS rotor winding itself, but also to check requirements and availability of supporting technologies. This ranges from new challenges posed to the non-superconducting ('conventional') components of such innovative HTS machines, manufacturing superconducting material in the coming transition from 1st to 2nd generation HTS tape, cryogenic technology including material behavior, to new and challenging tasks in simulating and predicting the performance of such machines by computational tools. The question of market opportunities for this technology obviously is a function of all these aspects; however, a strong tendency for the near future is seen in the area of high-torque ship propulsion.

  5. Basic concepts, status, opportunities, and challenges of electrical machines utilizing high-temperature superconducting (HTS) windings

    Science.gov (United States)

    Frauenhofer, J.; Grundmann, J.; Klaus, G.; Nick, W.

    2008-02-01

    An overview of the different approaches towards achieving a marketable application of a superconducting electrical machine, either as synchronous motor or generator, will be given. This field ranges from relatively small industrial drives to utility generators with large power ratings, from the low speed and high torque of wind power generators and ship propulsion motors, to high speed generators attached to turbines. Essentially HTS machine technology offers several advantages such as compactness (weight and volume reduction), increased efficiency, and other operational benefits. The machine features have to be optimized with regard to the specific application, and different concepts were developed by internationally competing teams, with Siemens being one of them. The achieved status in these fields will be summarized, pointing to the specific technical challenges to overcome. For this purpose we have not only to consider the technology of manufacturing the HTS rotor winding itself, but also to check requirements and availability of supporting technologies. This ranges from new challenges posed to the non-superconducting ("conventional") components of such innovative HTS machines, manufacturing superconducting material in the coming transition from 1st to 2nd generation HTS tape, cryogenic technology including material behavior, to new and challenging tasks in simulating and predicting the performance of such machines by computational tools. The question of market opportunities for this technology obviously is a function of all these aspects; however, a strong tendency for the near future is seen in the area of high-torque ship propulsion.

  6. Experimental study of surface roughness in Electric Discharge Machining (EDM based on Grey Relational Analysis

    Directory of Open Access Journals (Sweden)

    Mat Deris Ashanira

    2016-01-01

    Full Text Available Electric Discharge Machining (EDM is one of the modern machining which is capable in handling hard and difficult-to-machine material. The successful of EDM basically depends on its performances such as surface roughness (Ra, material removal rate (MRR, electrode wear rate (EWR and dimensional accuracy (DA. Ra is considered as the most important performance due to it role as a technological quality measurement for a product and also a factor that significantly affects the manufacturing process. This paper presents the experimental study of surface roughness in die sinking EDM using stainless steel SS316L with copper impregnated graphite electrode. The machining experimental is conducted based on the two levels full factorial design of design of experiment (DOE with five machining parameters which are peak current, servo voltage, servo speed, pulse on time and pulse off time. The results were analyzed using grey relational analysis (GRA and it was found that pulse on time and servo voltage give the most influence to the Ra value.

  7. Heat production in the windings of the stators of electric machines under stationary condition

    Science.gov (United States)

    Alebouyeh Samami, Behzad; Pieper, Martin; Breitbach, Gerd; Hodapp, Josef

    2014-12-01

    In electric machines due to high currents and resistive losses (joule heating) heat is produced. To avoid damages by overheating the design of effective cooling systems is required. Therefore the knowledge of heat sources and heat transfer processes is necessary. The purpose of this paper is to illustrate a good and effective calculation method for the temperature analysis based on homogenization techniques. These methods have been applied for the stator windings in a slot of an electric machine consisting of copper wires and resin. The key quantity here is an effective thermal conductivity, which characterizes the heterogeneous wire resin-arrangement inside the stator slot. To illustrate the applicability of the method, the analysis of a simplified, homogenized model is compared with the detailed analysis of temperature behavior inside a slot of an electric machine according to the heat generation. We considered here only the stationary situation. The achieved numerical results are accurate and show that the applied homogenization technique works in practice. Finally the results of simulations for the two cases, the original model of the slot and the homogenized model chosen for the slot (unit cell), are compared to experimental results.

  8. Parametric Investigation of Powder Mixed Electrical Discharge Machining of Al-Sic Metal Matrix Composites

    Directory of Open Access Journals (Sweden)

    R. K. Arya

    2012-12-01

    Full Text Available Abstract – In recent few years composite materials have gained pace in engineering application. But they have poor machinability by using conventional machining methods. So it is required to study about these materials for better use in engineering application. To fulfillment of this aim, a study is done by conduct experiments (i.e. Machining on Al/SiC metal matrix composite (MMC. From the non-conventional machining process, Powder Mixed Electrical discharge machining (PMEDM is used to machining of Al/SiC MMC. PMEDM is a technological improvement in conventional EDM, which was previously studied by many researchers to better MRR with good surface roughness (SR. In this study, the controllable machining process parameters (i.e. Peak Current (Ip, Duty Cycle, Powder Concentration (PC, Gap Control and Sensitivity of PMEDM was selected to experimental investigation. The process performance is measured in terms of material removal rate (MRR and surface finish (SR. The research outcome will identify the important parameters and their effect on MRR of Al/SiC MMC in the presence of suspended graphite (Gr powder in a kerosene dielectric of EDM. Response surface methodology (RSM has been used to plan and analyze the experimental results. The experimental results emerged that only sensitivity has non-significant effect on MMR and SR from the selected process parameters, but it gives significant effects with other factors in interaction. Further it found that, the MRR is directly proportional to Ip and inversely proportional to the PC and duty cycle, and the SR improves at lower Ip and optimum range of PC, gap control and duty cycle.

  9. Rotating electrical machines, pt.2: Methods for determining losses and efficiency of rotating electrical machinery form tests (excl. machines for traction vehicles), 1st suppl. Measurement of losses by the calorimetric method

    CERN Document Server

    International Electrotechnical Commission. Geneva

    1974-01-01

    Describes methods for measuring the efficiency of electrical rotating machines either by determining total losses on load or by determination of the segregated losses for air and water cooling mediums. Applies to large generators but may be used for other machines.

  10. Study for the electric arc of alternative current at the single phase welding machine using the Matlab/Simulink environment

    Science.gov (United States)

    Baciu, I.; Ghiormez, L.; Vasar, C.

    2017-01-01

    In this paper is presented a mathematical model of the electric arc for an alternative current welding machine of low power. The electric arc model is based on dividing the voltage-current characteristic of the electric arc in many functioning zones. For the model of the entire welding machine are used real parameters as the ones of the proper welding machine. The voltage and current harmonics spectrum that is obtained during the welding process is presented. Also, the waveforms for the current and voltage of the electric arc plotted against time and the voltage-current characteristic of the electric arc are illustrated. The electric arc is considered as being supplied by alternative voltage from the electrical power network using a single phase transformer which has the output voltage of 80 volts. The model of the welding machine is developed in Simulink and the variations of some parameters of the electric arc are obtained by modifying of them in a Matlab function. Also, in this paper is presented the total harmonic distortion for the voltage and current of the electric arc obtained during simulation of the welding machine.

  11. DOE FreedomCAR and vehicle technologies program advanced power electronic and electrical machines annual review report

    Energy Technology Data Exchange (ETDEWEB)

    Olszewski, Mitch [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2006-10-11

    This report is a summary of the Review Panel at the FY06 DOE FreedomCAR and Vehicle Technologies (FCVT) Annual Review of Advanced Power Electronics and Electric Machine (APEEM) research activities held on August 15-17, 2006.

  12. Response surface modelling of tool electrode wear rate and material removal rate in micro electrical discharge machining of Inconel 718

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2017-01-01

    conductivity and high strength causing it extremely difficult tomachine. Micro-Electrical Discharge Machining (Micro-EDM) is a non-conventional method that has a potential toovercome these restrictions for machining of Inconel 718. Response Surface Method (RSM) was used for modelling thetool Electrode Wear...

  13. A general purpose subroutine for fast fourier transform on a distributed memory parallel machine

    Science.gov (United States)

    Dubey, A.; Zubair, M.; Grosch, C. E.

    1992-01-01

    One issue which is central in developing a general purpose Fast Fourier Transform (FFT) subroutine on a distributed memory parallel machine is the data distribution. It is possible that different users would like to use the FFT routine with different data distributions. Thus, there is a need to design FFT schemes on distributed memory parallel machines which can support a variety of data distributions. An FFT implementation on a distributed memory parallel machine which works for a number of data distributions commonly encountered in scientific applications is presented. The problem of rearranging the data after computing the FFT is also addressed. The performance of the implementation on a distributed memory parallel machine Intel iPSC/860 is evaluated.

  14. Annual Electric Load Forecasting by a Least Squares Support Vector Machine with a Fruit Fly Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Bao Wang

    2012-11-01

    Full Text Available The accuracy of annual electric load forecasting plays an important role in the economic and social benefits of electric power systems. The least squares support vector machine (LSSVM has been proven to offer strong potential in forecasting issues, particularly by employing an appropriate meta-heuristic algorithm to determine the values of its two parameters. However, these meta-heuristic algorithms have the drawbacks of being hard to understand and reaching the global optimal solution slowly. As a novel meta-heuristic and evolutionary algorithm, the fruit fly optimization algorithm (FOA has the advantages of being easy to understand and fast convergence to the global optimal solution. Therefore, to improve the forecasting performance, this paper proposes a LSSVM-based annual electric load forecasting model that uses FOA to automatically determine the appropriate values of the two parameters for the LSSVM model. By taking the annual electricity consumption of China as an instance, the computational result shows that the LSSVM combined with FOA (LSSVM-FOA outperforms other alternative methods, namely single LSSVM, LSSVM combined with coupled simulated annealing algorithm (LSSVM-CSA, generalized regression neural network (GRNN and regression model.

  15. Mathematic model of three-phase induction machine connected to advanced inverter for traction system for electric trolley

    Directory of Open Access Journals (Sweden)

    LIVIU S. BOCÎI

    2013-06-01

    Full Text Available This paper establishes a mathematical model of induction machine connected to a frequency inverter necessary to adjust the electric motor drive. The mathematical model based on the Park's theory allows the analysis of the whole spectrum (electric car – frequency inverter to drive the electric trolley bus made on ASTRA Bus Arad (Romania. To remove higher order harmonics, the PWM waveform of supply voltage is used, set in the general case. Operating characteristics of electric motor drive are set to sub-nominal frequency (f Bele 2007.Este documento estabelece um modelo matemático de máquina de indução conectado a um inversor de frequência necessário para ajustar o motor de acionamento elétrico. O modelo matemático baseado na Teoria de Park permite a análise de todo o espectro (carro elétrico com inversor de frequência para dirigir o ônibus elétrico feito em ASTRA Bus Arad (Romênia. Para remover harmônicas de ordem mais alta, a forma de onda da tensão de alimentação PWM é utilizado, definido no caso geral. Características de funcionamento do motor de acionamento elétrico são definidas para frequência sub-nominal (f

  16. A control system for and a method of controlling a superconductive rotating electrical machine

    DEFF Research Database (Denmark)

    2014-01-01

    This invention relates to a method of controlling and a control system (100) for a superconductive rotating electric machine (200) comprising at least one superconductive winding (102; 103), where the control system (100) is adapted to control a power unit (101) supplying during use the at least...... one superconductive winding (102; 103) with power or receiving during use power from the at least one superconductive winding (102; 103), wherein the control system (100) is further adapted to, for at least one superconductive winding (102; 103), dynamically receive one or more representations of one...... superconductive winding (102; 103) by the power unit (101) where the one or more electrical current values is/are derived taking into account the received one or more actual values (110, 111). In this way,greater flexibility and more precise control of the performance of the superconducting rotating electrical...

  17. Research of the possibility of using an electrical discharge machining metal powder in selective laser melting

    Science.gov (United States)

    Golubeva, A. A.; Sotov, A. V.; Agapovichev, A. V.; Smelov, V. G.; Dmitriev, V. N.

    2017-02-01

    In this paper the research of a Ni-20Cr-10Fe-3Ti (heat-resistant) alloy metal powder conducted for use in a selective laser melting technology. This metal powder is the slime after electric discharge machining. The technology of cleaning and melting the powder discussed in this article. As a control input of the powder, immediately before 3D printing, dimensional analysis, surface morphology and the internal structure of the powder particles after the treatment were examined using optical and electron microscopes. The powder granules are round, oval, of different diameters with non-metallic inclusions. The internal structure of the particles is solid with no apparent defects. The content of the required diameter of the total volume of test powder granules was 15%. X-ray fluorescence analysis of the powder materials carried out. The possibility of powder melting was investigated in the selective laser melting machine ‘SLM 280HL’. A selection of the melting modes based on the physical properties of the Ni-20Cr-10Fe-3Ti alloy, data obtained from similar studies and a mathematical model of the process. Conclusions on the further investigation of the possibility of using electric discharge machining slime were made.

  18. PARAMETRIC STUDY OF ELECTRICAL DISCHARGE MACHINING OF AISI 304 STAINLESS STEEL

    Directory of Open Access Journals (Sweden)

    P. SRINIVASA RAO,

    2010-08-01

    Full Text Available Electrical discharge machining (EDM is widely used process in the production of mould / dies, aerospace, automobile and electronics industries where intricate complex shapes need to be machined in very hard materials. The selection of the AISI 304 stainless steel was made taking into account its use in almost all industrial applicationsfor approximately 50% of the world’s stainless steel production and consumption. In this work, a study has been carried out on the influence of four design factors: current, open-circuit voltage, servo and dutycycle over material removal rate, tool wear rate, surface roughness and hardness on the die-sinking electrical discharge machining of AISI 304 stainless steel. This has been done using design of experiments (DOE, which allows us to carry out theabove-mentioned analysis performing a relatively small number of experiments. In this case, a 3*24-1 mixed level factorial design, whose resolution is V, has been selected due to the number of factors considered in the study. The resolution of this mixed factorial design allows us to estimate all the main effects, two-factor interactions and pure quadratic effects of the four design factors selected to perform this study.

  19. Analysis of the effect of ultrasonic vibrations on the performance of micro-electrical discharge machining of A2 tool steel

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2016-01-01

    The application of ultrasonic vibrations to a workpiece or tool is a novel hybrid approach in micro-electrical discharge machining. The advantages of this method include effective flushing out of debris, higher machining efficiency and lesser short-circuits during machining. This paper presents...... effective at higher machining depths for achieving stable machining conditions. Regression equations were developed for MRR and TWR with capacitance, ultrasonic vibration factor, feed rate and machining time....

  20. Electric Machine Analysis, Control and Verification for Mechatronics Motion Control Applications, Using New MATLAB Built-in Function and Simulink Model

    Directory of Open Access Journals (Sweden)

    Farhan A. Salem

    2014-05-01

    Full Text Available This paper proposes a new, simple and user–friendly MATLAB built-in function, mathematical and Simulink models, to be used to early identify system level problems, to ensure that all design requirements are met, and, generally, to simplify Mechatronics motion control design process including; performance analysis and verification of a given electric DC machine, proper controller selection and verification for desired output speed or angle.

  1. Modeling and optimization of Electrical Discharge Machining (EDM using statistical design

    Directory of Open Access Journals (Sweden)

    Hegab Husein A.

    2015-01-01

    Full Text Available Modeling and optimization of nontraditional machining is still an ongoing area of research. The objective of this work is to optimize Electrical Discharge Machining process parameters of Aluminum-multiwall carbon Nanotube composites (AL-CNT model. Material Removal Rate (MRR, Wear Electrode Ratio (EWR and Average Surface Roughness (Ra are primary objectives. The Machining parameters are machining-on time (sec, discharge current (A, voltage (V, total depth of cut (mm, and %wt. CNT added. Mathematical models for all responses as function of significant process parameters are developed using Response Surface Methodology (RSM. Experimental results show optimum levels for material removal rate are %wt. CNT (0%, high level of discharge current (6A and low level of voltage (50 V while optimum levels for Electrode wear ratio are %wt. CNT (5%, high level of discharge current (6A and optimum levels for average surface roughness are %wt. CNT (0%, low level of discharge current (2A and high level of depth of cut (1 mm. Single-objective optimization is formulated and solved via Genetic Algorithm. Multi-objective optimization model is then formulated for the three responses of interest. This methodology gathers experimental results, builds mathematical models in the domain of interest and optimizes the process models. As such, process analysis, modeling, design and optimization are achieved.

  2. Design and market considerations for axial flux superconducting electric machine design

    CERN Document Server

    Ainslie, Mark D; Shaw, Robert; Dawson, Lewis; Winfield, Andy; Steketee, Marina; Stockley, Simon

    2013-01-01

    In this paper, the authors investigate a number of design and market considerations for an axial flux superconducting electric machine design that uses high temperature superconductors. This work was carried out as part of the University of Cambridge's Centre for Entrepreneurial Learning ETECH Project programme, designed to accelerate entrepreneurship and diffusion of innovations based on early stage and potentially disruptive technologies from the University. The axial flux machine design is assumed to utilise high temperature superconductors in both wire (stator winding) and bulk (rotor field) forms, to operate over a temperature range of 65-77 K, and to have a power output in the range from 10s of kW up to 1 MW (typical for axial flux machines), with approximately 2-3 T as the peak trapped field in the bulk superconductors. The authors firstly investigate the applicability of this type of machine as a generator in small- and medium-sized wind turbines, including the current and forecasted market and pricin...

  3. Fuzzy-stochastic functor machine for general humanoid-robot dynamics.

    Science.gov (United States)

    Ivancevic, V G; Snoswell, M

    2001-01-01

    In this paper the fuzzy-stochastic-Hamiltonian functor-machine is proposed as a general model for the humanoid-robot dynamics, including all necessary degrees of freedom to match the "realistic" human-like motion. Starting with the continual-sequential generalization of the standard state equation for the linear MIMO-systems, the "meta-cybernetic" model of the "functor-machine" is developed as a three-stage nonlinear description of humanoid dynamics: (1) dissipative, muscle-driven Hamiltonian dynamics, (2) stochastic fluctuations and discrete jumps, and (3) fuzzy inputs, parameters and initial conditions. An example of symmetrical three-dimensional (3-D) load-lifting is used to illustrate all the phases in developing the functor-machine model.

  4. The birth of the electric machines: a commentary on Faraday (1832) 'Experimental researches in electricity'.

    Science.gov (United States)

    Al-Khalili, Jim

    2015-04-13

    The history of science is filled with examples of key discoveries and breakthroughs that have been published as landmark texts or journal papers, and to which one can trace the origins of whole disciplines. Such paradigm-shifting publications include Copernicus' De revolutionibus orbium coelestium (1543), Isaac Newton's Philosophiæ Naturalis Principia Mathematica (1687) and Albert Einstein's papers on relativity (1905 and 1915). Michael Faraday's 1832 paper on electromagnetic induction sits proudly among these works and in a sense can be regarded as having an almost immediate effect in transforming our world in a very real sense more than any of the others listed. Here we review the status of the subject-the relationship between magnetism and electricity both before and after Faraday's paper and delve into the details of the key experiments he carried out at the Royal Institution outlining clearly how he discovered the process of electromagnetic induction, whereby an electric current could be induced to flow through a conductor that experiences a changing magnetic field. His ideas would not only enable Maxwell's later development of his theory of classical electromagnetism, but would directly lead to the development of the electric dynamo and electric motor, two technological advances that are the very foundations of the modern world. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.

  5. Drilling of Hybrid Titanium Composite Laminate (HTCL with Electrical Discharge Machining

    Directory of Open Access Journals (Sweden)

    M. Ramulu

    2016-09-01

    Full Text Available An experimental investigation was conducted to determine the application of die sinker electrical discharge machining (EDM as it applies to a hybrid titanium thermoplastic composite laminate material. Holes were drilled using a die sinker EDM. The effects of peak current, pulse time, and percent on-time on machinability of hybrid titanium composite material were evaluated in terms of material removal rate (MRR, tool wear rate, and cut quality. Experimental models relating each process response to the input parameters were developed and optimum operating conditions with a short cutting time, achieving the highest workpiece MRR, with very little tool wear were determined to occur at a peak current value of 8.60 A, a percent on-time of 36.12%, and a pulse time of 258 microseconds. After observing data acquired from experimentation, it was determined that while use of EDM is possible, for desirable quality it is not fast enough for industrial application.

  6. Induced electric fields in workers near low-frequency induction heating machines.

    Science.gov (United States)

    Kos, Bor; Valič, Blaž; Kotnik, Tadej; Gajšek, Peter

    2014-04-01

    Published data on occupational exposure to induction heating equipment are scarce, particularly in terms of induced quantities in the human body. This article provides some additional information by investigating exposure to two such machines-an induction furnace and an induction hardening machine. Additionally, a spatial averaging algorithm for measured fields we developed in a previous publication is tested on new data. The human model was positioned at distances where measured values of magnetic flux density were above the reference levels. All human exposure was below the basic restriction-the lower bound of the 0.1 top percentile induced electric field in the body of a worker was 0.193 V/m at 30 cm from the induction furnace.

  7. Replacement Condition Detection of Railway Point Machines Using an Electric Current Sensor.

    Science.gov (United States)

    Sa, Jaewon; Choi, Younchang; Chung, Yongwha; Kim, Hee-Young; Park, Daihee; Yoon, Sukhan

    2017-01-29

    Detecting replacement conditions of railway point machines is important to simultaneously satisfy the budget-limit and train-safety requirements. In this study, we consider classification of the subtle differences in the aging effect-using electric current shape analysis-for the purpose of replacement condition detection of railway point machines. After analyzing the shapes of after-replacement data and then labeling the shapes of each before-replacement data, we can derive the criteria that can handle the subtle differences between "does-not-need-to-be-replaced" and "needs-to-be-replaced" shapes. On the basis of the experimental results with in-field replacement data, we confirmed that the proposed method could detect the replacement conditions with acceptable accuracy, as well as provide visual interpretability of the criteria used for the time-series classification.

  8. Thermal and mechanical analyses of high-speed permanent-magnet electrical machines

    Energy Technology Data Exchange (ETDEWEB)

    Kolondzovski, Z.

    2010-07-01

    In the thesis, methods for the thermal and mechanical analyses of high-speed PM electrical machines are presented and implemented. The first method implemented for the thermal analysis is a combined 2D-3D numerical method. The thermal and turbulent properties of the flow, such as the temperature rise in the flow and the coefficients of thermal convection, are estimated using a 2D multi physics method that couples CFD with heat-transfer equations. The detailed distribution of the temperature rise in the whole solid domain of the machine is determined using a 3D numerical heat-transfer method. The temperature rises in the machine are also estimated with the traditional thermal-network method, which uses a totally different approach to the heat-transfer analysis. The methods used for the mechanical analysis of the machine include finite-element rotordynamics modelling of the rotor for estimation of the critical speeds and the shapes of the bending modes and also analytical estimation of the stress in the retaining sleeve. The implemented methods are used for the comparative thermal and mechanical analyses of three different high-speed PM rotor constructions. The first type of rotor construction is retained with a carbon-fibre sleeve and uses a shield for eddy currents made of aluminium. The second rotor construction is retained with a retaining sleeve made from the alloy Ti-6%Al-6%V-2%Sn and the sleeve of the third rotor construction is made from the alloy Ti-2.5%Cu. The last two rotor constructions do not have separate eddy-current shields. The comparative analysis shows that the rotor with a carbon-fibre sleeve and an aluminium eddy-current shield shows the best thermal properties. The rotor with a retaining sleeve made of the titanium alloy Ti-6%Al-6%V-2%Sn offers promising thermal properties because the critical temperatures in the rotor are not exceeded. Additionally, the same rotor construction provides the best rotordynamics properties when compared to the

  9. 78 FR 72552 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-12-03

    ...: We are adopting a new airworthiness directive (AD) for certain General Electric Company model GEnx... consumed more cyclic life than they would have in revenue flight cycles. These parts were then installed into engines and introduced into revenue service without adjustment to remaining cyclic life. This...

  10. Research on Modeling and Control of Regenerative Braking for Brushless DC Machines Driven Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jian-ping Wen

    2015-01-01

    Full Text Available In order to improve energy utilization rate of battery-powered electric vehicle (EV using brushless DC machine (BLDCM, the model of braking current generated by regenerative braking and control method are discussed. On the basis of the equivalent circuit of BLDCM during the generative braking period, the mathematic model of braking current is established. By using an extended state observer (ESO to observe actual braking current and the unknown disturbances of regenerative braking system, the autodisturbances rejection controller (ADRC for controlling the braking current is developed. Experimental results show that the proposed method gives better recovery efficiency and is robust to disturbances.

  11. Fiber optic vibration sensor for high-power electric machines realized using 3D printing technology

    Science.gov (United States)

    Igrec, Bojan; Bosiljevac, Marko; Sipus, Zvonimir; Babic, Dubravko; Rudan, Smiljko

    2016-03-01

    The objective of this work was to demonstrate a lightweight and inexpensive fiber-optic vibration sensor, built using 3D printing technology, for high-power electric machines and similar applications. The working principle is based on modulating the light intensity using a blade attached to a bendable membrane. The sensor prototype was manufactured using PolyJet Matrix technology with DM 8515 Grey 35 Polymer. The sensor shows linear response, expected bandwidth (< 150 Hz), and from our measurements we estimated the damping ratio for used polymer to be ζ ≍ 0.019. The developed prototype is simple to assemble, adjust, calibrate and repair.

  12. A Practical Torque Estimation Method for Interior Permanent Magnet Synchronous Machine in Electric Vehicles.

    Science.gov (United States)

    Wu, Zhihong; Lu, Ke; Zhu, Yuan

    2015-01-01

    The torque output accuracy of the IPMSM in electric vehicles using a state of the art MTPA strategy highly depends on the accuracy of machine parameters, thus, a torque estimation method is necessary for the safety of the vehicle. In this paper, a torque estimation method based on flux estimator with a modified low pass filter is presented. Moreover, by taking into account the non-ideal characteristic of the inverter, the torque estimation accuracy is improved significantly. The effectiveness of the proposed method is demonstrated through MATLAB/Simulink simulation and experiment.

  13. Evaluation of Fatigue Behavior and Surface Characteristics of Aluminum Alloy 2024 T6 After Electric Discharge Machining

    Science.gov (United States)

    Mehmood, Shahid; Shah, Masood; Pasha, Riffat Asim; Sultan, Amir

    2017-09-01

    The effect of electric discharge machining (EDM) on surface quality and consequently on the fatigue performance of Al 2024 T6 is investigated. Five levels of discharge current are analyzed, while all other electrical and nonelectrical parameters are kept constant. At each discharge current level, dog-bone specimens are machined by generating a peripheral notch at the center. The fatigue tests are performed on four-point rotating bending machine at room temperature. For comparison purposes, fatigue tests are also performed on the conventionally machined specimens. Linearized SN curves for 95% failure probability and with four different confidence levels (75, 90, 95 and 99%) are plotted for each discharge current level as well as for conventionally machined specimens. These plots show that the electric discharge machined (EDMed) specimens give inferior fatigue behavior as compared to conventionally machined specimen. Moreover, discharge current inversely affects the fatigue life, and this influence is highly pronounced at lower stresses. The EDMed surfaces are characterized by surface properties that could be responsible for change in fatigue life such as surface morphology, surface roughness, white layer thickness, microhardness and residual stresses. It is found that all these surface properties are affected by changing discharge current level. However, change in fatigue life by discharge current could not be associated independently to any single surface property.

  14. Hybrid Swarm Algorithms for Parameter Identification of an Actuator Model in an Electrical Machine

    Directory of Open Access Journals (Sweden)

    Ying Wu

    2011-01-01

    Full Text Available Efficient identification and control algorithms are needed, when active vibration suppression techniques are developed for industrial machines. In the paper a new actuator for reducing rotor vibrations in electrical machines is investigated. Model-based control is needed in designing the algorithm for voltage input, and therefore proper models for the actuator must be available. In addition to the traditional prediction error method a new knowledge-based Artificial Fish-Swarm optimization algorithm (AFA with crossover, CAFAC, is proposed to identify the parameters in the new model. Then, in order to obtain a fast convergence of the algorithm in the case of a 30 kW two-pole squirrel cage induction motor, we combine the CAFAC and Particle Swarm Optimization (PSO to identify parameters of the machine to construct a linear time-invariant(LTI state-space model. Besides that, the prediction error method (PEM is also employed to identify the induction motor to produce a black box model with correspondence to input-output measurements.

  15. A Review on Optimization of Process Parameters for Improving Performance in Electrical Discharge Machining

    Directory of Open Access Journals (Sweden)

    Viral B. Prajapati

    2014-02-01

    Full Text Available The correct selection of manufacturing conditions is one of the most important aspects to take into consideration in the majority of manufacturing processes and, particularly, in processes related to Electrical Discharge Machining (EDM. It is a capable of machining geometrically complex or hard material components, that are precise and difficult-to-machine such as heat treated tool steels, composites, super alloys, ceramics, carbides, heat resistant steels etc. being widely used in die and mold making industries, aerospace, aeronautics and nuclear industries. From the point of view of industrial applications, SS 410 is a very important material and that’s why for the purpose of experimentation SS 410 with copper electrode and EDM oil as dielectric has been used In the present work. I will take input parameter discharge current, pulse on time and pulse off time. Design of Experiment (DOE with full factorial design has been explored to produce 27 specimens on SS 410 by edm operation. MRR will be calculated from MRR equation and software available for it and then compare it. Collected data related to surface roughness have been utilized for optimization.

  16. Design and Optimization of Permanent Magnet Brushless Machines for Electric Vehicle Applications

    Directory of Open Access Journals (Sweden)

    Weiwei Gu

    2015-12-01

    Full Text Available In this paper, by considering and establishing the relationship between the maximum operating speed and d-axis inductance, a new design and optimization method is proposed. Thus, a more extended constant power speed range, as well as reduced losses and increased efficiency, especially in the high-speed region, can be obtained, which is essential for electric vehicles (EVs. In the first step, the initial permanent magnet (PM brushless machine is designed based on the consideration of the maximum speed and performance specifications in the entire operation region. Then, on the basis of increasing d-axis inductance, and meanwhile maintaining constant permanent magnet flux linkage, the PM brushless machine is optimized. The corresponding performance of the initial and optimal PM brushless machines are analyzed and compared by the finite-element method (FEM. Several tests are carried out in an EV simulation model based on the urban dynamometer driving schedule (UDDS for evaluation. Both theoretical analysis and simulation results verify the validity of the proposed design and optimization method.

  17. Rotating electrical machines. Part 2: Methods for determining losses and efficiency of rotating electrical machinery from tests (excluding machines for traction vehicles)

    CERN Document Server

    International Electrotechnical Commission. Geneva

    1972-01-01

    Applies to d.c. machines and to a.c. synchronous and induction machines. The principles can be applied to other types of machines such as rotary converters, a.c. commutator motors and single-phase induction motors for which other methods of determining losses are used.

  18. Mechanical characteristics of a double-fed machine in asynchronous mode and prospects of its application in the electric drive of mining machines

    Science.gov (United States)

    Ostrovlyanchik, V. Yu; Popolzin, I. Yu; Kubarev, V. A.; Marshev, D. A.

    2017-09-01

    The concept of a double-fed machine as an asynchronous motor with a phase rotor and a source of additional voltage is defined. Based on the analysis of a circuit replacing the double-fed machine, an expression is derived relating the moment, slip, amplitude and phase of additional voltage across the rotor. The conditions maximizing the moment with respect to amplitude and phase of additional voltage in the rotor circuit are also obtained, the phase surface of function of machine electromagnetic moment is constructed. The analysis of basic equation of electric drive motion in relation to electric drive of mine hoisting installations and the conclusion about the necessity of work in all four quadrants of coordinate plane “moment-slip” are made. Family of mechanical characteristics is constructed for a double-fed machine and its achievable speed control range in asynchronous mode is determined. Based on the type of mechanical characteristics and the calculated range of speed control, the conclusion is made about the suitability of using a dual-fed asynchronous machine for driving mine mechanisms with a small required speed control range and the need for organizing a combined operating mode for driving mine hoisting installations and other mechanisms with a large speed control range.

  19. Convective Heat Transfer Coefficients of Automatic Transmission Fluid Jets with Implications for Electric Machine Thermal Management: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Bennion, Kevin; Moreno, Gilberto

    2015-09-29

    Thermal management for electric machines (motors/ generators) is important as the automotive industry continues to transition to more electrically dominant vehicle propulsion systems. Cooling of the electric machine(s) in some electric vehicle traction drive applications is accomplished by impinging automatic transmission fluid (ATF) jets onto the machine's copper windings. In this study, we provide the results of experiments characterizing the thermal performance of ATF jets on surfaces representative of windings, using Ford's Mercon LV ATF. Experiments were carried out at various ATF temperatures and jet velocities to quantify the influence of these parameters on heat transfer coefficients. Fluid temperatures were varied from 50 degrees C to 90 degrees C to encompass potential operating temperatures within an automotive transaxle environment. The jet nozzle velocities were varied from 0.5 to 10 m/s. The experimental ATF heat transfer coefficient results provided in this report are a useful resource for understanding factors that influence the performance of ATF-based cooling systems for electric machines.

