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Sample records for volumetric negative-refractive-index transmission-line

  1. A new class of negative refractive index transmission line

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    We propose a new class of negative refractive index transmission line in which ideal operational amplifiers are applied to form the periodically loaded negative-impedance-converted inductors and capacitors. The phase response of the new transmission line is opposite to that of a positive refractive index conventional transmission line. Unlike the existing negative refractive index transmission line, the new negative refractive index transmission line is non-dispersive and thus can lead to many novel applications such as designing new broadband devices.

  2. Science Letters: Lattice type transmission line of negative refractive index

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this letter, we introduce a novel passive transmission line of negative refractive index (i.e., left-handedness) based on identical symmetrical lattice type structures [thus called "lattice type transmission line" (LT-TL)]. The dispersion characteristic and the transmission response of the proposed LT-TL are analyzed. While all the other left-handed passive transmission lines are of high pass, the present passive left-handed transmission line is of low pass. Compared with a conventional transmission line, the LT-TL has a phase shift of 180° in the entire wide pass-band.

  3. Multi-band Microwave Antennas and Devices based on Generalized Negative-Refractive-Index Transmission Lines

    Science.gov (United States)

    Ryan, Colan Graeme Matthew

    Focused on the quad-band generalized negative-refractive-index transmission line (G-NRI-TL), this thesis presents a variety of novel printed G-NRI-TL multi-band microwave device and antenna prototypes. A dual-band coupled-line coupler, an all-pass G-NRI-TL bridged-T circuit, a dual-band metamaterial leaky-wave antenna, and a multi-band G-NRI-TL resonant antenna are all new developments resulting from this research. In addition, to continue the theme of multi-band components, negative-refractive-index transmission lines are used to create a dual-band circularly polarized transparent patch antenna and a two-element wideband decoupled meander antenna system. High coupling over two independently-specified frequency bands is the hallmark of the G-NRI-TL coupler: it is 0.35lambda0 long but achieves approximately -3 dB coupling over both bands with a maximum insertion loss of 1 dB. This represents greater design flexibility than conventional coupled-line couplers and less loss than subsequent G-NRI-TL couplers. The single-ended bridged-T G-NRI-TL offers a metamaterial unit cell with an all-pass magnitude response up to 8 GHz, while still preserving the quad-band phase response of the original circuit. It is shown how the all-pass response leads to wider bandwidths and improved matching in quad-band inverters, power dividers, and hybrid couplers. The dual-band metamaterial leaky-wave antenna presented here was the first to be reported in the literature, and it allows broadside radiation at both 2 GHz and 6 GHz without experiencing the broadside stopband common to conventional periodic antennas. Likewise, the G-NRI-TL resonant antenna is the first reported instance of such a device, achieving quad-band operation between 2.5 GHz and 5.6 GHz, with a minimum radiation efficiency of 80%. Negative-refractive-index transmission line loading is applied to two devices: an NRI-TL meander antenna achieves a measured 52% impedance bandwidth, while a square patch antenna incorporates

  4. Experimental and theoretical verification of focusing in a large, periodically loaded transmission line negative refractive index metamaterial.

    Science.gov (United States)

    Iyer, Ashwin; Kremer, Peter; Eleftheriades, George

    2003-04-07

    We have previously shown that a new class of Negative Refractive Index (NRI) metamaterials can be constructed by periodically loading a host transmission line medium with inductors and capacitors in a dual (high-pass) configuration. A small planar NRI lens interfaced with a Positive Refractive Index (PRI) parallel-plate waveguide recently succeeded in demonstrating focusing of cylindrical waves. In this paper, we present theoretical and experimental data describing the focusing and dispersion characteristics of a significantly improved device that exhibits minimal edge effects, a larger NRI region permitting precise extraction of dispersion data, and a PRI region consisting of a microstrip grid, over which the fields may be observed. The experimentally obtained dispersion data exhibits excellent agreement with the theory predicted by periodic analysis, and depicts an extremely broadband region from 960MHz to 2.5GHz over which the refractive index remains negative. At the frequency at which the theory predicts a relative refractive index of -1, the measured field distribution shows a focal spot with a maximum beam width under one-half of a guide wavelength. These results are compared with field distributions obtained through mathematical simulations based on the plane-wave expansion technique, and exhibit a qualitative correspondence. The success of this experiment attests to the repeatability of the original experiment and affirms the viability of the transmission line approach to the design of NRI metamaterials.

  5. Negative refractive index metamaterials

    Directory of Open Access Journals (Sweden)

    Willie J. Padilla

    2006-07-01

    Full Text Available Engineered materials composed of designed inclusions can exhibit exotic and unique electromagnetic properties not inherent in the individual constituent components. These artificially structured composites, known as metamaterials, have the potential to fill critical voids in the electromagnetic spectrum where material response is limited and enable the construction of novel devices. Recently, metamaterials that display negative refractive index – a property not found in any known naturally occurring material – have drawn significant scientific interest, underscoring the remarkable potential of metamaterials to facilitate new developments in electromagnetism.

  6. Metamaterials and Negative Refractive Index

    National Research Council Canada - National Science Library

    D. R. Smith; J. B. Pendry; M. C. K. Wiltshire

    2004-01-01

    .... Artificial magnetism and negative refractive index are two specific types of behavior that have been demonstrated over the past few years, illustrating the new physics and new applications possible...

  7. Negative refractive index in chiral metamaterials.

    Science.gov (United States)

    Zhang, Shuang; Park, Yong-Shik; Li, Jensen; Lu, Xinchao; Zhang, Weili; Zhang, Xiang

    2009-01-16

    We experimentally demonstrate a chiral metamaterial exhibiting negative refractive index at terahertz frequencies. The presence of strong chirality in the terahertz metamaterial lifts the degeneracy for the two circularly polarized waves and allows for the achievement of negative refractive index without requiring simultaneously negative permittivity and negative permeability. The realization of terahertz chiral negative index metamaterials offers opportunities for investigation of their novel electromagnetic properties, such as negative refraction and negative reflection, as well as important terahertz device applications.

  8. Uniform Refraction in Negative Refractive Index Materials

    CERN Document Server

    Gutierrez, Cristian E

    2015-01-01

    We study the problem of constructing an optical surface separating two homogeneous, isotropic media, one of which has a negative refractive index. In doing so, we develop a vector form of Snell's law, which is used to study surfaces possessing a certain uniform refraction property, both in the near and far field cases. In the near field problem, unlike the case when both materials have positive refractive index, we show that the resulting surfaces can be neither convex nor concave.

  9. Uniform refraction in negative refractive index materials.

    Science.gov (United States)

    Gutiérrez, Cristian E; Stachura, Eric

    2015-11-01

    We study the problem of constructing an optical surface separating two homogeneous, isotropic media, one of which has a negative refractive index. In doing so, we develop a vector form of Snell's law, which is used to study surfaces possessing a certain uniform refraction property, in both the near- and far-field cases. In the near-field problem, unlike the case when both materials have positive refractive indices, we show that the resulting surfaces can be neither convex nor concave.

  10. Finite checkerboards of dissipative negative refractive index.

    Science.gov (United States)

    Chakrabarti, Sangeeta; Ramakrishna, S Anantha; Guenneau, S

    2006-12-25

    The electromagnetic properties of finite checkerboards consisting of alternating rectangular cells of positive refractive index (epsilon= +1, micro= +1) and negative refractive index (epsilon= -1, micro= -1) have been investigated numerically. We show that the numerical calculations have to be carried out with very fine discretization to accurately model the highly singular behaviour of these checkerboards. Our solutions show that, within the accuracy of the numerical calculations, the focusing properties of these checkerboards are reasonably robust in the presence of moderate levels of dissipation. We also show that even small systems of checkerboards can display focussing effects to some extent.

  11. Telescope resolution using negative refractive index materials

    Science.gov (United States)

    May, Jack L.; Jennetti, Tony

    2004-02-01

    Concepts are presented for using negative refractive index (NRI) materials to design parabolic reflector telescopes and antennas with resolutions significantly better than the diffractions limit. The main question we are attempting to answer is can negative refractive material be used to improve performance of parabolic systems even when the signal or light source is far away and no evanescent fields are present when they arrive at the parabolic reflector. The main approach is to take advantage of any knowledge that we have to recreate the evanescent fields. Fields are then adapted to improve a performance measure such a sharper focus or antenna rejection of interference. A negative refraction index lens is placed between the conventional reflector and focal plane to shape the point spread function. To produce telescope resolutions that are better than the diffraction limit, evanescent fields created by the reflection off of the parabolic surface are amplified and modified to generate fields that sharpen the focus. A second approach use available knowledge of an emitting aperture to synthesize a field at a distance that matches as closely as possible the field of the emitting aperture. The yet unproven conclusion is that techniques can be developed that will improve antenna and telescopes resolution that is better than the diffraction limit.

  12. Microwave gain medium with negative refractive index.

    Science.gov (United States)

    Ye, Dexin; Chang, Kihun; Ran, Lixin; Xin, Hao

    2014-12-19

    Artificial effective media are attractive because of the fantastic applications they may enable, such as super lensing and electromagnetic invisibility. However, the inevitable loss due to their strongly dispersive nature is one of the fundamental challenges preventing such applications from becoming a reality. In this study, we demonstrate an effective gain medium based on negative resistance, to overcompensate the loss of a conventional passive metamaterial, meanwhile keeping its original negative-index property. Energy conservation-based theory, full-wave simulation and experimental measurement show that a fabricated sample consisting of conventional sub-wavelength building blocks with embedded microwave tunnel diodes exhibits a band-limited Lorentzian dispersion simultaneously with a negative refractive index and a net gain. Our work provides experimental evidence to the assertion that a stable net gain in negative-index gain medium is achievable, proposing a potential solution for the critical challenge current metamateiral technology faces in practical applications.