  20. Investigation of a Co-Axial Dual-Mechanical Ports Flux-Switching Permanent Magnet Machine for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Wei Hua

    2015-12-01

    Full Text Available In this paper, a co-axial dual-mechanical ports flux-switching permanent magnet (CADMP-FSPM machine for hybrid electric vehicles (HEVs is proposed and investigated, which is comprised of two conventional co-axial FSPM machines, namely one high-speed inner rotor machine and one low-speed outer rotor machine and a non-magnetic ring sandwiched in between. Firstly, the topology and operation principle of the CADMP-FSPM machine are introduced; secondly, the control system of the proposed electronically-controlled continuously-variable transmission (E-CVT system is given; thirdly, the key design specifications of the CADMP-FSPM machine are determined based on a conventional dual-mechanical ports (DMP machine with a wound inner rotor. Fourthly, the performances of the CADMP-FSPM machine and the normal DMP machine under the same overall volume are compared, and the results indicate that the CADMP-FSPM machine has advantages over the conventional DMP machine in the elimination of brushes and slip rings, improved thermal dissipation conditions for the inner rotor, direct-driven operation, more flexible modes, lower cogging torque and torque ripple, lower total harmonic distortion (THD values of phase PM flux linkage and phase electro-motive force (EMF, higher torque output capability and is suitable for the E-CVT systems. Finally, the pros and cons of the CADMP-FSPM machine are highlighted. This paper lays a theoretical foundation for further research on CADMP-FSPM machines used for HEVs.

  1. Electrical discharge machining: occupational hygienic characterization using emission-based monitoring.

    Science.gov (United States)

    Evertz, Sven; Dott, Wolfgang; Eisentraeger, Adolf

    2006-09-01

    Hazardous potential in industrial environments is normally assessed by means of immission-based sampling and analyses. This approach is not adequate, if effects of specific technical adjustments at machine tools or working processes on hygienic parameters should be assessed. This work has focused on the optimization of a manufacturing process (electrical discharge machining, EDM), with regard to risk reduction assessment. It is based on emission analyses rather than immision analyses. Several technical EDM parameters have been examined for their influence on air-based emissions. Worktools and workpieces used have a strong influence on aliphatic compounds and metals but not on volatile organic compounds (benzene, toluene, ethylene-benzene and xylene (BTEX)) and polycyclic aromatic hydrocarbons (PAHs) in air emissions. Increasing the dielectric (mineral oil) level above processing location decreases BTEX, chromium, nickel and PAH emissions. Aliphatic compounds, in contrast, increase in air emissions. EDM current used has a positive relationship with all substances analyzed in air emissions. Indicative immission concentrations, as can be expected under EDM conditions, are estimated in a predictive scenario. The results of this characterization give rise to an important conclusion in that risk assessment so far has been using incorrect parameters: total aliphatic compounds. Maximum level of chromium is reached long before limit values of aliphatic compounds are exceeded. Because of the fact that metals, like chromium, also have a higher hazardous potential, metal analysis should be introduced in future risk assessment. This experimental approach, that captures total emission of the electrical discharge machine, and is not solely based on immission values, has lead to a better understanding of the production process. This information is used to extract recommendations regarding monitoring aspects and protection measures.

  2. A general theory of phase noise in electrical oscillators

    OpenAIRE

    Hajimiri, Ali; Lee, Thomas H.

    1998-01-01

    A general model is introduced which is capable of making accurate, quantitative predictions about the phase noise of different types of electrical oscillators by acknowledging the true periodically time-varying nature of all oscillators. This new approach also elucidates several previously unknown design criteria for reducing close-in phase noise by identifying the mechanisms by which intrinsic device noise and external noise sources contribute to the total phase noise. In particular, it expl...

  3. Influence of Different Rotor Teeth Shapes on the Performance of Flux Switching Permanent Magnet Machines Used for Electric Vehicles

    OpenAIRE

    Jing Zhao; Yashuang Yan; Bin Li; Xiangdong Liu; Zhen Chen

    2014-01-01

    This paper investigated a 12-slot/11-pole flux switching permanent magnet (FSPM) machine used for electric vehicles (EVs). Five novel rotor teeth shapes are proposed and researched to reduce the cogging torque and torque ripple of the FSPM machine. These rotor teeth shapes are notched teeth, stepped teeth, eccentric teeth, combination of notched and stepped teeth, and combination of notched and eccentric teeth. They are applied on the rotor and optimized, respectively. The influences of diffe...

  4. A New Energy-Based Method for 3-D Finite-Element Nonlinear Flux Linkage computation of Electrical Machines

    DEFF Research Database (Denmark)

    Lu, Kaiyuan; Rasmussen, Peter Omand; Ritchie, Ewen

    2011-01-01

    This paper presents a new method for computation of the nonlinear flux linkage in 3-D finite-element models (FEMs) of electrical machines. Accurate computation of the nonlinear flux linkage in 3-D FEM is not an easy task. Compared to the existing energy-perturbation method, the new technique......-perturbation method. The new method proposed is validated using experimental results on two different permanent magnet machines....

  5. An experimental and computational investigation of electrical resistivity imaging for prediction ahead of tunnel boring machines

    Science.gov (United States)

    Schaeffer, Kevin P.

    Tunnel boring machines (TBMs) are routinely used for the excavation of tunnels across a range of ground conditions, from hard rock to soft ground. In complex ground conditions and in urban environments, the TBM susceptible to damage due to uncertainty of what lies ahead of the tunnel face. The research presented here explores the application of electrical resistivity theory for use in the TBM tunneling environment to detect changing conditions ahead of the machine. Electrical resistivity offers a real-time and continuous imaging solution to increase the resolution of information along the tunnel alignment and may even unveil previously unknown geologic or man-made features ahead of the TBM. The studies presented herein, break down the tunneling environment and the electrical system to understand how its fundamental parameters can be isolated and tested, identifying how they influence the ability to predict changes ahead of the tunnel face. A proof-of-concept, scaled experimental model was constructed in order assess the ability of the model to predict a metal pipe (or rod) ahead of face as the TBM excavates through a saturated sand. The model shows that a prediction of up to three tunnel diameters could be achieved, but the unique presence of the pipe (or rod) could not be concluded with certainty. Full scale finite element models were developed in order evaluate the various influences on the ability to detect changing conditions ahead of the face. Results show that TBM/tunnel geometry, TBM type, and electrode geometry can drastically influence prediction ahead of the face by tens of meters. In certain conditions (i.e., small TBM diameter, low cover depth, large material contrasts), changes can be detected over 100 meters in front of the TBM. Various electrode arrays were considered and show that in order to better detect more finite differences (e.g., boulder, lens, pipe), the use of individual cutting tools as electrodes is highly advantageous to increase spatial

  6. Generalization Evaluation of Machine Learning Numerical Observers for Image Quality Assessment.

    Science.gov (United States)

    Kalayeh, Mahdi M; Marin, Thibault; Brankov, Jovan G

    2013-06-01

    In this paper, we present two new numerical observers (NO) based on machine learning for image quality assessment. The proposed NOs aim to predict human observer performance in a cardiac perfusion-defect detection task for single-photon emission computed tomography (SPECT) images. Human observer (HumO) studies are now considered to be the gold standard for task-based evaluation of medical images. However such studies are impractical for use in early stages of development for imaging devices and algorithms, because they require extensive involvement of trained human observers who must evaluate a large number of images. To address this problem, numerical observers (also called model observers) have been developed as a surrogate for human observers. The channelized Hotelling observer (CHO), with or without internal noise model, is currently the most widely used NO of this kind. In our previous work we argued that development of a NO model to predict human observers' performance can be viewed as a machine learning (or system identification) problem. This consideration led us to develop a channelized support vector machine (CSVM) observer, a kernel-based regression model that greatly outperformed the popular and widely used CHO. This was especially evident when the numerical observers were evaluated in terms of generalization performance. To evaluate generalization we used a typical situation for the practical use of a numerical observer: after optimizing the NO (which for a CHO might consist of adjusting the internal noise model) based upon a broad set of reconstructed images, we tested it on a broad (but different) set of images obtained by a different reconstruction method. In this manuscript we aim to evaluate two new regression models that achieve accuracy higher than the CHO and comparable to our earlier CSVM method, while dramatically reducing model complexity and computation time. The new models are defined in a Bayesian machine-learning framework: a channelized

  7. EFFECT OF TOOL POLARITY ON THE MACHINING CHARACTERISTICS IN ELECTRIC DISCHARGE MACHINING OF SILVER STEEL AND STATISTICAL MODELLING OF THE PROCESS

    Directory of Open Access Journals (Sweden)

    DILSHAD AHMAD KHAN,

    2011-06-01

    Full Text Available Electric discharge machining (EDM is a thermoelectric process in which electrical energy is converted into thermal energy and this thermal energy is used for the machining purpose. It is the common practice in EDM to make tool negative and work piece positive (direct polarity , but researches shows that reverse of it is also possible in which tool is positive and work piece is negative ( reverse polarity, but not much work has been carried out on the reverse polarity till now. This paper discusses the effect of tool polarity on the machining characteristics in electric discharge machining of silver steel. High metal removal rate, low relative electrode wear and good surface finish are conflicting goals, which can not be achieved simultaneously with a particular combination of control settings. To achieve the best machining results, the goal has to be taken separately in different phases of work with different emphasis. A 32 factorial design has been used for planning of experimental conditions. Copper is used as tool material and Silver steel of 28 grade is selected as work piece material with positive and negative polarities. The effectiveness of EDM process with silver steel is evaluated in terms of metal removal rate (MRR, percent relative electrode wear (%REW and the surface roughness (S.R ofthe work piece produced at different current and pulse duration levels. In this experimental work spark erosion oil (trade name IPOL is taken as a dielectric and experiments have been conducted at 50% duty factor. The study reveals that direct polarity is suitable for higher metal removal rate and lower relative electrode wear but reverse polarity gives better surface finish as compared to direct polarity. Direct polarity gives 4-11 times more MRR and 5 times less relative electrode wear as compared to reverse polarity, and reverse polarity gives 1.3-2.7 times better surface finish as compared to direct polarity. Second order regression model is also

  8. Electric field gradient, generalized Sternheimer shieldings and electric field gradient polarizabilities by multiconfigurational SCF response

    Science.gov (United States)

    Rizzo, Antonio; Ruud, Kenneth; Helgaker, Trygve; Jaszuński, Michał

    1998-08-01

    The electric field gradient (EFG) at the nuclei, the generalized Sternheimer shielding constants and the EFG electric dipole polarizabilities are computed for eight small molecules employing multiconfigurational self-consistent field wave functions and the corresponding linear and quadratic response functions. The molecules studied are H2, N2, CO, HF, C2H2, HCl, HCN, and HNC, all of which are linear. For the hydrogen molecule, full configuration-interaction results for the properties are also reported. The dependence of the computed quantities on the basis set and the electron-correlation treatment is analyzed.

  9. A derivation of the generalized model of strains during bending of metal tubes at bending machines

    OpenAIRE

    Śloderbach Z.

    2014-01-01

    According to the postulate concerning a local change of the “actual active radius” with a bending angle in the bend zone, a generalized model of strain during metal tube bending was derived. The tubes should be subjected to bending at tube bending machines by the method of wrapping at the rotating template and with the use of a lubricated steel mandrel. The model is represented by three components of strain in the analytic form, including displacement of the neutral axis. Generalization of th...

  10. Predicting Future Hourly Residential Electrical Consumption: A Machine Learning Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Richard E [ORNL; New, Joshua Ryan [ORNL; Parker, Lynne Edwards [ORNL

    2012-01-01

    Whole building input models for energy simulation programs are frequently created in order to evaluate specific energy savings potentials. They are also often utilized to maximize cost-effective retrofits for existing buildings as well as to estimate the impact of policy changes toward meeting energy savings goals. Traditional energy modeling suffers from several factors, including the large number of inputs required to characterize the building, the specificity required to accurately model building materials and components, simplifying assumptions made by underlying simulation algorithms, and the gap between the as-designed and as-built building. Prior works have attempted to mitigate these concerns by using sensor-based machine learning approaches to model energy consumption. However, a majority of these prior works focus only on commercial buildings. The works that focus on modeling residential buildings primarily predict monthly electrical consumption, while commercial models predict hourly consumption. This means there is not a clear indicator of which techniques best model residential consumption, since these methods are only evaluated using low-resolution data. We address this issue by testing seven different machine learning algorithms on a unique residential data set, which contains 140 different sensors measurements, collected every 15 minutes. In addition, we validate each learner's correctness on the ASHRAE Great Energy Prediction Shootout, using the original competition metrics. Our validation results confirm existing conclusions that Neural Network-based methods perform best on commercial buildings. However, the results from testing our residential data set show that Feed Forward Neural Networks, Support Vector Regression (SVR), and Linear Regression methods perform poorly, and that Hierarchical Mixture of Experts (HME) with Least Squares Support Vector Machines (LS-SVM) performs best - a technique not previously applied to this domain.

  11. Performance Optimization of Electrical Discharge Machining (Die Sinker for Al-6061 via Taguchi Approach

    Directory of Open Access Journals (Sweden)

    Muhammad Qaiser Saleem

    2015-04-01

    Full Text Available This paper parametrically optimizes the EDM (Electrical Discharge Machining process in die sinking mode for material removal rate, surface roughness and edge quality of aluminum alloy Al-6061. The effect of eight parameters namely discharge current, pulse on-time, pulse off-time, auxiliary current, working time, jump time distance, servo speed and work piece hardness are investigated. Taguchi's orthogonal array L18 is employed herein for experimentation. ANOVA (Analysis of Variance with F-ratio criterion at 95% confidence level is used for identification of significant parameters whereas SNR (Signal to Noise Ratio is used for determination of optimum levels. Optimization obtained for Al-6061 with parametric combination investigated herein is validated by the confirmation run.

  12. Parallel Sparse Matrix Solver on the GPU Applied to Simulation of Electrical Machines

    CERN Document Server

    Rodrigues, Antonio Wendell De Oliveira; Menach, Yvonnick Le; Dekeyser, Jean-Luc

    2010-01-01

    Nowadays, several industrial applications are being ported to parallel architectures. In fact, these platforms allow acquire more performance for system modelling and simulation. In the electric machines area, there are many problems which need speed-up on their solution. This paper examines the parallelism of sparse matrix solver on the graphics processors. More specifically, we implement the conjugate gradient technique with input matrix stored in CSR, and Symmetric CSR and CSC formats. This method is one of the most efficient iterative methods available for solving the finite-element basis functions of Maxwell's equations. The GPU (Graphics Processing Unit), which is used for its implementation, provides mechanisms to parallel the algorithm. Thus, it increases significantly the computation speed in relation to serial code on CPU based systems.

  13. Shaping of steel mold surface of lens array by electrical discharge machining with spherical ball electrode.

    Science.gov (United States)

    Takino, Hideo; Hosaka, Takahiro

    2016-06-20

    We propose a method for fabricating a spherical lens array mold by electrical discharge machining (EDM) with a ball-type electrode. The electrode is constructed by arranging conductive spherical balls in an array. To fundamentally examine the applicability of the proposed EDM method to the fabrication of lens array molds, we use an electrode having a single ball to shape a lens array mold made of stainless steel with 16 spherical elements, each having a maximum depth of 0.5 mm. As a result, a mold surface is successfully shaped with a peak-to-valley shape accuracy of approximately 10 μm, and an average surface roughness of 0.85 μm.

  14. Electrical performance of a string of magnets representing a half-cell of the LHC machine

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Mateos, F.; Coull, L.; Dahlerup-Petersen, K.; Hagedorn, D.; Krainz, G.; Rijllart, A. [European Organization for Nuclear Research, Geneva (Switzerland); McInturff, A. [Lawrence Berkeley Lab., CA (United States)

    1995-06-21

    Tests have been carried out on a string prototype superconducting magnets, consisting of one double-quadrupole and two double-dipoles forming the major part of a half-cell of the LHC machine. The magnets are protected individually by ``cold diodes`` and quench heaters. The electrical aspects of these tests are described here. The performance during quench of the protection diodes and the associated interconnections was studied. Tests determined the magnet quench performance in training and at different ramp-rates, and investigated the inter-magnet propagation of quenches. Current lead and inter-magnet contact resistances were controlled and the performance of the power converter and the dump switches assessed.

  15. 微细电火花加工技术%Micro electrical discharge machining technology

    Institute of Scientific and Technical Information of China (English)

    余祖元; 郭东明; 贾振元

    2007-01-01

    微细电火花加工(Micro Electrical Discharge Machining,Micro EDM)作为微细加工技术的一种,可以在任何导电材料上加工高精度、大深宽比微细三维型腔,以满足日益增长的产品微小型化需求.针对微细电火花加工中的一些关键问题,如微细电极损耗与补偿,大深径比微孔加工,本文着重介绍部分研究结果,以期在微细电火花加工技术的应用中,提供解决对策.

  16. Effect of TiN powder mixed in Electrical Discharge Machining

    Science.gov (United States)

    Muttamara, A.; Mesee, J.

    2016-11-01

    Many trials were studied about powder mixed in Electrical Discharge Machining (EDM). The experiments were carried for improving surface characteristics and related to the surface modification. The experiment was carried out using a copper tool electrode and EDMed in titanium nitride (TiN) powder mixed in dielectric fluid. In this research, to obtain the even modified layer, the effects of EDMed conditions were investigated. The EDMed surfaces were observed by SEM. Under the suitable discharge conditions in TiN powder mixed kerosene, the stable thick TiN layer adhered on the workpiece surface. The microcrack length per unit area treated in TiN mixed kerosene was greater than that treated in normal kerosene. Titanium carbon nitride (TiCN) was found on the modified layer by XRD analysis. The effect of the diffusion of carbon during cooling on the characteristics of the recast layer was discussed.

  17. Comparative Study on Electrical Discharge Machining of Ultrafine-Grain Al, Cu, and Steel

    Science.gov (United States)

    Mahdieh, Mohammad Sajjad; Mahdavinejad, RamezanAli

    2016-12-01

    Recently, manufacturing of industrial parts out of ultrafine-grain (UFG) materials became prevalent due to their lightweight and high strength. Machining processes such as electrical discharge machining (EDM) are necessary to produce parts with accurate dimensions and tolerance. On the other hand, recast layer, heat-affected zone (HAZ), and the micro-cracks are the effects of the EDM process, reducing the surface integrity of the workpieces. These undesirable effects are more noticeable on the UFG materials because of the excess energy stored in them. This excess stored energy is because of the high strain and stress imposed on the microstructure of UFG material during severe plastic deformation processes. In this article, a comparative study is conducted about the effects of the EDM process on three applicable UFG materials: aluminum, steel, and copper. These UFG materials are produced by equal channel angular pressing, which is a well-known method in producing UFG materials. The surface integrity factors including thickness of recast layer and HAZ, cracks density, micro-hardness, and surface roughness are measured and investigated via optical microscopy, scanning electron microscopy, X-ray diffraction technique, roughness tester, and micro-hardness tester. Results show that after the EDM process, thicker recast layer, and HAZ, more cracks density and more microstructural changes are observed among the UFG aluminum samples than among the copper and steel samples.

  18. Multi-objective optimization of the dry electric discharge machining process

    CERN Document Server

    Saha, Sourabh

    2009-01-01

    Dry Electric Discharge Machining (EDM) is an environment-friendly modification of the conventional EDM process, which is obtained by replacing the liquid dielectric by a gaseous medium. In this study, multi-objective optimization of dry EDM process has been done using the non dominated sorting genetic algorithm (NSGA II), with material removal rate (MRR) and surface roughness (Ra) as the objective functions. Experiments were conducted with air as dielectric to develop polynomial models of MRR and Ra in terms of the six input parameters: gap voltage, discharge current, pulse-on time, duty factor, air pressure and spindle speed. A Pareto-optimal front was then obtained using NSGA II. Analysis of the front was done to identify separate regions for finish and rough machining. Designed experiments were then conducted in these focused regions to verify the optimization results and to identify the region-specific characteristics of the process. Finishing conditions were obtained at low current, high pulse-on time an...

  19. Towards smart energy systems: application of kernel machine regression for medium term electricity load forecasting.

    Science.gov (United States)

    Alamaniotis, Miltiadis; Bargiotas, Dimitrios; Tsoukalas, Lefteri H

    2016-01-01

    Integration of energy systems with information technologies has facilitated the realization of smart energy systems that utilize information to optimize system operation. To that end, crucial in optimizing energy system operation is the accurate, ahead-of-time forecasting of load demand. In particular, load forecasting allows planning of system expansion, and decision making for enhancing system safety and reliability. In this paper, the application of two types of kernel machines for medium term load forecasting (MTLF) is presented and their performance is recorded based on a set of historical electricity load demand data. The two kernel machine models and more specifically Gaussian process regression (GPR) and relevance vector regression (RVR) are utilized for making predictions over future load demand. Both models, i.e., GPR and RVR, are equipped with a Gaussian kernel and are tested on daily predictions for a 30-day-ahead horizon taken from the New England Area. Furthermore, their performance is compared to the ARMA(2,2) model with respect to mean average percentage error and squared correlation coefficient. Results demonstrate the superiority of RVR over the other forecasting models in performing MTLF.

  20. 76 FR 70166 - Electrical Standards for Construction and General Industry; Extension of the Office of Management...

    Science.gov (United States)

    2011-11-10

    ... installation and maintenance of electric utilization equipment that prevent death and serious injuries among... Occupational Safety and Health Administration Electrical Standards for Construction and General Industry... collection requirements contained in the Electrical Standards for Construction (29 CFR part 1926, Subpart...

  1. General Electric Reactor Protection System Unavailability, 1984-1995

    Energy Technology Data Exchange (ETDEWEB)

    C. D. Gentillon; D. Rasmuson (USNRC); H. Hamzehee; M. B. Calley; S. A. Eide; T. Wierman (INEEL)

    1999-08-01

    An analysis was performed of the safety-related performance of the reactor protection system (RPS) at U.S. General Electric commercial reactors during the period 1984 through 1995. RPS operational data were collected from the Nuclear Plant Reliability Data System and Licensee Event Reports. A risk-based analysis was performed on the data to estimate the observed unavailability of the RPS, based on a fault tree model of the system. Results were compared with existing unavailability estimates from Individual Plant Examinations and other reports.

  2. General Electric Reactor Protection System Unavailability, 1984--1995

    Energy Technology Data Exchange (ETDEWEB)

    Eide, Steven Arvid; Calley, Michael Brennan; Gentillon, Cynthia Ann; Wierman, Thomas Edward; Hamzehee, H.; Rasmuson, D.

    1999-08-01

    An analysis was performed of the safety-related performance of the reactor protection system (RPS) at U. S. General Electric commercial reactors during the period 1984 through 1995. RPS operational data were collected from the Nuclear Plant Reliability Data System and Licensee Event Reports. A risk-based analysis was performed on the data to estimate the observed unavailability of the RPS, based on a fault tree model of the system. Results were compared with existing unavailability estimates from Individual Plant Examinations and other reports.

  3. 75 FR 47644 - General Electric Company, Transportation Division, Including On-Site Leased Workers From Adecco...

    Science.gov (United States)

    2010-08-06

    ... 3, 2010, the USCIT remanded United Electrical, Radio and Machine Workers of America, Local 506 v..., Pennsylvania (hereafter referred to as the subject facility). On July 1, 2009, United Electrical, Radio and... the subject facility. In accordance with section 223 of the Act, 19 U.S.C. 2273, I make the...

  4. Design Comparison of Inner and Outer Rotor of Permanent Magnet Flux Switching Machine for Electric Bicycle Application

    Science.gov (United States)

    Jusoh, L. I.; Sulaiman, E.; Bahrim, F. S.; Kumar, R.

    2017-08-01

    Recent advancements have led to the development of flux switching machines (FSMs) with flux sources within the stators. The advantage of being a single-piece machine with a robust rotor structure makes FSM an excellent choice for speed applications. There are three categories of FSM, namely, the permanent magnet (PM) FSM, the field excitation (FE) FSM, and the hybrid excitation (HE) FSM. The PMFSM and the FEFSM have their respective PM and field excitation coil (FEC) as their key flux sources. Meanwhile, as the name suggests, the HEFSM has a combination of PM and FECs as the flux sources. The PMFSM is a simple and cheap machine, and it has the ability to control variable flux, which would be suitable for an electric bicycle. Thus, this paper will present a design comparison between an inner rotor and an outer rotor for a single-phase permanent magnet flux switching machine with 8S-10P, designed specifically for an electric bicycle. The performance of this machine was validated using the 2D- FEA. As conclusion, the outer-rotor has much higher torque approximately at 54.2% of an innerrotor PMFSM. From the comprehensive analysis of both designs it can be conclude that output performance is lower than the SRM and IPMSM design machine. But, it shows that the possibility to increase the design performance by using “deterministic optimization method”.

  5. SURVEILLANCE OF BACTERIAL CONTAMINATION OF ANESTHESIA MACHINE AND PERIPHERAL INTRAVENOUS CANNULA DURING GENERAL ANESTHESIA

    Directory of Open Access Journals (Sweden)

    Ch. Srinivas

    2015-01-01

    Full Text Available BACKGROUND: Given the expanding role of the anesthesiologist as the “total perioperative physician,” the increasing number of invasive procedures performed by anesthesiologists, and the increase in the prevalence of emerging diseases, stringent attention to infection control practices is paramount. AIM : To find out the bacterial contamination of anesthesia machine and internal lumen of the injection port of peri pheral intravenous cannula, and evaluation of its risk factors during general anesthesia procedures. MATERIALS AND METHODS: 50 general anaesthesia procedures were selected randomly after the approval of ethics committee and informed consent from the patien t. Samples were taken for bacterial culture on 2 sites in anesthesia machine (Adjustable pressure limiting valve {APL} and agent concentration dial of inhaled anesthetics{AD} and internal lumen of the injection port of peripheral intravenous cannula befor e starting and after completion of procedures. Bacteria and colony count were identified according to standard laboratory methods . RESULTS : Adjustable pressure limiting valve area was contaminated with bacteria in 12% (6/50 before starting procedure and 34% (17/50 after completion of procedures. Agent concentration dial of inhaled anesthetic site was contaminated with bacteria in 10% (5/50 before starting procedure and 28% (14/50 after completion of procedures. Bacterial contamination occurred in the i nternal lumen of the injection port of peripheral intravenous cannula in 16% (8/50 during general anesthesia. Isolated bacteria in anesthesia machine and peripheral intra venous cannula sites are STAPHYLO COCCI, STREPTOCOCCI, MICRO COCCI, ENTERO COCCI, E. COLI, and PSEUDOMONAS . CONCLUSION: Bacterial contamination is significantly associated with procedure order in a day (bacterial contamination rate is increased from first procedure to fifth procedure in a day. It is significantly associated with surgical s pecialty highest in

  6. Dual-Electrical-Port Control of Cascaded Doubly-Fed Induction Machine for EV/HEV Applications

    DEFF Research Database (Denmark)

    Han, Peng; Cheng, Ming; Chen, Zhe

    2017-01-01

    This paper presents a dual-electrical-port control scheme for four-quadrant operation of cascaded doubly-fed induction machine (CDFIM), which has conventionally been used as a variable-speed drive or variable-speed constant-frequency generator for limited-speed-range applications. The proposed...

  7. Single-Electrical-Port Control of Cascaded Doubly-Fed Induction Machine for EV/HEV Applications

    DEFF Research Database (Denmark)

    Han, Peng; Cheng, Ming; Chen, Zhe

    2017-01-01

    A single-electrical-port control scheme, for four-quadrant operation of cascaded doubly-fed induction machine (CDFIM), which has long been conceived as a motor or generator only suitable for limited two-quadrant operation, is proposed and theoretically demonstrated. The drive system is configured...

  8. Effect of Electric Discharge Machining on Material Removal Rate and White Layer Composition

    Directory of Open Access Journals (Sweden)

    SHAHID MEHMOOD

    2017-01-01

    Full Text Available In this study the MRR (Material Removal Rate of the aerospace grade (2024 T6 aluminum alloy 2024 T6 has been determined with copper electrode and kerosene oil is used as dielectric liquid. Discharge energy is controlled by electric current while keeping Pulse-ON time and Pulse-OFF time as constant. The characteristics of the EDMed (Electric Discharge Machined surface are discussed. The sub-surface defect due to arcing has been explained. As the surface material of tool electrode and workpiece melts simultaneously and there are chances of the contamination of both surfaces by the contents of each other. Therefore, the EDS (Energy Dispersive Spectroscopy of the white layer and base material of the workpiece was performed by SEM (Scanning Electron Microscope at the discharge currents of 3, 6 and 12 amperes. It was conformed that the contamination of the surface of the workpiece material occurred by carbon, copper and oxygen contents. The quantitative analysis of these contents with respect to the discharge current has been presented in this paper.

  9. Investigation of the influence of air gap thickness and eccentricity on the noise of the rotating electrical machine

    Directory of Open Access Journals (Sweden)

    Donát M.

    2013-12-01

    Full Text Available This article deals with the numerical modelling of the dynamic response of the rotating electrical machine on the application of the magnetic forces. The special attention is paid to the modelling of the magnetic forces that act on the stator winding of the machine and the computational model of the modal properties of the stator winding. The created computational model was used to investigation of the influence of the nominal air gap thickness and the air gap eccentricity on the sound power radiated by outer surface of the stator of the machine. The obtained results show that the nominal air gap thickness has slightly greater influence on the sound power of the machine than eccentricity of the air gap.

  10. The study on the atomic force microscopy base nanoscale electrical discharge machining.

    Science.gov (United States)

    Huang, Jen-Ching; Chen, Chung-Ming

    2012-01-01

    This study proposes an innovative atomic force microscopy (AFM) based nanoscale electrical discharge machining (AFM-based nanoEDM) system which combines an AFM with a self-produced metallic probe and a high-voltage generator to create an atmospheric environment AFM-based nanoEDM system and a deionized water (DI water) environment AFM-based nanoEDM system. This study combines wire-cut processing and electrochemical tip sharpening techniques on a 40-µm thick stainless steel sheet to produce a high conductive AFM probes, the production can withstand high voltage and large current. The tip radius of these probes is approximately 40 nm. A probe test was executed on the AFM using probes to obtain nanoscales morphology of Si wafer surface. The silicon wafer was as a specimen to carry out AFM-base nanoEDM process in atmospheric and DI water environments by AFM-based nanoEDM system. After experiments, the results show that the atmospheric and DI water environment AFM-based nanoEDM systems operate smoothly. From experimental results, it can be found that the electric discharge depth of the silicon wafer at atmospheric environments is a mere 14.54 nm. In a DI water environment, the depth of electric discharge of the silicon wafer can reach 25.4 nm. This indicates that the EDM ability of DI water environment AFM-based nanoEDM system is higher than that of atmospheric environment AFM-based nanoEDM system. After multiple nanoEDM process, the tips become blunt. After applying electrochemical tip sharpening techniques, the tip radius can return to approximately 40 nm. Therefore, AFM probes produced in this study can be reused.

  11. PLL Usage in the General Machine Timing System for the LHC

    CERN Document Server

    Alvarez-Sanchez, P; King, Q; Lewis, J; Serrano, J; Todd, B

    2003-01-01

    Analogue PLLs have been successfully used for decades to recover clocks and clean the jitter introduced by transmission media. Nevertheless the design parameters are hard to change once the PCB has been mounted. Digital PLLs overcome this problem. They can be either completely digital, substituting the VCO by a Numeric Oscillator, or they can keep a VCXO in case a low jitter is needed. This paper describes both configurations and gives lab results for the latter. This architecture will be used in every General Machine Timing reveiver card for the LHC.

  12. The monitoring of transient regimes on machine tools based on speed, acceleration and active electric power absorbed by motors

    Science.gov (United States)

    Horodinca, M.

    2016-08-01

    This paper intend to propose some new results related with computer aided monitoring of transient regimes on machine-tools based on the evolution of active electrical power absorbed by the electric motor used to drive the main kinematic chains and the evolution of rotational speed and acceleration of the main shaft. The active power is calculated in numerical format using the evolution of instantaneous voltage and current delivered by electrical power system to the electric motor. The rotational speed and acceleration of the main shaft are calculated based on the signal delivered by a sensor. Three real-time analogic signals are acquired with a very simple computer assisted setup which contains a voltage transformer, a current transformer, an AC generator as rotational speed sensor, a data acquisition system and a personal computer. The data processing and analysis was done using Matlab software. Some different transient regimes were investigated; several important conclusions related with the advantages of this monitoring technique were formulated. Many others features of the experimental setup are also available: to supervise the mechanical loading of machine-tools during cutting processes or for diagnosis of machine-tools condition by active electrical power signal analysis in frequency domain.

  13. Power distribution of a co-axial dual-mechanical-port flux-switching permanent magnet machine for fuel-based extended range electric vehicles

    Science.gov (United States)

    Zhou, Lingkang; Hua, Wei; Zhang, Gan

    2017-05-01

    In this paper, power distribution between the inner and outer machines of a co-axial dual-mechanical-port flux-switching permanent magnet (CADMP-FSPM) machine is investigated for fuel-based extended range electric vehicle (ER-EV). Firstly, the topology and operation principle of the CADMP-FSPM machine are introduced, which consist of an inner FSPM machine used for high-speed, an outer FSPM machine for low-speed, and a magnetic isolation ring between them. Then, the magnetic field coupling of the inner and outer FSPM machines is analyzed with more attention paid to the optimization of the isolation ring thickness. Thirdly, the power-dimension (PD) equations of the inner and outer FSPM machines are derived, respectively, and thereafter, the PD equation of the whole CADMP-FSPM machine can be given. Finally, the PD equations are validated by finite element analysis, which supplies the guidance on the design of this type of machines.