  13. Negative refractive index in coaxial plasmon waveguides.

    Science.gov (United States)

    de Waele, René; Burgos, Stanley P; Atwater, Harry A; Polman, Albert

    2010-06-07

    We theoretically show that coaxial waveguides composed of a metallic core, surrounded by a dielectric cylinder and clad by a metal outer layer exhibit negative refractive index modes over a broad spectral range in the visible. For narrow dielectric gaps (10 nm GaP embedded in Ag) a figure-of-merit of 18 can be achieved at lambda(0) = 460 nm. For larger dielectric gaps the negative index spectral range extends well below the surface plasmon resonance frequency. By fine-tuning the coaxial geometry the special case of n = -1 at a figure-of-merit of 5, or n = 0 for a decay length of 500 nm can be achieved.

  14. Microwave gain medium with negative refractive index

    Science.gov (United States)

    Ye, Dexin; Chang, Kihun; Ran, Lixin; Xin, Hao

    2014-12-01

    Artificial effective media are attractive because of the fantastic applications they may enable, such as super lensing and electromagnetic invisibility. However, the inevitable loss due to their strongly dispersive nature is one of the fundamental challenges preventing such applications from becoming a reality. In this study, we demonstrate an effective gain medium based on negative resistance, to overcompensate the loss of a conventional passive metamaterial, meanwhile keeping its original negative-index property. Energy conservation-based theory, full-wave simulation and experimental measurement show that a fabricated sample consisting of conventional sub-wavelength building blocks with embedded microwave tunnel diodes exhibits a band-limited Lorentzian dispersion simultaneously with a negative refractive index and a net gain. Our work provides experimental evidence to the assertion that a stable net gain in negative-index gain medium is achievable, proposing a potential solution for the critical challenge current metamateiral technology faces in practical applications.

  15. Negative Refractive Index in Optics of Metal-Dielectric Composites

    OpenAIRE

    Kildishev, A.V.; Cai, W; Chettiar, U K; Yuan, H.-K.; Sarychev, A. K.; Drachev, V. P.; Shalaev, V. M.

    2005-01-01

    Specially designed metal-dielectric composites can have a negative refractive index in the optical range. Specifically, it is shown that arrays of single and paired nanorods can provide such negative refraction. For pairs of metal rods, a negative refractive index has been observed at 1.5 micrometer. The inverted structure of paired voids in metal films may also exhibit a negative refractive index. A similar effect can be accomplished with metal strips in which the refractive index can reach ...

  16. Broadband negative refractive index obtained by plasmonic hybridization in metamaterials

    Science.gov (United States)

    Nguyen, Hien T.; Bui, Tung S.; Yan, Sen; Vandenbosch, Guy A. E.; Lievens, Peter; Vu, Lam D.; Janssens, Ewald

    2016-11-01

    We experimentally demonstrate a broadband negative refractive index (NRI) behavior in combined dimer and fishnet dimer metamaterials operating in the GHz frequency range. The observations can be well explained by a hybridization model and are in agreement with numerical modelling results. Hybridization of the magnetic resonances is obtained by reducing the distance between the layers in the dimer structures. A ratio of the double negative refractive index bandwidth to operational frequency of approximately 10% was achieved in the fishnet dimer. The applicable frequency range of the broadband NRI was shown to scale with the size of the structures from the microwave to the far infrared.

  17. W-band Pancharatnam half-wave plate based on negative refractive index metamaterials.

    Science.gov (United States)

    Mohamed, Imran; Pisano, Giampaolo; Ng, Ming Wah

    2014-04-01

    Electromagnetic metamaterials, made from arrangements of subwavelength-sized structures, can be used to manipulate radiation. Designing metamaterials that have a positive refractive index along one axis and a negative refractive index along the orthogonal axis can result in birefringences, Δn>1. The effect can be used to create wave plates with subwavelength thicknesses. Previous attempts at making wave plates in this way have resulted in very narrow usable bandwidths. In this paper, we use the Pancharatnam method to increase the usable bandwidth. A combination of finite element method and transmission line models was used to optimize the final design. Experimental results are compared with the modeled data.

  18. W-Band Pancharatnam Half Wave Plate Based on Negative Refractive Index Metamaterials

    CERN Document Server

    Mohamed, Imran; Ng, Ming Wah

    2014-01-01

    Electromagnetic metamaterials, made from arrangements of subwavelength sized structures, can be used to manipulate radiation. Designing metamaterials that have a positive refractive index along one axis and a negative refractive index along the orthogonal axis can result in birefringences, $\\Delta n>1$. The effect can be used to create wave plates with subwavelength thicknesses. Previous attempts at making wave plates in this way have resulted in very narrow usable bandwidths. In this paper, we use the Pancharatnam method to increase the usable bandwidth. A combination of Finite Element Method and Transmission Line models were used to optimise the final design. Experimental results are compared to the modelled data.

  19. Comment on "Negative refractive index in artificial metamaterials".

    Science.gov (United States)

    Kildishev, Alexander V; Drachev, Vladimir P; Chettiar, Uday K; Shalaev, Vladimir M; Werner, Douglas H; Kwon, Do-Hoon

    2007-06-01

    We dispute Grigorenko's statement [Opt. Lett. 31, 2483 (2006)] that measuring only the reflection intensity spectrum is sufficient for determining the effective refractive index. In addition, our simulations do not confirm his conclusions regarding the negative refractive index and the negative permeability of the nanopillar sample in the visible range.

  20. Creating Materials with Negative Refraction Index using Topology Optimization

    DEFF Research Database (Denmark)

    Christiansen, Rasmus Ellebæk; Sigmund, Ole

    We apply topology optimization along with full modeling of the electromagnetic (acoustic) field to create metamaterials with negative refraction index. We believe that our approach can be used in the design of metamaterials with specific effective permittivity and permeability e.g. by adapting...... is on the order of the wavelength. We seek a distribution of solid and air in the design cell yielding a prescribed negative refraction index for the slab. Our objective is to minimize the difference in amplitude between the solution to the model problemand a prescribed modulated plane wave behind the slab....... The direction of propagation for the prescribed wave is chosen to match the angle of incidence of the incoming plane wave and its position isused to select the refraction index for the slab. We introducing a continuous design field and apply The Method of Moving Asymptotes to perform the optimization. A filter...

  1. Origami with negative refractive index to generate super-lenses.

    Science.gov (United States)

    Guenneau, Fanny; Chakrabarti, Sangeeta; Guenneau, Sebastien; Ramakrishna, S Anantha

    2014-10-08

    Negative refractive index materials (NRIM) enable unique effects including superlenses with a high degree of sub-wavelength image resolution, a capability that stems from the ability of NRIM to support a host of surface plasmon states. Using a generalized lens theorem and the powerful tools of transformational optics, a variety of focusing configurations involving complementary positive and negative refractive index media can be generated. A paradigm of such complementary media are checkerboards that consist of alternating cells of positive and negative refractive index, and are associated with very singular electromagnetics. We present here a variety of multi-scale checkerboard lenses that we call origami lenses and investigate their electromagnetic properties both theoretically and computationally. Some of these meta-structures in the plane display thin bridges of complementary media, and this highly enhances their plasmonic response. We demonstrate the design of three-dimensional checkerboard meta-structures of complementary media using transformational optics to map the checkerboard onto three-dimensional corner lenses, the only restriction being that the corresponding unfolded structures in the plane are constrained by the four color-map theorem.

  2. Three-dimensional optical metamaterial with a negative refractive index.

    Science.gov (United States)

    Valentine, Jason; Zhang, Shuang; Zentgraf, Thomas; Ulin-Avila, Erick; Genov, Dentcho A; Bartal, Guy; Zhang, Xiang

    2008-09-18

    Metamaterials are artificially engineered structures that have properties, such as a negative refractive index, not attainable with naturally occurring materials. Negative-index metamaterials (NIMs) were first demonstrated for microwave frequencies, but it has been challenging to design NIMs for optical frequencies and they have so far been limited to optically thin samples because of significant fabrication challenges and strong energy dissipation in metals. Such thin structures are analogous to a monolayer of atoms, making it difficult to assign bulk properties such as the index of refraction. Negative refraction of surface plasmons was recently demonstrated but was confined to a two-dimensional waveguide. Three-dimensional (3D) optical metamaterials have come into focus recently, including the realization of negative refraction by using layered semiconductor metamaterials and a 3D magnetic metamaterial in the infrared frequencies; however, neither of these had a negative index of refraction. Here we report a 3D optical metamaterial having negative refractive index with a very high figure of merit of 3.5 (that is, low loss). This metamaterial is made of cascaded 'fishnet' structures, with a negative index existing over a broad spectral range. Moreover, it can readily be probed from free space, making it functional for optical devices. We construct a prism made of this optical NIM to demonstrate negative refractive index at optical frequencies, resulting unambiguously from the negative phase evolution of the wave propagating inside the metamaterial. Bulk optical metamaterials open up prospects for studies of 3D optical effects and applications associated with NIMs and zero-index materials such as reversed Doppler effect, superlenses, optical tunnelling devices, compact resonators and highly directional sources.

  3. Overcoming losses with gain in a negative refractive index metamaterial.

    Science.gov (United States)

    Wuestner, Sebastian; Pusch, Andreas; Tsakmakidis, Kosmas L; Hamm, Joachim M; Hess, Ortwin

    2010-09-17

    On the basis of a full-vectorial three-dimensional Maxwell-Bloch approach we investigate the possibility of using gain to overcome losses in a negative refractive index fishnet metamaterial. We show that appropriate placing of optically pumped laser dyes (gain) into the metamaterial structure results in a frequency band where the nonbianisotropic metamaterial becomes amplifying. In that region both the real and the imaginary part of the effective refractive index become simultaneously negative and the figure of merit diverges at two distinct frequency points.

  4. Negative refractive index metamaterials aided by extraordinary optical transmission.

    Science.gov (United States)

    García-Meca, C; Ortuño, R; Rodríguez-Fortuño, F J; Martí, J; Martínez, A

    2009-04-13

    We study under which conditions extraordinary optical transmission (EOT) structures can be used to build negative refractive index media. As a result, we present a metamaterial with superimposed EOT and negative index at visible wavelengths. The tailoring process starting from a simple hole array until achieving the negative index is detailed. We also discuss the so-called fishnet metamaterial (previously linked to EOT) under the same prism. Using the ideas put forward in this work, other structures with negative index could be engineered in the optical or visible spectrum.