  14. Rapid prototyping of zirconium diboride/copper electrical discharge machining electrodes

    Science.gov (United States)

    Stucker, Brent Eric

    The acceptance of rapid prototyping (RP) as the predominant technique for producing polymer and paper parts directly from computer-aided design (CAD) models has led many corporations and universities to try to extend its capabilities to more robust materials. In addition to producing prototype metal and ceramic parts, a significant effort has been made to create parts that are useful as tools and dies or that reduce the time necessary to create tools and dies. Most materials used for tools and dies are very hard, because they need to be able to withstand millions of cycles before failing. Electrical discharge machining (EDM) is the most common method used to machine tools and dies out of hard materials. A method for producing EDM electrodes using RP could greatly reduce the time and cost involved in creating tools and dies. A new EDM electrode material made up of zirconium diboride and copper (ZrBsb2/Cu) that is superior to traditional EDM electrodes has been investigated. The processing techniques necessary for creating Zrsb2/Cu electrodes from powders of ZrB2 and copper have been developed. These ZrBsb2/Cu electrodes have a better wear ratio and a faster sink rate than graphite, copper or tungsten/copper EDM electrodes. Performance variables that were tracked are: (1) wear ratio, (2) sink rate and (3) surface finish, where ZrBsb2/Cu, copper, graphite and W/Cu were used as anodes (electrodes) and stainless steel as cathodes (workpieces). The ZrBsb2/Cu electrode material system retains its superior EDM electrode performance across a number of materials processing and compositional variations. Scanning electron microscopy (SEM) was used to study the electrodes after EDM. These SEM observations facilitated an understanding of the superior EDM electrode performance characteristics of ZrBsb2/Cu to traditional EDM electrode material systems. A method for creating geometrically-complex ZrBsb2/Cu EDM electrodes using the selective laser sintering (SLS) RP technique was

  15. Alternating current multi-circuit electric machines a new approach to the steady-state parameter determination

    CERN Document Server

    Asanbayev, Valentin

    2015-01-01

    This book details an approach for realization of the field decomposition concept. The book presents the  methods as well as techniques and procedures for establishing electric machine circuit-loops and determining their parameters. The methods developed have been realized using the models of machines with laminated and solid rotor having classical structure. The use of such models are well recognized and simplifies practical implementation of the obtained results. This book also: ·         Includes methods for a construction of electric machine equivalent circuits that allows the replacement of the field models of the machine with simple circuit models ·         Demonstrates the practical implementation of the proposed techniques and procedures ·         Presents parameters of the circuit-loops in the form most convenient for practical implementation ·         Uses methods based on machine models widely used in practice

  16. A generalized exponential time series regression model for electricity prices

    DEFF Research Database (Denmark)

    Haldrup, Niels; Knapik, Oskar; Proietti, Tomasso

    We consider the issue of modeling and forecasting daily electricity spot prices on the Nord Pool Elspot power market. We propose a method that can handle seasonal and non-seasonal persistence by modelling the price series as a generalized exponential process. As the presence of spikes can distort...... the estimation of the dynamic structure of the series we consider an iterative estimation strategy which, conditional on a set of parameter estimates, clears the spikes using a data cleaning algorithm, and reestimates the parameters using the cleaned data so as to robustify the estimates. Conditional...... on the estimated model, the best linear predictor is constructed. Our modeling approach provides good fit within sample and outperforms competing benchmark predictors in terms of forecasting accuracy. We also find that building separate models for each hour of the day and averaging the forecasts is a better...

  17. Optimization of Electrical Discharge Machining Characteristics of SiCp/LM25 Al Composites Using Goal Programming

    Institute of Scientific and Technical Information of China (English)

    R.Karthikeyan; S. Raju; R.S.Naagarazan; B. C. Pai

    2001-01-01

    In the present study an effort has been made to optimize the machining conditions for electric discharge machining of LM25 Al (7 Si, 0.33 Mg, 0.3 Mn, 0.5 Fe, 0.1 Cu, 0.1 Ni,.2 Ti) reinforced with green bonded SiC particles with approximate size of 25 μm. Polynomial models were developed for the various EDM characteristics such as metal removal rate, tool wear rate and surface roughness in terms of the process parameters such as volume fraction of SiC, current and pulse time. The models were used to optimize the EDM characteristics using nonlinear goal programming.

  18. The General Configuration of CEV1 Electric Vehicle's Electrical System and the Design of Its Control Sequence

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The general configuration of CEV1 electric vehicle's electrical system and the design scheme of its control sequence are presented, which are modularized by using VMU as master control unit, PMU as power management unit, BMU as battery management unit. It is a rather advanced and practical general design scheme of electric vehicle, because the division of its module function is definite, which is advantage for research, manufacture and maintenance.

  19. 数控机床典型电气故障诊断与维修%Diagnosis and Maintenance of Electrical Breakdown of CNC Machine Tools

    Institute of Scientific and Technical Information of China (English)

    张晶辉

    2016-01-01

    With the development of numerical control technology ,the maintenance of CNC machine tools has become increasingly important .A CNC machine tool is mainly composed of electrical ,mechanical and hydraulic components .This paper discussed the diagnosis and maintenance of electrical breakdown of CNC machine tools .Through the understanding of the electrical principle of machine tools ,we can improve the efficience of repair and maintenance of the electrical system of machine tools .%随着数控技术的发展,数控机床的维修已越来越重要。主要对数控机床电气部分的故障诊断与维修进行了介绍。基于对机床电气原理的认识,可以更好地对机床电气系统进行维修与维护。

  20. 15 CFR 700.31 - Metalworking machines.

    Science.gov (United States)

    2010-01-01

    ... Drilling and tapping machines Electrical discharge, ultrasonic and chemical erosion machines Forging..., power driven Machining centers and way-type machines Manual presses Mechanical presses, power...

  1. One-step process for superhydrophobic metallic surfaces by wire electrical discharge machining.

    Science.gov (United States)

    Bae, Won Gyu; Song, Ki Young; Rahmawan, Yudi; Chu, Chong Nam; Kim, Dookon; Chung, Do Kwan; Suh, Kahp Y

    2012-07-25

    We present a direct one-step method to fabricate dual-scale superhydrophobic metallic surfaces using wire electrical discharge machining (WEDM). A dual-scale structure was spontaneously formed by the nature of exfoliation characteristic of Al 7075 alloy surface during WEDM process. A primary microscale sinusoidal pattern was formed via a programmed WEDM process, with the wavelength in the range of 200 to 500 μm. Notably, a secondary roughness in the form of microcraters (average roughness, Ra: 4.16 to 0.41 μm) was generated during the exfoliation process without additional chemical treatment. The low surface energy of Al 7075 alloy (γ = 30.65 mJ/m(2)) together with the presence of dual-scale structures appears to contribute to the observed superhydrophobicity with a static contact angle of 156° and a hysteresis less than 3°. To explain the wetting characteristics on dual-scale structures, we used a simple theoretical model. It was found that Cassie state is likely to present on the secondary roughness in all fabricated surfaces. On the other hand, either Wenzel or Cassie state can present on the primary roughness depending on the characteristic length of sinusoidal pattern. In an optimal condition of the serial cutting steps with applied powers of ∼30 and ∼8 kW, respectively, a stable, superhydrophobic metallic surface was created with a sinusoidal pattern of 500 μm wavelength.

  2. Preliminary Numerical Investigations of Entropy Generation in Electric Machines Based on a Canonical Configuration

    Directory of Open Access Journals (Sweden)

    Toni Eger

    2015-12-01

    Full Text Available The present paper analyzes numerically the entropy generation induced by forced convection in a canonical configuration. The configuration itself includes two well known fluid dynamic problems: (1 an external flow (flow around a cylinder, Kármán flow; and (2 an internal flow (flow between two concentric rotating cylinders, Couette flow. In many daily engineering issues (e.g., cooling of electric machines, a combination of these problems occurs and has to be investigated. Using the canonical configuration, the fields of entropy generation are analyzed in this work for a constant wall heat flux but varying two key parameters (Reynolds numbers Re∞ and Re0. The entropy generation due to conduction shows an absolute minimum around Re0 = 10,000. The same minima can be found by a detailed analysis of the temperature profile. Thus, entropy generation seems to be a suitable indicator for optimizing heat exchange processes and delivers a large amount of information concerning fluid and heat transport.

  3. Analysis of aerosol emission and hazard evaluation of electrical discharge machining (EDM) process.

    Science.gov (United States)

    Jose, Mathew; Sivapirakasam, S P; Surianarayanan, M

    2010-01-01

    The safety and environmental aspects of a manufacturing process are important due to increased environmental regulations and life quality. In this paper, the concentration of aerosols in the breathing zone of the operator of Electrical Discharge Machining (EDM), a commonly used non traditional manufacturing process is presented. The pattern of aerosol emissions from this process with varying process parameters such as peak current, pulse duration, dielectric flushing pressure and the level of dielectric was evaluated. Further, the HAZOP technique was employed to identify the inherent safety aspects and fire risk of the EDM process under different working conditions. The analysis of aerosol exposure showed that the concentration of aerosol was increased with increase in the peak current, pulse duration and dielectric level and was decreased with increase in the flushing pressure. It was also found that at higher values of peak current (7A) and pulse duration (520 micros), the concentration of aerosols at breathing zone of the operator was above the permissible exposure limit value for respirable particulates (5 mg/m(3)). HAZOP study of the EDM process showed that this process is vulnerable to fire and explosion hazards. A detailed discussion on preventing the fire and explosion hazard is presented in this paper. The emission and risk of fire of the EDM process can be minimized by selecting proper process parameters and employing appropriate control strategy.

  4. Rapid and Efficient Synthesis of Silver Nanofluid Using Electrical Discharge Machining

    Directory of Open Access Journals (Sweden)

    Kuo-Hsiung Tseng

    2013-01-01

    Full Text Available The electrical discharge machining (EDM system has been proven feasible as a rapid and efficient method for silver nanofluid preparation. This study prepared the silver nano-fluid via EDM and investigated the relationship between its process parameters and product characteristics. The prior study had found that the silver nano-fluid prepared by EDM contained both silver nanoparticles and silver ions. Silver ions had revealed the cause of the high suspension of the silver nanoparticles. To examine the relationship between the stability of silver nanofluid and the process parameters, this study quantified the relationship of process parameters to the material removal rate (MRR of silver electrode and silver ion output rate (IOR in the fluid, in order to achieve the most effective process parameter condition. Furthermore, the stability of silver nano-fluid was analyzed by various devices, including UV-Vis spectroscopy, size-distribution, and Zeta-potential analyzer. The effects of MRR, IOR, particle size, Zeta-potential, and optical properties of silver nanofluid under different process parameters are also discussed.

  5. Modelling effect of magnetic field on material removal in dry electrical discharge machining

    Science.gov (United States)

    Abhishek, Gupta; Suhas, S. Joshi

    2017-02-01

    One of the reasons for increased material removal rate in magnetic field assisted dry electrical discharge machining (EDM) is confinement of plasma due to Lorentz forces. This paper presents a mathematical model to evaluate the effect of external magnetic field on crater depth and diameter in single- and multiple-discharge EDM process. The model incorporates three main effects of the magnetic field, which include plasma confinement, mean free path reduction and pulsating magnetic field effects. Upon the application of an external magnetic field, Lorentz forces that are developed across the plasma column confine the plasma column. Also, the magnetic field reduces the mean free path of electrons due to an increase in the plasma pressure and cycloidal path taken by the electrons between the electrodes. As the mean free path of electrons reduces, more ionization occurs in plasma column and eventually an increase in the current density at the inter-electrode gap occurs. The model results for crater depth and its diameter in single discharge dry EDM process show an error of 9%-10% over the respective experimental values.

  6. Hydrophobic and oleophobic re-entrant steel microstructures fabricated using micro electrical discharge machining

    Science.gov (United States)

    Weisensee, Patricia B.; Torrealba, Eduardo J.; Raleigh, Mark; Jacobi, Anthony M.; King, William P.

    2014-09-01

    This paper presents the fabrication of metallic micro-mushroom re-entrant structures and the characterization of their hydrophobicity and oleophobicity. Five different microstructure geometries are introduced, with typical feature sizes in the range of 10-100 μm. These microstructures are realized in steel, and are fabricated over the cm-scale using micro electrical discharge machining (mEDM). The liquid repellency of these surfaces is characterized using droplets of either water (surface energy γlg = 72.4 mN m-1), RL-68H oil (γlg = 28.6 mN m-1), or Isopropanol (IPA) (γlg = 21.7 mN m-1). The water droplets form nearly perfect spheres, with contact angles in the range 146-162°, and contact angle hysteresis of 19-35°. The oil droplet contact angles are in the range 106-152° and the IPA contact angles are in the range 75-123°. Strong re-entrant features and close spacing are necessary to support a fully non-wetting state for use with oil and IPA. Water forms the highest contact angles with narrow, post-like, and widely spaced micro-mushroom geometries.

  7. An Extreme Learning Machine Based on the Mixed Kernel Function of Triangular Kernel and Generalized Hermite Dirichlet Kernel

    Directory of Open Access Journals (Sweden)

    Senyue Zhang

    2016-01-01

    Full Text Available According to the characteristics that the kernel function of extreme learning machine (ELM and its performance have a strong correlation, a novel extreme learning machine based on a generalized triangle Hermitian kernel function was proposed in this paper. First, the generalized triangle Hermitian kernel function was constructed by using the product of triangular kernel and generalized Hermite Dirichlet kernel, and the proposed kernel function was proved as a valid kernel function of extreme learning machine. Then, the learning methodology of the extreme learning machine based on the proposed kernel function was presented. The biggest advantage of the proposed kernel is its kernel parameter values only chosen in the natural numbers, which thus can greatly shorten the computational time of parameter optimization and retain more of its sample data structure information. Experiments were performed on a number of binary classification, multiclassification, and regression datasets from the UCI benchmark repository. The experiment results demonstrated that the robustness and generalization performance of the proposed method are outperformed compared to other extreme learning machines with different kernels. Furthermore, the learning speed of proposed method is faster than support vector machine (SVM methods.

  8. 76 FR 11437 - Application To Export Electric Energy; Societe Generale Energy Corp.

    Science.gov (United States)

    2011-03-02

    ... Application To Export Electric Energy; Societe Generale Energy Corp. AGENCY: Office of Electricity Delivery.... (SGEC) has applied for authority to transmit electric energy from the United States to Canada pursuant... application from the SGEC for authority to transmit electric energy from the United States to Canada as...

  9. Comparative study on discharge conditions in micro-hole electrical discharge machining of tungsten carbide (WC-Co) material

    Institute of Scientific and Technical Information of China (English)

    Hyun-Seok TAK; Chang-Seung HA; Dong-Hyun KIM; Ho-Jun LEE; Hae-June LEE; Myung-Chang KANG

    2009-01-01

    WC-Co is used widely in die and mold industries due to its unique combination of hardness, strength and wear-resistance. For machining difficult-to-cut materials, such as tungsten carbide, micro-electrical discharge machining(EDM) is one of the most effective methods for making holes because the hardness is not a dominant parameter in EDM. This paper describes the characteristics of the discharge conditions for micro-hole EDM of tungsten carbide with a WC grain size of 0.5μm and Co content of 12%. The EDM process was conducted by varying the condenser and resistance values. A R-C discharge EDM device using arc erosion for micro-hole machining was suggested. Furthermore, the characteristics of the developed micro-EDM were analyzed in terms of the electro-optical observation using an oscilloscope and field emission scanning electron microscope.

  10. Experiments of Micro-Electrical Discharge Machining%微细电火花加工的实验研究

    Institute of Scientific and Technical Information of China (English)

    张勇斌; 吉方; 刘广民; 张连新; 吴祉群

    2011-01-01

    Some t ypical experiments of micro-electrical discharge machining are described based on a set of new developed micro-eiectrical discharge machining equipment typed μEDM-50 in the paper.The resuhs about micro-character precise machining and discharging deposition are given. The size of the rnachining character varies mainly from a few decades of micrometers to a few millimeters.%基于新研发的一套微细电火花精密加工系统EDM-50,在金属材料上进行了一些典型的微小特征精密加工实验及电火花放电沉积实验.该系统已作为加工特征尺寸介于数十微米到数毫米范围的重要工艺手段.

  11. A novel design of DC-AC electrical machine rotary converter for hybrid solar and wind energy applications

    Science.gov (United States)

    Mohammed, K. G.; Ramli, A. Q.; Amirulddin, U. A. U.

    2013-06-01

    This paper proposes the design of a new bi-directional DC-AC rotary converter machine to convert a d.c. voltage to three-phase voltage and vice-versa using a two-stage energy conversion machine. The rotary converter consists of two main stages which are combined into single frame. These two stages are constructed from three main electromagnetic components. The first inner electromagnetic component represents the input stage that enables the DC power generated by solar energy from photo-voltaic cells to be transformed by the second and third components electro-magnetically to produce multi-phase voltages at the output stage. At the same time, extra kinetic energy from wind, which is sufficiently available, can be added to existing torque on the second electromagnetic component. Both of these input energies will add up to the final energy generated at the output terminals. Therefore, the machine will be able to convert solar and wind energies to the output terminals simultaneously. If the solar energy is low, the available wind energy will be able to provide energy to the output terminals and at the same time charges the batteries which are connected as backup system. At this moment, the machine behaves as wind turbine. The energy output from the machine benefits from two energy sources which are solar and wind. At night when the solar energy is not available and also the load is low, the wind energy is able to charge the batteries and at the same time provides output electrical power to the remaining the load. Therefore, the proposed system will have high usage of available renewable energy as compared to separated wind or solar systems. MATLAB codes are used to calculate the required dimensions, the magnetic and electrical circuits parameters to design of the new bi-directional rotary converter machine.

  12. An experimental study on the effect of parameters on the depth of crater machined by electrostatic field–induced electrolyte jet micro electrical discharge machining

    Directory of Open Access Journals (Sweden)

    Yaou Zhang

    2016-04-01

    Full Text Available Electrostatic field–induced electrolyte jet micro electrical discharge machining depends on heat generated by the periodic pulsed discharge between the workpiece and the electrolyte fine jet from the tip of Taylor cone, induced by the intense electric field, to erode the material from the workpiece. To further investigate the characteristics of this discharge process, with the NaCl solution as the electrostatic field–induced electrolyte jet electrolyte and the silicon wafer as the workpiece, the governing factors of machining polarity, nozzle-to-workpiece distance, voltage applied between positive and negative polarities, and the effect of concentration of the electrolyte on the depth of crater after a single electrostatic field–induced electrolyte jet discharge have been studied. The experimental results show that the average depth of crater increases with the increase in the voltage applied between the nozzle and the workpiece, and increases with the increase in the concentration of the electrolyte, but decreases with the increase in the distance between the nozzle and the workpiece. The results have also demonstrated that the polarity has no clear influence on the average depth of crater after a single discharge.

  13. Effect of Micro Electrical Discharge Machining Process Conditions on Tool Wear Characteristics: Results of an Analytic Study

    DEFF Research Database (Denmark)

    Puthumana, Govindan; P., Rajeev

    2016-01-01

    Micro electrical discharge machining is one of the established techniques to manufacture high aspect ratio features on electrically conductive materials. This paper presents the results and inferences of an analytical study for estimating theeffect of process conditions on tool electrode wear...... characteristicsin micro-EDM process. A new approach with two novel factors anticipated to directly control the material removal mechanism from the tool electrode are proposed; using discharge energyfactor (DEf) and dielectric flushing factor (DFf). The results showed that the correlation between the tool wear rate...

  14. Strategies of General.Electric company's Development

    Institute of Scientific and Technical Information of China (English)

    杨娜

    2016-01-01

    As the biggest multinational corporate providing technology and services, the success of General Electric (GE) is always used for reference by other companies. This report is to evaluate the suitability of GE's strategic position from 2001 to early 2014. After a brief company overview, the report first points out current strategies which GE applies and analyses GE's activities with strategy concepts such as Porter's generic strategy and' Ansoff matrix. Strategic position analysis consists pf environmental analysis, capability analysis and stakeholders' expectations and purposes. GE's environmental analysis is drawn from macro-environment with PEST analysis and micro-environment with Porter's five forces analysis, and opportunities and threats are evaluated based on that. After that, the report introduces resources deployed by GE and therefore outlines the strengths and weakness of GE's strategy. Following GE's capability analysis, the stakeholders' power distribution and purposes part describes corporate governance, stakeholders' expectation and CSR to illustrate how GE's strategies are affected by stakeholder's exnectations.

  15. Processing and Characterization of Novel Biomimetic Nanoporous Bioceramic Surface on β-Ti Implant by Powder Mixed Electric Discharge Machining

    Science.gov (United States)

    Prakash, Chander; Kansal, H. K.; Pabla, B. S.; Puri, Sanjeev

    2015-09-01

    Herein, a β-Ti-based implant was subjected to powder mixed electric discharge machining (PMEDM) for surface modification to produce a novel biomimetic nanoporous bioceramic surface. The microstructure, surface topography, and phase composition of the non-machined and machined (PMEDMed) surfaces were investigated using field-emission scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffraction. The microhardness of the surfaces was measured on a Vickers hardness tester. The corrosion resistance of the surfaces was evaluated via potentiodynamic polarization measurements in simulated body fluid. The application of PMEDM not only altered the surface chemistry, but also imparted the surface with a nanoporous topography or a natural bone-like surface structure. The characterization results confirmed that the alloyed layer mainly comprised bioceramic oxides and carbide phases (TiO2, Nb2O5, ZrO2, SiO2, TiC, NbC, SiC). The microhardness of PMEDMed surface was twofold higher than that of the base material (β-Ti alloy), primarily because of the formation of the hard carbide phases on the machined layer. Electrochemical analysis revealed that PMEDMed surface featured insulative and protective properties and thus displayed higher corrosion resistance ability when compared with the non-machined surface. This result was attributed to the formation of the bioceramic oxides on the machined surface. Additionally, the in vitro biocompatibility of the surfaces was evaluated using human osteoblastic cell line MG-63. PMEDMed surface with a micro-, sub-micro-, and nano-structured topography exhibited bioactivity and improved biocompatibility relative to β-Ti surface. Furthermore, PMEDMed surface enabled better adhesion and growth of MG-63 when compared with the non-machined substrate.

  16. Laser machining of advanced materials

    CERN Document Server

    Dahotre, Narendra B

    2011-01-01

    Advanced materialsIntroductionApplicationsStructural ceramicsBiomaterials CompositesIntermetallicsMachining of advanced materials IntroductionFabrication techniquesMechanical machiningChemical Machining (CM)Electrical machiningRadiation machining Hybrid machiningLaser machiningIntroductionAbsorption of laser energy and multiple reflectionsThermal effectsLaser machining of structural ceramicsIntrodu

  17. Use of fiber optic-based distributed temperature measurement system for electrical machines

    Science.gov (United States)

    Rajendran, Veera P.; Deblock, Mark; Wetzel, Todd; Lusted, Mark; Kaminski, Christopher; Childers, Brooks A.

    2003-11-01

    A fiber optic based distributed temperature measurement system was implemented in stator windings (straight copper bars) as well as in the end-windings (curved copper bars) of a motor. Usually, in electrical machines such as motors or generators, only a few conventional temperature sensors are used, whereas the distributed temperature system has the potential of providing very detailed temperature distribution by having hundreds of sensors in a single fiber. The sensors were made of Bragg gratings etched onto the fiber itself. For the present study, the spatial resolution of the sensors is 6 mm (nominally at 1/4" apart). The technique uses Optical Frequency Domain Reflectometry (OFDR) to process the back-reflected light signal indicative of the thermal filed. A prototype fiber optic system was implemented in a motor made by GE industrial systems. The sensing length (length of the stator) for the motor was 0.75 m containing approximately 150 sensors thus providing very detailed temperature data. Performance tests were conducted at different heat loads representing different electrical conditions. Continuous tests for the duration of 19 hours were conducted. The temperature of stator windings varied from ambient (~ 23°C) to approximately 85°C. As reference, Resistance Temperature Devices (RTDs) were installed in adjacent slots to the slot where fiber optic sensors were installed. A total of 8 sensors were installed but data were collected on only 3 fibers. Fiber sensor measurements were found to track the temperature trends very well. The fiber data agreed with RTD data within +/- 3°C in the entire duration. The RMS value of difference between the fiber and RTD on one side was 0.3°C, and with the RTD on the other side was 0.5°C. The fiber measurements also showed how hotspots could be missed by using few RTDs, as is done in the industry. The fiber measurements also showed the temperature distribution in the endwindings, an area not normally monitored. The

  18. A generalization information management system applied to electrical distribution

    Energy Technology Data Exchange (ETDEWEB)

    Geisler, K.I.; Neumann, S.A.; Nielsen, T.D.; Bower, P.K. (Empros Systems International (US)); Hughes, B.A.

    1990-07-01

    This article presents a system solution approach that meets the requirements being imposed by industry trends and the electric utility customer. Specifically, the solution addresses electric distribution management systems. Electrical distribution management is a particularly well suited area of application because it involves a high diversity of tasks, which are currently supported by a proliferation of automated islands. Islands of automation which currently exist include (among others) distribution operations, load management, automated mapping, facility management, work order processing, and planning.

  19. Sustainable Micro-Manufacturing of Micro-Components via Micro Electrical Discharge Machining

    Directory of Open Access Journals (Sweden)

    Valeria Marrocco

    2011-12-01

    Full Text Available Micro-manufacturing emerged in the last years as a new engineering area with the potential of increasing peoples’ quality of life through the production of innovative micro-devices to be used, for example, in the biomedical, micro-electronics or telecommunication sectors. The possibility to decrease the energy consumption makes the micro-manufacturing extremely appealing in terms of environmental protection. However, despite this common belief that the micro-scale implies a higher sustainability compared to traditional manufacturing processes, recent research shows that some factors can make micro-manufacturing processes not as sustainable as expected. In particular, the use of rare raw materials and the need of higher purity of processes, to preserve product quality and manufacturing equipment, can be a source for additional environmental burden and process costs. Consequently, research is needed to optimize micro-manufacturing processes in order to guarantee the minimum consumption of raw materials, consumables and energy. In this paper, the experimental results obtained by the micro-electrical discharge machining (micro-EDM of micro-channels made on Ni–Cr–Mo steel is reported. The aim of such investigation is to shed a light on the relation and dependence between the material removal process, identified in the evaluation of material removal rate (MRR and tool wear ratio (TWR, and some of the most important technological parameters (i.e., open voltage, discharge current, pulse width and frequency, in order to experimentally quantify the material waste produced and optimize the technological process in order to decrease it.

  20. Electric and Weak Electric Dipole Form Factors for Heavy Fermions in a General Two Higgs Doublet Model

    CERN Document Server

    Gómez-Dumm, D; Gomez-Dumm, Daniel

    1999-01-01

    The electric and weak electric dipole form factors for heavy fermions are calculated in the context of the most general two-Higgs-doublet model (2HDM). We find that the large top mass can produce a significant enhancement of the electric dipole form factor in the case of the b and c quarks. This effect can be used to distinguish between different 2HDM scenarios.

  1. The use of machine learning algorithms to design a generalized simplified denitrification model

    Science.gov (United States)

    Oehler, F.; Rutherford, J. C.; Coco, G.

    2010-10-01

    We propose to use machine learning (ML) algorithms to design a simplified denitrification model. Boosted regression trees (BRT) and artificial neural networks (ANN) were used to analyse the relationships and the relative influences of different input variables towards total denitrification, and an ANN was designed as a simplified model to simulate total nitrogen emissions from the denitrification process. To calibrate the BRT and ANN models and test this method, we used a database obtained collating datasets from the literature. We used bootstrapping to compute confidence intervals for the calibration and validation process. Both ML algorithms clearly outperformed a commonly used simplified model of nitrogen emissions, NEMIS, which is based on denitrification potential, temperature, soil water content and nitrate concentration. The ML models used soil organic matter % in place of a denitrification potential and pH as a fifth input variable. The BRT analysis reaffirms the importance of temperature, soil water content and nitrate concentration. Generalization, although limited to the data space of the database used to build the ML models, could be improved if pH is used to differentiate between soil types. Further improvements in model performance and generalization could be achieved by adding more data.

  2. The use of machine learning algorithms to design a generalized simplified denitrification model

    Directory of Open Access Journals (Sweden)

    F. Oehler

    2010-04-01

    Full Text Available We designed generalized simplified models using machine learning algorithms (ML to assess denitrification at the catchment scale. In particular, we designed an artificial neural network (ANN to simulate total nitrogen emissions from the denitrification process. Boosted regression trees (BRT, another ML was also used to analyse the relationships and the relative influences of different input variables towards total denitrification. To calibrate the ANN and BRT models, we used a large database obtained by collating datasets from the literature. We developed a simple methodology to give confidence intervals for the calibration and validation process. Both ML algorithms clearly outperformed a commonly used simplified model of nitrogen emissions, NEMIS. NEMIS is based on denitrification potential, temperature, soil water content and nitrate concentration. The ML models used soil organic matter % in place of a denitrification potential and pH as a fifth input variable. The BRT analysis reaffirms the importance of temperature, soil water content and nitrate concentration. Generality of the ANN model may also be improved if pH is used to differentiate between soil types. Further improvements in model performance can be achieved by lessening dataset effects.

  3. Calculation of the electric field gradients, generalized Sternheimer shielding constants, and electric-field-gradient polarizabilities for ten small molecules

    Science.gov (United States)

    Bishop, David M.; Cybulski, sławomir M.

    1994-05-01

    Electric field gradients, generalized Sternheimer shielding constants, and electric-field-gradient polarizabilities are calculated for H2, N2, F2, HF, HCl, CO, HCN, HNC, H2O, and NH3. The calculations are performed at both the Hartree-Fock and second order Møller-Plesset levels of approximation using large basis sets. For most of these molecules this is the first time that the shielding constants and electric field gradient polarizabilities have been determined. Electron correlation is generally found to be a significant factor.

  4. Analog models of computations \\& Effective Church Turing Thesis: Efficient simulation of Turing machines by the General Purpose Analog Computer

    CERN Document Server

    Pouly, Amaury; Graça, Daniel S

    2012-01-01

    \\emph{Are analog models of computations more powerful than classical models of computations?} From a series of recent papers, it is now clear that many realistic analog models of computations are provably equivalent to classical digital models of computations from a \\emph{computability} point of view. Take, for example, the probably most realistic model of analog computation, the General Purpose Analog Computer (GPAC) model from Claude Shannon, a model for Differential Analyzers, which are analog machines used from 1930s to early 1960s to solve various problems. It is now known that functions computable by Turing machines are provably exactly those that are computable by GPAC. This paper is about next step: understanding if this equivalence also holds at the \\emph{complexity} level. In this paper we show that the realistic models of analog computation -- namely the General Purpose Analog Computer (GPAC) -- can simulate Turing machines in a computationally efficient manner. More concretely we show that, modulo...

  5. Machine Learning Algorithms for Smart Electricity Markets : Essays on autonomous electricity broker design, probabilistic preference modeling, and competitive benchmarking

    NARCIS (Netherlands)

    M. Peters (Markus)

    2015-01-01

    markdownabstract__Abstract__ The shift towards sustainable electricity systems is one of the grand challenges of the twenty-first century. Decentralized production from renewable sources, electric mobility, and related advances are at odds with traditional power systems where central large-scale ge

  6. Modeling and Control of a Flux-Modulated Compound-Structure Permanent-Magnet Synchronous Machine for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Zhiyi Song

    2012-01-01

    Full Text Available The compound-structure permanent-magnet synchronous machine (CS-PMSM, comprising a double rotor machine (DRM and a permanent-magnet (PM motor, is a promising electronic-continuously variable transmission (e-CVT concept for hybrid electric vehicles (HEVs. By CS-PMSM, independent speed and torque control of the vehicle engine is realized without a planetary gear unit. However, the slip rings and brushes of the conventional CS-PMSM are considered a major drawback for vehicle application. In this paper, a brushless flux-modulated CS-PMSM is investigated. The operating principle and basic working modes of the CS-PMSM are discussed. Mathematical models of the CS-PMSM system are given, and joint control of the two integrated machines is proposed. As one rotor of the DRM is mechanically connected with the rotor of the PM motor, special rotor position detection and torque allocation methods are required. Simulation is carried out by Matlab/Simulink, and the feasibility of the control system is proven. Considering the complexity of the controller, a single digital signal processor (DSP is used to perform the interconnected control of dual machines instead of two separate ones, and a typical hardware implementation is proposed.

  7. Effect of dielectric fluid with surfactant and graphite powder on Electrical Discharge Machining of titanium alloy using Taguchi method

    Directory of Open Access Journals (Sweden)

    Murahari Kolli

    2015-12-01

    Full Text Available In this paper, Taguchi method was employed to optimize the surfactant and graphite powder concentration in dielectric fluid for the machining of Ti-6Al-4V using Electrical Discharge Machining (EDM. The process parameters such as discharge current, surfactant concentration and powder concentration were changed to explore their effects on Material Removal Rate (MRR, Surface Roughness (SR, Tool wear rate (TWR and Recast Layer Thickness (RLT. Detailed analysis of structural features of machined surface was carried out using Scanning Electron Microscope (SEM to observe the influence of surfactant and graphite powder on the machining process. It was observed from the experimental results that the graphite powder and surfactant added dielectric fluid significantly improved the MRR, reduces the SR, TWR and RLT at various conditions. Analysis of Variance (ANOVA and F-test of experimental data values related to the important process parameters of EDM revealed that discharge current and surfactant concentration has more percentage of contribution on the MRR and TWR whereas the SR, and RLT were found to be affected greatly by the discharge current and graphite powder concentration.