  5. Negative refractive index induced by percolation in disordered metamaterials

    CERN Document Server

    Slovick, Brian A

    2016-01-01

    An effective medium model is developed for disordered metamaterials containing a spatially random distribution of dielectric spheres. Similar to effective medium models for ordered metamaterials, this model predicts resonances in the effective permeability and permittivity arising from electric- and magnetic-dipole Mie resonances in the spheres. In addition, the model predicts a redshift of the electric resonance with increasing particle loading. Interestingly, when the particle loading exceeds the percolation threshold of 33\\%, the model predicts that the electric resonance overlaps with the magnetic resonance, resulting in a negative refractive index.

  6. Negative refractive index induced by percolation in disordered metamaterials

    Science.gov (United States)

    Slovick, Brian A.

    2017-03-01

    An effective medium model is developed for disordered metamaterials containing a spatially random distribution of dielectric spheres. Similar to effective medium models for ordered metamaterials, this model predicts resonances in the effective permeability and permittivity arising from electric- and magnetic-dipole Mie resonances in the spheres. In addition, the model predicts a redshift of the electric resonance with increasing particle loading. Interestingly, when the particle loading exceeds the percolation threshold of 33%, the model predicts that the electric resonance overlaps with the magnetic resonance, resulting in a negative refractive index.

  7. Numerical Study of Negative-Refractive Index Ferrite Waveguide

    Directory of Open Access Journals (Sweden)

    Mohammed O. Sid-Ahmed

    2012-03-01

    Full Text Available Consider a magnetized ferrite-wire waveguide structure situated between two half free spaces. Ferrites to provide negative permeability and wire array to provide negative permittivity. The structure form left-handed material (LHM with negative refractive index. The transmission of electromagnetic waves through the structure is investigated theoretically. Maxwell's equations are used to determine the electric and magnetic fields of the incident waves at each layer. Snell's law is applied and the boundary conditions are imposed at each layer interface to calculate the reflected and transmitted powers of the structure. Numerical results are illustrated to show the effect of frequency, applied magnetic fields, angle of incidence and LHM thickness on the mentioned powers. The analyzed results show that the transmission is very good when the permeability and permittivity of the structure are both simultaneously negative. The frequency band corresponding to this transmission can be tuned by changing the applied magnetic fields. The obtained results are in agreement with the law of conservation of energy. Consider a magnetized ferrite-wire waveguide structure situated between two half free spaces. Ferrites to provide negative permeability and wire array to provide negative permittivity. The structure form left-handed material (LHM with negative refractive index. The transmission of electromagnetic waves through the structure is investigated theoretically. Maxwell's equations are used to determine the electric and magnetic fields of the incident waves at each layer. Snell's law is applied and the boundary conditions are imposed at each layer interface to calculate the reflected and transmitted powers of the structure. Numerical results are illustrated to show the effect of frequency, applied magnetic fields, angle of incidence and LHM thickness on the mentioned powers. The analyzed results show that the transmission is very good when the permeability and

  8. Towards a Negative Refractive Index in an Atomic System

    Science.gov (United States)

    Simmons, Zach; Brewer, Nick; Yavuz, Deniz

    2014-05-01

    The goal of our experiments is to obtain a negative index of refraction in the optical region of the spectrum using an atomic system. The concept of negative refraction, which was first predicted by Veselago more than four decades ago, has recently emerged as a very exciting field of science. Negative index materials exhibit many seemingly strange properties such as electromagnetic vectors forming a left-handed triad. A key potential application for these materials was discovered in 2000 when Pendry predicted that a slab with a negative refractive index can image objects with a resolution far better than the diffraction limit. Thus far, research in negative index materials has primarily focused on meta-materials. The fixed response and often large absorption of these engineered materials motivates our efforts to work in an atomic system. An atomic media offers the potential to be actively modified, for example by changing laser parameters, and can be tuned to cancel absorption. A doped crystal allows for high atomic densities compared to other atomic systems. So far we have identified a transition in such a material, Eu:YSO, as a candidate for these experiments and are performing spectroscopy on this material.

  9. Design and fabrication activity towards 3D negative refraction index materials in the IR region

    DEFF Research Database (Denmark)

    Malureanu, Radu; Andryieuski, Andrei; Lavrinenko, Andrei

    2009-01-01

    In this paper we present a new 3D isotropic structure that allows obtaining negative refraction index in the telecom wavelength as well as first fabrication efforts towards obtaining such structures.......In this paper we present a new 3D isotropic structure that allows obtaining negative refraction index in the telecom wavelength as well as first fabrication efforts towards obtaining such structures....

  10. Feasibility study for pseudoscopic problem in integral imaging using negative refractive index materials.

    Science.gov (United States)

    Zhang, JianLei; Wang, XiaoRui; Chen, YuJiao; Zhang, QiPing; Yu, Shuo; Yuan, Ying; Guo, BingTao

    2014-08-25

    To solve the pseudoscopic problem, we propose a one-step integral imaging system with negative refractive index materials, which can avoid the deterioration in resolution inherent to the optical or digital two-step processes. Specifically, the proposed method is based on the novel feature of negative refractive index materials, bending light to a negative angle relative to the surface normal. The pseudoscopic imaging property of the negative refractive index material slab is theoretically investigated. For formation of orthoscopic reconstructed images, the matching condition of the negative index lens array and the positive index lens array is deduced. Two types of conceptual prototypes of integral imaging system with negative refractive index materials are designed. Experimental results show the validity of the proposed method. To the best of our knowledge, this is the first time to explore the application of negative index materials in eliminating the pseudoscopic effect in integral imaging.

  11. Spin angular momentum transfer from TEM(00) focused Gaussian beams to negative refractive index spherical particles.

    Science.gov (United States)

    Ambrosio, Leonardo A; Hernández-Figueroa, Hugo E

    2011-08-01

    We investigate optical torques over absorbent negative refractive index spherical scatterers under the influence of linear and circularly polarized TEM(00) focused Gaussian beams, in the framework of the generalized Lorenz-Mie theory with the integral localized approximation. The fundamental differences between optical torques due to spin angular momentum transfer in positive and negative refractive index optical trapping are outlined, revealing the effect of the Mie scattering coefficients in one of the most fundamental properties in optical trapping systems.

  12. Theory of negative-refractive-index response of double-fishnet structures.

    Science.gov (United States)

    Mary, A; Rodrigo, Sergio G; Garcia-Vidal, F J; Martin-Moreno, L

    2008-09-05

    A theory is presented of the negative refractive index observed in the so-called double-fishnet structures. We find that the electrical response of these structures is dominated by the cutoff frequency of the hole waveguide whereas the resonant magnetic response is due to the excitation of gap surface plasmon polaritons propagating along the dielectric slab. Associated with this origin, we show how the negative refractive index in these metamaterials presents strong dispersion with the parallel momentum of the incident light.

  13. Experimental characterization of negative refractive index material NRM at Ka band

    CERN Document Server

    Chatterjee, Sougata

    2016-01-01

    In this paper, we discuss the experimental characterization of a negative refractive material NRM at Ka band using LR labyrinth Ring and wire array WA. We describe in detail the the LR and wire array characterization separately, and after that the combined experimental results, for NRM are reported. The LRs analytical and simulation study is not new but design in Ka band and different experimental procedure for the characterization of the negative refractive index is the novelty of this paper. For performing a negative refractive index experiment we made prism of 150 Prism angle . We get enhanced transmittance of more than 20 dB from background, at a negative angle of refraction. The values of the negative refractive index in a band of about 1 G Hz around 31 GHz are retrieved from the experimental data.

  14. An anisotropic negative refractive index medium operated at multiple-angle incidences.

    Science.gov (United States)

    Yang, Tien-Chung; Yang, Yu-Hang; Yen, Ta-Jen

    2009-12-21

    Recently metamaterials have been demonstrating new physics to enable various unprecedented electromagnetic properties, but pratically they are so sensitive to incident angles of the external excitation that their applications are restricted. Therefore, we present an anisotropic negative refractive index medium operated at multiple-angle incidences (NRIM for MAI) to ease such a burden. Both the simulated and measured transmittance, reflectance and the corresponding material parameters indicate that our structure does possess the anisotropic negative refractive index with respect to different incident angles. In addition, the opposite directions of group and phase velocities are also demonstrated under both grazing-angle, normal and 45-degree incidences to further verify the negative refractive index of the designed monolithic NRIM structure for multiple-angle incidences.

  15. Electromagnetic scattering by spherical negative-refractive-index particles: Low-frequency resonance and localization parameters.

    Science.gov (United States)

    Liu, Zheng; Lin, Zhifang; Chui, S T

    2004-01-01

    The Mie scattering of electromagnetic waves of wave vector k by spherical negative-refractive-index particles of radius a exhibits an unusual resonance at ka-->0. The scattering enhancement from the ka-->0 resonance is insensitive to the size of scatterers, distinct from the Mie scattering resonances from positive-refractive-index particles. For media consisting of a collection of the negative-refractive-index particles, the unusual resonance results in a significant reduction of the localization parameter, providing a possibility to reach the light localization transition by reducing the wave vector k, in analogy to electronic systems.

  16. Design of fiber metamaterials with negative refractive index in the infrared.

    Science.gov (United States)

    Townsend, Scott; Zhou, Shiwei; Li, Qing

    2015-07-13

    Metamaterials possess intricate, sub-wavelength microstructures, making scalability a salient concern in regard to their practicality. Fiber-drawing offers a route to producing large quantities of material at relatively low cost, though to our knowledge, a fiber-based design capable of negative refractive index behaviour has not yet been proposed. We submit that the electric and magnetic dipole resonance modes of the fiber can be enhanced by including in the fiber aligned metallic inclusions. Addition of a solid metallic core can effect a synchronisation of these modes, allowing a collection of the fibers to possess negative refractive index.