  8. Micro-CT evaluation of in vivo osteogenesis at implants processed by wire-type electric discharge machining.

    Science.gov (United States)

    Yamaki, Koichi; Kataoka, Yu; Ohtsuka, Fukunaga; Miyazaki, Takashi

    2012-01-01

    Titanium surfaces processed by wire-type electric discharge machining (EDM) are microfabricated surfaces with an irregular morphology, and they exhibited excellent in vitro bone biocompatibility. In this study, the efficiency of in vivo osteogenesis on EDM surfaces was investigated by surgically placing screw-shaped EDM-processed and machined-surface implants into the femurs of four Japanese white rabbits. The volume and process of new bone formation were evaluated by an X-ray micro-CT scanner, coupled with histopathological observations at 1, 2, and 4 weeks post-implantation. Before surgical implantation, the surface topography and contact angle of each implant surface were examined. Bone formation increased over time on both implant surfaces, with both implant types yielding statistically equivalent bone volume at 4 weeks post-implementation. However, at 1 week post-implantation, amount of new bone at EDM-processed implant was markedly greater than that at machined-surface implant. Moreover, new bone appeared to initiate directly from the EDM surfaces, while new bone appeared to generate from pre-existing host bone to the machined surfaces. Thus, EDM seemed to be a promising method for surface modification of titanium implants to support enhanced osteogenesis.

  9. INVESTIGATION OF SURFACE PROPERTIES IN MANGANESE POWDER MIXED ELECTRICAL DISCHARGE MACHINING OF OHNS AND D2 DIE STEELS

    Directory of Open Access Journals (Sweden)

    S. Kumar

    2010-12-01

    Full Text Available The electrical discharge machining (EDM process is used for generating accurate internal profiles in hardened materials. An powder additive in the hydrocarbon dielectric affects the energy distribution and sparking efficiency, and consequently the surface finish and micro-hardness. In this paper the Taguchi approach has been used to optimize and compare the surface properties in manganese powder-mixed EDM of oil-hardening non-shrinkable (OHNS and high-carbon high-chromium (D2 die steels. The results of the study show an improvement of 73% and 71.6% in the micro-hardness of OHNS and D2 die steels, respectively. The machining parameters for the best value of micro-hardness are found to be the same for both work materials. A scanning electron microscopy and X-ray diffraction analysis of the machined surfaces show a transfer of manganese and carbon from the plasma channel in the form of manganese carbide. The chemical composition of the machined surface has been further checked on an optical emission spectrometer to verify and quantify the results.

  10. Electrically Driven General Systems for UAV’s

    Science.gov (United States)

    2007-11-01

    systems are discussed in this paper. First the Barracuda M-05 UAV Demonstrator and second the 270 VDC More Electric Aircraft project launched by the...German Federal Office of Defense Technology and Procurement (BWB). 3.1 Barracuda M-05 The Barracuda M-05 is a company founded unmanned...test flight. Figure 4 showed a picture of the first flight. Figure 4: Barracuda M-05 First Flight With respect to electrically driven

  11. Comparison of PMAC Machines for Starter-Generator Application in a Series Hybrid-Electric Bus

    OpenAIRE

    Sinisa Jurkovic; Strangas, Elias G.

    2011-01-01

    This paper presents a comparative study of outer rotor PMAC machine candidates for starter-generator application in hybrid bus with series power train configuration. PMAC machines with interior and surface mount permanent magnets are considered and compared, although a complete analysis is only carried out for the SPM. Different design aspects such as concentrated versus distributed windings as well as interior and exterior rotor structures are evaluated. Different slot numbers per p...

  12. Development of a perpendicular vibration-induced electrical discharge machining process for fabrication of partially wavy inner structures

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju Chul; Park, Sang Hu; Min, June Kee; Ha, Man Yeong; Shin, Bo Sung [Pusan National University, Busan (Korea, Republic of); Cho, Jong Rae [Korea Maritime University, Busan (Korea, Republic of)

    2016-05-15

    Heat transfer enhancement is an important issue in energy systems. To improve the efficiency of a cooling channel used inside injection molds, turbine blades, and high-temperature devices, channels with various shapes, such as wavy, elliptical, and twisted, have been studied. A cooling channel with a partially wavy inner structure has shown outstanding cooling performance despite a small increase in friction factor. However, generating a partially wavy inner structure inside a channel through conventional machining processes is not easy. To address this problem, we developed a new process called Perpendicular vibration-induced electrical discharge machining (PV-EDM). A specific electrode and one- and random-directional vibrating devices controlled by a pneumatic load were designed for the PV-EDM process. Experimental results showed that local shaping on the inner wall of a channel is possible, which confirmed the possibility of application of this process to actual industrial problems.

  13. Study on mild and severe wear of 7075 aluminum alloys by high-speed wire electrical discharge machining

    Science.gov (United States)

    Xu, Jinkai; Qiu, Rongxian; Xia, Kui; Wang, Zhichao; Xu, Lining; Yu, Huadong

    2017-01-01

    The recast and the carbon layers were fabricated on 7075Al alloys surface by the high-speed wire electrical discharge machining (HS-WEDM) technologyunder various working parameters. The mechanical properties and friction behaviors of the layers were investigated by UMT. 7075 Al alloys were used to do dry sliding wear tests on a pin-ondisk wear tester at room temperature under various contact pressures. 7075 Al alloys had almost the same wear regularity as a function of sliding velocity and rated frequency. The hardness of recast layer was improved. And this method can enhance durability of 7075 Al alloy effectively.The transition to severe wear occurred at a higher load (12N) for asmachined samples, compared with 7075 matrix (9N), the as-machined samples exhibited lower wear rates within the tested loading range.

  14. Joint punching and frequency effects on practical magnetic characteristics of electrical steels for high-speed machines

    Science.gov (United States)

    Kedous-Lebouc, A.; Messal, O.; Youmssi, A.

    2017-03-01

    Mechanical punching of electrical steels causes a degradation of their magnetic characteristics which can extend several millimeters from the cut edge. So, in the field of industrial applications, particularly that of small electrical machines, the stator core made of rigid and thin teeth would be subject to more losses. Thus, this topic of the effect of punching has to be submitted to further deep characterization and development in order to give some insight into the different mechanisms. In this framework, this paper evaluates the combined effect of punching and frequency on the magnetization curve and iron losses in thin SiFe and CoFe soft magnetic sheets. These alloys are typically suitable for the manufacture of high-speed electrical machines used in on board applications (aircraft power generators, automotive, etc). Two SiFe alloys and a CoFe alloy have been investigated. First, different rectangular samples of variable width (15, 10, 5, 3 mm) have been industrially punched. Then, a dedicated magnetic characterization has been made, using basically a mini-Epstein frame. Measurements have been performed from 50 Hz to 1 kHz and from 0.3 T to near saturation. Both rolling and transverse directions have been considered. Finally, a first attempt to predict the degradation due to the punching is presented. A useful description of the magnetic permeability as a function of B and f is given and the degradation parameters are estimated based on the knowledge of the reference permeability.

  15. Current Type of Electrical Discharge Machining Pulse Generator%电流型电火花加工脉冲电源的研究

    Institute of Scientific and Technical Information of China (English)

    宋博岩; 赵万生; 邵革良

    2001-01-01

    In this paper, the disadvantages of traditional independent type of electrical discharge machining pulse generator and inverter electrical discharge machining pulse generator are analyzed, and then the principle of current type of electrical discharge machining pulse generator is proposed for the first time. A large quantity of contrast tests between current type of electrical discharge machining pulse generator and traditional independent type of electrical discharge machining pulse generator show that the current type is not only high efficient energy-saving, but also meet the needs of machining performances.%分析了传统独立式电火花加工脉冲电源和逆变式电火花加工脉冲电源的不足,论述了电流型电火花加工脉冲电源的工作原理。大量的样机和独立式脉冲电源的对比工艺试验表明,电流型脉冲电源不仅满足了电火花加工多项性能指标的要求,而且达到了高效节能的效果。

  16. The PennBMBI: Design of a General Purpose Wireless Brain-Machine-Brain Interface System.

    Science.gov (United States)

    Liu, Xilin; Zhang, Milin; Subei, Basheer; Richardson, Andrew G; Lucas, Timothy H; Van der Spiegel, Jan

    2015-04-01

    In this paper, a general purpose wireless Brain-Machine-Brain Interface (BMBI) system is presented. The system integrates four battery-powered wireless devices for the implementation of a closed-loop sensorimotor neural interface, including a neural signal analyzer, a neural stimulator, a body-area sensor node and a graphic user interface implemented on the PC end. The neural signal analyzer features a four channel analog front-end with configurable bandpass filter, gain stage, digitization resolution, and sampling rate. The target frequency band is configurable from EEG to single unit activity. A noise floor of 4.69 μVrms is achieved over a bandwidth from 0.05 Hz to 6 kHz. Digital filtering, neural feature extraction, spike detection, sensing-stimulating modulation, and compressed sensing measurement are realized in a central processing unit integrated in the analyzer. A flash memory card is also integrated in the analyzer. A 2-channel neural stimulator with a compliance voltage up to ± 12 V is included. The stimulator is capable of delivering unipolar or bipolar, charge-balanced current pulses with programmable pulse shape, amplitude, width, pulse train frequency and latency. A multi-functional sensor node, including an accelerometer, a temperature sensor, a flexiforce sensor and a general sensor extension port has been designed. A computer interface is designed to monitor, control and configure all aforementioned devices via a wireless link, according to a custom designed communication protocol. Wireless closed-loop operation between the sensory devices, neural stimulator, and neural signal analyzer can be configured. The proposed system was designed to link two sites in the brain, bridging the brain and external hardware, as well as creating new sensory and motor pathways for clinical practice. Bench test and in vivo experiments are performed to verify the functions and performances of the system.

  17. Development and validation of a general-purpose ASIC chip for the control of switched reluctance machines

    Energy Technology Data Exchange (ETDEWEB)

    Chen Haijin [National ASIC System Engineering Research Center, Southeast University, Nanjing 210096 (China); Jiang-Su Provincial Key Lab of ASIC Design, Nantong University, Nantong 226019 (China)], E-mail: chen.hj@ntu.edu.cn; Lu Shengli; Shi Longxing [National ASIC System Engineering Research Center, Southeast University, Nanjing 210096 (China)

    2009-03-15

    A general-purpose application specific integrated circuit (ASIC) chip for the control of switched reluctance machines (SRMs) was designed and validated to fill the gap between the microcontroller capability and the controller requirements of high performance switched reluctance drive (SRD) systems. It can be used for the control of SRM running either in low speed or in high-speed, i.e., either in chopped current control (CCC) mode or in angular position control (APC) mode. Main functions of the chip include filtering and cycle calculation of rotor angular position signals, commutation logic according to rotor cycle and turn-on/turn-off angles ({theta}{sub on}/{theta}{sub off}), controllable pulse width modulation (PWM) waveforms generation, chopping control with adjustable delay time, and commutation control with adjustable delay time. All the control parameters of the chip are set online by the microcontroller through a serial peripheral interface (SPI). The chip has been designed with the standard cell based design methodology, and implemented in the central semiconductor manufacturing corporation (CSMC) 0.5 {mu}m complementary metal-oxide-semiconductor (CMOS) process technology. After a successful automatic test equipment (ATE) test using the Nextest's Maverick test system, the chip was further validated through an experimental three-phase 6/2-pole SRD system. Both the ATE test and experimental validation results show that the chip can meet the control requirements of high performance SRD systems, and simplify the controller construction. For a resolution of 0.36 deg. (electrical degree), the chip's maximum processable frequency of the rotor angular position signals is 10 kHz, which is 300,000 rev/min when a three-phase 6/2-pole SRM is concerned.

  18. Development and validation of a general-purpose ASIC chip for the control of switched reluctance machines

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hai-Jin [National ASIC System Engineering Research Center, Southeast University, Nanjing 210096 (China)]|[Jiang-Su Provincial Key Lab of ASIC Design, Nantong University, Nantong 226019 (China); Lu, Sheng-Li; Shi, Long-Xing [National ASIC System Engineering Research Center, Southeast University, Nanjing 210096 (China)

    2009-03-15

    A general-purpose application specific integrated circuit (ASIC) chip for the control of switched reluctance machines (SRMs) was designed and validated to fill the gap between the microcontroller capability and the controller requirements of high performance switched reluctance drive (SRD) systems. It can be used for the control of SRM running either in low speed or in high-speed, i.e., either in chopped current control (CCC) mode or in angular position control (APC) mode. Main functions of the chip include filtering and cycle calculation of rotor angular position signals, commutation logic according to rotor cycle and turn-on/turn-off angles ({theta}{sub on}/{theta}{sub off}), controllable pulse width modulation (PWM) waveforms generation, chopping control with adjustable delay time, and commutation control with adjustable delay time. All the control parameters of the chip are set online by the microcontroller through a serial peripheral interface (SPI). The chip has been designed with the standard cell based design methodology, and implemented in the central semiconductor manufacturing corporation (CSMC) 0.5 {mu}m complementary metal-oxide-semiconductor (CMOS) process technology. After a successful automatic test equipment (ATE) test using the Nextest's Maverick test system, the chip was further validated through an experimental three-phase 6/2-pole SRD system. Both the ATE test and experimental validation results show that the chip can meet the control requirements of high performance SRD systems, and simplify the controller construction. For a resolution of 0.36 (electrical degree), the chip's maximum processable frequency of the rotor angular position signals is 10 kHz, which is 300,000 rev/min when a three-phase 6/2-pole SRM is concerned. (author)

  19. Application of combined technology of mechanical machining and electrical discharge machining in manufacturing of impeller%机械加工和电火花加工的组合技术在叶轮制造中的应用

    Institute of Scientific and Technical Information of China (English)

    金玉淑

    2013-01-01

    This paper introduces the application of combined technology of mechanical machining and electrical discharge machining in the manufacturing of narrow path closed-type impeller,it can be fully proved by the test comparison that the combined machining technology is a effective solution to the low machining efficiency of EDM and the interference problem of mechanical machining.%介绍了机械加工和电火花加工的组合技术在窄流道闭式叶轮制造中的应用,通过对比试验可以充分证明,这种组合加工技术是电火花加工效率低、机械加工有干涉等问题的有效解决方法。

  20. 78 FR 47235 - Airworthiness Directives; General Electric Company Turbofan Engines

    Science.gov (United States)

    2013-08-05

    ... Electric Company (GE) model GEnx-2B67 and GEnx-2B67B turbofan engines. This proposed AD was prompted by the... in Boeing 747-8 flight tests had consumed more cyclic life than they would have in revenue flight cycles. These parts were then installed into engines and introduced into revenue service...

  1. Euler-Lagrange models with complex currents of three-phase electrical machines

    CERN Document Server

    Basic, Duro; Rouchon, Pierre

    2008-01-01

    A Lagrangian formulation with complex currents is developed and yields a direct and simple method for modeling three-phases permanent-magnet and induction machines. The Lagrangian is the sum of the mechanical kinetic energy and of the magnetic energy. This magnetic energy is expressed in terms of rotor angle, complex stator and rotor currents. Such Lagrangian setting is a precious guide for modeling space-harmonics and saturation effects. A complexification procedure is applied here in order to derive the Euler-Lagrange equations with complex stator and rotor currents. Such complexification process avoids the usual separation into real and imaginary parts and simplifies notably the calculations. Via simple modification of magnetic energies we derive non-trivial dynamical models describing permanent-magnet machines with both saturation and saliency, and induction machines with both saturation and space harmonics.

  2. Design of a high-torque machine with two integrated motors axes reducing the electric vehicle consumption

    Directory of Open Access Journals (Sweden)

    M. Chaieb

    2008-03-01

    Full Text Available The motorization of electric vehicle needs to work at a constant power on a wide range of speed. In order to be able to satisfy these requirements, we describe in this paper a solution, which consists in modifying of a simple structure of a permanent magnet motor by a double rotor structure integrating two motor axes into the same machine. This article describes, then, a design methodology of a permanent magnet motor with double rotor, radial flux, and strong starting torque for electric vehicles. This work consists on the analytical dimensioning of the motor by taking into account several operation constraints followed by a modelling by the finite elements method. This study is followed by the comparison between this motor and a motor with one rotor. A global model of the motor- converter is developed for the purpose to answer several optimisation problems

  3. Modeling and optimization of process variables of wire-cut electric discharge machining of super alloy Udimet-L605

    Directory of Open Access Journals (Sweden)

    Somvir Singh Nain

    2017-02-01

    Full Text Available This paper presents the behavior of Udimet-L605 after wire electric discharge machining and evaluating the WEDM process using sophisticated machine learning approaches. The experimental work is depicted on the basis of Taguchi orthogonal L27 array, considering six input variables and three interactions. Three models such as support vector machine algorithms based on PUK kernel, non-linear regression and multi-linear regression have been proposed to examine the variance between experimental and predicted outcome and preferred the preeminent model based on its evaluation parameters performance and graph analysis. The grey relational analysis is the relevant approach to obtain the best grouping of input variables for maximum material removal rate and minimum surface roughness. Based on statistical analysis, it has been concluded that pulse-on time, interaction between pulse-on time x pulse-off time, spark-gap voltage and wire tension are the momentous variable for surface roughness while the pulse-on time, spark-gap voltage and pulse-off time are the momentous variables for material removal rate. The micro structural and compositional changes on the surface of work material were examined by means of SEM and EDX analysis. The thickness of the white layer and the recast layer formation increases with increases in the pulse-on time duration.

  4. Electrical discharge machining (EDM) of Inconel 718 by using copper electrode at higher peak current and pulse duration

    Science.gov (United States)

    Ahmad, S.; Lajis, M. A.

    2013-12-01

    This experimental work is an attempt to investigate the performance of Copper electrode when EDM of Nickel Based Super Alloy, Inconel 718 is at higher peak current and pulse duration. Peak current, Ip and pulse duration (pulse on-time), ton are selected as the most important electrical pulse parameters. In addition, their influence on material removal rate (MRR), electrode wear rate (EWR), and surface roughness (Ra) are experimentally investigated. The ranges of 10 mm diameter of Copper electrode are used to EDM of Inconel 718. After the experiments, MRR, EWR, and Ra of the machined surfaces need to be measured in order to evaluate the performance of the EDM process. In order to obtain high MRR, higher peak current in range of 20A to 40A and pulse duration in range of 200μs to 400μs were used. Experimental results have shown that machining at a highest peak current used of 40A and the lowest pulse duration of 200μs used for the experiment yields the highest material removal rate (MRR) with value 34.94 mm3/min, whereas machining at a peak current of 20A and pulse duration of 400μs yields the lowest electrode wear rate (EWR) with value -0.0101 mm3/min. The lowest surface roughness (Ra) is 8.53 μm achieved at a lowest peak current used of 20A and pulse duration of 200μs.

  5. A Review of Additive Mixed-Electric Discharge Machining: Current Status and Future Perspectives for Surface Modification of Biomedical Implants

    Directory of Open Access Journals (Sweden)

    Abdul’Azeez Abdu Aliyu

    2017-01-01

    Full Text Available Surface treatment remained a key solution to numerous problems of synthetic hard tissues. The basic methods of implant surface modification include various physical and chemical deposition techniques. However, most of these techniques have several drawbacks such as excessive cost and surface cracks and require very high sintering temperature. Additive mixed-electric discharge machining (AM-EDM is an emerging technology which simultaneously acts as a machining and surface modification technique. Aside from the mere molds, dies, and tool fabrication, AM-EDM is materializing to finishing of automobiles and aerospace, nuclear, and biomedical components, through the concept of material migrations. The mechanism of material transfer by AM-EDM resembles electrophoretic deposition, whereby the additives in the AM-EDM dielectric fluids are melted and migrate to the machined surface, forming a mirror-like finishing characterized by extremely hard, nanostructured, and nanoporous layers. These layers promote the bone in-growth and strengthen the cell adhesion. Implant shaping and surface treatment through AM-EDM are becoming a key research focus in recent years. This paper reports and summarizes the current advancement of AM-EDM as a potential tool for orthopedic and dental implant fabrication. Towards the end of this paper, the current challenges and future research trends are highlighted.

  6. Electric vehicles pick up speed as oil prices climb. [General Motors planning EVs in 1985

    Energy Technology Data Exchange (ETDEWEB)

    Bowe, J.

    1980-02-01

    General Motors recently announced that in 1985, its Chevrolet division will begin manufacturing either two-passenger electric automobiles, or small electric vans, or both. Key features of the electric-vehicles will be a separately excited DC motor, regenerative braking, electronic controls, and coil-type suspension. Newly developed zinc-nickel batteries promise higher speeds (up to about 55 mph) and a longer cruising range (about 100 mi before needing a recharge and 30,000 mi before needing replacement). General Motors' commitment to the electric-vehicle market signals the beginning of a radical departure from a traditional petroleum-based economy. (1 diagram, 1 drawing, 2 photos)

  7. The release of nickel and other trace elements from electric kettles and coffee machines

    DEFF Research Database (Denmark)

    Berg, T.; Petersen, Annette; Pedersen, Gitte Alsing

    2000-01-01

    was improved. Two of these ten kettles still released more than 50 mu g/l nickel to water under the test conditions. These two kettles, however, were subsequently withdrawn from the market. Coffee machines tested similarly did not release aluminium, lead, chromium or nickel in quantities of any significance....

  8. The release of nickel and other trace elements from electric kettles and coffee machines

    DEFF Research Database (Denmark)

    Berg, T.; Petersen, Annette; Pedersen, Gitte Alsing

    2000-01-01

    was improved. Two of these ten kettles still released more than 50 mu g/l nickel to water under the test conditions. These two kettles, however, were subsequently withdrawn from the market. Coffee machines tested similarly did not release aluminium, lead, chromium or nickel in quantities of any significance....

  9. Using the Zero-Resistance Spark Circuit on the Wire Cut Electric Discharge Machine to Realize Energy Savings

    Directory of Open Access Journals (Sweden)

    Shao-Hsien Chen

    2014-08-01

    Full Text Available There is an increasing emphasis on the development green manufacturing technologies. To improve processing and energy efficiency of modern Wire Cut Electric Discharge Machines (WEDM, many studies have focused on the design of the device’s discharge circuit. Currently, most such circuits use a resistor to impose current-limitations. When current flows through this resistor, considerable electrical energy converted into heat. The generated heat increases the temperature in the discharge circuit, which negatively impacts processing and energy efficiency, even though the temperature rise could be controlled by arranging cooling devices around the discharge circuit. This study seeks to produce an improved discharge circuit for use in WEDMs. We use DC-DC and electronic voltage regulation technology to convert the energy originally dissipated in the resistor directly into the energy for use in machining. The Zero-Resistance Spark Circuit is the critical design to realize the energy saving effect. Experimental results indicate energy savings of 10 to 15%.

  10. Modeling and design of cooperative braking in electric and hybrid vehicles using induction machine and hydraulic brake

    Directory of Open Access Journals (Sweden)

    Zaini Dalimus

    2016-07-01

    Full Text Available In mixed-mode braking applications, the electric motor / generator (M/G and hydraulic pressure valve are controlled to meet the driver’s braking demand. Controlling these braking elements is achieved by modulating the current generated by the M/G and adjusting the fluid pressure to the wheel brake cylinders. This paper aims to model and design combined regenerative and hydraulic braking systems which, comprise an induction electric machine, inverter, NiMH battery, controller, a pressure source, pressure control unit, and brake calipers. A 15 kW 1500 rpm induction machine equipped with a reduction gear having a gear ratio of 4 is used. A hydraulic brake capable to produce fluid pressure up to 40 bar is used. Direct torque control and pressure control are chosen as the control criteria in the M/G and the hydraulic solenoid valve. The braking demands for the system are derived from the Federal Testing Procedure (FTP drive cycle. Two simulation models have been developed in Matlab®/Simulink® to analyze the performance of the control strategy in each braking system. The developed model is validated through experiment. It is concluded that the control system does introduce torque ripple and pressure oscillation in the braking system, but these effects do not affect vehicle braking performance due to the high frequency nature of pressure fluctuation and the damping effect of the vehicle inertia. Moreover, experiment results prove the effectiveness of the developed model.

  11. A Two-Phase Spherical Electric Machine for Generating Rotating Uniform Magnetic Fields

    Science.gov (United States)

    2007-06-01

    the skin depth of copper, with /1 = /10 = 471" X 10-7 Henries/meter and (J = 5.8 X 107 Siemens /meter, for frequencies between one and 1000 Hz. The...pods that contain 21.5 MW Alstom electric motors [.51]. 7.3. FUTURE MACHINERY EXPERIMENTS 93 the flux leakage from large electric motors and to test

  12. General Electric ATS program technical review: Phase 2 activities

    Energy Technology Data Exchange (ETDEWEB)

    Chance, T. [GE Power Generation, Schenectady, NY (United States); Smith, D. [GE Corporate Research & Development Center, Schenectady, NY (United States)

    1995-10-01

    In response to the industrial and utility objectives specified for the ATS, the GE Power Generation ATS Phase 2 Program consisted of a dual approach. These were (1) development of an Industrial ATS (aircraft engine based) led by GE Aircraft Engines, and (2) development of a Utility ATS which was already underway at GEPG. Both programs required the identification and resolution of critical technical issues. Both systems were studied in Tasks 3-7, and both have resulted in designs that meet all ATS goals. The Industrial ATS as defined (130 MW) did not meet projected market power size requirements, and emphasis has remained on the Utility ATS development. The design and testing effort has been focused on the MS7001H combined cycle gas turbine, as the next product evolution in GE Power Generation`s product line. Common technology derived from the ATS Program is also being incorporated into the 50 Hz version of the ATS utility machine designated as the MS9001H.

  13. Process Design of Shaft Machining with General Machine Tool%普通机床加工轴的工艺设计

    Institute of Scientific and Technical Information of China (English)

    王德鹏

    2015-01-01

    通常用轴传递动力和扭矩或者支撑位于轴上的传动零部件,并使之保持相对位置。根据轴的受力特点不同,一般采用阶梯轴结构,才能满足要求。在普通机床轴的加工,效率较低,精度不容易达到要求。本文通过某阶梯轴的零件分析及工艺分析,设计出了较合理的机械加工工艺,在保证加工质量的前提上,对提高生产效率,合理使用机床等进行了有益探讨。%Usually the shaft is used to transmit power and torque or support the transmission parts on the shaft and keep their position. According to the different loading features of the shaft, usually stepped shaft is adopted to meet the requirements. The processing of shaft with general machine tool is low in efficiency and can't meet the desired accuracy. Through part analysis and process analysis of a kind of stepped shaft, a reasonable machining process technology is designed, which is beneficial for improving production efficiency and reasonable use of the machine tool o the basis of ensuring the processing quality.

  14. Power distribution of a co-axial dual-mechanical-port flux-switching permanent magnet machine for fuel-based extended range electric vehicles

    Directory of Open Access Journals (Sweden)

    Lingkang Zhou

    2017-05-01

    Full Text Available In this paper, power distribution between the inner and outer machines of a co-axial dual-mechanical-port flux-switching permanent magnet (CADMP-FSPM machine is investigated for fuel-based extended range electric vehicle (ER-EV. Firstly, the topology and operation principle of the CADMP-FSPM machine are introduced, which consist of an inner FSPM machine used for high-speed, an outer FSPM machine for low-speed, and a magnetic isolation ring between them. Then, the magnetic field coupling of the inner and outer FSPM machines is analyzed with more attention paid to the optimization of the isolation ring thickness. Thirdly, the power-dimension (PD equations of the inner and outer FSPM machines are derived, respectively, and thereafter, the PD equation of the whole CADMP-FSPM machine can be given. Finally, the PD equations are validated by finite element analysis, which supplies the guidance on the design of this type of machines.

  15. Monocoil reciprocating permanent magnet electric machine with self-centering force

    Science.gov (United States)

    Bhate, Suresh K. (Inventor); Vitale, Nicholas G. (Inventor)

    1989-01-01

    A linear reciprocating machine has a tubular outer stator housing a coil, a plunger and an inner stator. The plunger has four axially spaced rings of radially magnetized permanent magnets which cooperate two at a time with the stator to complete first or second opposite magnetic paths. The four rings of magnets and the stators are arranged so that the stroke of the plunger is independent of the axial length of the coil.

  16. Prognostic and Fault Tolerant Reconfiguration Strategies for Aerospace Power Electronic Controllers and Electric Machines Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Impact Technologies proposes to develop a real-time prognostic and fault/failure accommodation system of critical electric power system components including power...

  17. A Generalized Model for Transport of Contaminants in Soil by Electric Fields

    DEFF Research Database (Denmark)

    Paz-Garcia, Juan Manuel; Baek, Kitae; Alshawabkeh, Iyad D.

    2012-01-01

    A generalized model applicable to soils contaminated with multiple species under enhanced boundary conditions during treatment by electric fields is presented. The partial differential equations describing species transport are developed by applying the law of mass conservation to their fluxes...

  18. Conformal invariance and generalized Hojman conserved quantities of mechanico-electrical systems

    Institute of Scientific and Technical Information of China (English)

    Li Yuan-Cheng; Xia Li-Li; Wang Xiao-Ming

    2009-01-01

    This paper studies conformal invariance and generalized Hojman conserved quantities of mechanico-electrical systems. The definition and the determining equation of conformal invariance for mechanico-electrical systems are provided. The conformal factor expression is deduced from conformal invariance and Lie symmetry under the infinitesimal singleparameter transformation group. The generalized Hojman conserved quantities from the conformal invariance of the system are given. An example is given to illustrate the application of the result.

  19. Control strategy minimizing the converter-alternating current motor losses: application to electric traction; Strategies de commande minimisant les pertes d'un ensemble convertisseur - machine alternative: application a la traction electrique

    Energy Technology Data Exchange (ETDEWEB)

    Bastiani, Ph.

    2001-02-01

    Improving the efficiency of the converter-alternating current motor system is a major task in electric traction. Global energy optimisation implies a specific approach at system scale. To reach this goal, we have chosen an algebraic method using sub-system models. To start with, a synchronous machine Park model is developed to take account magnetic saturation and iron losses. Then, an averaged model of the voltage inverter is used in order to obtain a simplified model of the losses to be implemented in our optimisation method. This is how the global model is built including losses in the synchronous machine along with the losses of the power converter. Experimental results are there to validate our approach. This study proposes a method based on algebraic formulation of the general laws to control torque. Algorithms take into account magnetic circuits saturation and power losses in both the machine and its converter. Here again, experimental results validate the algorithm on several test benches. Achieved efficiency improvement is important compared to existing usual control strategies. The proposed method can be generalised to other machine-converter systems. As a matter of fact we have extended our study to the induction machine. As a complement ti this study we have looked at the effects natural limitations of voltages and currents in the torque-speed plane. Therefore algebraic formulation of the torque-speed plane and optimisation strategies are proposed including those constraints. (author)

  20. General theories for the electrical transport properties of carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Singh, L T; Nanda, K K, E-mail: nanda@mrc.iisc.ernet.in [Materials Research Centre, Indian Institute of Science, Bangalore-560012 (India)

    2011-08-05

    We have shown that the general theories of metals and semiconductors can be employed to understand the diameter and voltage dependency of current through metallic and semiconducting carbon nanotubes, respectively. The current through a semiconducting multiwalled carbon nanotube (MWCNT) is associated with the energy gap that is different for different shells. The contribution of the outermost shell is larger as compared to the inner shells. The general theories can also explain the diameter dependency of maximum current through nanotubes. We have also compared the current carrying ability of a MWCNT and an array of the same diameter of single wall carbon nanotubes (SWCNTs) and found that MWCNTs are better suited and deserve further investigation for possible applications as interconnects.

  1. Modeling and Estimating of Load Demand of Electricity Generated from Hydroelectric Power Plants in Turkey using Machine Learning Methods

    Directory of Open Access Journals (Sweden)

    DURSUN, B.

    2014-02-01

    Full Text Available In this study, the electricity load demand, between 2012 and 2021, has been estimated using the load demand of the electricity generated from hydroelectric power plants in Turkey between 1970 and 2011. Among machine learning algorithms, Multilayer Perceptron, Locally Weighted Learning, Additive Regression, M5Rules and ZeroR classifiers are used to estimate the electricity load demand. Among them, M5Rules and Multilayer Perceptron classifiers are observed to have better performance than the others. ZeroR classifier is a kind of majority classifier used to compare the performances of other classifiers. Locally Weighted Learning and Additive Regression classifiers are Meta classifiers. In the training period conducted by Locally Weighted Learning and Additive Regression classifiers, when Multilayer Perceptron and M5Rules classifiers are chosen respectively, it is possible to obtain models with the highest performance. As a result of the experiments performed using M5Rules and Multilayer Perceptron classifiers, correlation coefficient values of 0.948 and 0.9933 are obtained respectively. And, Mean Absolute Error and Root Mean Squared Error value of Multilayer Perceptron classifier are closer to zero than that of M5Rules classifier. Therefore, it can be said the model performed by Multilayer Perceptron classifier has the best performance compared to the models of other classifiers.