  17. Probing negative refractive index of metamaterials by terahertz time-domain spectroscopy.

    Science.gov (United States)

    Han, Jiaguang

    2008-01-21

    Terahertz time-domain spectroscopy (THz-TDS) offers a new perspective for extraction of negative refractive index of low-loss metamaterials directly. We present the detailed extraction procedure how to obtain the negative refractive index of metamaterials through THz-TDS measurement. The basic equations are deduced to obtain the negative index through comparison of THz data measured for the sample and reference, respectively. Further simulation examples matching the practical experimental cases are given, which verifies that the extraction procedure is reliable. This approach demonstrates the potential use of THz-TDS in study of metamaterials and is helpful for design of metamaterial devices.

  18. Traversal of electromagnetic pulses through dispersive media with negative refractive index

    Science.gov (United States)

    Nanda, L.; Ramakrishna, S. A.

    2017-05-01

    We investigate the traversal of electromagnetic pulses through dispersive media with negative refractive index in such a way that no resonant effects come into play. It has been verified that for evanescent waves, the definitions of the group delay and the reshaping delay times get interchanged in comparison to the propagating waves. We show that for a negative refractive index medium (NRM) with ɛ(ω)=μ(ω), the reshaping delay time identically vanishes for propagating waves. The total delay time in NRM is otherwise contributed by both the group and the reshaping delay times, whereas for the case of broadband pulses in NRM the total delay time is always subluminal.

  19. Bi-layer cross chiral structure with strong optical activity and negative refractive index.

    Science.gov (United States)

    Dong, Jianfeng; Zhou, Jiangfeng; Koschny, Thomas; Soukoulis, Costas

    2009-08-03

    The properties of periodic pairs of mutually twisted metallic (silver) crosses separated by dielectric layer have been investigated by numerical simulation. The results show that the exceptionally strong polarization rotation and circular dichroism, negative permeability and negative refractive index are found at the infrared communication wavelength (1.55 microm).

  20. Simulations and realizations of active right-handed metamaterials with negative refractive index.

    Science.gov (United States)

    Nistad, Bertil; Skaar, Johannes

    2007-08-20

    The theory of determining the sign of the refractive index in active materials is discussed. Animations of numerical simulations are presented, supporting the claim that negative refractive index may occur in right-handed media. An example of such a medium, in the form of a lumped circuit model with active and passive resonances, is presented.

  1. Spectral response of Cantor multilayers made of materials with negative refractive index

    OpenAIRE

    Gerardin, Jaline; Lakhtakia, Akhlesh

    2002-01-01

    Whereas Cantor multilayers made of an isotropic dielectric-magnetic material with positive refractive index will show power-law characteristics, low-order Cantor multilayers made of materials with negative refractive index will not exhibit the power-law nature. A reason for this anomalous behavior is presented.

  2. Simulations and realizations of active right-handed metamaterials with negative refractive index

    OpenAIRE

    Nistad, Bertil; Skaar, Johannes

    2007-01-01

    The theory of determining the sign of the refractive index in active materials is discussed. Animations of numerical simulations are presented, supporting the claim that negative refractive index may occur in right-handed media. An example of such a medium, in the form of a lumped circuit model with active and passive resonances, is presented.

  3. Deposited metamaterial thin film with negative refractive index and permeability in the visible regime.

    Science.gov (United States)

    Jen, Yi-Jun; Chen, Chih-Hui; Yu, Ching-Wei

    2011-03-15

    Thin films are fabricated from arrays of silver nanorods with thicknesses of 160 nm and 200 nm, to function as a metamaterial. The negative refractive index and negative permeability are retrieved from measured reflection and transmission coefficients using walk-off interferometer in the visible regime. A negative-index-material thin film with negative permittivity or (and) permeability can be produced by glancing angle deposition.

  4. Long wave-short wave resonance in nonlinear negative refractive index media.

    Science.gov (United States)

    Chowdhury, Aref; Tataronis, John A

    2008-04-18

    We show that long wave-short wave resonance can be achieved in a second-order nonlinear negative refractive index medium when the short wave lies on the negative index branch. With the medium exhibiting a second-order nonlinear susceptibility, a number of nonlinear phenomena such as solitary waves, paired solitons, and periodic wave trains are possible or enhanced through the cascaded second-order effect. Potential applications include the generation of terahertz waves from optical pulses.

  5. Negative refraction and Negative refractive index in an optical uniaxial absorbent medium

    OpenAIRE

    Jen, Yi-Jun; Yu, Ching-Wei; Lin, Chin-Te

    2009-01-01

    This work demonstrates the existence of both negative refraction and a negative refractive index in an optical uniaxial absorbent medium that can be characterized by ordinary and extraordinary refractive indices. Negative refraction occurs in any absorbent uniaxial medium if the real part of the extraordinary index is less than its imaginary part. The refractive index is negative when the incident medium is sufficiently dense and the incident angle exceeds a critical angle that is defined here.

  6. Optic-null space medium for cover-up cloaking without any negative refraction index materials

    OpenAIRE

    Fei Sun; Sailing He

    2016-01-01

    With the help of optic-null medium, we propose a new way to achieve invisibility by covering up the scattering without using any negative refraction index materials. Compared with previous methods to achieve invisibility, the function of our cloak is to cover up the scattering of the objects to be concealed by a background object of strong scattering. The concealed object can receive information from the outside world without being detected. Numerical simulations verify the performance of our...

  7. A novel approach to design microwave medium of negative refractive index and simulation verification

    Institute of Scientific and Technical Information of China (English)

    CAO YunJian; WEN GuangJun; WU KaiMin; XU XinHe

    2007-01-01

    In this paper, a novel approach is presented to synthesize microwave medium of negative refractive index by incorporating metallic wire array with negative effective permittivity into the host media such as ferrimagnet-YIG (yttrium iron garnet) applied by external magnetic field whose permeability is negative. We have designed the composite medium having negative refractive index in C/X band frequencies, analyzed and simulated its electromagnetic (EM) properties by use of EM EDA package based on time-domain finite integration method. The simulation results show that: ① the effective permittivity of the designed metallic wire array is negative in the frequency range from 7.02 GHz to 9.80 GHz; ② the permeability of YIG substrate immersed into an external magnetic field is negative in the frequency range from 5.22 GHz to 8.14 GHz; ③ EM wave can pass through the composite medium synthesized by the above designed metallic wire array and YIG substrate, and ④ the negative refraction behavior occurs on the interface between the composite medium and the normal material with positive refractive index in 7.51-8.13 GHz frequency range, in which the effective permittivity of the metallic wire array and the permeability of YIG substrate are negative simultaneously. The full wave simulation has demonstrated that the effective refractive index of the designed composite medium is indeed negative and ascertained that the proposed approach to design microwave medium with negative refractive index is viable.

  8. Nonlinear wave mixing and susceptibility properties of negative refractive index materials.

    Science.gov (United States)

    Chowdhury, Aref; Tataronis, John A

    2007-01-01

    We present an analysis of second-order and third-order nonlinear susceptibilities and wave-mixing properties of negative refractive index materials. We show that the nonlinear susceptibilities for noncentrosymmetric and centrosymmetric media may be positive or negative and away from resonance depending on the frequency of interest relative to the resonant frequencies of the material. Manipulation of the signs of the nonlinear susceptibilities is important in the field of optics, particularly for solitons and compensation of nonlinear effects. We also show that three- and four-wave mixing can be naturally phase matched in the material.

  9. Low-loss and high-symmetry negative refractive index media by hybrid dielectric resonators.

    Science.gov (United States)

    Lai, Yueh-Chun; Chen, Cheng-Kuang; Yang, Yu-Hang; Yen, Ta-Jen

    2012-01-30

    Based on Maxwell's equations and Mie theory, strong sub-wavelength artificial magnetic and electric dipole resonances can be excited within dielectric resonators, and their resonant frequencies can be tailored simply by scaling the size of the dielectric resonators. Therefore, in this work we hybridize commercially available zirconia and alumina structures to harvest their individual artificial magnetic and electric response simultaneously, presenting a negative refractive index medium (NRIM). Comparing with the conventional NRIM constructed by metallic structures, the demonstrated all-dielectric NRIM possesses low-loss and high-symmetry advantages, thus benefiting practical applications in communication components, perfect lenses, invisible cloaking and other novel electromagnetic devices.

  10. Optic-null space medium for cover-up cloaking without any negative refraction index materials

    Science.gov (United States)

    Sun, Fei; He, Sailing

    2016-07-01

    With the help of optic-null medium, we propose a new way to achieve invisibility by covering up the scattering without using any negative refraction index materials. Compared with previous methods to achieve invisibility, the function of our cloak is to cover up the scattering of the objects to be concealed by a background object of strong scattering. The concealed object can receive information from the outside world without being detected. Numerical simulations verify the performance of our cloak. The proposed method will be a great addition to existing invisibility technology.

  11. Ultra-compact chiral metamaterial with negative refractive index based on miniaturized structure

    Science.gov (United States)

    Li, Minhua; Song, Jian; Wu, Fei

    2017-03-01

    An ultra-compact chiral metamaterial with thin thickness and small unit cells is proposed. Echelon meandered conjugated gammadions are introduced into the planar miniaturized design. In particular, the ratio between period (p) and resonant wavelength (λ) is as small as 1/10.8 in experiment. Negative refractive indexes for circularly polarized waves are demonstrated and the effective parameters are retrieved. The effects of the length of the swing arms, number of folded lines and dielectric layer thickness on the optical activity have also been investigated. This miniaturized structure has great potential application in electronic and photonic devices with small size and integration.

  12. Design of fishnet metamaterials with broadband negative refractive index in the visible spectrum.

    Science.gov (United States)

    Zhou, Shiwei; Townsend, Scott; Xie, Yi Min; Huang, Xiaodong; Shen, Jianhu; Li, Qing

    2014-04-15

    We propose a technique capable of designing fishnet metamaterials that have a negative refractive index (NRI) over a broad range in the visible and infrared. The technique relies on optimizing the shape and scale of the fishnet apertures as well as the depth of different layers of the composite. A metamaterial is obtained that exhibits an unbroken 552 nm bandwidth of NRI, covering the entire red and infrared regions. Moreover, two fishnet structures perforated with star-like holes are found to render refractive index negative in the yellow and green spectra.

  13. Causality-based criteria for a negative refractive index must be used with care.

    Science.gov (United States)

    Kinsler, P; McCall, M W

    2008-10-17

    Using the principle of causality as expressed in the Kramers-Kronig relations, we derive a generalized criterion for a negative refractive index that admits imperfect transparency at an observation frequency omega. It also allows us to relate the global properties of the loss (i.e., its frequency response) to its local behavior at omega. However, causality-based criteria rely on the group velocity, not the Poynting vector. Since the two are not equivalent, we provide some simple examples to compare the two criteria.

  14. Free-standing terahertz chiral meta-foils exhibiting strong optical activity and negative refractive index

    Science.gov (United States)

    Wu, Jianfeng; Ng, Binghao; Turaga, Shuvan P.; Breese, Mark B. H.; Maier, Stefan A.; Hong, Minghui; Bettiol, Andrew A.; Moser, Herbert O.

    2013-09-01

    A chiral meta-foil consisting of a self-supported square array of interconnected conjugated rosettes is demonstrated at terahertz frequencies. It exhibits strong optical activity and circular dichroism. Negative refractive index with a figure-of-merit as high as 4.2 is achieved, attributed to its free-standing nature. Experimental results are in good agreement with numerical simulation. Free-standing chiral meta-foils provide a unique approach to create a completely all-metal chiral metamaterial, which can be flexibly integrated into optical setups while eliminating dielectric insertion losses.

  15. Study on Microcavity Organic Light-emitting Devices Containing Negative Refractive Index Dielectric Layer

    Institute of Scientific and Technical Information of China (English)

    CAI Hong-xin; LI Li-xin

    2009-01-01

    A new structure containing negative refractive index dielectric layer(NRIDL) is introduced into microcavity.The properties of the new microcavity organic light-emitting devices(MOLEDs) are investigated.In the experiment,the transfer matrix method is adopted.The dependence of reflectance and transmittance on the refractive index and thickness of NRIDL are analyzed in detail.Compared with the electroluminescence spectra of non-NRIDL diodes,the line widths of the spectra of the MOLEDs are narrower and all the peaks enhance.The results show that the new structure is beneficial to improve the performance and reduce the thickness of microcavity devices.

  16. Cavity equations for a positive- or negative-refraction-index material with electric and magnetic nonlinearities

    Science.gov (United States)

    Mártin, Daniel A.; Hoyuelos, Miguel

    2009-11-01

    We study evolution equations for electric and magnetic field amplitudes in a ring cavity with plane mirrors. The cavity is filled with a positive or negative-refraction-index material with third-order effective electric and magnetic nonlinearities. Two coupled nonlinear equations for the electric and magnetic amplitudes are obtained. We prove that the description can be reduced to one Lugiato-Lefever equation with generalized coefficients. A stability analysis of the homogeneous solution, complemented with numerical integration, shows that any combination of the parameters should correspond to one of three characteristic behaviors.

  17. Causality-based criteria for a negative refractive index must be used with care

    CERN Document Server

    Kinsler, P; 10.1103/PhysRevLett.101.167401

    2008-01-01

    Using the principle of causality as expressed in the Kramers-Kronig relations, we derive a generalized criterion for a negative refractive index that admits imperfect transparency at an observation frequency $\\omega$. It also allows us to relate the global properties of the loss (i.e. its frequency response) to its local behaviour at $\\omega$. However, causality-based criteria rely the on the group velocity, not the Poynting vector. Since the two are not equivalent, we provide some simple examples to compare the two criteria.

  18. A three-dimensional self-supporting low loss microwave lens with a negative refractive index

    Science.gov (United States)

    Ehrenberg, Isaac M.; Sarma, Sanjay E.; Wu, Bae-Ian

    2012-10-01

    Demonstrations of focusing with metamaterial lenses have predominantly featured two dimensional structures or stacks of planar elements, both limited by losses which hinder realized gain near the focal region. In this study, we present a plano-concave lens built from a 3D self-supporting metamaterial structure featuring a negative refractive index between 10 and 12 GHz. Fabricated using macroscopic layered prototyping, the lens curvature, negative index and low loss contribute to a recognizable focus and free space gains above 13 dB.

  19. Optic-null space medium for cover-up cloaking without any negative refraction index materials.

    Science.gov (United States)

    Sun, Fei; He, Sailing

    2016-07-07

    With the help of optic-null medium, we propose a new way to achieve invisibility by covering up the scattering without using any negative refraction index materials. Compared with previous methods to achieve invisibility, the function of our cloak is to cover up the scattering of the objects to be concealed by a background object of strong scattering. The concealed object can receive information from the outside world without being detected. Numerical simulations verify the performance of our cloak. The proposed method will be a great addition to existing invisibility technology.

  20. Three-layered metallodielectric nanoshells: plausible meta-atoms for metamaterials with isotropic negative refractive index at visible wavelengths.

    Science.gov (United States)

    Wu, DaJian; Jiang, ShuMin; Cheng, Ying; Liu, XiaoJun

    2013-01-14

    A three-layered Ag-low-permittivity (LP)-high-permittivity (HP) nanoshell is proposed as a plausible meta-atom for building the three-dimensional isotropic negative refractive index metamaterials (NIMs). The overlap between the electric and magnetic responses of Ag-LP-HP nanoshell can be realized by designing the geometry of the particle, which can lead to the negative electric and magnetic polarizabilities. Then, the negative refractive index is found in the random arrangement of Ag-LP-HP nanoshells. Especially, the modulation of the middle LP layer can move the negative refractive index range into the visible region. Because the responses arise from the each meta-atom, the metamaterial is intrinsically isotropic and polarization independent. It is further found with the increase of the LP layer thickness that the negative refractive index range of the random arrangement shows a large blue-shift and becomes narrow. With the decrease of the filling fraction, the negative refractive index range shows a blue-shift and becomes narrow while the maximum of the negative refractive index decreases.

  1. Photonic band gaps in quasiperiodic photonic crystals with negative refractive index

    Science.gov (United States)

    Vasconcelos, M. S.; Mauriz, P. W.; de Medeiros, F. F.; Albuquerque, E. L.

    2007-10-01

    We investigate the photonic band gaps in quasiperiodic photonic crystals made up of both positive (SiO2) and negative refractive index materials using a theoretical model based on a transfer matrix treatment. The quasiperiodic structures are characterized by the nature of their Fourier spectrum, which can be dense pure point (Fibonacci sequences) or singular continuous (Thue-Morse and double-period sequences). These substitutional sequences are described in terms of a series of generations that obey peculiar recursion relations. We discussed the photonic band gap spectra for both the ideal cases, where the negative refractive index material can be approximated as a constant in the frequency range considered, as well as the more realistic case, taking into account the frequency-dependent electric permittivity γ and magnetic permeability μ . We also present a quantitative analysis of the results, pointing out the distribution of the allowed photonic bandwidths for high generations, which gives a good insight about their localization and power laws.

  2. Topological insulator metamaterials with tunable negative refractive index in the optical region.

    Science.gov (United States)

    Cao, Tun; Wang, Shuai

    2013-12-13

    A blueshift tunable metamaterial (MM) exhibiting a double-negative refractive index based on a topological insulator (bismuth selenide, Bi2Se3) has been demonstrated in the near-infrared (NIR) spectral region. The potential of Bi2Se3 as a dielectric interlayer of the multilayer MM is explored. The optical response of elliptical nanohole arrays penetrating through Au/Bi2Se3/Au films is numerically investigated using the finite difference time domain (FDTD) method. The blueshift tuning range of the MM is as high as 370 nm (from 2,140 to 1,770 nm) after switching the Bi2Se3 between its trigonal and orthorhombic states.

  3. Symmetry relations in the generalized Lorenz-Mie theory for lossless negative refractive index media

    Science.gov (United States)

    André Ambrosio, Leonardo

    2016-09-01

    In this paper we present a theoretical analysis of the generalized Lorenz-Mie theory for negative refractive index (NRI) media and spherical scatterers, extending the well-known concepts and definitions found in the literature involving dielectric or positive refractive index (PRI) particles. The consequences of a negative phase velocity and an anti-parallelism of the wave vector with respect to the Poynting vector are investigated and interpreted in this framework and, together with the symmetries found for the beam-shape coefficients when compared to the conventional PRI case, it is shown that the description of plane waves, Gaussian beams and, more generally, on-axis azimuthally symmetric waves along a NRI medium, their fields and all physical properties can be conveniently correlated with that of dielectric media once the electromagnetic response functions are replaced by their corresponding dielectric counterparts.

  4. Transmission spectra of one-dimensional photonic crystals including negative-refractive-index media

    Institute of Scientific and Technical Information of China (English)

    SHEN Xiao-ming; CHEN Xian-feng; JIANG Mei-ping; SHI Du-fang

    2005-01-01

    We introduce a new model of one-dimensional (1D) photonic crystal composed of alternately arranged RHM and LHM layers with positive and negative refractive indices respectively, for which the transmission spectra of the model are calculated numerically with the transfer matrix method, and the band-gap structure and the polarization properties are analyzed. We found that the introduction of negative refractive index layers (i.e.LHM medium layers) gives rise to some peculiar band-gap structure and polarization properties as follows. Firstly, the forbidden bands are extremely wide and the transmission bands are very sharp without oscillation;and secondly, the change of incident angle has different influences on the forbidden bands of TE and TM modes. For the TM mode, the forbidden band width decreases substantially and finally vanishes, and for the TE mode with central wavelength, the total reflection happens at any incident angle.