  2. MACHINE TOOL OPERATOR--GENERAL, ENTRY, SUGGESTED GUIDE FOR A TRAINING COURSE.

    Science.gov (United States)

    RONEY, MAURICE W.; AND OTHERS

    THE PURPOSE OF THIS CURRICULUM GUIDE IS TO ASSIST THE ADMINISTRATOR AND INSTRUCTOR IN PLANNING AND DEVELOPING MANPOWER DEVELOPMENT AND TRAINING PROGRAMS TO PREPARE MACHINE TOOL OPERATORS FOR ENTRY-LEVEL POSITIONS. THE COURSE OUTLINE PROVIDES UNITS IN -- (1) ORIENTATION, (2) BENCH WORK, (3) SHOP MATHEMATICS, (4) BLUEPRINT READING AND SKETCHING, (5)…

  3. On electrical correlates of Physarum polycephalum spatial activity: Can we see Physarum Machine in the dark?

    CERN Document Server

    Adamatzky, Andrew

    2010-01-01

    Plasmodium of Physarum polycephalum is a single cell visible by unaided eye, which spans sources of nutrients with its protoplasmic network. In a very simple experimental setup we recorded electric potential of the propagating plasmodium. We discovered a complex interplay of short range oscillatory behaviour combined with long range, low frequency oscillations which serve to communicate information between different parts of the plasmodium. The plasmodium's response to changing environmental conditions forms basis patterns of electric activity, which are unique indicators of the following events: plasmodium occupies a site, plasmodium functions normally, plasmodium becomes `agitated' due to drying substrate, plasmodium departs a site, and plasmodium forms sclerotium. Using a collective particle approximation of Physarum polycephalum we found matching correlates of electrical potential in computational simulations by measuring local population flux at the node positions, generating trains of high and low frequ...

  4. Key Performance Parameter Driven Technology Goals for Electric Machines and Power Systems

    Science.gov (United States)

    Bowman, Cheryl; Jansen, Ralph; Brown, Gerald; Duffy, Kirsten; Trudell, Jeffrey

    2015-01-01

    Transitioning aviation to low carbon propulsion is one of the crucial strategic research thrust and is a driver in the search for alternative propulsion system for advanced aircraft configurations. This work requires multidisciplinary skills coming from multiple entities. The feasibility of scaling up various electric drive system technologies to meet the requirements of a large commercial transport is discussed in terms of key parameters. Functional requirements are identified that impact the power system design. A breakeven analysis is presented to find the minimum allowable electric drive specific power and efficiency that can preserve the range, initial weight, operating empty weight, and payload weight of the base aircraft.

  5. Generalized eMC implementation for Monte Carlo dose calculation of electron beams from different machine types.

    Science.gov (United States)

    Fix, Michael K; Cygler, Joanna; Frei, Daniel; Volken, Werner; Neuenschwander, Hans; Born, Ernst J; Manser, Peter

    2013-05-07

    The electron Monte Carlo (eMC) dose calculation algorithm available in the Eclipse treatment planning system (Varian Medical Systems) is based on the macro MC method and uses a beam model applicable to Varian linear accelerators. This leads to limitations in accuracy if eMC is applied to non-Varian machines. In this work eMC is generalized to also allow accurate dose calculations for electron beams from Elekta and Siemens accelerators. First, changes made in the previous study to use eMC for low electron beam energies of Varian accelerators are applied. Then, a generalized beam model is developed using a main electron source and a main photon source representing electrons and photons from the scattering foil, respectively, an edge source of electrons, a transmission source of photons and a line source of electrons and photons representing the particles from the scrapers or inserts and head scatter radiation. Regarding the macro MC dose calculation algorithm, the transport code of the secondary particles is improved. The macro MC dose calculations are validated with corresponding dose calculations using EGSnrc in homogeneous and inhomogeneous phantoms. The validation of the generalized eMC is carried out by comparing calculated and measured dose distributions in water for Varian, Elekta and Siemens machines for a variety of beam energies, applicator sizes and SSDs. The comparisons are performed in units of cGy per MU. Overall, a general agreement between calculated and measured dose distributions for all machine types and all combinations of parameters investigated is found to be within 2% or 2 mm. The results of the dose comparisons suggest that the generalized eMC is now suitable to calculate dose distributions for Varian, Elekta and Siemens linear accelerators with sufficient accuracy in the range of the investigated combinations of beam energies, applicator sizes and SSDs.

  6. Generalized eMC implementation for Monte Carlo dose calculation of electron beams from different machine types

    Science.gov (United States)

    Fix, Michael K.; Cygler, Joanna; Frei, Daniel; Volken, Werner; Neuenschwander, Hans; Born, Ernst J.; Manser, Peter

    2013-05-01

    The electron Monte Carlo (eMC) dose calculation algorithm available in the Eclipse treatment planning system (Varian Medical Systems) is based on the macro MC method and uses a beam model applicable to Varian linear accelerators. This leads to limitations in accuracy if eMC is applied to non-Varian machines. In this work eMC is generalized to also allow accurate dose calculations for electron beams from Elekta and Siemens accelerators. First, changes made in the previous study to use eMC for low electron beam energies of Varian accelerators are applied. Then, a generalized beam model is developed using a main electron source and a main photon source representing electrons and photons from the scattering foil, respectively, an edge source of electrons, a transmission source of photons and a line source of electrons and photons representing the particles from the scrapers or inserts and head scatter radiation. Regarding the macro MC dose calculation algorithm, the transport code of the secondary particles is improved. The macro MC dose calculations are validated with corresponding dose calculations using EGSnrc in homogeneous and inhomogeneous phantoms. The validation of the generalized eMC is carried out by comparing calculated and measured dose distributions in water for Varian, Elekta and Siemens machines for a variety of beam energies, applicator sizes and SSDs. The comparisons are performed in units of cGy per MU. Overall, a general agreement between calculated and measured dose distributions for all machine types and all combinations of parameters investigated is found to be within 2% or 2 mm. The results of the dose comparisons suggest that the generalized eMC is now suitable to calculate dose distributions for Varian, Elekta and Siemens linear accelerators with sufficient accuracy in the range of the investigated combinations of beam energies, applicator sizes and SSDs.

  7. Design of a Permanent Magnet Synchronous Machine for a Flywheel Energy Storage System within a Hybrid Electric Vehicle

    Science.gov (United States)

    Jiang, Ming

    As an energy storage device, the flywheel has significant advantages over conventional chemical batteries, including higher energy density, higher efficiency, longer life time, and less pollution to the environment. An effective flywheel system can be attributed to its good motor/generator (M/G) design. This thesis describes the research work on the design of a permanent magnet synchronous machine (PMSM) as an M/G suitable for integration in a flywheel energy storage system within a large hybrid electric vehicle (HEV). The operating requirements of the application include wide power and speed ranges combined with high total system efficiency. Along with presenting the design, essential issues related to PMSM design including cogging torque, iron losses and total harmonic distortion (THD) are investigated. An iterative approach combining lumped parameter analysis with 2D Finite Element Analysis (FEA) was used, and the final design is presented showing excellent performance.

  8. Characterization of electric discharge machining, subsequent etching and shot-peening as a surface treatment for orthopedic implants

    Science.gov (United States)

    Stráský, Josef; Havlíková, Jana; Bačáková, Lucie; Harcuba, Petr; Mhaede, Mansour; Janeček, Miloš

    2013-09-01

    Presented work aims at multi-method characterization of combined surface treatment of Ti-6Al-4V alloy for biomedical use. Surface treatment consists of consequent use of electric discharge machining (EDM), acid etching and shot peening. Surface layers are analyzed employing scanning electron microscopy and energy dispersive X-ray spectroscopy. Acid etching by strong Kroll's reagent is capable of removing surface layer of transformed material created by EDM. Acid etching also creates partly nanostructured surface and significantly contributes to the enhanced proliferation of the bone cells. The cell growth could be positively affected by the superimposed bone-inspired structure of the surface with the morphological features in macro-, micro- and nano-range. Shot peening significantly improves poor fatigue performance after EDM. Final fatigue performance is comparable to benchmark electropolished material without any adverse surface effect. The proposed three-step surface treatment is a low-cost process capable of producing material that is applicable in orthopedics.

  9. Electric Load Forecasting Based on a Least Squares Support Vector Machine with Fuzzy Time Series and Global Harmony Search Algorithm

    Directory of Open Access Journals (Sweden)

    Yan Hong Chen

    2016-01-01

    Full Text Available This paper proposes a new electric load forecasting model by hybridizing the fuzzy time series (FTS and global harmony search algorithm (GHSA with least squares support vector machines (LSSVM, namely GHSA-FTS-LSSVM model. Firstly, the fuzzy c-means clustering (FCS algorithm is used to calculate the clustering center of each cluster. Secondly, the LSSVM is applied to model the resultant series, which is optimized by GHSA. Finally, a real-world example is adopted to test the performance of the proposed model. In this investigation, the proposed model is verified using experimental datasets from the Guangdong Province Industrial Development Database, and results are compared against autoregressive integrated moving average (ARIMA model and other algorithms hybridized with LSSVM including genetic algorithm (GA, particle swarm optimization (PSO, harmony search, and so on. The forecasting results indicate that the proposed GHSA-FTS-LSSVM model effectively generates more accurate predictive results.

  10. Influence of Different Rotor Teeth Shapes on the Performance of Flux Switching Permanent Magnet Machines Used for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Jing Zhao

    2014-12-01

    Full Text Available This paper investigated a 12-slot/11-pole flux switching permanent magnet (FSPM machine used for electric vehicles (EVs. Five novel rotor teeth shapes are proposed and researched to reduce the cogging torque and torque ripple of the FSPM machine. These rotor teeth shapes are notched teeth, stepped teeth, eccentric teeth, combination of notched and stepped teeth, and combination of notched and eccentric teeth. They are applied on the rotor and optimized, respectively. The influences of different rotor teeth shapes on cogging torque, torque ripple and electromagnetic torque are analyzed by the 2-D finite-element method (FEM. Then, the performance of FSPMs with different rotor teeth shapes are compared and evaluated comprehensively from the points of view of cogging torque, torque ripple, electromagnetic torque, flux linkage, back electromotive force (EMF, and so on. The results show that the presented rotor teeth shapes, especially the combination of stepped and notched teeth, can greatly reduce the cogging torque and torque ripple with only slight changes in the average electromagnetic torque.

  11. Statistical investigations into the erosion of material from the tool in micro-electrical discharge machining

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2016-01-01

    This paper presents a statistical study of the erosion of material from the tool electrode in a micro-electrical dischargemachining process. The work involves Analysis of Variance and Analysis of Means approaches on the results of the toolelectrode wear rate obtained based on design of experiment...

  12. Understanding Power Electronics and Electrical Machines in Multidisciplinary Wind Energy Conversion System Courses

    Science.gov (United States)

    Duran, M. J.; Barrero, F.; Pozo-Ruz, A.; Guzman, F.; Fernandez, J.; Guzman, H.

    2013-01-01

    Wind energy conversion systems (WECS) nowadays offer an extremely wide range of topologies, including various different types of electrical generators and power converters. Wind energy is also an application of great interest to students and with a huge potential for engineering employment. Making WECS the main center of interest when teaching…

  13. Understanding Power Electronics and Electrical Machines in Multidisciplinary Wind Energy Conversion System Courses

    Science.gov (United States)

    Duran, M. J.; Barrero, F.; Pozo-Ruz, A.; Guzman, F.; Fernandez, J.; Guzman, H.

    2013-01-01

    Wind energy conversion systems (WECS) nowadays offer an extremely wide range of topologies, including various different types of electrical generators and power converters. Wind energy is also an application of great interest to students and with a huge potential for engineering employment. Making WECS the main center of interest when teaching…

  14. 机器视觉电动缝纫机关键技术研究%A Study on Key Technologies of Electric Sewing Machine Based on Machine Vision

    Institute of Scientific and Technical Information of China (English)

    崔群; 白顺科

    2014-01-01

    This article introduces the machine vision electric sewing machine,which is an intelligent electric sewing machine based on machine vision and numerical control tool. This machine can recognize and localize all of the sewing pieces of cloth on working table through the image sensors,can grab the sewing pieces of cloth by folding arm manipulator and can complete the accurate and reliable feeding work. So,the form clamp would be removed,and the manual work could be reduced.%研究了一种基于机器视觉和数控技术的工业智能缝纫设备的关键技术。该设备通过图像传感器对工作台上摆放的缝片进行识别与定位,通过送料机械手实现缝片的抓取并实现精确、快速、可靠地缝片的送料,以抛弃目前电动缝纫机的模板夹具,并实现减少操作工干预。

  15. Application of generalized Hough transform for detecting sugar beet plant from weed using machine vision method

    Directory of Open Access Journals (Sweden)

    A Bakhshipour Ziaratgahi

    2017-05-01

    Full Text Available Introduction Sugar beet (Beta vulgaris L. as the second most important world’s sugar source after sugarcane is one of the major industrial crops. The presence of weeds in sugar beet fields, especially at early growth stages, results in a substantial decrease in the crop yield. It is very important to efficiently eliminate weeds at early growing stages. The first step of precision weed control is accurate detection of weeds location in the field. This operation can be performed by machine vision techniques. Hough transform is one of the shape feature extraction methods for object tracking in image processing which is basically used to identify lines or other geometrical shapes in an image. Generalized Hough transform (GHT is a modified version of the Hough transform used not only for geometrical forms, but also for detecting any arbitrary shape. This method is based on a pattern matching principle that uses a set of vectors of feature points (usually object edge points to a reference point to construct a pattern. By comparing this pattern with a set pattern, the desired shape is detected. The aim of this study was to identify the sugar beet plant from some common weeds in a field using the GHT. Materials and Methods Images required for this study were taken at the four-leaf stage of sugar beet as the beginning of the critical period of weed control. A shelter was used to avoid direct sunlight and prevent leaf shadows on each other. The obtained images were then introduced to the Image Processing Toolbox of MATLAB programming software for further processing. Green and Red color components were extracted from primary RGB images. In the first step, binary images were obtained by applying the optimal threshold on the G-R images. A comprehensive study of several sugar beet images revealed that there is a unique feature in sugar beet leaves which makes them differentiable from the weeds. The feature observed in all sugar beet plants at the four

  16. Non Invasive Sensors for Monitoring the Efficiency of AC Electrical Rotating Machines

    Directory of Open Access Journals (Sweden)

    Thierry Jacq

    2010-08-01

    Full Text Available This paper presents a non invasive method for estimating the energy efficiency of induction motors used in industrial applications. This method is innovative because it is only based on the measurement of the external field emitted by the motor. The paper describes the sensors used, how they should be placed around the machine in order to decouple the external field components generated by both the air gap flux and the winding end-windings. The study emphasizes the influence of the eddy currents flowing in the yoke frame on the sensor position. A method to estimate the torque from the external field use is proposed. The measurements are transmitted by a wireless module (Zig-Bee and they are centralized and stored on a PC computer.

  17. Electric Drives with Permanent Magnet Synchronous Machines Connected to Internal Combustion Engines

    OpenAIRE

    Morandin, Mattia

    2013-01-01

    In recent years, the increasing cost of oil and Earth global warming due to greenhouse gases have pushed the scientific research, the governments and thus the markets in the direction of a higher efficiency of the systems in order to reduce the use of this fuel and therefore its associated emissions of CO2. Nowadays, the most involved sectors of this technological revolution are the fields of electricity generation and the transportation. In fact, these two sectors are the main accountable...

  18. CUTTING REGULARITY AND DISCHARGE CHARACTERISTICS BY USING COMPOSITE COOLING LIQUID IN WIRE CUT ELECTRICAL DISCHARGE MACHINE WITH HIGH WIRE TRAVELING SPEED

    Institute of Scientific and Technical Information of China (English)

    LIU Zhidong

    2008-01-01

    The analysis of cutting regularity is provided through using and comparing two typical cooling liquids. It is proved that cutting regularity is greatly affected by cooling liquid's washing ability. Discharge characteristics and theoretic analysis between two electrodes are also discussed based on discharge waveform. By using composite cooling liquid which has strong washing ability, the efficiency in the first stable cutting phase has reached more than 200 mm2/min, and the roughness of the surface has reached Ra<0.8 μm after the fourth cutting with more than 50 mm2/min average cutting efficiency. It is pointed out that cutting situation of the wire cut electrical discharge machine with high wire traveling speed (HSWEDM) is better than the wire cut electrical discharge machine with low wire traveling speed (LSWEDM) in the condition of improving the cooling liquid washing ability. The machining indices of HSWEDM will be increased remarkably by using the composite cooling liquid.

  19. 6061铝合金的电火花加工%Electrical discharge machining of 6061 aluminium alloy

    Institute of Scientific and Technical Information of China (English)

    A. PRAMANIK; A. K. BASAK; M. N. ISLAM; G. LITTLEFAIR

    2015-01-01

    在不同脉冲时间和导线张力下,研究6061铝合金电火花线切割加工过程中材料的去除率、切口/狭缝宽度、表面光洁度和线电极磨损,通过改变脉冲时间和导线张力,在电火花线切割加工机床上进行了8次实验.结果表明,随着脉冲时间的延长,材料的去除率增加,但导线张力不影响材料的去除率.较高的导线张力有利于促进加工工艺的稳定性,产生较低的线电极磨损和更好的表面光洁度.随着脉冲时间的变化,表面粗糙度没有明显变化.在所有加工条件下,表面外观非常相似.加工后表面包含凝固熔融材料、飞溅材料和气泡.由于热量输入的增加,脉冲时间的延长增大了线电极的磨损.线电极的磨损产生了斜槽,该斜槽正面的切口宽度比底部的宽.较高的电极损耗会产生较高的锥度.%The wire electrical discharge machining (EDM) of 6061 aluminium alloy in terms of material removal rate, kerf/slit width, surface finish and wear of electrode wire for different pulse on time and wire tension was studied. Eight experiments were carried out in a wire EDM machine by varying pulse on time and wire tension. It is found that the material removal rate increases with the increase of pulse on time though the wire tension does not affect the material removal rate. It seems that the higher wire tension facilitates steady machining process, which generates low wear in wire electrode and better surface finish. The surface roughness does not change notably with the variation of pulse on time. The appearance of the machined surfaces is very similar under all the machining conditions. The machined surface contains solidified molten material, splash of materials and blisters. The increase of the pulse on time increases the wear of wire electrode due to the increase of heat input. The wear of wire electrode generates tapered slot which has higher kerf width at top side than that at bottom side. The higher

  20. Electricity price forecasting using generalized regression neural network based on principal components analysis

    Institute of Scientific and Technical Information of China (English)

    牛东晓; 刘达; 邢棉

    2008-01-01

    A combined model based on principal components analysis (PCA) and generalized regression neural network (GRNN) was adopted to forecast electricity price in day-ahead electricity market. PCA was applied to mine the main influence on day-ahead price, avoiding the strong correlation between the input factors that might influence electricity price, such as the load of the forecasting hour, other history loads and prices, weather and temperature; then GRNN was employed to forecast electricity price according to the main information extracted by PCA. To prove the efficiency of the combined model, a case from PJM (Pennsylvania-New Jersey-Maryland) day-ahead electricity market was evaluated. Compared to back-propagation (BP) neural network and standard GRNN, the combined method reduces the mean absolute percentage error about 3%.

  1. Numerical Investigation of Entropy Generation in Unsteady MHD Generalized Couette Flow with Variable Electrical Conductivity

    Science.gov (United States)

    Chinyoka, T.; Makinde, O. D.

    2013-01-01

    The thermodynamic second law analysis is utilized to investigate the inherent irreversibility in an unsteady hydromagnetic generalized Couette flow with variable electrical conductivity in the presence of induced electric field. Based on some simplified assumption, the model nonlinear governing equations are obtained and solved numerically using semidiscretization finite difference techniques. Effects of various thermophysical parameters on the fluid velocity, temperature, current density, skin friction, the Nusselt number, entropy generation number, and the Bejan number are presented graphically and discussed quantitatively. PMID:23956691

  2. 浅谈机床电气的故障分析与检修%A Brief Discussion on Failure Analysis and Maintenance of Machine Tool Electric

    Institute of Scientific and Technical Information of China (English)

    刘予鲁

    2013-01-01

    In order to ensure the normal operation of machine tool equipment, the electrical maintenance staff should understand electric schematic diagram, enable to analyze common failures of electrical controlling circuits, and grasp circuit maintenance methods.%为确保机床设备能正常运行,电气维修人员必须读懂电路原理图,会分析常见的电气控制线路故障现象,掌握电路检修方法。

  3. Statistical investigations into the erosion of material from the tool in micro-electrical discharge machining

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2016-01-01

    This paper presents a statistical study of the erosion of material from the tool electrode in a micro-electrical dischargemachining process. The work involves Analysis of Variance and Analysis of Means approaches on the results of the toolelectrode wear rate obtained based on design of experiment...... gives the minimum material eerosion from the tool. It is observed that none of the two-factor interactions are significant in controlling the erosion ofmaterial from the Tool.......This paper presents a statistical study of the erosion of material from the tool electrode in a micro-electrical dischargemachining process. The work involves Analysis of Variance and Analysis of Means approaches on the results of the toolelectrode wear rate obtained based on design of experiments...... approach. The input factors used in the experiments aredischarge current (I ), discharge frequency (f ) and pulse width (w ). The individual effects as well as interactions pamong the input factors have been considered for the analysis. The results of this investigation show that dischargecurrent (I...

  4. Techniques Exploring on Machining External Thread of Hard Alloy by Electric Discharge Machine%硬质合金外螺纹的电火花成型机加工工艺探讨

    Institute of Scientific and Technical Information of China (English)

    何兴会; 杨国英

    2012-01-01

    结合硬质合金的材料特性,将电火花成型电极加工内外螺纹的工艺差异进行对比,分析硬质合金外螺纹电火花加工工艺难点,并提出合理的改进措施.再以电火花成型电极加工YG6硬质合金外螺纹为实例,运用改进方法成功加工出较高质量的外螺纹.结果表明:选取合适的峰值电流,改进加工电极结构是保证外螺纹加工质量的关键技术.最后对单电极电火花加工外螺纹的可行性工艺方案进行详细说明.%Considering the material attribute of hard alloy, the technique difference between external thread and inner thread machined by electric discharge machine is compared, and then the difficulties in machining external thread of hard alloy by electric discharge machine is analyzed and a better solution can be proposed. Take a machined work piece of YG6 for example to illustrate the high quality validity of the solutions. The results show that better quality is obtained by selecting suitable peak current and redesigning the electrode in machining external thread.

  5. Studying and Modeling the Effect of Graphite Powder Mixing Electrical Discharge Machining on the Main Process Characteristics

    Directory of Open Access Journals (Sweden)

    Ahmed N. Al-Khazraji

    2015-09-01

    Full Text Available This paper concerned with study the effect of a graphite micro powder mixed in the kerosene dielectric fluid during powder mixing electric discharge machining (PMEDM of high carbon high chromium AISI D2 steel. The type of electrode (copper and graphite, the pulse current and the pulse-on time and mixing powder in kerosene dielectric fluid are taken as the process main input parameters. The material removal rate MRR, the tool wear ratio TWR and the work piece surface roughness (SR are taken as output parameters to measure the process performance. The experiments are planned using response surface methodology (RSM design procedure. Empirical models are developed for MRR, TWR and SR, using the analysis of variance (ANOVA.The best results for the productivity of the process (MRR obtained when using the graphite electrodes, the pulse current (22 A, the pulse on duration (120 µs and using the graphite powder mixing in kerosene dielectric reaches (82.84mm³/min. The result gives an improvement in material removal rate of (274% with respect to the corresponding value obtained when copper electrodes with kerosene dielectric alone. The best results for the tool wear ratio (TWR of the process obtained when using the copper electrodes, the pulse current (8 A, the pulse on duration (120 µs and using the kerosene dielectric alone reaches (0.31 %. The use of graphite electrodes, the kerosene dielectric with 5g/l graphite powder mixing, the pulse current (8 A, the pulse on duration (40 µs give the best surface roughness of a value (2.77 µm.This result yields an improvement in SR by (141% with respect to the corresponding value obtained when using copper electrodes and the kerosene dielectric alone with the same other parameters and machining conditions.

  6. Automatic Multi-GPU Code Generation applied to Simulation of Electrical Machines

    CERN Document Server

    Rodrigues, Antonio Wendell De Oliveira; Dekeyser, Jean-Luc; Menach, Yvonnick Le

    2011-01-01

    The electrical and electronic engineering has used parallel programming to solve its large scale complex problems for performance reasons. However, as parallel programming requires a non-trivial distribution of tasks and data, developers find it hard to implement their applications effectively. Thus, in order to reduce design complexity, we propose an approach to generate code for hybrid architectures (e.g. CPU + GPU) using OpenCL, an open standard for parallel programming of heterogeneous systems. This approach is based on Model Driven Engineering (MDE) and the MARTE profile, standard proposed by Object Management Group (OMG). The aim is to provide resources to non-specialists in parallel programming to implement their applications. Moreover, thanks to model reuse capacity, we can add/change functionalities or the target architecture. Consequently, this approach helps industries to achieve their time-to-market constraints and confirms by experimental tests, performance improvements using multi-GPU environmen...

  7. Statistical investigations into the erosion of material from the tool in micro-electrical discharge machining

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2016-01-01

    This paper presents a statistical study of the erosion of material from the tool electrode in a micro-electrical dischargemachining process. The work involves Analysis of Variance and Analysis of Means approaches on the results of the toolelectrode wear rate obtained based on design of experiments...... ) and discharge frequency (f ) control the erosion of material from the tool electrode. The Material Erosion dfrom the tool electrode increases linearly with the discharge frequency. As the current index increases from 20 to 35,the M decreases linearly, by 29% and then increases by of 36%. The current index of 35...... gives the minimum material eerosion from the tool. It is observed that none of the two-factor interactions are significant in controlling the erosion ofmaterial from the Tool....

  8. General Electric Company proposed management plan, commercial buildings, National Solar Demonstration Program

    Energy Technology Data Exchange (ETDEWEB)

    None

    1976-04-01

    The National Solar Demonstration Plan (NSDP) for the solar heating and cooling of non-residential buildings is designed to meet the goals and objectives of ERDA 23A. The plan has been formulated for a matrix of two hundred (200) commercial demonstration projects. This report contains the General Electric recommendations for the NSDP pertaining to the management structure, demonstration implementation, schedules, data dissemination, and resource requirements. Closely associated with these major planning elements are the related elements in the other recent General Electric reports submitted under the SHACOB Phase I contract. (WDM)

  9. Generalized Mei Conserved Quantity of Mei Symmetry for Mechanico-electrical Systems with Nonholonomic Controllable Constraints

    Institute of Scientific and Technical Information of China (English)

    XIA Li-Li; ZHAO Xian-Lin

    2009-01-01

    On the basis of the total time derivative along the trajectory, we study the generalized Mei conserved quantity of Mei symmetry for mechanico-electrical systems with nonholonomie controllable constraints. Firstly, the definition and criterion of Mei symmetry for mechanico-electrical systems with nonholonomic controllable constraints are presented. Secondly, a coordination function is introduced, and the conditions of existence of generalized Mei conserved quantity as well as the forms are proposed. Lastly, an example is given to illustrate the application of the results.

  10. Results from the Operational Testing of the General Electric Smart Grid Capable Electric Vehicle Supply Equipment (EVSE)

    Energy Technology Data Exchange (ETDEWEB)

    Richard Barney Carlson; Don Scoffield; Brion Bennett

    2013-12-01

    The Idaho National Laboratory conducted testing and analysis of the General Electric (GE) smart grid capable electric vehicle supply equipment (EVSE), which was a deliverable from GE for the U.S. Department of Energy FOA-554. The Idaho National Laboratory has extensive knowledge and experience in testing advanced conductive and wireless charging systems though INL’s support of the U.S. Department of Energy’s Advanced Vehicle Testing Activity. This document details the findings from the EVSE operational testing conducted at the Idaho National Laboratory on the GE smart grid capable EVSE. The testing conducted on the EVSE included energy efficiency testing, SAE J1772 functionality testing, abnormal conditions testing, and charging of a plug-in vehicle.

  11. A preconditioned Jacobi-Davidson method for solving large generalized memory machines

    NARCIS (Netherlands)

    Booten, J.G.L.; Vorst, H.A. van der; Meijer, P.M.; Riele, H.J.J. te

    1994-01-01

    In this paper we apply the recently proposed Jacobi-Davidson method for calculating extreme eigenvalues of large matrices to a generalized eigenproblem. This leads to an algorithm that computes the extreme eigensolutions of a matrix pencil (A;B), where A and B are general matrices. Factorization of

  12. A preconditioned Jacobi-Davidson method for solving large generalized memory machines

    NARCIS (Netherlands)

    Booten, J.G.L.; Vorst, H.A. van der; Meijer, P.M.; Riele, H.J.J. te

    2001-01-01

    In this paper we apply the recently proposed Jacobi-Davidson method for calculating extreme eigenvalues of large matrices to a generalized eigenproblem. This leads to an algorithm that computes the extreme eigensolutions of a matrix pencil (A;B), where A and B are general matrices. Factorization of

  13. Generalizing Single Variable Functions to Two-Variable Functions, Function Machine and APOS

    Science.gov (United States)

    Kabael, Tangul Uygur

    2011-01-01

    The focus of this study in which the theoretical framework of APOS was used is students' generalizing function notion from single variable to two-variable function concepts in Analysis II course in the elementary mathematics education program. In the teaching process, teaching activities that support generalizing the function notion with multiple…

  14. Magnetohydrodynamic flow of generalized Maxwell fluids in a rectangular micropump under an AC electric field

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Guangpu [School of Mathematical Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021 (China); Jian, Yongjun, E-mail: jianyj@imu.edu.cn [School of Mathematical Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021 (China); Chang, Long [School of Mathematics and Statistics, Inner Mongolia University of Finance and Economics, Hohhot, Inner Mongolia 010051 (China); Buren, Mandula [School of Mathematical Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021 (China)

    2015-08-01

    By using the method of separation of variables, an analytical solution for the magnetohydrodynamic (MHD) flow of the generalized Maxwell fluids under AC electric field through a two-dimensional rectangular micropump is reduced. By the numerical computation, the variations of velocity profiles with the electrical oscillating Reynolds number Re, the Hartmann number Ha, the dimensionless relaxation time De are studied graphically. Further, the comparison with available experimental data and relevant researches is presented. - Highlights: • MHD flow of the generalized Maxwell fluids under AC electric field is analyzed. • The MHD flow is confined to a two-dimensional rectangular micropump. • Analytical solution is obtained by using the method of separation of variables. • The influences of related parameters on the MHD velocity are discussed.

  15. 76 FR 68634 - Airworthiness Directives; General Electric Company (GE) CF6 Turbofan Engines

    Science.gov (United States)

    2011-11-07

    ... visual inspections of the forward engine mount assembly side links for cracks, stripping and reapplying... 9346M99P04, installed on the forward engine mount assembly (also known as Configuration 2). Unsafe Condition...-04] RIN 2120-AA64 Airworthiness Directives; General Electric Company (GE) CF6 Turbofan Engines...

  16. 75 FR 77570 - Airworthiness Directives; General Electric Company CF6 Series Turbofan Engines

    Science.gov (United States)

    2010-12-13

    ... engine mount assembly (also known ] as Configuration 2). These engines are installed on, but not limited... Company CF6 Series Turbofan Engines AGENCY: Federal Aviation Administration (FAA), DOT. ACTION: Notice of...) for General Electric (GE) CF6-45/-50 series and CF6-80A series turbofan engines with certain...

  17. Characterization of electric discharge machining, subsequent etching and shot-peening as a surface treatment for orthopedic implants

    Energy Technology Data Exchange (ETDEWEB)

    Stráský, Josef, E-mail: josef.strasky@gmail.com [Charles University, Department of Physics of Materials (Czech Republic); Havlíková, Jana; Bačáková, Lucie [Institute of Physiology, Academy of Sciences of the Czech Republic (Czech Republic); Harcuba, Petr [Charles University, Department of Physics of Materials (Czech Republic); Mhaede, Mansour [Clausthal University of Technology, Institute of Materials Science and Engineering (Germany); Faculty of Engineering, Zagazig University (Egypt); Janeček, Miloš [Charles University, Department of Physics of Materials (Czech Republic)

    2013-09-15

    Presented work aims at multi-method characterization of combined surface treatment of Ti–6Al–4V alloy for biomedical use. Surface treatment consists of consequent use of electric discharge machining (EDM), acid etching and shot peening. Surface layers are analyzed employing scanning electron microscopy and energy dispersive X-ray spectroscopy. Acid etching by strong Kroll's reagent is capable of removing surface layer of transformed material created by EDM. Acid etching also creates partly nanostructured surface and significantly contributes to the enhanced proliferation of the bone cells. The cell growth could be positively affected by the superimposed bone-inspired structure of the surface with the morphological features in macro-, micro- and nano-range. Shot peening significantly improves poor fatigue performance after EDM. Final fatigue performance is comparable to benchmark electropolished material without any adverse surface effect. The proposed three-step surface treatment is a low-cost process capable of producing material that is applicable in orthopedics.

  18. Surface treatment by electric discharge machining of Ti-6Al-4V alloy for potential application in orthopaedics.

    Science.gov (United States)

    Harcuba, Petr; Bačáková, Lucie; Stráský, Josef; Bačáková, Markéta; Novotná, Katarína; Janeček, Miloš

    2012-03-01

    This study investigated the properties of Ti-6Al-4V alloy after surface treatment by the electric discharge machining (EDM) process. The EDM process with high peak currents proved to induce surface macro-roughness and to cause chemical changes to the surface. Evaluations were made of the mechanical properties by means of tensile tests, and of surface roughness for different peak currents of the EDM process. The EDM process with peak current of 29 A was found to induce sufficient surface roughness, and to have a low adverse effect on tensile properties. The chemical changes were studied by scanning electron microscopy equipped with an energy dispersive X-ray analyser (EDX). The surface of the benchmark samples was obtained by plasma-spraying a titanium dioxide coating. An investigation of the biocompatibility of the surface-treated Ti-6Al-4V samples in cultures of human osteoblast-like MG 63 cells revealed that the samples modified by EDM provided better substrates for the adhesion, growth and viability of MG 63 cells than the TiO2 coated surface. Thus, EDM treatment can be considered as a promising surface modification to orthopaedic implants, in which good integration with the surrounding bone tissue is required.

  19. Prediction of material removal rate and surface roughness for wire electrical discharge machining of nickel using response surface methodology

    Directory of Open Access Journals (Sweden)

    Thangam Chinnadurai

    2016-12-01

    Full Text Available This study focuses on investigating the effects of process parameters, namely, Peak current (Ip, Pulse on time (Ton, Pulse off time (Toff, Water pressure (Wp, Wire feed rate (Wf, Wire tension (Wt, Servo voltage (Sv and Servo feed setting (Sfs, on the Material Removal Rate (MRR and Surface Roughness (SR for Wire electrical discharge machining (Wire-EDM of nickel using Taguchi method. Response Surface Methodology (RSM is adopted to evolve mathematical relationships between the wire cutting process parameters and the output variables of the weld joint to determine the welding input parameters that lead to the desired optimal wire cutting quality. Besides, using response surface plots, the interaction effects of process parameters on the responses are analyzed and discussed. The statistical software Mini-tab is used to establish the design and to obtain the regression equations. The developed mathematical models are tested by analysis-of-variance (ANOVA method to check their appropriateness and suitability. Finally, a comparison is made between measured and calculated results, which are in good agreement. This indicates that the developed models can predict the responses accurately and precisely within the limits of cutting parameter being used.

  20. Fuzzy decentralized control for three-machine electric power model system; Sanki model keito no fuzzy bunsan seigyo

    Energy Technology Data Exchange (ETDEWEB)

    Kawamoto, S.; Takino, K. [Osaka Prefectural University, Osaka (Japan); Nojiri, K. [Kansai Electric Power Co. Inc., Osaka (Japan)

    1996-11-20

    In order to maintain the high reliability and security of electric power systems, the problem for stabilizing control is thought to be one of important subjects. Also, for the control of complex large scale nonlinear system like power system, decentralized control is preferable to centralized one. Therefore, the field of decentralized technology is much expected for the future power system. In this paper, a three-machine power model system is treated as an example, and first a decentralized system is constructed on a basis of the swing data by looking over the whole system at the largest generator bus. Next, the decentralized system is rewritten into a form of fuzzy system, and the stability theorem is applied to it. Then, feedback gains of the fuzzy control input can be determined under the guarantee of the stability, and the control input is given to the generator. Similarly, for the second generator, the decentralized system is obtained, and so on. Finally, it is shown that the decentralized control is constructed by using swing data based on three different faults, and is also available for another fault in the simulation. 10 refs., 10 figs., 1 tab.

  1. Grupos electrógenos y calidad de la energía; Reciprocating Machines and Power Quality

    Directory of Open Access Journals (Sweden)

    Marielys Francisco Fernández

    2011-02-01

    Full Text Available Entre las tecnologías de mayor difusión que hoy día se utilizan dentro de la generación distribuida (GDestán los grupos electrógenos (GE. La presencia de los GE en cualquiera de sus formas de explotación,exige un análisis de los problemas que puedan presentarse por su presencia; uno de estos problemas estárelacionado con la calidad de la energía eléctrica (CEL. El presente trabajo expone los primeros resultadosde un estudio que va dirigido a buscar respuestas sobre este tema ante diferentes tipos de perturbacionesque pueden presentarse en la red: Cortocircuito y variación de la tensión en los terminales del GE y ladesconexión súbita de la carga (rechazo de carga. Reciprocating machine (RM is one of the technology more used on distributed generation (DG. Thepresence of RM not manner its operation form need an analysis about differents problems: One of them isrelated with power quality (PQ. First results obained inside one study directed to obtain answers aboutdifferents perturbations for the RM presence like shortcircuit and voltage variation on RM termianls andrejected charge is presented in this paper. 

  2. The BSM-AI project: SUSY-AI-generalizing LHC limits on supersymmetry with machine learning

    Energy Technology Data Exchange (ETDEWEB)

    Caron, Sascha [Radboud Universiteit, Institute for Mathematics, Astro- and Particle Physics IMAPP, Nijmegen (Netherlands); Nikhef, Amsterdam (Netherlands); Kim, Jong Soo [UAM/CSIC, Instituto de Fisica Teorica, Madrid (Spain); Rolbiecki, Krzysztof [UAM/CSIC, Instituto de Fisica Teorica, Madrid (Spain); University of Warsaw, Faculty of Physics, Warsaw (Poland); Ruiz de Austri, Roberto [IFIC-UV/CSIC, Instituto de Fisica Corpuscular, Valencia (Spain); Stienen, Bob [Radboud Universiteit, Institute for Mathematics, Astro- and Particle Physics IMAPP, Nijmegen (Netherlands)

    2017-04-15

    A key research question at the Large Hadron Collider is the test of models of new physics. Testing if a particular parameter set of such a model is excluded by LHC data is a challenge: it requires time consuming generation of scattering events, simulation of the detector response, event reconstruction, cross section calculations and analysis code to test against several hundred signal regions defined by the ATLAS and CMS experiments. In the BSM-AI project we approach this challenge with a new idea. A machine learning tool is devised to predict within a fraction of a millisecond if a model is excluded or not directly from the model parameters. A first example is SUSY-AI, trained on the phenomenological supersymmetric standard model (pMSSM). About 300, 000 pMSSM model sets - each tested against 200 signal regions by ATLAS - have been used to train and validate SUSY-AI. The code is currently able to reproduce the ATLAS exclusion regions in 19 dimensions with an accuracy of at least 93%. It has been validated further within the constrained MSSM and the minimal natural supersymmetric model, again showing high accuracy. SUSY-AI and its future BSM derivatives will help to solve the problem of recasting LHC results for any model of new physics. SUSY-AI can be downloaded from http://susyai.hepforge.org/. An on-line interface to the program for quick testing purposes can be found at http://www.susy-ai.org/. (orig.)

  3. The BSM-AI project: SUSY-AI-generalizing LHC limits on supersymmetry with machine learning

    Science.gov (United States)

    Caron, Sascha; Kim, Jong Soo; Rolbiecki, Krzysztof; de Austri, Roberto Ruiz; Stienen, Bob

    2017-04-01

    A key research question at the Large Hadron Collider is the test of models of new physics. Testing if a particular parameter set of such a model is excluded by LHC data is a challenge: it requires time consuming generation of scattering events, simulation of the detector response, event reconstruction, cross section calculations and analysis code to test against several hundred signal regions defined by the ATLAS and CMS experiments. In the BSM-AI project we approach this challenge with a new idea. A machine learning tool is devised to predict within a fraction of a millisecond if a model is excluded or not directly from the model parameters. A first example is SUSY-AI, trained on the phenomenological supersymmetric standard model (pMSSM). About 300, 000 pMSSM model sets - each tested against 200 signal regions by ATLAS - have been used to train and validate SUSY-AI. The code is currently able to reproduce the ATLAS exclusion regions in 19 dimensions with an accuracy of at least 93%. It has been validated further within the constrained MSSM and the minimal natural supersymmetric model, again showing high accuracy. SUSY-AI and its future BSM derivatives will help to solve the problem of recasting LHC results for any model of new physics. SUSY-AI can be downloaded from http://susyai.hepforge.org/. An on-line interface to the program for quick testing purposes can be found at http://www.susy-ai.org/.

  4. Categorical vowel perception enhances the effectiveness and generalization of auditory feedback in human-machine-interfaces.

    Directory of Open Access Journals (Sweden)

    Eric Larson

    Full Text Available Human-machine interface (HMI designs offer the possibility of improving quality of life for patient populations as well as augmenting normal user function. Despite pragmatic benefits, utilizing auditory feedback for HMI control remains underutilized, in part due to observed limitations in effectiveness. The goal of this study was to determine the extent to which categorical speech perception could be used to improve an auditory HMI. Using surface electromyography, 24 healthy speakers of American English participated in 4 sessions to learn to control an HMI using auditory feedback (provided via vowel synthesis. Participants trained on 3 targets in sessions 1-3 and were tested on 3 novel targets in session 4. An "established categories with text cues" group of eight participants were trained and tested on auditory targets corresponding to standard American English vowels using auditory and text target cues. An "established categories without text cues" group of eight participants were trained and tested on the same targets using only auditory cuing of target vowel identity. A "new categories" group of eight participants were trained and tested on targets that corresponded to vowel-like sounds not part of American English. Analyses of user performance revealed significant effects of session and group (established categories groups and the new categories group, and a trend for an interaction between session and group. Results suggest that auditory feedback can be effectively used for HMI operation when paired with established categorical (native vowel targets with an unambiguous cue.

  5. The BSM-AI project: SUSY-AI - Generalizing LHC limits on Supersymmetry with Machine Learning

    CERN Document Server

    Caron, Sascha; Rolbiecki, Krzysztof; de Austri, Roberto Ruiz; Stienen, Bob

    2016-01-01

    A key research question at the Large Hadron Collider (LHC) is the test of models of new physics. Testing if a particular parameter set of such a model is excluded by LHC data is a challenge: It requires the time consuming generation of scattering events, the simulation of the detector response, the event reconstruction, cross section calculations and analysis code to test against several hundred signal regions defined by the ATLAS and CMS experiment. In the BSM-AI project we attack this challenge with a new approach. Machine learning tools are thought to predict within a fraction of a millisecond if a model is excluded or not directly from the model parameters. A first example is SUSY-AI, trained on the phenomenological supersymmetric standard model (pMSSM). About 300,000 pMSSM model sets - each tested with 200 signal regions by ATLAS - have been used to train and validate SUSY-AI. The code is currently able to reproduce the ATLAS exclusion regions in 19 dimensions with an accuracy of at least 93 percent. It ...

  6. Analysis of machining and machine tools

    CERN Document Server

    Liang, Steven Y

    2016-01-01

    This book delivers the fundamental science and mechanics of machining and machine tools by presenting systematic and quantitative knowledge in the form of process mechanics and physics. It gives readers a solid command of machining science and engineering, and familiarizes them with the geometry and functionality requirements of creating parts and components in today’s markets. The authors address traditional machining topics, such as: single and multiple point cutting processes grinding components accuracy and metrology shear stress in cutting cutting temperature and analysis chatter They also address non-traditional machining, such as: electrical discharge machining electrochemical machining laser and electron beam machining A chapter on biomedical machining is also included. This book is appropriate for advanced undergraduate and graduate mechani cal engineering students, manufacturing engineers, and researchers. Each chapter contains examples, exercises and their solutions, and homework problems that re...

  7. Analysis of the effect of ultrasonic vibrations on the performance of micro-electrical discharge machining of A2 tool steel

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2016-01-01

    The application of ultrasonic vibrations to a workpiece or tool is a novel hybrid approach in micro-electrical discharge machining. The advantages of this method include effective flushing out of debris, higher machining efficiency and lesser short-circuits during machining. This paper presents...... a systematic analysis of the influence of kinetic effects of the ultrasonic vibrations on the material removal rate (MRR) and tool electrode wear rate (TWR). The tool wear ratio was estimated for the process at all processing conditions. The maximum variation in tool wear ratio is observed to be 82%. Therefore......, MRR and TWR were independently analyzed by using three scientific tools: i) AOM plots, ii) interaction plots and iii) three-dimensional scatter plots. The increase in MRR is 47% corresponding to an increase in the maximum power of vibrations by 30%. The ultrasonic vibrations are found to be very...

  8. Effect of hole geometry and Electric-Discharge Machining (EDM) on airflow rates through small diameter holes in turbine blade material

    Science.gov (United States)

    Hippensteele, S. A.; Cochran, R. P.

    1980-01-01

    The effects of two design parameters, electrode diameter and hole angle, and two machine parameters, electrode current and current-on time, on air flow rates through small-diameter (0.257 to 0.462 mm) electric-discharge-machined holes were measured. The holes were machined individually in rows of 14 each through 1.6 mm thick IN-100 strips. The data showed linear increase in air flow rate with increases in electrode cross sectional area and current-on time and little change with changes in hole angle and electrode current. The average flow-rate deviation (from the mean flow rate for a given row) decreased linearly with electrode diameter and increased with hole angle. Burn time and finished hole diameter were also measured.

  9. Electrical Discharge Machining of Al (6351-5% SiC-10% B4C Hybrid Composite: A Grey Relational Approach

    Directory of Open Access Journals (Sweden)

    S. Suresh Kumar

    2014-01-01

    Full Text Available The goal of the present experimental work is to optimize the electrical discharge machining (EDM parameters of aluminum alloy (Al 6351 matrix reinforced with 5 wt.% silicon carbide (SiC and 10 wt.% boron carbide (B4C particles fabricated through the stir casting route. Multiresponse optimization was carried out through grey relational analysis (GRA with an objective to minimize the machining characteristics, namely electrode wear ratio (EWR, surface roughness (SR and power consumption (PC. The optimal combination of input parameters is identified, which shows the significant enhancement in process characteristics. Contributions of each machining parameter to the responses are calculated using analysis of variance (ANOVA. The result shows that the pulse current contributes more (83.94% to affecting the combined output responses.

  10. 30 CFR 75.523-1 - Deenergization of self-propelled electric face equipment installation requirements.

    Science.gov (United States)

    2010-07-01

    ... after December 15, 1974, for self-propelled cutting machines, shuttle cars, battery-powered machines... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Deenergization of self-propelled electric face... Electrical Equipment-General § 75.523-1 Deenergization of self-propelled electric face equipment installation...

  11. 微细电火花加工关键技术及工艺研究%The Key Techniques and Process for Micro-electrical Discharge Machining

    Institute of Scientific and Technical Information of China (English)

    张勇斌; 吉方; 刘广民; 张连新; 吴祉群

    2011-01-01

    文中基于新研发的一套微细电火花精密加工系统μEDM-50,介绍了研发过程中探索出的最小脉宽可以达纳秒级的微能脉冲电源以及一些针对微细电火花加工的特点形成的特殊工艺.微能脉冲电源具有主动消电离环节,可以减少脉间的残余电荷放电,提高加工表面质量;特殊工艺有利于提高系统的加工精度和效率,提高微细电极的安全性.最后,介绍了一些金属零件上典型的微小特征精密加工实验以及放电沉积实验.该系统加工特征的尺寸范围主要介于数十微米到数毫米内.%In the paper, a kind of micro-electrical discharge machining system named μEDM-50 is described. The paper also presents micro-energy pulse power supply whose least width of pulse can reach nanosecond. Some special processes are introduced subsequently. There is an active discharging circuit in the pulse power supply, which can reduce the residual charge to improve the machining quality of surface.The special process is useful to increase the machining precision and efficiency. Furthermore, micro-tool electrode will be safer. The paper fimally gives several typical experiments of machined miniature structures and electrical discharge deposition. The micro-electrical discharge machining system is mainly to manufacture structure whose size varies from dozens of micrometers to several millimeters.

  12. Applications of General Systems Theory to the Development of an Adjustable Tutorial Software Machine.

    Science.gov (United States)

    Vos, Hans J.

    1994-01-01

    Describes the construction of a model of computer-assisted instruction using a qualitative block diagram based on general systems theory (GST) as a framework. Subject matter representation is discussed, and appendices include system variables and system equations of the GST model, as well as an example of developing flexible courseware. (Contains…

  13. A General and Intuitive Approach to Understand and Compare the Torque Production Capability of AC Machines

    DEFF Research Database (Denmark)

    Wang, Dong; Lu, Kaiyuan; Rasmussen, Peter Omand

    2014-01-01

    -frame, through complicated mathematical manipulations. This is a more mathematical approach rather than explaining the physics behind torque production, which even brings a lot of difficulties to specialist. This paper introduces a general and intuitive approach to obtain the dq-frame torque equation of various...

  14. SINGLE MACHINE SCHEDULING WITH CONTROLLABLE PROCESSING TIMES AND COMPRESSION COSTS (Part Ⅱ Heuristics for the General Case)

    Institute of Scientific and Technical Information of China (English)

    Foulds,L.R.; TangGuochun

    1999-01-01

    A single machine scheduling problem with controllable processing times and compression costs is considered. The objective is to find an optimal sequence to minimize the cost ofcompletion times and the cost of compression. The complexity of this problem is still unknown.In Part Ⅱ of this paper,the authors have considered a special case where the compression timesand the compression costs are equal among all jobs. Such a problem appears polynomiafiy solvable by developing an O(n2) algorithm. In this part(Part Ⅱ ),a general case where the controllable processing times and the compression costs are not equal is discussed. Authors proposehere two heuristics with the first based on some previous work and the second based on the algorithm developed in Part Ⅱ . Computational results are presented to show the efficiency and therobustness of these heuristics.

  15. An improved FEM model for computing transport AC loss in coils made of RABiTS YBCO coated conductors for electric machines

    DEFF Research Database (Denmark)

    Ainslie, Mark D; Rodriguez Zermeno, Victor Manuel; Hong, Zhiyong

    2011-01-01

    AC loss can be a significant problem for any applications that utilize or produce an AC current or magnetic field, such as an electric machine. The authors investigate the electromagnetic properties of high temperature superconductors with a particular focus on the AC loss in superconducting coils...... Superconductivity Group's all-superconducting permanent magnet synchronous motor design. To validate the modeling results, the transport AC loss of a stator coil is measured using an electrical method based on inductive compensation by means of a variable mutual inductance. Finally, the implications of the findings...... on the performance of the motor are discussed....

  16. Defense Logistics Agency Aviation Generally Purchased SoleSource Spare Parts From the General Electric Company at Fair and Reasonable Prices, but Improvements Could Be Made (Redacted)

    Science.gov (United States)

    2015-07-24

    including: • FAR Subpart 2.1, “ Definitions ;” • FAR Part 10, “ Market Research;” • DFARS Subpart 215.4, “Contract Pricing ;” • DFARS PGI 212.1...Defense Logistics Agency Aviation Generally Purchased Sole‑Source Spare Parts From the General Electric Company at Fair and Reasonable Prices , but...Purchased Sole‑Source Spare Parts From the General Electric Company at Fair and Reasonable Prices , but Improvements Could Be Made Visit us at

  17. Reliable prediction of electric spark sensitivity of nitramines: a general correlation with detonation pressure.

    Science.gov (United States)

    Keshavarz, Mohammad Hossein; Pouretedal, Hamid Reza; Semnani, Abolfazl

    2009-08-15

    For nitramines, a general correlation has been introduced to predict electric spark sensitivity through detonation pressure. New method uses maximum obtainable detonation pressure as a fundamental relation so that it can be corrected for some nitramines which have some specific molecular structure. There is no need to use crystal density and heat of formation of nitramine explosives for predicting detonation pressure and electric spark sensitivity. The predicted electric spark sensitivities are compared with calculated results on the basis of quantum mechanical computations for some nitramines that latter can be applied. The root mean square (rms) deviations from experiment for new method and the predicted results of complicated quantum mechanical method are 1.18 and 3.49J, respectively.

  18. A Generalized Model for Electrical Power Distribution Feeders’ Contributions to System Reliability Indices

    Directory of Open Access Journals (Sweden)

    Ganiyu A. Ajenikoko

    2014-01-01

    Full Text Available Reliability indices are parametric quantities used to assess the performance levels of electrical power distribution systems. In this work, a generalized quadratic model is developed for electrical power distribution system contributions to system reliability indices using Ikeja, Port-Harcourt, Kaduna and Kano distribution system feeders as case studies. The mean System Average Interruption Duration Index (SAIDI, System Average Interruption Frequency Index (SAIFI and Customer Average Interruption Duration Index (CAIDI contributions to system reliability indices for Ikeja, Port-Harcourt, Kaduna and Kano distribution systems were 0.0033, 0.0026, 0.0033 and 0.0018 respectively due to the fact that a prolonged period of interruptions was recorded on most of the feeders attached to Port-Harcourt and Kano distribution systems making them to be less reliable compared to Ikeja and Kaduna distribution systems. The generalized Quadratic model forms a basis for a good design, planning and maintenance of distribution systems at large.

  19. 76 FR 17447 - Penske Logistics LLC a Subsidiary of General Electric/Penske Corporation Including On-Site Leased...

    Science.gov (United States)

    2011-03-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Penske Logistics LLC a Subsidiary of General Electric/Penske... former workers of Penske Logistics LLC, a subsidiary of General Electric/Penske Corporation, El Paso...

  20. 75 FR 11918 - General Electric Kentucky Glass Plant, Lighting, LLC, Including On-Site Leased Workers From the...

    Science.gov (United States)

    2010-03-12

    ... notice was published in the Federal Register on February 16, 2010 (75 FR 7034). At the request of the... Employment and Training Administration General Electric Kentucky Glass Plant, Lighting, LLC, Including On..., 2009, applicable to workers of General Electric Kentucky Glass Plant, Lighting, LLC, including...

  1. Research of Electric Discharge Machining Approach Based on Intellectual Control%基于智能控制的电火花加工方法的研究

    Institute of Scientific and Technical Information of China (English)

    杨洋; 燕冬; 朱贤峰; 黄金诚; 张杨; 何天

    2013-01-01

    The electric discharge machine (EDM) machining system is a multi-parameter non-linear stochastic system,and presendy,most of the EDM machines are based on the certain parameters machining.This approach of machining was less effective,the main reason was that the EDM parameters could not be improved at following the process and accommodated the different processing environment in the whole process.In order to solve problems above,a machining method based on intelligent control was proposed.The fuzzy controller designed with mathematical tool of Matlab was used to control the discharge gap and adjust the discharge pulse size in order to achieve the purpose of optimizing the discharge status under very bad discharge environment.A series of experiments are made to identify the feasibility of the control method.%电火花成型加工系统是一种多参数非线性的随机系统,而目前,大多数电火花成型加工机床都是采用定参数加工的方式,机床加工效率低,主要原因在于电加工参数不能随着加工进程的推进而改善,以适应整个加工过程中不同的加工环境.为解决上述问题,提出了一种基于智能控制的加工方法;借助数学工具Matlab设计的模糊控制器对放电间隙的控制和在放电环境恶化下对脉间大小的控制以达到优化放电状态的目的.最后通过实验验证了控制方法的可行性.

  2. 电火花线切割机床加工工艺参数的研究%Research on Wire Electrical Discharge Machining Processing Technology Parameters

    Institute of Scientific and Technical Information of China (English)

    杨亚琴

    2012-01-01

    This paper describes the processing mechanism of wire electrical discharge machining, by using orthogonal test, makes optimization design of peak current, pulse width, and intrapulse ratio of wire electrical discharge machining with high cutting rate and low wire wear, reduce the experiment times, shorten the cycle and improve the efficiency and benefit, so as to optimize processing technology parameter, improve the product quality- It concluded the relation of electric parameters and the processing speed, and surface roughness, for providing the basis for further studying on the processing law of wire electrical discharge machining.%本文阐述了电火花线切割机床的加工机理,利用正交试验的方法,对高速走丝电火花线切割机床加工中的峰值电流、脉冲宽度、脉间比等工艺条件进行了试验的优化设计,减少了试验的次数,缩短了实验周期,提高了效率和效益;从而优化了电火花线切割机床加工工艺参数,提高了加工件的质量;得出了电参数与加工速度和表面粗糙度之间的联系,为进一步研究电火花线切割加工工艺规律提供了基础.

  3. Numerical and Experimental Modelling of Gas Flow and Heat Transfer in the Air Gap of an Electric Machine. Part Ⅱ: Grooved Surfaces

    Institute of Scientific and Technical Information of China (English)

    Maunu KUOSA; Petri SALLINEN; Arttu REUNANEN; Jari BACKMAN; Jaakko LARJOLA; Lasse KOSKELAINEN

    2005-01-01

    The study deals with the cooling of a high-speed electric machine through an air gap with numerical and experimental methods. The rotation speed of the test machine is between 5000~40000 r/min and the machine is cooled by a forced gas flow through the air gap. In the previous part of the research the friction coefficient was measured for smooth and grooved stator cases with a smooth rotor. The heat transfer coefficient was recently calculated by a numerical method and measured for a smooth stator-rotor combination. In this report the cases with axial groove slots at the stator and/or rotor surfaces are studied. Numerical flow simulations and measurements have been done for the test machine dimensions at a large velocity range. At constant mass flow rate the heat transfer coefficients by the numerical method attain bigger values with groove slots on the stator or rotor surfaces. The results by the numerical method have been confirmed with measurements. The RdF-sensor was glued to the stator and rotor surfaces to measure the heat flux through the surface, as well as the temperature.

  4. Recent Advances on Permanent Magnet Machines

    Institute of Scientific and Technical Information of China (English)

    诸自强

    2012-01-01

    This paper overviews advances on permanent magnet(PM) brushless machines over last 30 years,with particular reference to new and novel machine topologies.These include current states and trends for surface-mounted and interior PM machines,electrically and mechanically adjusted variable flux PM machines including memory machine,hybrid PM machines which uniquely integrate PM technology into induction machines,switched and synchronous reluctance machines and wound field machines,Halbach PM machines,dual-rotor PM machines,and magnetically geared PM machines,etc.The paper highlights their features and applications to various market sectors.

  5. Current density in generalized Fibonacci superlattices under a uniform electric field.

    Science.gov (United States)

    Panchadhyayee, P; Biswas, R; Khan, Arif; Mahapatra, P K

    2008-07-09

    We present an exhaustive study on tunneling and electrical conduction in an electrically biased GaAs-Al(y)Ga(1-y)As generalized Fibonacci superlattice. The study is based on transfer matrix formalism using an Airy function approach and provides an exact calculation of the current density in the case of quasi-periodic multibarrier systems. The results suggest the use of such quasi-periodic systems in perfect band-pass or band-eliminator (of extremely low width) circuitry. We have clearly demonstrated the resonance-type peaks and negative differential conductivity regimes in such systems. It has also been found that quasi-periodicity favors sharp negative differential conductivity peaks compared to those in periodic superlattices and thus have profound importance in device applications.

  6. Generalized Flow Tracing for the Analysis of Networked Renewable Electricity Systems

    CERN Document Server

    Hörsch, Jonas; Becker, Sarah; Schramm, Stefan; Greiner, Martin

    2016-01-01

    Flow allocation methods represent a valuable tool set to analyze the power flows in networked electricity systems. Based on this flow allocation, the costs associated with the usage of the underlying network infrastructure can be assigned to the users of the electricity system. This paper presents a generalization of the flow tracing method that is applicable to arbitrary compositions of inflow appearing naturally in aggregated networks. The composition of inflow is followed from net-generating sources through the network and assigns corresponding shares of the total power flow as well as of the outflow to the net-consuming sinks. We showcase the analytical power of this method for a scenario based on the IEEE 118 bus network and emphasize the need of appropriate aggregating measures, which allow to integrate over whole time series of fluctuating flow patterns.

  7. Hypersphere support vector machines based on generalized multiplicative updates%基于广义乘性规则的支持向量机

    Institute of Scientific and Technical Information of China (English)

    吴青; 刘三阳; 张东友

    2008-01-01

    This paper proposes a novel hypersphere support vector machines (HSVMs) based on generalized multiplicativeupdates. This algorithm can obtain the boundary of hypersphere containing one class of samples by the description of thetraining samples from one class and use this boundary to classify the test samples. The generalized multiplicative updatesare applied to solving boundary optimization programming. Multiplicative updates available are suited for nonnegativequadratic convex programming. The generalized multiplicative updates are derived to box and sum constrained quadraticprogramming in this paper. They provide an extremely straightforward way to implement support vector machines (SVMs)where all variables are updated in parallel. The generalized multiplicative updates converge monotonically to the solution ofthe maximum margin hyperplane. The experiments showthe superiority of our new algorithm.

  8. An improved FEM model for computing transport AC loss in coils made of RABiTS YBCO coated conductors for electric machines

    Science.gov (United States)

    Ainslie, Mark D.; Rodriguez-Zermeno, Victor M.; Hong, Zhiyong; Yuan, Weijia; Flack, Timothy J.; Coombs, Timothy A.

    2011-04-01

    AC loss can be a significant problem for any applications that utilize or produce an AC current or magnetic field, such as an electric machine. The authors investigate the electromagnetic properties of high temperature superconductors with a particular focus on the AC loss in superconducting coils made from YBCO coated conductors for use in an all-superconducting electric machine. This paper presents an improved 2D finite element model for the cross-section of such coils, based on the H formulation. The model is used to calculate the transport AC loss of a racetrack-shaped coil using constant and magnetic field-dependent critical current densities, and the inclusion and exclusion of a magnetic substrate, as found in RABiTS (rolling-assisted biaxially textured substrate) YBCO coated conductors. The coil model is based on the superconducting stator coils used in the University of Cambridge EPEC Superconductivity Group's all-superconducting permanent magnet synchronous motor design. To validate the modeling results, the transport AC loss of a stator coil is measured using an electrical method based on inductive compensation by means of a variable mutual inductance. Finally, the implications of the findings on the performance of the motor are discussed.

  9. 乒乓球捡球机电气控制线路设计%Design of Electrical Control Circuit of Table Tennis Picking Machine

    Institute of Scientific and Technical Information of China (English)

    夏春风; 朱文伟; 高卫群; 马燕平; 王治国

    2016-01-01

    为解决乒乓球训练场所乒乓球的捡拾问题,设计了一种基于PLC和触摸屏的电气控制线路。该电气控制线路应用于乒乓球捡球机,利用PLC和触摸屏程序控制捡球机中的离心风机,离心风机产生的吸力吸取散落于地的乒乓球而实现自动捡球。捡球机实物模型性能测试表明,该捡球机捡球效果良好,平均每分钟捡球可达86个,此为更多捡球机的开发提供了借鉴和参考。%In order to solve the problem of table tennis picking in the table tennis court, an electrical control circuit based on PLC and touch screen was designed. The electrical control circuit was used for the table tennis picking machines. The table tennis balls scattered on the ground could be automatically picked up by a centrifugal fan in the table tennis picking machines. The centrifugal fan was controlled by PLC and touch screen program.The performance testing on the practical model of picking machine shows that the table tennis picking machines works well and average picks up table tennis up to 86 per minute,which provide reference for development of other moretypes of ball picking robots.

  10. Design principles of metal-cutting machine tools

    CERN Document Server

    Koenigsberger, F

    1964-01-01

    Design Principles of Metal-Cutting Machine Tools discusses the fundamentals aspects of machine tool design. The book covers the design consideration of metal-cutting machine, such as static and dynamic stiffness, operational speeds, gearboxes, manual, and automatic control. The text first details the data calculation and the general requirements of the machine tool. Next, the book discusses the design principles, which include stiffness and rigidity of the separate constructional elements and their combined behavior under load, as well as electrical, mechanical, and hydraulic drives for the op

  11. Comparing artificial neural networks, general linear models and support vector machines in building predictive models for small interfering RNAs.

    Directory of Open Access Journals (Sweden)

    Kyle A McQuisten

    Full Text Available BACKGROUND: Exogenous short interfering RNAs (siRNAs induce a gene knockdown effect in cells by interacting with naturally occurring RNA processing machinery. However not all siRNAs induce this effect equally. Several heterogeneous kinds of machine learning techniques and feature sets have been applied to modeling siRNAs and their abilities to induce knockdown. There is some growing agreement to which techniques produce maximally predictive models and yet there is little consensus for methods to compare among predictive models. Also, there are few comparative studies that address what the effect of choosing learning technique, feature set or cross validation approach has on finding and discriminating among predictive models. PRINCIPAL FINDINGS: Three learning techniques were used to develop predictive models for effective siRNA sequences including Artificial Neural Networks (ANNs, General Linear Models (GLMs and Support Vector Machines (SVMs. Five feature mapping methods were also used to generate models of siRNA activities. The 2 factors of learning technique and feature mapping were evaluated by complete 3x5 factorial ANOVA. Overall, both learning techniques and feature mapping contributed significantly to the observed variance in predictive models, but to differing degrees for precision and accuracy as well as across different kinds and levels of model cross-validation. CONCLUSIONS: The methods presented here provide a robust statistical framework to compare among models developed under distinct learning techniques and feature sets for siRNAs. Further comparisons among current or future modeling approaches should apply these or other suitable statistically equivalent methods to critically evaluate the performance of proposed models. ANN and GLM techniques tend to be more sensitive to the inclusion of noisy features, but the SVM technique is more robust under large numbers of features for measures of model precision and accuracy. Features

  12. 线切割加工质量的分析及改善措施%Analysis and improvement for wire-cutting electrical discharge machining

    Institute of Scientific and Technical Information of China (English)

    魏妍丽

    2015-01-01

    线切割加工在模具制造业中常用于加工精密、微细的模具零件。通过介绍线切割的加工原理,研究了线切割加工过程容易产生的加工质量缺陷,分析了加工面变形与开裂、变质层及表面粗糙度产生的原因,提出了进一步提高工件表面质量的改善措施和方法。实践中可以通过合理选材、优化电参数、选择正确的加工路线等方面综合分析和控制线切割加工,在保证生产率的前提下,改善和提高线切割加工质量。%Wire‐cutting electrical discharge machining is commonly used in the precision and micro‐parts machining process for the mould .Through the introduction of wire‐cutting ma‐chining principle ,the processing defects during wire‐cutting machining are analyzed ,such as the deformation and cracking on the machined surface ,the generation of metamorphic layer and rough surface .Some measures are also proposed to improve the surface quality . Practice proves that appropriate materials , optimal discharge parameters and reasonable cutting paths can improve the machining quality .