  5. Miniaturisation of WLAN Feeler Using Media with a Negative Refractive Index

    Directory of Open Access Journals (Sweden)

    Bimal Garg

    2013-07-01

    Full Text Available It presents a rectangular microstrip patch antenna integrated with combination of pentagonal and hexagonal shaped structure etched at the height of 3.276 mm from the ground plane. It is demonstrated that the application of the media with a negative refractive index or metamaterial eliminates the spurious harmonics (these are those unwanted dips which shows in the S11 graph associated with the original structure. Furthermore the return loss is improved by the inclusion of the metamaterial structure reaching -27.1919 dB compared with -10.1286 dB achieved by the original patch antenna structure alone. Main focus in this design process is not to reduce the return loss but reduce the size of the antenna and this target has been achieved by reducing the size of antenna up to 65%. Numerical simulation results show that this proposed design possesses several desirable characteristics, for instance, high bandwidth, low loss and improved directivity compared to the alone RMPA. The CST-MWS software is used for designing and simulation, and MS-Excel for metamaterial proving.

  6. A negative refractive index metamaterial wave plate for millimetre-wave applications

    Science.gov (United States)

    Mohamed, I.; Pisano, G.; Ng, M. W.; Maffei, B.; Haynes, V.; Ozturk, F.

    2012-09-01

    By use of a metamaterial based on the ‘cut wire pair’ geometry, highly birefringent wave plates may be constructed by virtue of the geometry’s ability of having a negative and positive refractive index along its perpendicular axes. Past implementations have been narrow band in nature due to the reliance on producing a resonance to achieve a negative refractive index band and the steep gradient in the phase difference that results. In this paper we attempt to design and manufacture a W-band quarter wave plate embedded in polypropylene that applies the Pancharatnam method to increase the useable bandwidth. Our modelling demonstrates that a broadening of the phase difference’s bandwidth defined as the region 90° +/- 2° is possible from 0.6% (101.7 GHz - 102.3 GHz) to 7.8% (86.2 GHz - 93.1 GHz). Our experimental results show some agreement with our modelling but differ at higher frequencies.

  7. MgB2 -based negative refraction index metamaterial at visible frequencies: Theoretical analysis

    Science.gov (United States)

    Kussow, Adil-Gerai; Akyurtlu, Alkim; Semichaevsky, Andrey; Angkawisittpan, Niwat

    2007-11-01

    The presented metamaterial consists of the matrix (magnesium diboride MgB2 in a normal state, at room temperature) with randomly (or regularly) embedded spherical nanoparticles of a polaritonic crystal, SiC. The calculations demonstrate explicitly that the metamaterial exhibits negative refraction index behavior with low losses for a scattered wave. The result stands for both random and regular distributions of SiC nanoparticles inside the MgB2 matrix. This favorable situation stems from the Drude-like behavior of both the low-energy, p2(ωp2≈1.9eV) , and the high-energy, p1(ωp1≈6.3eV) , plasmon modes of MgB2 with plasmon losses, γ⩽0.25eV . The effective medium parameters were calculated in the framework of the extended theories of Maxwell-Garnett [Philos. Trans. R. Soc. London, Ser. A 203, 385 (1904)] and Lewin [Proc. Inst. Electr. Eng. 94, 65 (1947)], and the obtained results are validated via ab initio finite difference time domain simulations.

  8. How to realize a negative refractive index material at the atomic level in an optical frequency range?

    Science.gov (United States)

    Shen, Jian-qi; Ruan, Zhi-chao; He, Sai-ling

    2004-11-01

    The theoretical mechanism for realizing a negative refractive index material in an optical frequency range with an atomic gas system of electromagnetically induced transparency (EIT) is studied. It is shown that under certain conditions such a dense gas can exhibit simultaneously negative permittivity and negative permeability, and negligibly small loss.

  9. Science Letters: How to realize a negative refractive index material at the atomic level in an optical frequency range?

    Institute of Scientific and Technical Information of China (English)

    沈建其; 阮智超; 何赛灵

    2004-01-01

    The theoretical mechanism for realizing a negative refractive index material in an optical frequency range with an atomic gas system of electromagnetically induced transparency (EIT) is studied. It is shown that under certain conditions such a dense gas can exhibit simultaneously negative permittivity and negative permeability, and negligibly small loss.

  10. EM transmission-line metamaterials

    Directory of Open Access Journals (Sweden)

    George V. Eleftheriades

    2009-03-01

    Full Text Available Metamaterials are understood to be artificially engineered materials that exhibit unusual or difficult to obtain electromagnetic (EM properties. Such properties would include negative or low values of permittivity, permeability and index of refraction. In this article, we review the fundamentals of metamaterials with emphasis on negative-refractive-index ones, which are synthesized using loaded transmission lines. A number of applications of such metamaterials are discussed, including peculiar lenses that can overcome the diffraction limit and small antennas for emerging wireless communication applications.

  11. Metamaterials with tunable negative refractive index fabricated from nanoamorphous ferromagnetic microwires and Magnus optical effect

    Science.gov (United States)

    Ivanov, A.; Shalygin, A.; Galkin, V.; Vedyayev, A.; Rozanov, K.; Ivanov, V.

    2008-08-01

    For inhomogeneous mediums the optical Magnus effect has been derived. The metamaterials fabricated from amorphous ferromagnet Co-Fe-Cr-B-Si microwires are shown to exhibit a negative refractive index for electromagnetic waves over wide scale of GHz frequencies. Optical properties and optical Magnus effect of such metamaterials are tunable by an external magnetic field. Microwave permeability of glass-coated ferromagnetic amorphous microwire exhibiting a weak negative magnetostriction has been studied. The diameter of the microwire was about 20 μm and the diameter of the metal core was about 12 μm. The microwire was wound to comprise a 7/3 washer-shaped composite sample with the volume fraction of magnetic constituent of about 10%. The permeability of the composite sample was measured in a coaxial line in the frequency range from 0.1 to 10 GHz. The composite was found to exhibit a negative permeability within the frequency range from approximately 0.7 to 1.5 GHz, with the permeability being as low as -0.4. Therefore, microwire-based composites, particularly, crossed arrays of microwires may be employed to develop metamaterials for microwave applications. In the composite, the negative microwave permeability is due to the natural ferromagnetic resonance and the negative microwave permittivity is due to the inherent inductance of the wire. Such metamaterials are advantageous in simple design, isotropic in-plane performance, and possible tunability of performance by external magnetic bias. However, for a feasible metamaterial fabricated from microwire arrays, the wires have to exhibit higher magnitude of the ferromagnetic resonance, higher quality factor, and higher resonance frequency.

  12. Cavity equations for a positive or negative refraction index material with electric and magnetic non-linearities

    CERN Document Server

    Mártin, Daniel A; 10.1103/PhysRevE.80.056601

    2012-01-01

    We study evolution equations for electric and magnetic field amplitudes in a ring cavity with plane mirrors. The cavity is filled with a positive or negative refraction index material with third order effective electric and magnetic non-linearities. Two coupled non-linear equations for the electric and magnetic amplitudes are obtained. We prove that the description can be reduced to one Lugiato Lefever equation with generalized coefficients. A stability analysis of the homogeneous solution, complemented with numerical integration, shows that any combination of the parameters should correspond to one of three characteristic behaviors.

  13. Measurements of the negative refractive index of sub-diffraction waves propagating in an indefinite permittivity medium.

    Science.gov (United States)

    Korobkin, Dmitriy; Neuner, Burton; Fietz, Chris; Jegenyes, Nikoletta; Ferro, Gabriel; Shvets, Gennady

    2010-10-25

    An indefinite permittivity medium (IPM) has been fabricated and optically characterized in mid-infrared spectral range (10.7 µm-11.3 µm). Phase and amplitude transmission measurements reveal two remarkable properties of IPMs: (i) transmission of sub-diffraction waves (as short as λ/4) can exceed those of diffraction-limited ones, and (ii) sub-diffraction waves can propagate with negative refractive index. We describe a novel double-detector optical technique relying on the interference between sub-diffraction and diffraction-limited waves for accurate measurement of the transmission amplitude and phase of the former.

  14. Non-linear states of a positive or negative refraction index material in a cavity with feedback

    Science.gov (United States)

    Mártin, D. A.; Hoyuelos, M.

    2010-06-01

    We study a system composed by a cavity with plane mirrors containing a positive or negative refraction index material with third order effective electric and magnetic non-linearities. The aim of the work is to present a general picture of possible non-linear states in terms of the relevant parameters of the system. The parameters are the ones that appear in a reduced description that has the form of the Lugiato-Lefever equation. This equation is obtained from two coupled non-linear Schrödinger equations for the electric and magnetic field amplitudes.

  15. Negative refractive index metamaterials from inherently non-magnetic materials for deep infrared to terahertz frequency ranges.

    Science.gov (United States)

    Yannopapas, Vassilios; Moroz, Alexander

    2005-06-29

    We present a new set of artificial structures which can exhibit a negative refractive index band in excess of 6% in a broad frequency range from the deep infrared to the terahertz region. The structures are composites of two different kinds of non-overlapping spheres, one made from inherently non-magnetic polaritonic and the other from a Drude-like material. The polaritonic spheres are responsible for the existence of negative effective magnetic permeability whilst the Drude-like spheres are responsible for negative effective electric permittivity. The resulting negative refractive index structures are truly subwavelength structures with wavelength-to-structure ratio 14:1, which is almost 50% higher than has been previously achieved. Our results are explained in the context of the extended Maxwell-Garnett theory and are reproduced by calculations based on the layer Korringa-Kohn-Rostoker method, an ab initio multiple scattering theory. The role of absorption in the constituent materials is discussed. Effective medium computer F77 code is freely available at http://www.wave-scattering.com.

  16. Radiation pressure cross sections and optical forces over negative refractive index spherical particles by ordinary Bessel beams.

    Science.gov (United States)

    Ambrosio, Leonardo A; Hernández-Figueroa, Hugo E

    2011-08-01

    When impinged by an arbitrary laser beam, lossless and homogeneous negative refractive index (NRI) spherical particles refract and reflect light in an unusual way, giving rise to different scattered and internal fields when compared to their equivalent positive refractive index particles. In the generalized Lorenz-Mie theory, the scattered fields are dependent upon the Mie scattering coefficients, whose values must reflect the metamaterial behavior of an NRI scatterer, thus leading to new optical properties such as force and torque. In this way, this work is devoted to the analysis of both radial and longitudinal optical forces exerted on lossless and simple NRI particles by zero-order Bessel beams, revealing how the force profiles are changed whenever the refractive index becomes negative.