  13. Simulation of the preliminary General Electric SP-100 space reactor concept using the ATHENA computer code

    Science.gov (United States)

    Fletcher, C. D.

    The capability to perform thermal-hydraulic analyses of a space reactor using the ATHENA computer code is demonstrated. The fast reactor, liquid-lithium coolant loops, and lithium-filled heat pipes of the preliminary General electric SP-100 design were modeled with ATHENA. Two demonstration transient calculations were performed simulating accident conditions. Calculated results are available for display using the Nuclear Plant Analyzer color graphics analysis tool in addition to traditional plots. ATHENA-calculated results appear reasonable, both for steady state full power conditions, and for the two transients. This analysis represents the first known transient thermal-hydraulic simulation using an integral space reactor system model incorporating heat pipes.

  14. A generalized transformation to convert an arbitrary perfect electric conductor into another arbitrary dielectric object

    Energy Technology Data Exchange (ETDEWEB)

    Huang Lujun; Zhou Daming; Wang Jian; Li Guanhai; Li Zhifeng; Chen Xiaoshuang; Lu Wei, E-mail: xschen@mail.sitp.ac.cn [National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 200083 Shanghai (China)

    2011-06-15

    A generalized transformation is proposed to design an illusion device. The device can reshape an arbitrarily shaped perfect electrical conductor (PEC) into another dielectric object with arbitrary geometry. Such a device can evolve into an ideal invisibility cloak with non-conformal boundaries if the virtual space is filled with air. Furthermore, the validity of our proposed transformation is confirmed by two specific devices. One is to convert a regular polygonal PEC cylinder into a circular dielectric cylinder. Another one is to reshape a circular PEC cylinder into a regular polygonal dielectric cylinder.

  15. Influence of electrical discharge machining on the tribological characteristics of WC-Co alloys; Influencia de la electroerosion sobre las caracteristicas tribologicas de materiales compuestos WC-Co

    Energy Technology Data Exchange (ETDEWEB)

    Casas, B.; Martinez, E.; Esteve, J.; Anglada, M.; Llanes, L.

    2001-07-01

    The influence of electrical discharge machining (EDM) on the abrasive wear resistance of two WC-10 %{sub w}tCo cemented carbides with different carbide grain size has been studied. Different surface finish conditions were evaluated corresponding to sequential EDM as well as grinding and polishing with diamond. The abrasive wear resistance was determined through microscratch measurements using a nano indentation system. Contrary to the results obtained from hardness measurements, this techniques allows to discern tribological differences among the distinct surface finish conditions studied. Finally, the abrasive wear resistance degradation associated with sequential EDM is discussed as a function of microstructure in terms of a damage parameters. (Author) 9 refs.

  16. REACTOR AND SHIELD PHYSICS. Comprehensive Technical Report, General Electric Direct-Air-Cycle, Aircraft Nuclear Propulsion Program.

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, W.E.; Simpson, J.D.

    1962-01-01

    This volume is one of twenty-one summarizing the Aircraft Nuclear Propulsion Program of the General Electric Company. This volume describes the experimental and theoretical work accomplished in the areas of reactor and shield physics.

  17. Parametric Optimization of Wire Electrical Discharge Machining of Powder Metallurgical Cold Worked Tool Steel using Taguchi Method

    Science.gov (United States)

    Sudhakara, Dara; Prasanthi, Guvvala

    2016-08-01

    Wire Cut EDM is an unconventional machining process used to build components of complex shape. The current work mainly deals with optimization of surface roughness while machining P/M CW TOOL STEEL by Wire cut EDM using Taguchi method. The process parameters of the Wire Cut EDM is ON, OFF, IP, SV, WT, and WP. L27 OA is used for to design of the experiments for conducting experimentation. In order to find out the effecting parameters on the surface roughness, ANOVA analysis is engaged. The optimum levels for getting minimum surface roughness is ON = 108 µs, OFF = 63 µs, IP = 11 A, SV = 68 V and WT = 8 g.

  18. Modeling and multi-objective optimization of powder mixed electric discharge machining process of aluminum/alumina metal matrix composite

    Directory of Open Access Journals (Sweden)

    Gangadharudu Talla

    2015-09-01

    Full Text Available Low material removal rate (MRR and high surface roughness values hinder large-scale application of electro discharge machining (EDM in the fields like automobile, aerospace and medical industry. In recent years, however, EDM has gained more significance in these industries as the usage of difficult-to-machine materials including metal matrix composites (MMCs increased. In the present work, an attempt has been made to fabricate and machine aluminum/alumina MMC using EDM by adding aluminum powder in kerosene dielectric. Results showed an increase in MRR and decrease in surface roughness (Ra compared to those for conventional EDM. Semi empirical models for MRR and Ra based on machining parameters and important thermo physical properties were established using a hybrid approach of dimensional and regression analysis. A multi response optimization was also performed using principal component analysis-based grey technique (Grey-PCA to determine optimum settings of process parameters for maximum MRR and minimum Ra within the experimental range. The recommended setting of process parameters for the proposed process has been found to be powder concentration (Cp = 4 g/l, peak current (Ip = 3 A, pulse on time (Ton = 150 μs and duty cycle (Tau = 85%.

  19. Electric Hydraulic Switch Machine Spindle Balancing Valve Start Cylinder Device%电动液压转辙机梭式平衡阀启动缸装置

    Institute of Scientific and Technical Information of China (English)

    许丽娟

    2015-01-01

    Applicable to the transformation of railway switch electric hydraulic switch machine's spindle type balance valve start cylinder device can improve the starting characteristics of electric hydraulic switch machine AC motor, and rebound phenomenon of cylinder can be eliminated; can be used in all kinds of turnout electro-hydraulic conversion equipment, can also be used in hydraulic system change good motor starting performance and the hydraulic system on both sides of the oil circuit pressure equilibrium.%适用于铁路道岔电动液压转辙机转换的梭式平衡阀启动缸装置既可改善电动液压转辙机交流电机启动特性,又可消除油缸反弹现象;既适用于各种道岔电液转换设备,也适用于液压系统改善电机启动性能和液压系统两侧油路压力的平衡。

  20. Models for general phase change phenomena in heat exchangers and in industrial processes affected by applying an electric field

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Y.Y. [Nottingham Trent University Burton Street, Dept. of Mechinal and Manufacturing Engineering (United Kingdom)

    1999-07-01

    This paper describes the theoretical models for general phase change phenomena in heat exchangers and in industrial processes affected by applying an electric field. The models are on the basis of nucleation and surface fluctuation theories to study the generality of phase change processes under the action of an electric field. Theoretical analysis is carried out and highlights the effect of an electric field on phase change processes from an existing phase to a new phase. The analysis has shown that a critical value of the filed strength could be found theoretically for a certain phase change process. This could be a mechanism of control the processes. (authors)

  1. Electrical efficiency: case study of electric motors at machines room of a slaughterhouse in the state of Sao Paulo; Eficiencia eletrica: estudo de caso dos motores eletricos da sala de maquinas de um frigorifico no estado de Sao Paulo

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Luiz A. [Universidade Estadual de Campinas (FEAGRI/UNICAMP), SP (Brazil). Fac. de Engenharia Agricola. Conselho Integrado de Infraestrutura Rural], E-mail: rossi@agri.unicamp.br; Silva, Roberto P.B. da; Barros, Regiane S. de [Universidade Estadual de Campinas (FEM/UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica

    2010-07-01

    To estimate the potential for energy saving in cold compressor motor of a food industry, a study was conducted in a slaughterhouse in the state of Sao Paulo. It was analyzed only the engine room of the company because according to measurements this one corresponds approximately 97% of all electricity consumption of the unit. It was found that the electrical efficiency indices were low, demonstrating the possibilities for adoption of conservation measures and the rationalization of electric energy. It was evident that the establishment of an efficiency study to change the electrical equipment used was feasible and, therefore, was demonstrated and proposed a new arrangement for the current system. Soon after the diagnosis of the use of electricity was found that from the six Machinery, five were oversized. Then it was suggested to replace these machines by others with lower power and greater efficiency, as well as conducted an analysis of technical and economic feasibility of the project, demonstrating the possibilities for the rational use of energy and the optimization of financial resources company (author)

  2. General electrokinetic model for concentrated suspensions in aqueous electrolyte solutions: Electrophoretic mobility and electrical conductivity in static electric fields.

    Science.gov (United States)

    Carrique, Félix; Ruiz-Reina, Emilio; Roa, Rafael; Arroyo, Francisco J; Delgado, Ángel V

    2015-10-01

    In recent years different electrokinetic cell models for concentrated colloidal suspensions in aqueous electrolyte solutions have been developed. They share some of its premises with the standard electrokinetic model for dilute colloidal suspensions, in particular, neglecting both the specific role of the so-called added counterions (i.e., those released by the particles to the solution as they get charged), and the realistic chemistry of the aqueous solution on such electrokinetic phenomena as electrophoresis and electrical conductivity. These assumptions, while having been accepted for dilute conditions (volume fractions of solids well below 1%, say), are now questioned when dealing with concentrated suspensions. In this work, we present a general electrokinetic cell model for such kind of systems, including the mentioned effects, and we also carry out a comparative study with the standard treatment (the standard solution only contains the ions that one purposely adds, without ionic contributions from particle charging or water chemistry). We also consider an intermediate model that neglects the realistic aqueous chemistry of the solution but accounts for the correct contribution of the added counterions. The results show the limits of applicability of the classical assumptions and allow one to better understand the relative role of the added counterions and ions stemming from the electrolyte in a realistic aqueous solution, on electrokinetic properties. For example, at low salt concentrations the realistic effects of the aqueous solution are the dominant ones, while as salt concentration is increased, it is this that progressively takes the control of the electrokinetic response for low to moderate volume fractions. As expected, if the solids concentration is high enough the added counterions will play the dominant role (more important the higher the particle surface charge), no matter the salt concentration if it is not too high. We hope this work can help in

  3. The TCSC (Thyristor Controlled Series Compensator) in a multi machine electric power system: the effects on the synchronizing power; O TCSC em um sistema de energia eletrica multimaquinas: os efeitos sobre a potencia sincronizante

    Energy Technology Data Exchange (ETDEWEB)

    Silva, J.C.; Colvara, L.D. [Universidade Estadual Paulista (FEIS/UNESP), Ilha Solteira, SP (Brazil). Dept. de Engenharia Eletrica], Emails: jadiel_silva@hotmail.com, laurence@dee.feis.unesp.br

    2009-07-01

    The problem of stability of electric power systems, from the standpoint of ability to sync and how FACTS (Flexible Alternating Current Transmission Systems) devices affect this ability in particular the TSCS (Thyristor Controlled Series Compensator) inserted into an environment multi machine, is addressed. The effects of this device on the power synchronizing are considered through analysis of the matrix admittance of the bar, focusing on the transfer admittances between machines.

  4. PLC在光纤着色机电气控制系统中的应用%An Electric Control System of Fiber Colouring Machine with Progrmmable Logic Controller

    Institute of Scientific and Technical Information of China (English)

    黄友锐; 魏庆农; 余强; 江平

    2000-01-01

    In this paper,the control system of fiber colouring machine is introduced in detail. The application of programmable logic controller in the electric control sys tem of fiber colouring machine is explained.%本文介绍了光纤着色机控制系统的总体方案,着重叙述了可编程控制器在光纤着色机电气控制系统中的应用。

  5. A generalized finite difference method for modeling cardiac electrical activation on arbitrary, irregular computational meshes.

    Science.gov (United States)

    Trew, Mark L; Smaill, Bruce H; Bullivant, David P; Hunter, Peter J; Pullan, Andrew J

    2005-12-01

    A generalized finite difference (GFD) method is presented that can be used to solve the bi-domain equations modeling cardiac electrical activity. Classical finite difference methods have been applied by many researchers to the bi-domain equations. However, these methods suffer from the limitation of requiring computational meshes that are structured and orthogonal. Finite element or finite volume methods enable the bi-domain equations to be solved on unstructured meshes, although implementations of such methods do not always cater for meshes with varying element topology. The GFD method solves the bi-domain equations on arbitrary and irregular computational meshes without any need to specify element basis functions. The method is useful as it can be easily applied to activation problems using existing meshes that have originally been created for use by finite element or finite difference methods. In addition, the GFD method employs an innovative approach to enforcing nodal and non-nodal boundary conditions. The GFD method performs effectively for a range of two and three-dimensional test problems and when computing bi-domain electrical activation moving through a fully anisotropic three-dimensional model of canine ventricles.

  6. General Equilibrium Analysis of Electricity Market Liberalization in Singapore: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Fenglong XIAO

    2011-12-01

    Full Text Available The liberalization in electricity market in Singapore has being undertaken for more than 15 years. This paper evaluates the influence of competition policies by computable general equilibrium (CGE model. Instead of the direct measurement of the impact of competition policy, the benefit of liberalization is reflected by the simulation of a hypothetical regulatory condition. Comparing to the regulatory scenario, simulation result implies the current liberalization raises GDP and exchange rate significantly, but also leaves the tradeoff between higher national income and lower consumer welfare to government. If such choice of economic policy is necessary for political demand, a formal legal framework is required to enforce the restoration of the economy from regulatory restrictions.

  7. Study on Electrical Discharge Machining Technology of Polycrystalline Cubic Boron Nitride Cutting Tool%聚晶立方氮化硼刀具刃口放电加工工艺研究

    Institute of Scientific and Technical Information of China (English)

    贾云海; 李建钢; 朱立新; 宋英杰

    2012-01-01

    通过调整电火花加工的主要放电参数(脉冲宽度和加工电流),对聚晶立方氮化硼(PCBN)样刀进行放电加工,进而对样刀刃口表面进行X射线衍射分析,并在扫描电子显微镜下观察其表层结构及能谱分析.通过对加工后样刀表面变质层主要成分及产生原因的分析,总结了脉冲宽度和加工电流对样刀表面变质层厚度、刃口表面粗糙度影响的关系曲线,为制定精密快速放电加工PCBN刀具的工艺提供了重要依据.%The samples of polycrystalline cubic boron nitride(PCBN) cutting tool were machined by adjusting the main parameters of electrical discharge machining (EDM). After the machining, the phases were analyzed by X-ray diffraction analyzer and the surface layer microstructure was observed by scanning electronic microscope. The fundamental component of machined PCBN cutting tool affected layer was obtained and the reason of begetting affected layer was analyzed. The relationship curves between pulse width, working electric current and depth affected layer, blade surface roughness were summarized. The results showed that to adjust electrical discharge machining parameters, such as decreasing pulse width or machining electric currents, can reduce the depth of affect layer and improve blade surface roughness. These researches provide valuable test reference for drawing up electrical discharge machining technology of PCBN cutting tool.

  8. 75 FR 1622 - Decision To Evaluate a Petition To Designate a Class of Employees for the General Electric...

    Science.gov (United States)

    2010-01-12

    ... evaluation, is as follows: Facility: General Electric Company. Location: Evendale, Ohio. Job Titles and/or... HUMAN SERVICES Decision To Evaluate a Petition To Designate a Class of Employees for the General...: Notice. SUMMARY: HHS gives notice as required by 42 CFR 83.12(e) of a decision to evaluate a petition to...

  9. Conception d'une methodologie generale d'evaluation de la traduction automatique (Conception of a General Methodology for Evaluating Machine Translation).

    Science.gov (United States)

    van Slype, Georges

    1982-01-01

    It is proposed that assessment of human translation versus machine translation programs use methods and criteria that measure efficiency and cost effectiveness and are efficient and cost-effective in themselves. A variety of methods and criteria are evaluated and discussed. (MSE)

  10. Machining of fiber reinforced composites

    Science.gov (United States)

    Komanduri, Ranga; Zhang, Bi; Vissa, Chandra M.

    Factors involved in machining of fiber-reinforced composites are reviewed. Consideration is given to properties of composites reinforced with boron filaments, glass fibers, aramid fibers, carbon fibers, and silicon carbide fibers and to polymer (organic) matrix composites, metal matrix composites, and ceramic matrix composites, as well as to the processes used in conventional machining of boron-titanium composites and of composites reinforced by each of these fibers. Particular attention is given to the methods of nonconventional machining, such as laser machining, water jet cutting, electrical discharge machining, and ultrasonic assisted machining. Also discussed are safety precautions which must be taken during machining of fiber-containing composites.

  11. A Human-machine-interface Integrating Low-cost Sensors with a Neuromuscular Electrical Stimulation System for Post-stroke Balance Rehabilitation.

    Science.gov (United States)

    Kumar, Deepesh; Das, Abhijit; Lahiri, Uttama; Dutta, Anirban

    2016-04-12

    A stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow to brain thereby preventing delivery of oxygen and nutrients. About half of the stroke survivors are left with some degree of disability. Innovative methodologies for restorative neurorehabilitation are urgently required to reduce long-term disability. The ability of the nervous system to reorganize its structure, function and connections as a response to intrinsic or extrinsic stimuli is called neuroplasticity. Neuroplasticity is involved in post-stroke functional disturbances, but also in rehabilitation. Beneficial neuroplastic changes may be facilitated with non-invasive electrotherapy, such as neuromuscular electrical stimulation (NMES) and sensory electrical stimulation (SES). NMES involves coordinated electrical stimulation of motor nerves and muscles to activate them with continuous short pulses of electrical current while SES involves stimulation of sensory nerves with electrical current resulting in sensations that vary from barely perceivable to highly unpleasant. Here, active cortical participation in rehabilitation procedures may be facilitated by driving the non-invasive electrotherapy with biosignals (electromyogram (EMG), electroencephalogram (EEG), electrooculogram (EOG)) that represent simultaneous active perception and volitional effort. To achieve this in a resource-poor setting, e.g., in low- and middle-income countries, we present a low-cost human-machine-interface (HMI) by leveraging recent advances in off-the-shelf video game sensor technology. In this paper, we discuss the open-source software interface that integrates low-cost off-the-shelf sensors for visual-auditory biofeedback with non-invasive electrotherapy to assist postural control during balance rehabilitation. We demonstrate the proof-of-concept on healthy volunteers.

  12. Refrigerating machine oil

    Energy Technology Data Exchange (ETDEWEB)

    Nozawa, K.

    1981-03-17

    Refrigerating machine oil to be filled in a sealed motorcompressor unit constituting a refrigerating cycle system including an electric refrigerator, an electric cold-storage box, a small-scaled electric refrigerating show-case, a small-scaled electric cold-storage show-case and the like, is arranged to have a specifically enhanced property, in which smaller initial driving power consumption of the sealed motor-compressor and easier supply of the predetermined amount of the refrigerating machine oil to the refrigerating system are both guaranteed even in a rather low environmental temperature condition.

  13. Advanced Analysis of Nontraditional Machining

    CERN Document Server

    Tsai, Hung-Yin

    2013-01-01

    Nontraditional machining utilizes thermal, chemical, electrical, mechanical and optical sources of energy to form and cut materials. Advanced Analysis of Nontraditional Machining explains in-depth how each of these advanced machining processes work, their machining system components, and process variables and industrial applications, thereby offering advanced knowledge and scientific insight. This book also documents the latest and frequently cited research results of a few key nonconventional machining processes for the most concerned topics in industrial applications, such as laser machining, electrical discharge machining, electropolishing of die and mold, and wafer processing for integrated circuit manufacturing. This book also: Fills the gap of the advanced knowledge of nonconventional machining between industry and research Documents latest and frequently cited research of key nonconventional machining processes for the most sought after topics in industrial applications Demonstrates advanced multidisci...

  14. Comparative investigation of vibration and current monitoring for prediction of mechanical and electrical faults in induction motor based on multiclass-support vector machine algorithms

    Science.gov (United States)

    Gangsar, Purushottam; Tiwari, Rajiv

    2017-09-01

    This paper presents an investigation of vibration and current monitoring for effective fault prediction in induction motor (IM) by using multiclass support vector machine (MSVM) algorithms. Failures of IM may occur due to propagation of a mechanical or electrical fault. Hence, for timely detection of these faults, the vibration as well as current signals was acquired after multiple experiments of varying speeds and external torques from an experimental test rig. Here, total ten different fault conditions that frequently encountered in IM (four mechanical fault, five electrical fault conditions and one no defect condition) have been considered. In the case of stator winding fault, and phase unbalance and single phasing fault, different level of severity were also considered for the prediction. In this study, the identification has been performed of the mechanical and electrical faults, individually and collectively. Fault predictions have been performed using vibration signal alone, current signal alone and vibration-current signal concurrently. The one-versus-one MSVM has been trained at various operating conditions of IM using the radial basis function (RBF) kernel and tested for same conditions, which gives the result in the form of percentage fault prediction. The prediction performance is investigated for the wide range of RBF kernel parameter, i.e. gamma, and selected the best result for one optimal value of gamma for each case. Fault predictions has been performed and investigated for the wide range of operational speeds of the IM as well as external torques on the IM.

  15. Optimized design of a high-power-density PM-assisted synchronous reluctance machine with ferrite magnets for electric vehicles

    Directory of Open Access Journals (Sweden)

    Liu Xiping

    2017-06-01

    Full Text Available This paper proposes a permanent magnet (PM-assisted synchronous reluctance machine (PMASynRM using ferrite magnets with the same power density as rareearth PM synchronous motors employed in Toyota Prius 2010. A suitable rotor structure for high torque density and high power density is discussed with respect to the demagnetization of ferrite magnets, mechanical strength and torque ripple. Some electromagnetic characteristics including torque, output power, loss and efficiency are calculated by 2-D finite element analysis (FEA. The analysis results show that a high power density and high efficiency of PMASynRM are obtained by using ferrite magnets.

  16. Electrical machines, in particular generators: superconductor technology in competition with improved conventional technology; Elektrische Maschinen, insbesondere Generatoren: Supraleiter-Technologie im Wettbewerb mit verbesserter konventioneller Technologie

    Energy Technology Data Exchange (ETDEWEB)

    Joho, R.; Ginet, C.; Schleussinger, A.

    2006-07-01

    This final report for the Swiss Federal Office of Energy (SFOE) summarises work done within the framework of a second project on the use of superconductor technology and conventional technology in electrical machines. The two variants, a generator using second-generation high-temperature superconductors (HTSC) and one using improved conventional technology are described and compared. The use of various coolants for the windings of generators of various types and usage is described and the optimisation of winding-geometry is discussed. The refrigeration equipment used to provide low-temperature coolant is looked at and the energy balance for the combination of generator and cooling system is discussed. The conclusions drawn by the project are presented and the advantages offered by both variants are discussed.

  17. Research of physical and mechanical properties of electric steel, providing for the grate bars of the roasting and sintering machines improved operational stability

    Directory of Open Access Journals (Sweden)

    Олександр Давидович Учитель

    2016-07-01

    Full Text Available The grate bars of the conveyor roasting and sintering machines work in severe, aggressive dust and gaseous medium, under cyclic modes «heating-cooling», as well as under the load of iron ore agglomerates what results in bending stress in the body of the grate bar. Consequently, electric steel grate bar must be resistant to chemical and erosion processes, high cyclically changing temperature and have high mechanical properties. The paper discusses the conditions of the grate bars of conveyor roasting and sintering machines wear, depending on the adopted loading schemes. The materials to be processed can be loaded directly from the hopper (direct download or through the use of a feeder (drum-type feeder, roller, etc.. A simplified method to predict the grate bars surface wear on the strength of a number of assumptions has been developed: normal reaction of the pallet surface to the impact of the batch is assumed constant, equal to the maximum of its value when the pallet is in horizontal position; a layer of the batch moves as a rigid body; surface batch layer sliding velocity as related to the pallet surface is taken medium during the relative motion of the layer and equal to the linear velocity of the pallets; the side faces of the grate bars wear is related to related to the surface wear by linear dependence. The dependence of the wear on the friction forces and the steel wear resistance coefficient has been found out

  18. Reciprocating washing machine electric control system design%往复式全自动洗车机电气控制系统设计

    Institute of Scientific and Technical Information of China (English)

    王海祥; 薛峰

    2011-01-01

    First of all,this thesis illustrates the advantage of using reciprocating washing machine.Then the thesis analyzes the car washing procedure by the reciprocating washing machine.According to the procedure,the thesis gives us the mechanical structure design and the electrical setting of the key parts such as horizontal brush,large brush and wind outlet device.In the thesis,the typical electrical motor main circuit design is introduced.At the control part,PLC is used to control the external devices.The authors design the wiring diagram,and give the list of input and output according to the procedure.At last,the authors provide the control software of key parts such as horizontal brush,large brush and wind outlet device.Meanwhile,the authors explain the software de sign.%本文首先对使用往复式全自动洗车机的优点进行了阐述。然后,对往复式全自动洗车机的洗车工艺流程进行了分析,根据工艺流程对横刷、大刷、风口装置等重点部分的机械结构和电气设备设置进行了设计。本文介绍了典型的电机主电路设计。在控制部分,选择plc对外部设备进行控制。根据工艺流程要求,作者画出了plc外部接线图,列出了输入输出列表;最后,给出了横刷、大刷、风口装置这些重点部分控制软件图,并且对软件设计进行了说明。

  19. Study on Approach for Computer-Aided Design and Machining of General Cylindrical Cam Using Relative Velocity and Inverse Kinematics

    Institute of Scientific and Technical Information of China (English)

    Se-Hwan; Park; Byong-Kook; Gu; Joong-Ho; Shin; Geun-Jong; Yoo

    2002-01-01

    Cylindrical Cam Mechanism which is one of the best eq uipments to accomplish an accurate motion transmission is widely used in the fie lds of industries, such as machine tool exchangers, textile machinery and automa tic transfer equipments. This paper proposes a new approach for the shape design and manufacturing of the cylindrical cam. The design approach uses the relative velocity concept and the manufacturing approach uses the inverse kinematics concept. For the shape desig n, the contact points betw...

  20. Characterization of waferstepper and process related front- to backwafer overlay errors in bulk micro machining using electrical overlay test structures

    NARCIS (Netherlands)

    Van Zeijl, H.W.; Bijnen, F.G.C.; Slabbekoorn, J.

    2004-01-01

    To validate the Front- To Backwafer Alignment (FTBA) calibration and to investigate process related overlay errors, electrical overlay test structures are used that requires FTBA [1]. Anisotropic KOH etch through the wafer is applied to transfer the backwafer pattern to the frontwafer. Consequently,

  1. The birth of the electric machines: a commentary on Faraday (1832) ‘Experimental researches in electricity’

    Science.gov (United States)

    Al-Khalili, Jim

    2015-01-01

    The history of science is filled with examples of key discoveries and breakthroughs that have been published as landmark texts or journal papers, and to which one can trace the origins of whole disciplines. Such paradigm-shifting publications include Copernicus' De revolutionibus orbium coelestium (1543), Isaac Newton's Philosophiæ Naturalis Principia Mathematica (1687) and Albert Einstein's papers on relativity (1905 and 1915). Michael Faraday's 1832 paper on electromagnetic induction sits proudly among these works and in a sense can be regarded as having an almost immediate effect in transforming our world in a very real sense more than any of the others listed. Here we review the status of the subject—the relationship between magnetism and electricity both before and after Faraday's paper and delve into the details of the key experiments he carried out at the Royal Institution outlining clearly how he discovered the process of electromagnetic induction, whereby an electric current could be induced to flow through a conductor that experiences a changing magnetic field. His ideas would not only enable Maxwell's later development of his theory of classical electromagnetism, but would directly lead to the development of the electric dynamo and electric motor, two technological advances that are the very foundations of the modern world. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750145

  2. Induction machine handbook

    CERN Document Server

    Boldea, Ion

    2002-01-01

    Often called the workhorse of industry, the advent of power electronics and advances in digital control are transforming the induction motor into the racehorse of industrial motion control. Now, the classic texts on induction machines are nearly three decades old, while more recent books on electric motors lack the necessary depth and detail on induction machines.The Induction Machine Handbook fills industry's long-standing need for a comprehensive treatise embracing the many intricate facets of induction machine analysis and design. Moving gradually from simple to complex and from standard to

  3. Comprehensive Technical Report, General Electric Direct-Air-Cycle Aircraft Nuclear Propulsion Program, Program Summary and References

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, G.; Rothstein, A.J.

    1962-06-28

    This is one of twenty-one volumes sumarizing the Aircraft Nuclear Propulsion Program of the General Electric Company. This volume discusses the background to the General Electric program, and summarizes the various direct-air-cycle nuclear test assemblies and power plants that were developed. Because of the requirements of high performance, low weight, and small size, vast improvements in existing technology were required to meet the flight objectives. The technological progress achieved during the program is also summarized. The last appendix contains a compilation of the abstracts, tables of contents, and reference lists of the other twenty volumes.

  4. 依据标准探讨机床电气回路保护技术及其运用%Protection Technology of Machine Electrical Circuit and Its Practical Applications Based on the Relevant In-dustry Standards

    Institute of Scientific and Technical Information of China (English)

    孙伟; 马永青

    2015-01-01

    Machine tools' electrical design , installation and usage are related to the electrical circuit choosing , the specifications specify-ing of cables and circuit breaker and the technical conditions of electri-cal components etc . When the machine appears electrically abnormal or operating failure , the main work is speculating the failure through ana-lyzing the protection technology of electrical circuit . This paper is to explore the protection technology of machine tools' electrical circuit and its practical applications based on the relevant national and corporate industry standards .%机床的电气设计、安装与使用一定会涉及到电气回路的选择、电缆及断路器的规格指定、电气元器件的技术条件等等.而当机床出现电气装置异常或运转失效时,也会以分析电气回路的保护技术为主来推测故障.本文依据相关的国家及企业行业标准来探讨机床电气回路的保护技术和应用.

  5. Standard technical specifications General Electric plants, BWR/6. Volume 1, Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    This report documents the results of the combined effort of the NRC and the industry to produce improved Standard Technical Specifications (STS), Revision 1 for General Electric BWR/6 Plants. The changes reflected in Revision 1 resulted from the experience gained from license amendment applications to convert to these improved STS or to adopt partial improvements to existing technical specifications. This NUREG is the result of extensive public technical meetings and discussions between the Nuclear Regulatory Commission (NRC) staff and various nuclear power plant licensees, Nuclear Steam Supply System (NSSS) Owners Groups, NSSS vendors, and the Nuclear Energy Institute (NEI). The improved STS were developed based on the criteria in the Final Commission Policy Statement on Technical Specifications Improvements for Nuclear Power Reactors, dated July 22, 1993. The improved STS will be used as the basis for individual nuclear power plant licensees to develop improved plant-specific technical specifications. This report contains three volumes. Volume 1 contains the Specifications for all chapters and sections of the improved STS. Volume 2 contains the Bases for Chapters 2.0 and 3.0, and Sections 3.1--3.3 of the improved STS. Volume 3 contains the Bases for Sections 3.4--3.10 of the improved STS.

  6. Aging assessment of Westinghouse PWR and General Electric BWR containment isolation functions

    Energy Technology Data Exchange (ETDEWEB)

    Lee, B.S.; Travis, R.; Grove, E.; DiBiasio, A.

    1996-03-01

    A study was performed to assess the effects of aging on the Containment Isolation (CI) functions of Westinghouse Pressurized Water Reactors and General Electric Boiling Water Reactors. This study is part of the Nuclear Plant Aging Research (NPAR) program, sponsored by the U.S. Nuclear Regulatory Commission. The objectives of this program are to provide an understanding of the aging process and how it affects plant safety so that it can be properly managed. This is one of a number of studies performed under the NPAR program which provide a technical basis for the identification and evaluation of degradation caused by age. Failure data from two national databases, Nuclear Plant Reliability Data System (NPRDS) and Licensee Event Reports (LERs), as well as plant specific data were reviewed and analyzed to understand the effects of aging on the CI functions. This study provided information on the effects of aging on component failure frequency, failure modes, and failure causes. Current inspection, surveillance, and monitoring practices were also reviewed.

  7. Seismic risk analysis for General Electric Plutonium Facility, Pleasanton, California. Final report, part II

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-27

    This report is the second of a two part study addressing the seismic risk or hazard of the special nuclear materials (SNM) facility of the General Electric Vallecitos Nuclear Center at Pleasanton, California. The Part I companion to this report, dated July 31, 1978, presented the seismic hazard at the site that resulted from exposure to earthquakes on the Calaveras, Hayward, San Andreas and, additionally, from smaller unassociated earthquakes that could not be attributed to these specific faults. However, while this study was in progress, certain additional geologic information became available that could be interpreted in terms of the existance of a nearby fault. Although substantial geologic investigations were subsequently deployed, the existance of this postulated fault, called the Verona Fault, remained very controversial. The purpose of the Part II study was to assume the existance of such a capable fault and, under this assumption, to examine the loads that the fault could impose on the SNM facility. This report first reviews the geologic setting with a focus on specifying sufficient geologic parameters to characterize the postulated fault. The report next presents the methodology used to calculate the vibratory ground motion hazard. Because of the complexity of the fault geometry, a slightly different methodology is used here compared to the Part I report. This section ends with the results of the calculation applied to the SNM facility. Finally, the report presents the methodology and results of the rupture hazard calculation.

  8. The NASA Environmentally Responsible Aviation Project/General Electric Open Rotor Test Campaign

    Science.gov (United States)

    Van Zante, Dale

    2013-01-01

    The Open Rotor is a modern version of the UnDucted Fan (UDF) that was flight tested in the late 1980's through a partnership between NASA and General Electric (GE). Tests were conducted in the 9'x15' Low Speed Wind Tunnel and the 8'x6' Supersonic Wind Tunnel starting in late 2009 and completed in early 2012. Aerodynamic and acoustic data were obtained for takeoff, approach and cruise simulations. GE was the primary partner, but other organizations were involved such as Boeing and Airbus who provided additional hardware for fuselage simulations. This test campaign provided the acoustic and performance characteristics for modern open rotor blades designs." NASA and GE conducted joint systems analysis to evaluate how well new blade designs would perform on a B737 class aircraft, and compared the results to an advanced higher bypass ratio turbofan." Acoustic shielding experiments were performed at NASA GRC and Boeing LSAF facilities to provide data for noise estimates of unconventional aircraft configurations with Open Rotor propulsion systems." The work was sponsored by NASA's aeronautics programs, including the Subsonic Fixed Wing (SFW) and the Environmentally Responsible Aviation (ERA) projects."

  9. General Electric Company Hanford Works, Project C-431-A Production Facility-Section A, design report

    Energy Technology Data Exchange (ETDEWEB)

    Colburn, R.T.

    1951-03-29

    The 100-C project is to be located adjacent to the present 100-B Area. It is planned to build an addition to the present 181-B river pump house using the same elevations for pump settings, intakes, and floors as for the present pump house, thus maintaining the same suction conditions and flood protection as B Area. The 105 Building will be located on higher ground than B Area and therefore, protection against possible flood damage is assured. This report is divided into the following sections: (1) general description of project; (2) addition to existing river pump house; (3) raw water lines from 181-B addition to 183-C lead house; (4) the 183-C filter plant; (5) 190-C process pump house; (6) power house addition; (7) high tanks; (8) retention basins; (9) outside streamlines; (10) primary substation; (11) outside underground lines; (12) outside electric lines; (13) roads, railroads, walks, fences; (14) structural design of all buildings; and (15) architectural design of all buildings.

  10. Determination of efficiencies, loss mechanisms, and performance degradation factors in chopper controlled dc vehical motors. Section 2: The time dependent finite element modeling of the electromagnetic field in electrical machines: Methods and applications. Ph.D. Thesis

    Science.gov (United States)

    Hamilton, H. B.; Strangas, E.

    1980-01-01

    The time dependent solution of the magnetic field is introduced as a method for accounting for the variation, in time, of the machine parameters in predicting and analyzing the performance of the electrical machines. The method of time dependent finite element was used in combination with an also time dependent construction of a grid for the air gap region. The Maxwell stress tensor was used to calculate the airgap torque from the magnetic vector potential distribution. Incremental inductances were defined and calculated as functions of time, depending on eddy currents and saturation. The currents in all the machine circuits were calculated in the time domain based on these inductances, which were continuously updated. The method was applied to a chopper controlled DC series motor used for electric vehicle drive, and to a salient pole sychronous motor with damper bars. Simulation results were compared to experimentally obtained ones.

  11. Multi-objective component sizing of a power-split plug-in hybrid electric vehicle powertrain using Pareto-based natural optimization machines

    Science.gov (United States)

    Mozaffari, Ahmad; Vajedi, Mahyar; Chehresaz, Maryyeh; Azad, Nasser L.

    2016-03-01

    The urgent need to meet increasingly tight environmental regulations and new fuel economy requirements has motivated system science researchers and automotive engineers to take advantage of emerging computational techniques to further advance hybrid electric vehicle and plug-in hybrid electric vehicle (PHEV) designs. In particular, research has focused on vehicle powertrain system design optimization, to reduce the fuel consumption and total energy cost while improving the vehicle's driving performance. In this work, two different natural optimization machines, namely the synchronous self-learning Pareto strategy and the elitism non-dominated sorting genetic algorithm, are implemented for component sizing of a specific power-split PHEV platform with a Toyota plug-in Prius as the baseline vehicle. To do this, a high-fidelity model of the Toyota plug-in Prius is employed for the numerical experiments using the Autonomie simulation software. Based on the simulation results, it is demonstrated that Pareto-based algorithms can successfully optimize the design parameters of the vehicle powertrain.

  12. Design of Static Electricity Mist Spray Method of Machine-harvested Cotton%一种机采棉静电喷雾方式的设计

    Institute of Scientific and Technical Information of China (English)

    葛云; 张立新; 魏敏; 金军民

    2014-01-01

    The paper was put forward a kind of inductive static electricity mist spray method of machine-harvested cotton, setting sensing electrode at the pump outlet, charging liquid medicine when entering the spray hose and then atomizing jet by the nozzle. Adsorption cotton plant which carry positive electricity under the influence of auxiliary fan air, which has the characteristics of simple structure and convenient maintenance.%提出一种机采棉感应式静电喷雾方式,即在药液泵出水口处设置感应电极,对从药箱泵出的药液在进入喷雾胶管时充电,然后由喷头雾化喷出。在风机辅助气流作用下吸附在带正电荷的棉株上,具有相对结构简单、维修方便的特点。

  13. When Machines Design Machines!

    DEFF Research Database (Denmark)

    2011-01-01

    Until recently we were the sole designers, alone in the driving seat making all the decisions. But, we have created a world of complexity way beyond human ability to understand, control, and govern. Machines now do more trades than humans on stock markets, they control our power, water, gas...... and food supplies, manage our elevators, microclimates, automobiles and transport systems, and manufacture almost everything. It should come as no surprise that machines are now designing machines. The chips that power our computers and mobile phones, the robots and commercial processing plants on which we...... depend, all are now largely designed by machines. So what of us - will be totally usurped, or are we looking at a new symbiosis with human and artificial intelligences combined to realise the best outcomes possible. In most respects we have no choice! Human abilities alone cannot solve any of the major...

  14. Comprehensive Technical Report, General Electric Direct-Air-Cycle Aircraft Nuclear Propulsion Program; Aircraft Nuclear Propulsion Application Studies

    Energy Technology Data Exchange (ETDEWEB)

    Comassar, S.

    1962-04-30

    This volume is one of twenty-one summarizing the Aircraft Nuclear Propulsion Program of the General Electric Company. This portion describes the studies of advanced applications of nuclear reactors that were performed, including various types of aircraft, missiles, space vehicles, ships, and portable power plants.

  15. 76 FR 27669 - Penske Logistics LLC, a Subsidiary of General Electric/Penske Corporation Including On-Site...

    Science.gov (United States)

    2011-05-12

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration Penske Logistics LLC, a Subsidiary of General Electric/Penske... Regarding Application for Reconsideration applicable to workers and former workers of Penske Logistics LLC...

  16. 77 FR 14838 - General Electric-Hitachi Global Laser Enrichment LLC, Commercial Laser-Based Uranium Enrichment...

    Science.gov (United States)

    2012-03-13

    ... COMMISSION General Electric-Hitachi Global Laser Enrichment LLC, Commercial Laser-Based Uranium Enrichment... applicant) to authorize construction of a laser-based uranium enrichment facility and possession and use of...-based uranium enrichment facility. Revisions to the application were submitted on March 23, 2010;...

  17. 77 FR 13367 - General Electric-Hitachi Global Laser Enrichment, LLC, Proposed Laser-Based Uranium Enrichment...

    Science.gov (United States)

    2012-03-06

    ... COMMISSION General Electric-Hitachi Global Laser Enrichment, LLC, Proposed Laser-Based Uranium Enrichment...- Hitachi Global Laser Enrichment, LLC (GLE) Uranium Enrichment Facility. On June 26, 2009, GLE submitted a... uranium enrichment facility (the ``proposed action''). The GLE proposes to locate the facility on...

  18. Comprehensive Technical Report, General Electric Direct-Air-Cycle Aircraft Nuclear Propulsion Program; Aircraft Nuclear Propulsion Application Studies

    Energy Technology Data Exchange (ETDEWEB)

    Comassar, S.

    1962-04-30

    This volume is one of twenty-one summarizing the Aircraft Nuclear Propulsion Program of the General Electric Company. This portion describes the studies of advanced applications of nuclear reactors that were performed, including various types of aircraft, missiles, space vehicles, ships, and portable power plants.

  19. A discrete time model of a power conditioner fed permanent magnet brushless dc motor system for aerospace and electric vehicle applications for design purpose using finite elements for machine parameter determination

    Science.gov (United States)

    Nehl, T. W.

    1980-12-01

    A discrete state space model of a power conditioner fed permanent magnet brushless dc motor for aerospace and electric vehicle applications is developed. The parameters which describe that machine portion of this model are derived from a two dimensional nonlinear magnetic field analysis using the finite element method. The model predicts the instantaneous mechanical and electrical behavior of a prototype electromechanical actuator for possible use on board the shuttle orbiter. The model is also used to simulate the instantaneous performance of an advanced electric vehicle propulsion unit. The results of the computer simulations are compared with experimental test data and excellent agreement between the two is found in all cases.

  20. General Electric PETtrace cyclotron as a neutron source for boron neutron capture therapy

    Science.gov (United States)

    Bosko, Andrey

    This research investigates the use of a PETtrace cyclotron produced by General Electric (GE) as a neutron source for boron neutron capture therapy (BNCT). The GE PETtrace was chosen for this investigation because this type of cyclotron is popular among nuclear pharmacies and clinics in many countries; it is compact and reliable; it produces protons with energies high enough to produce neutrons with appropriate energy and fluence rate for BNCT and it does not require significant changes in design to provide neutrons. In particular, the standard PETtrace 18O target is considered. The cyclotron efficiency may be significantly increased if unused neutrons produced during radioisotopes production could be utilized for other medical modalities such as BNCT at the same time. The resulting dose from the radiation emitted from the target is evaluated using the Monte Carlo radiation transport code MCNP at several depths in a brain phantom for different scattering geometries. Four different moderating materials of various thicknesses were considered: light water, carbon, heavy water, arid Fluental(TM). The fluence rate tally was used to calculate photon and neutron dose, by applying fluence rate-to-dose conversion factors. Fifteen different geometries were considered and a 30-cm thick heavy water moderator was chosen as the most suitable for BNCT with the GE PETtrace cyclotron. According to the Brookhaven Medical Research Reactor (BMRR) protocol, the maximum dose to the normal brain is set to 12.5 RBEGy, which for the conditions of using a heavy water moderator, assuming a 60 muA beam current, would be reached with a treatment time of 258 min. Results showed that using a PETtrace cyclotron in this configuration provides a therapeutic ratio of about 2.4 for depths up to 4 cm inside a brain phantom. Further increase of beam current proposed by GE should significantly improve the beam quality or the treatment time and allow treating tumors at greater depths.

  1. Radioactive waste shipments to Hanford Retrievable Storage from the General Electric Vallecitos Nuclear Center, Pleasanton, California

    Energy Technology Data Exchange (ETDEWEB)

    Vejvoda, E.J.; Pottmeyer, J.A.; DeLorenzo, D.S.; Weyns-Rollosson, M.I. [Los Alamos Technical Associates, Inc., NM (United States); Duncan, D.R. [Westinghouse Hanford Co., Richland, WA (United States)

    1993-10-01

    During the next two decades the transuranic (TRU) wastes now stored in the burial trenches and storage facilities at the Hanford Site are to be retrieved, processed at the Waste Receiving and Processing Facility, and shipped to the Waste Isolation Pilot Plant near Carlsbad, New Mexico for final disposal. Approximately 3.8% of the TRU waste to be retrieved for shipment to WIPP was generated at the General Electric (GE) Vallecitos Nuclear Center (VNC) in Pleasanton, California and shipped to the Hanford Site for storage. The purpose of this report is to characterize these radioactive solid wastes using process knowledge, existing records, and oral history interviews. The waste was generated almost exclusively from the activities, of the Plutonium Fuels Development Laboratory and the Plutonium Analytical Laboratory. Section 2.0 provides further details of the VNC physical plant, facility operations, facility history, and current status. The solid radioactive wastes were associated with two US Atomic Energy Commission/US Department of Energy reactor programs -- the Fast Ceramic Reactor (FCR) program, and the Fast Flux Test Reactor (FFTR) program. These programs involved the fabrication and testing of fuel assemblies that utilized plutonium in an oxide form. The types and estimated quantities of waste resulting from these programs are discussed in detail in Section 3.0. A detailed discussion of the packaging and handling procedures used for the VNC radioactive wastes shipped to the Hanford Site is provided in Section 4.0. Section 5.0 provides an in-depth look at this waste including the following: weight and volume of the waste, container types and numbers, physical description of the waste, radiological components, hazardous constituents, and current storage/disposal locations.

  2. Electric Control System Grounding Analysis of Railway Heavy Duty Track Maintenance Machine%铁路大型养路机械电气控制系统接地分析

    Institute of Scientific and Technical Information of China (English)

    程连飞

    2011-01-01

    分析了铁路大型养路机械电气系统的接地方式,阐述了因接地不当对电气控制系统造成的影响,并提出了改进措施.合理的接地能够改善大型养路机械的作业精度,并提高电气控制系统的可靠性和稳定性.%Grounding styles of electric system for the railway heavy duty tracl maintenance machine were analyzed,and impac due to improper grounding as well as improving mesaures of electric control system was described.It was proved that resonable grounding can improve operation accuracy of the railway heavy duty track maintenance machine and the reliability and stability of the electric control system.

  3. A general procedure to generate models for urban environmental-noise pollution using feature selection and machine learning methods.

    Science.gov (United States)

    Torija, Antonio J; Ruiz, Diego P

    2015-02-01

    The prediction of environmental noise in urban environments requires the solution of a complex and non-linear problem, since there are complex relationships among the multitude of variables involved in the characterization and modelling of environmental noise and environmental-noise magnitudes. Moreover, the inclusion of the great spatial heterogeneity characteristic of urban environments seems to be essential in order to achieve an accurate environmental-noise prediction in cities. This problem is addressed in this paper, where a procedure based on feature-selection techniques and machine-learning regression methods is proposed and applied to this environmental problem. Three machine-learning regression methods, which are considered very robust in solving non-linear problems, are used to estimate the energy-equivalent sound-pressure level descriptor (LAeq). These three methods are: (i) multilayer perceptron (MLP), (ii) sequential minimal optimisation (SMO), and (iii) Gaussian processes for regression (GPR). In addition, because of the high number of input variables involved in environmental-noise modelling and estimation in urban environments, which make LAeq prediction models quite complex and costly in terms of time and resources for application to real situations, three different techniques are used to approach feature selection or data reduction. The feature-selection techniques used are: (i) correlation-based feature-subset selection (CFS), (ii) wrapper for feature-subset selection (WFS), and the data reduction technique is principal-component analysis (PCA). The subsequent analysis leads to a proposal of different schemes, depending on the needs regarding data collection and accuracy. The use of WFS as the feature-selection technique with the implementation of SMO or GPR as regression algorithm provides the best LAeq estimation (R(2)=0.94 and mean absolute error (MAE)=1.14-1.16 dB(A)). Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Investigation of a Novel Mechanical to Thermal Energy Converter Based on the Inverse Problem of Electric Machines

    Directory of Open Access Journals (Sweden)

    Lei Chen

    2016-07-01

    Full Text Available A novel converter that can directly transform electrical, wind, hydraulic and other types of mechanical energy into thermal energy is presented in this study. First, the thermal energy of the converter is classified and then calculated by a finite element method. The eddy current distribution in the stator of the converter is also discussed. Second, the temperature field of the converter is calculated using a boundary element method. Subsequently, a thermal power–temperature coupled calculation method is presented to calculate the actual thermal power and temperature of the converter. The characteristic curves of the actual thermal power and the increase in water flow temperature are then presented based on the calculation results. Lastly, an experimental system is built, the thermal power and temperature of the converter are measured and the experimental results and the analytical calculations are compared.

  5. General classical and quantum-mechanical description of magnetic resonance: an application to electric-dipole-moment experiments

    Energy Technology Data Exchange (ETDEWEB)

    Silenko, Alexander J. [Belarusian State University, Research Institute for Nuclear Problems, Minsk (Belarus); Joint Institute for Nuclear Research, Bogoliubov Laboratory of Theoretical Physics, Dubna (Russian Federation)

    2017-05-15

    A general theoretical description of a magnetic resonance is presented. This description is necessary for a detailed analysis of spin dynamics in electric-dipole-moment experiments in storage rings. General formulas describing a behavior of all components of the polarization vector at the magnetic resonance are obtained for an arbitrary initial polarization. These formulas are exact on condition that the nonresonance rotating field is neglected. The spin dynamics is also calculated at frequencies far from resonance with allowance for both rotating fields. A general quantum-mechanical analysis of the spin evolution at the magnetic resonance is fulfilled and the full agreement between the classical and quantum-mechanical approaches is shown. Quasimagnetic resonances for particles and nuclei moving in noncontinuous perturbing fields of accelerators and storage rings are considered. Distinguishing features of quasimagnetic resonances in storage ring electric-dipole-moment experiments are investigated in detail. The exact formulas for the effect caused by the electric dipole moment are derived. The difference between the resonance effects conditioned by the rf electric-field flipper and the rf Wien filter is found and is calculated for the first time. The existence of this difference is crucial for the establishment of a consent between analytical derivations and computer simulations and for checking spin tracking programs. The main systematical errors are considered. (orig.)

  6. Time horizons and electricity futures: An application of Nicholas Georgescu-Roegen's general theory of economic production

    Energy Technology Data Exchange (ETDEWEB)

    Farrell, Katharine N. [Department of Economics, Helmholtz Centre for Environmental Research - UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Gibson Institute for Land, Food and Environment, Queen' s University of Belfast, Northern Ireland (United Kingdom); Mayumi, Kozo [Faculty of Integrated Arts and Sciences, The University of Tokushima (Japan)

    2009-03-15

    This paper reports theoretical economic production work and uses electricity futures trading to illustrate its argument. The focus is relationships between time, production and tradition both in Nicholas Georgescu-Roegen's analytical representation of the production process (i.e., flow/fund model) and in his dialectical scheme dealing with the evolutionary changes in the economic process. Our main arguments are (1) the flow/fund model is designed to be employed in conjunction with attention to how the boundaries of a given process are determined and (2) process boundaries are dialectical distinctions - between process and not-process - that are strongly related to time and tradition. We propose that Georgescu-Roegen's The Entropy Law and the Economic Process is best understood as the elaboration of a general theory of economic production and we developed two conceptual tools (time {open_square} and meta-funds), both of which are related to the dialectical distinction between process and not-process, which we use to operationalise this general theory. Finally, we demonstrate that, although trading in electricity futures is surprising if one uses a stock/flow vs services distinction (because electricity supply is classed as a service) it appears perfectly logical under Georgescu-Roegen's general theory: shortening time horizons, combined with a shift in the relationship between raw fuel supplies and power production procedures, lead to a shift in the status of electricity supply, from fund to flow. (author)

  7. 数控机床伺服驱动系统齿轮配比设计%Matching design for electrical gear of servo driving system of CNC machine tool

    Institute of Scientific and Technical Information of China (English)

    李茂胜

    2012-01-01

    在数控车床改造中,机床进给伺服驱动系统是重要的组成部分,控制精度是非常重要的指标.该文介绍了数控机床进给伺服系统的组成和分类,同时介绍了电子齿轮在数控机床中的应用情况,介绍了电子齿轮的概念,以配置了安川伺服电机和驱动器的数控进给系统为例,介绍了电子齿轮比的计算过程.%Servo feeding system is a part of CNC machine tool,which control precision is a very important index in upgrading CNC machine tool.The composition and assortment of servo feeding system of the CNC machine tool is illustrated as well as the application of electric gear in CNC machine tool and the concept of electric gear.By taking the CNC feeding system with Anchuan servo motor and driver as an example,the calculating process for proportion of electrical gear is introduced in detail.

  8. Pattern recognition & machine learning

    CERN Document Server

    Anzai, Y

    1992-01-01

    This is the first text to provide a unified and self-contained introduction to visual pattern recognition and machine learning. It is useful as a general introduction to artifical intelligence and knowledge engineering, and no previous knowledge of pattern recognition or machine learning is necessary. Basic for various pattern recognition and machine learning methods. Translated from Japanese, the book also features chapter exercises, keywords, and summaries.

  9. Magnetic equivalent circuit model for unipolar hybrid excitation synchronous machine

    Directory of Open Access Journals (Sweden)

    Kupiec Emil

    2015-03-01

    Full Text Available Lately, there has been increased interest in hybrid excitation electrical machines. Hybrid excitation is a construction that combines permanent magnet excitation with wound field excitation. Within the general classification, these machines can be classified as modified synchronous machines or inductor machines. These machines may be applied as motors and generators. The complexity of electromagnetic phenomena which occur as a result of coupling of magnetic fluxes of separate excitation systems with perpendicular magnetic axis is a motivation to formulate various mathematical models of these machines. The presented paper discusses the construction of a unipolar hybrid excitation synchronous machine. The magnetic equivalent circuit model including nonlinear magnetization curves is presented. Based on this model, it is possible to determine the multi-parameter relationships between the induced voltage and magnetomotive force in the excitation winding. Particular attention has been paid to the analysis of the impact of additional stator and rotor yokes on above relationship. Induced voltage determines the remaining operating parameters of the machine, both in the motor and generator mode of operation. The analysis of chosen correlations results in an identification of the effective control range of electromotive force of the machine.

  10. Peeling-and-Coring-Machine Operator 529.886 -- Technical Report on Standardization of the General Aptitude Test Battery.

    Science.gov (United States)

    Manpower Administration (DOL), Washington, DC. U.S. Training and Employment Service.

    The United States Training and Employment Service General Aptitude Test Battery (GATB), first published in 1947, has been included in a continuing program of research to validate the tests against success in many different occupations. The GATB consists of 12 tests which measure nine aptitudes: General Learning Ability; Verbal Aptitude; Numerical…

  11. A generalized energy model for the behavior of single-crystal magneto-electric composites

    Science.gov (United States)

    Atulasimha, Jayasimha; Akhras, George; Flatau, Alison B.

    2007-04-01

    This paper explores a unified energy-based approach to model the non-linear behavior of both magnetostrictive and piezoelectric materials. While the energy-approach developed by Armstrong has been shown to capture the magnetostrictive behavior of materials such as Terfenol-D1 and Iron-Gallium2 along different crystallographic directions, extending this approach to piezoelectric materials presents a considerable challenge. Some piezo-electric materials such as PMN-PT and BaTiO 3 may undergo phase changes under applied electric fields and stress in addition to polarization switching. A modeling approach is developed in this paper to capture these effects. Finally, it is shown that the constitutive behavior for the piezo-electric/magnetostrictive layers, coupled by a simple blocked-force approach, is likely to model the behavior of magneto-electric composites.

  12. Numerical-Analytical Method for Magnetic Field Computation in Rotational Electric Machines%旋转电机磁场计算的数值解析结合法

    Institute of Scientific and Technical Information of China (English)

    章跃进; 江建中; 屠关镇

    2003-01-01

    A numerical-analytical method is applied for the two-dimensional magnetic field computation in rotational electric machines in this paper. The analytical expressions for air gap magnetic field are derived. The pole pairs in the expressions are taken into account so that the solution region can be reduced within one periodic range. The numerical and analytical magnetic field equations are linked with equal vector magnetic potential boundary conditions. The magnetic field of a brushless permanent magnet machine is computed by the proposed method. The result is compared to that obtained by finite element method so as to validate the correction of the method.

  13. Design and Realization of The machine electricity calculator intelligence data collects%机电计算机智能数据采集模块的设计与实现

    Institute of Scientific and Technical Information of China (English)

    曹兴冈

    2016-01-01

    随着综合化、模块化航空电子系统发展,机电系统向着集成化、数字化、系统信息共享与综合化的方向发展,智能数据采集是其中重要的采集单元,文中介绍了智能数据采集模块的系统结构、模拟离散接口设计、双通道设计及软件结构等,采用模块化、标准化思想,其通用性和推广性极强。%Along with synthesize to turn,the mold piece turn the aviation electronics system development, the electricity & machine system facing integration turn,the numeral turn,the system information share with synthesize to turn of direction development, the intelligence data's collect is to collect unit importantly among them, introducing the intelligence data to collect the system structure of the mold piece and imitating in the text long-lost connect a people's design,double passage design and the software structure etc, adopt the mold piece to turn,standardize thought, its in general use and expand very strong..

  14. Research of Relationship Between Interelectrode Dielectric Properties and Energy Distribution in Wire Electrical Discharge Machining%电火花线切割极问介电特性与放电能量分配关系

    Institute of Scientific and Technical Information of China (English)

    刘志东; 魏为; 陆霖琰; 徐安阳

    2012-01-01

    建立了电火花线切割极间介质电阻模型,分析了加工能量与极间介质电导率、工件厚度之间的关系,并对极间介质电阻模型进行了实验验证.研究结果表明,随着电导率的升高或者工件厚度的增加,放电期间极间“漏电流”增大,损耗在极间介质的能量增加,加工效率降低,电导率变化导致的极间电阻改变对于加工效率的影响显著.%A resistance model of (WEDM) was established. And interelectrode dielectric fluid in wire electrical discharge machining the relationship among machining energy, electrical conductivity and thickness of a workpiece was analyzed. The resistance model of interelectrode dielectric fluid was verified by experiments. The results show that with the higher electrical conductivity or the thickness of work- piece, the larger the interelectrode leakage current is during discharge, the more the energy loss in the in- terelectrode dielectric fluid, the lower the machining efficiency. Cutting efficiency is obviously influenced by the change of the resistance which is due to the change of electrical conductivity.

  15. Manufacturing cost analysis of a parabolic dish concentrator (General Electric design) for solar thermal electric power systems in selected production volumes

    Science.gov (United States)

    1981-01-01

    The manufacturing cost of a General Electric 12 meter diameter concentrator was estimated. This parabolic dish concentrator for solar thermal system was costed in annual production volumes of 100 - 1,000 - 5,000 - 10,000 - 50,000 100,000 - 400,000 and 1,000,000 units. Presented for each volume are the costs of direct labor, material, burden, tooling, capital equipment and buildings. Also presented is the direct labor personnel and factory space requirements. All costs are based on early 1981 economics.

  16. A feasibility study of full-bridge type superconducting fault current controller on electric machine power stability

    Science.gov (United States)

    Jang, J. Y.; Hwang, Y. J.; Lee, J.; Ko, T. K.

    2016-02-01

    Recently, because of the advent of Smart Grid and integration of distributed generations, electrical power grids are facing uncountable challenges. Increase of fault current is one of such serious challenges and there are some fault current limiters (FCLs) that can limit the fault current. Existing grid protection FCLs, however, simply limit the fault current passively and can allow the existing protection coordination schemes to fail. This phenomenon leads to catastrophic failure in the complex system and may cause unpredictable power grid operation. Unlike a FCL, a superconducting fault current controller (SFCC) employs a full-bridge thyristor rectifier, a high temperature superconducting (HTS) DC reactor, and an embedded control unit to maintain the fault current level at a proper value by adjusting the phase angle of thyristors. This paper contains experimental and numerical analysis to design and fabricate a SFCC system for protection and stability improvement in power grids. At first, fundamental characteristics of a SFCC system were introduced. System circuit diagram and operational principles were proposed. Secondly, the developed small-scale SFCC system was introduced and verified. A 40 Vrms/30 Arms class prototype SFCC employing HTS DC reactor was fabricated and short circuit tests that simulate various fault conditions were implemented to verify the control performance of the fault current. Finally, the practical feasibility of application of the SFCC system to the power system was studied. The problems caused by three-phase faults from the power grid were surveyed and transient stability analysis of the power system was conducted by simulations. From the experimental and simulation results, we can verify the feasibility of the SFCC in power system.

  17. Optimization of process parameters for electrical discharge machining%电火花加工工艺电参数的优化

    Institute of Scientific and Technical Information of China (English)

    郭晓霞

    2013-01-01

    以Cr12MoV为工件材料,研究电火花加工中脉冲宽度、脉冲间隔和放电电流等工艺参数对工艺指标材料去除率、电极损耗率和表面粗糙度的影响。为了优化工艺指标,将相关分析方法与Taguchi方法相结合,通过灰相关度系数值决定优化的工艺参数,最后利用方差分析,确定放电电流对工艺指标的最大影响。%Electrical discharge machining of Cr 12MoV is studied.Influence of pulse-on time,pulse-off time and discharge current are investigated for material removal rate and electrode wear ratio and surface roughness .In order to optimization process respon-ses,the grey relational analysis based Taguchi method is used .The grey relational grade is used to determine the optimal process parameters .Analysis of variance shows that discharge current is the most significant parameter for process reponses .

  18. Effects of airborne-particle abrasion, sodium hydroxide anodization, and electrical discharge machining on porcelain adherence to cast commercially pure titanium.

    Science.gov (United States)

    Acar, Asli; Inan, Ozgür; Halkaci, Selçuk

    2007-07-01

    The aim of this study was to determine the effect of airborne-particle abrasion (APA), sodium hydroxide anodization (SHA), and electrical discharge machining (EDM) on cast titanium surfaces and titanium-porcelain adhesion. Ninety titanium specimens were cast with pure titanium and the alpha-case layer was removed. Specimens were randomly divided into three groups. Ten specimens from each group were subjected to APA. SHA was applied to the second subgroups, and the remaining specimens were subjected to the EDM. For the control group, 10 specimens were cast using NiCr alloy and subjected to only APA. Surfaces were examined by using scanning electron microscope and a surface profilometer. Three titanium porcelains were fused on the titanium surfaces, whereas NiCr specimens were covered with conventional porcelain. Titanium-porcelain adhesion was characterized by a 3-point bending test. Statistical analysis showed that the porcelain-metal bond strength of the control group was higher than that of the titanium-porcelain system (p < 0.05). There were no significant differences between the bond strengths of titanium groups (p 0.05), except the bond strengths of Noritake Super Porcelain TI-22 groups on which APA and SHA were applied (p < 0.05). SHA and EDM as surface treatment did not improve titanium-porcelain adhesion when compared to APA.

  19. Chaotic Boltzmann machines.

    Science.gov (United States)

    Suzuki, Hideyuki; Imura, Jun-ichi; Horio, Yoshihiko; Aihara, Kazuyuki

    2013-01-01

    The chaotic Boltzmann machine proposed in this paper is a chaotic pseudo-billiard system that works as a Boltzmann machine. Chaotic Boltzmann machines are shown numerically to have computing abilities comparable to conventional (stochastic) Boltzmann machines. Since no randomness is required, efficient hardware implementation is expected. Moreover, the ferromagnetic phase transition of the Ising model is shown to be characterised by the largest Lyapunov exponent of the proposed system. In general, a method to relate probabilistic models to nonlinear dynamics by derandomising Gibbs sampling is presented.

  20. General Relationship between Field Electrical Resistivity Value (ERV and Basic Geotechnical Properties (BGP

    Directory of Open Access Journals (Sweden)

    Mohd Hazreek Zainal Abidin

    2014-09-01

    Full Text Available Electrical resistivity technique is a popular alternative method used in geotechnical soil investigations. Most past applications have been particularly in the area of subsurface ground investigations such as to locate boulder, bedrock, water table, etc. Traditionally, this method was performed by a geophysicist expert for data acquisition, processing and interpretation. The final outcome from the electrical resistivity technique was an anomaly image which used to describe and conclude the particular soil condition measured. The anomalies highlighted uncertainties on the nature of soil that was often variable and depended on each particular site condition that gave a site dependent soil electrical resistivity value (ERV. Hence, this study demonstrates a relationship between ERV (ρ and some of the basic geotechnical properties (BGP such as soil moisture content (w, grain size of geomaterial (CS or FS, density (ρbulk and ρdry, porosity (η, void ratio (e and Atterberg limit (AL. Different soil samples were collected and tested under field and laboratory conditions to determine basic geotechnical properties immediately after the field electrical resistivity method was performed. It was found that the electrical resistivity value was different for number of soils tested and was relatively subjective to variations in the geotechnical properties. In other words, electrical resistivity value was greatly influenced by the geotechnical properties as the ERV was higher due to the lower moisture content, void ratio and porosity with a higher value of soil density and vice versa. The relationship of ERV and BGP can be described by ρ α 1/w, ρ α CS, ρ α 1/FS, ρ α ρbulk/dry and ρ α 1/AL. Hence, it was shown that behaviour of ERV was significantly influenced by the variation of basic soil properties and thus applicable to support and enhance the conventional stand alone anomaly outcome which is traditionally used for interpretation purposes.