  17. Tightly coupled tripole conductor pairs as constituents for a planar 2D-isotropic negative refractive index metamaterial.

    Science.gov (United States)

    Vallecchi, Andrea; Capolino, Filippo

    2009-08-17

    A metamaterial, arranged by stacking layers of planar constituents suitably shaped to be responsive to arbitrarily linearly polarized incident waves is here shown to exhibit 2D-isotropic effective negative refractive index (NRI). The general concept underlying this metamaterial design consists of closely pairing two metallic particles to accomplish, as a result of their tight coupling, both symmetric and antisymmetric resonance modes, whose proper superposition can lead to an effective negative refraction response. The proposed structure is composed by layers of periodically arranged pairs of face coupled loaded tripoles printed on the opposite sides of a single dielectric substrate. Through a comprehensive characterization of the transmission properties of such metamaterial, together with the analysis of its dispersion diagram, conclusive evidence that the medium exhibits effective NRI properties as well as good impedance matching to free space is provided. We also describe some guidelines to design the proposed metamaterial with a prescribed operational frequency bandwidth, dependently on the structure parameters.

  18. Resonance-based metamaterial in the shallow sub-wavelength regime: negative refractive index and nearly perfect absorption

    Science.gov (United States)

    Trang Pham, Thi; Nguyen, Hoang Tung; Tuyen Le, Dac; Tong, Ba Tuan; Giang Trinh, Thi; Tuong Pham, Van; Vu, Dinh Lam

    2016-12-01

    The research on magnetic resonances in typical meta-atoms has led to the discovery of electromagnetic metamaterials (MMs). These new materials played a crucial role in achieving extraordinary phenomena as well as promised potential applications. In this paper, we numerically and experimentally investigated two different MM effects: the absorption and the negative refraction, which induced by magnetic resonances in a symmetric structure. The meta-atom sandwich model that includes two parallel flat rings separated by an insulating slab was designed. Firstly, three resonances in sub-wavelength range were demonstrated, revealing the negative permittivity and permeability effects. Notably, negative refractive index (NRI) was gained at the third-gap resonance, resulting from superposition of the rest of the electric resonance and the magnetic one accompanied by multi-plasmon. Moreover, the manipulation of the structural parameters could control the NRI behavior and, interestingly, a nearly perfect absorption peak arises in shallow sub-wavelength regime.

  19. Exploring Electrical and Magnetic Resonances from Coherently Correlated Long-Lived Radical Pairs towards Development of Negative Refractive-Index Materials

    Science.gov (United States)

    2015-01-03

    Resonances from Coherently Correlated Long-Lived Radical Pairs towards Development of Negative Refractive - Index materials Grant/Contract Number AFOSR... Refractive - Index Materials Subtitle: Task 1: Radicals Based Molecular Metamaterials Task 2: Thin-Film Based Polymer Thermoelectric Devices 5a...and Magnetic Resonances from Coherently Correlated Long-Lived Radical Pairs towards Development of Negative - Index Materials Principle Investigator

  20. Properties of defect mode and optical enhancement of 1D photonic crystals with a defect layer of negative refractive index material

    Institute of Scientific and Technical Information of China (English)

    CHEN Xian-feng; SHEN Xiao-ming; JIANG Mei-ping; SHI Du-fang

    2005-01-01

    The band gap properties of one-dimensional photonic crystals with a defect layer of negative refractive index materials are studied.The defect mode width is bigger than that of conventional one-dimensional photonic crystals with a defect layer of positive refractive index materials.The defect mode of the former is different from that of the latter,shifts towards the direction of high frequency (short wavelength),and has a bigger shifting velocity.Furthermore the effects on the transmission properties of the former photonic crystals caused by change in the position of the defect layer of negative refractive index are investigated.Finally the optical enhancement of the former photonic crystals is also investigated.

  1. Circuit QED with hybrid metamaterial transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Ruloff, Stefan; Taketani, Bruno; Wilhelm, Frank [Theoretical Physics, Universitaet des Saarlandes, Saarbruecken (Germany)

    2016-07-01

    We're working on the theory of metamaterials providing some interesting results. The negative refraction index causes an opposite orientation of the wave vector k and the Poynting vector S of the travelling waves. Hence the metamaterial has a falling dispersion relation ∂ω(k)/∂k < 0 implying that low frequencies correspond to short wavelengths. Metamaterials are simulated by left-handed transmission lines consisting of discrete arrays of series capacitors and parallel inductors to ground. Unusual physics arises when right-and left-handed transmission lines are coupled forming a hybrid metamaterial transmission line. E.g. if a qubit is placed in front of a hybrid metamaterial transmission line terminated in an open circuit, the spontaneous emission rate is weakened or unaffected depending on the transition frequency of the qubit. Some other research interests are the general analysis of metamaterial cavities and the mode structure of hybrid metamaterial cavities for QND readout of multi-qubit operators. Especially the precise answer to the question about the definition of the mode volume of a metamaterial cavity is one of our primary goals.

  2. Fundamentals of negative refractive index optical trapping: forces and radiation pressures exerted by focused Gaussian beams using the generalized Lorenz-Mie theory.

    Science.gov (United States)

    Ambrosio, Leonardo A; Hernández-Figueroa, Hugo E

    2010-11-04

    Based on the generalized Lorenz-Mie theory (GLMT), this paper reveals, for the first time in the literature, the principal characteristics of the optical forces and radiation pressure cross-sections exerted on homogeneous, linear, isotropic and spherical hypothetical negative refractive index (NRI) particles under the influence of focused Gaussian beams in the Mie regime. Starting with ray optics considerations, the analysis is then extended through calculating the Mie coefficients and the beam-shape coefficients for incident focused Gaussian beams. Results reveal new and interesting trapping properties which are not observed for commonly positive refractive index particles and, in this way, new potential applications in biomedical optics can be devised.

  3. Design of omnidirectional and multiple channeled filters using one-dimensional photonic crystals containing a defect layer with a negative refractive index.

    Science.gov (United States)

    Xu, Kun-Yuan; Zheng, Xiguang; Li, Cai-Lian; She, Wei-Long

    2005-06-01

    The band structures of one-dimensional photonic crystals containing a defect layer with a negative refractive index are studied, showing that the defect modes possess three types of dispersion: positive, zero, and negative types. Based on these three types of dispersion, practical designs for large incident angle filters without polarization effect and for narrow frequency and sharp angular filters are suggested. Moreover, the splitting of one degenerate defect mode into multiple defect modes is observed in the band gap when the parameters of the defect layer vary. This mode splitting phenomenon can be used to design multiple channeled filters or filters with a rectangular profile. The dispersion multiplicity of the defect modes can be understood by an approximate formula, and the critical condition for the defect mode splitting is also analyzed. Based on these analyses, practical optimization design of omnidirectional filter is also suggested.

  4. Tailoring the negative-refractive-index metamaterials composed of semiconductor-metal-semiconductor gold ring/disk cavity heptamers to support strong Fano resonances in the visible spectrum.

    Science.gov (United States)

    Ahmadivand, Arash; Pala, Nezih

    2015-02-01

    In this study, we investigated numerically the plasmon response of a planar negative-index metamaterial composed of symmetric molecular orientations of Au ring/disk nanocavities in a heptamer cluster. Using the plasmon hybridization theory and considering the optical response of an individual nanocluster, we determined the accurate geometrical sizes for a ring/disk nanocavity heptamer. It is shown that the proposed well-organized nanocluster can be tailored to support strong and sharp Fano resonances in the visible spectrum. Surrounding and filling the heptamer clusters by various metasurfaces with different chemical characteristics, and illuminating the structure with an incident light source, we proved that this configuration reflects low losses and isotropic features, including a pronounced Fano dip in the visible spectrum. Technically, employing numerical methods and tuning the geometrical sizes of the structure, we tuned and induced the Fano dip in the visible range, while the dark and bright plasmon resonance extremes are blueshifted to shorter wavelengths dramatically. Considering the calculated transmission window, we quantified the effective refractive index for the structure, while the substance of the substrate material was varied. Using Si, GaP, and InP semiconductors as substrate materials, we calculated and compared the corresponding figure of merit (FOM) for different regimes. The highest possible FOM was obtained for the GaP-Au-GaP negative-refractive-index metamaterial composed of ring/disk nanocavity heptamers as 62.4 at λ∼690  nm (arounnd the position of the Fano dip). Despite the outstanding symmetric nature of the suggested heptamer array, we provided sharp Fano dips by the appropriate tuning of the geometrical and chemical parameters. This study yields a method to employ ring/disk nanocavity heptamers as a negative-refractive-index metamaterial in designing highly accurate localization of surface plasmon resonance sensing devices and

  5. Series Transmission Line Transformer

    Science.gov (United States)

    Buckles, Robert A.; Booth, Rex; Yen, Boris T.

    2004-06-29

    A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

  6. Electric Power Transmission Lines

    Data.gov (United States)

    Department of Homeland Security — Transmission Lines are the system of structures, wires, insulators and associated hardware that carry electric energy from one point to another in an electric power...

  7. Kansas Electric Transmission Lines

    Data.gov (United States)

    Kansas Data Access and Support Center — This data set is a digital representation of the EletcircTransmission lines for the State of Kansas as maintained by the Kansas Corporation Commission. Data is...

  8. Nonlinear magnetoinductive transmission lines

    CERN Document Server

    Lazarides, Nikos; Tsironis, G P

    2011-01-01

    Power transmission in one-dimensional nonlinear magnetic metamaterials driven at one end is investigated numerically and analytically in a wide frequency range. The nonlinear magnetic metamaterials are composed of varactor-loaded split-ring resonators which are coupled magnetically through their mutual inductances, forming thus a magnetoiductive transmission line. In the linear limit, significant power transmission along the array only appears for frequencies inside the linear magnetoinductive wave band. We present analytical, closed form solutions for the magnetoinductive waves transmitting the power in this regime, and their discrete frequency dispersion. When nonlinearity is important, more frequency bands with significant power transmission along the array may appear. In the equivalent circuit picture, the nonlinear magnetoiductive transmission line driven at one end by a relatively weak electromotive force, can be modeled by coupled resistive-inductive-capacitive (RLC) circuits with voltage-dependent cap...

  9. Conversion from constitutive parameters to dispersive transmission line parameters for multi-band metamaterials

    Science.gov (United States)

    Ozturk, Yusuf; Egemen Yilmaz, Asim; Ozbay, Ekmel

    2016-04-01

    In this study, we explain an approach including conversion from constitutive parameters to dispersive transmission line parameters using the double-band DNG (double-negative) properties of the circular type fishnet metamaterials. After designing the metamaterial structure, the numerical calculations and the composite right/left-handed (CRLH) modeling of circular-type metamaterials are realized in free space. Detailed dispersion characteristics give us the opportunity to explain the true behavior of the inclusions during the analysis stage. By combining the results coming from the standard retrieval procedure with the conventional CRLH theory, we calculate the actual values of the transmission line parameters for all frequency regimes. The constitutive parameters of an equivalent CRLH transmission line are derived and shown to be negative values. It is shown that the constitutive parameters present the same behavior for all negative refractive index regimes. The double-negative properties and the phase advance/lag behavior of metamaterials are observed based on the dispersive transmission line parameters.

  10. Optimizing Transmission Line Matching Circuits

    OpenAIRE

    Novak, S.

    1996-01-01

    When designing transmission line matching circuits, there exist often overlooked, additional, not much used, degree of choice in the selection of the transmission line impedance. In this work are presented results of CAD analysis for the two element transmission line matching networks, demonstrating that selecting matching circuits transmission lines with higher impedance, than usually used 50 or 75 ohms, can in most cases substantially decrease the physical dimension of the final matching ci...

  11. Negative refractive index in artificial metamaterials.

    Science.gov (United States)

    Grigorenko, A N

    2006-08-15

    We discuss optical constants in artificial metamaterials showing negative magnetic permeability and electric permittivity and suggest a simple formula for the refractive index of a general optical medium. Using the effective-field theory, we calculate the effective permeability and the refractive index of nanofabricated media composed of pairs of identical gold nanopillars with magnetic response in the visible spectrum.

  12. Studies on Negative Refractive Index without Absorption

    CERN Document Server

    Rajapakse, R M; Yelin, S F

    2012-01-01

    Which systems are ideal to obtain negative refraction with no absorption? Electromagnetically induced transparency (EIT) is a method to suppress absorption and make a material transparent to a field of a given frequency. Such a system has been discussed in [1]; however the main limitations for negative refraction introduced are the necessity of resonant electric and magnetic dipole transitions, and the necessity of very dense media. We suggest using frequency translators in a composite system that would provide negative refraction for a range of optical frequencies while attempting to overcome the limitations discussed above. In the process of using frequency translators, we also find composite systems that can be used for refractive index enhancement.

  13. Negative Refractive Index in Artificial Metamaterials

    OpenAIRE

    Grigorenko, A. N.

    2006-01-01

    We discuss optical constants in artificial metamaterials showing negative magnetic permeability and electric permittivity. Using effective field theory, we calculate effective permeability of nanofabricated media composed of pairs of identical gold nano-pillars with magnetic response in the visible spectrum.

  14. Negative Refractive Index Metasurfaces for Enhanced Biosensing

    Directory of Open Access Journals (Sweden)

    Dragan Tanasković

    2010-12-01

    Full Text Available In this paper we review some metasurfaces with negative values of effective refractive index, as scaffolds for a new generation of surface plasmon polariton-based biological or chemical sensors. The electromagnetic properties of a metasurface may be tuned by its full immersion into analyte, or by the adsorption of a thin layer on it, both of which change its properties as a plasmonic guide. We consider various simple forms of plasmonic crystals suitable for this purpose. We start with the basic case of a freestanding, electromagnetically symmetrical plasmonic slab and analyze different ultrathin, multilayer structures, to finally consider some two-dimensional “wallpaper” geometries like split ring resonator arrays and fishnet structures. A part of the text is dedicated to the possibility of multifunctionalization where a metasurface structure is simultaneously utilized both for sensing and for selectivity enhancement. Finally we give an overview of surface-bound intrinsic electromagnetic noise phenomena that limits the ultimate performance of a metasurfaces sensor.

  15. EC Transmission Line Materials

    Energy Technology Data Exchange (ETDEWEB)

    Bigelow, Tim S [ORNL

    2012-05-01

    The purpose of this document is to identify materials acceptable for use in the US ITER Project Office (USIPO)-supplied components for the ITER Electron cyclotron Heating and Current Drive (ECH&CD) transmission lines (TL), PBS-52. The source of material property information for design analysis shall be either the applicable structural code or the ITER Material Properties Handbook. In the case of conflict, the ITER Material Properties Handbook shall take precedence. Materials selection, and use, shall follow the guidelines established in the Materials Assessment Report (MAR). Materials exposed to vacuum shall conform to the ITER Vacuum Handbook. [Ref. 2] Commercial materials shall conform to the applicable standard (e.g., ASTM, JIS, DIN) for the definition of their grade, physical, chemical and electrical properties and related testing. All materials for which a suitable certification from the supplier is not available shall be tested to determine the relevant properties, as part of the procurement. A complete traceability of all the materials including welding materials shall be provided. Halogenated materials (example: insulating materials) shall be forbidden in areas served by the detritiation systems. Exceptions must be approved by the Tritium System and Safety Section Responsible Officers.

  16. Transmission line model for nanoelectronics

    Directory of Open Access Journals (Sweden)

    Nelin E. A.

    2009-08-01

    Full Text Available Analytical expressions for resonant parametres and characteristics of typical barrier nanoelectronic structures have been received on the basis of the transmission line model. Characteristics illustrating the efficiency of such approach are presented in the article.

  17. ac transmission line field measurements

    Energy Technology Data Exchange (ETDEWEB)

    Kotter, F.R.; Misakian, M.

    1977-11-01

    The concern in recent years over the environmental effects of electric and magnetic fields from high voltage transmission lines has also focused attention on the accuracy of measurements of these fields. Electric field meters are discussed in terms of theory of operation, parameters affecting performance, meter performance under field and laboratory conditions, and calibration procedures. The performance and calibration of magnetic field meters is described. (LCL)

  18. Coiled transmission line pulse generators

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, Kenneth Fox (Columbia, MO)

    2010-11-09

    Methods and apparatus are provided for fabricating and constructing solid dielectric "Coiled Transmission Line" pulse generators in radial or axial coiled geometries. The pour and cure fabrication process enables a wide variety of geometries and form factors. The volume between the conductors is filled with liquid blends of monomers, polymers, oligomers, and/or cross-linkers and dielectric powders; and then cured to form high field strength and high dielectric constant solid dielectric transmission lines that intrinsically produce ideal rectangular high voltage pulses when charged and switched into matched impedance loads. Voltage levels may be increased by Marx and/or Blumlein principles incorporating spark gap or, preferentially, solid state switches (such as optically triggered thyristors) which produce reliable, high repetition rate operation. Moreover, these Marxed pulse generators can be DC charged and do not require additional pulse forming circuitry, pulse forming lines, transformers, or an a high voltage spark gap output switch. The apparatus accommodates a wide range of voltages, impedances, pulse durations, pulse repetition rates, and duty cycles. The resulting mobile or flight platform friendly cylindrical geometric configuration is much more compact, light-weight, and robust than conventional linear geometries, or pulse generators constructed from conventional components. Installing additional circuitry may accommodate optional pulse shape improvements. The Coiled Transmission Lines can also be connected in parallel to decrease the impedance, or in series to increase the pulse length.

  19. Magnetically insulated transmission line oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Bacon, Larry D. (Albuquerque, NM); Ballard, William P. (Albuquerque, NM); Clark, M. Collins (Albuquerque, NM); Marder, Barry M. (Albuquerque, NM)

    1988-01-01

    A magnetically insulated transmission line oscillator employs self-generated magnetic fields to generate microwave energy. An anode of the oscillator includes slow-wave structures which are formed of a plurality of thin conductive vanes defining cavities therebetween, and a gap is formed between the anode and a cathode of the oscillator. In response to a pulsed voltage applied to the anode and cathode, self-generated magnetic fields arfe produced in a cross-field orientation with respect to the orientation of the electric field between the anode and the cathode. The cross-field magnetic fields insulate the flow of electrons in the gap and confine the flow of electrons within the gap.

  20. Frequency Selective Properties of Coaxial Transmission Lines Loaded with Combined Artificial Inclusions

    Directory of Open Access Journals (Sweden)

    Francisco Falcone

    2014-01-01

    Full Text Available The properties of a modified coaxial transmission line by periodic inclusions will be discussed. The introduction of split ring resonators, conductor stubs, air gaps, and combination of these gives rise to new frequency selective properties, such as stopband or passband behavior, observable in planar as well as volumetric metamaterial structures. These results envisage new potential applications and implementation of devices in coaxial transmission line technology.

  1. Transmission Line Security Monitor: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    John Svoboda

    2011-04-01

    The Electric Power Transmission Line Security Monitor System Operational Test is a project funded by the Technical Support Working Group (TSWG). TSWG operates under the Combating Terrorism Technical Support Office that functions under the Department of Defense. The Transmission Line Security Monitor System is based on technology developed by Idaho National Laboratory. The technology provides a means for real-time monitoring of physical threats and/or damage to electrical transmission line towers and conductors as well as providing operational parameters to transmission line operators to optimize transmission line operation. The end use is for monitoring long stretches of transmission lines that deliver electrical power from remote generating stations to cities and industry. These transmission lines are generally located in remote transmission line corridors where security infrastructure may not exist. Security and operational sensors in the sensor platform on the conductors take power from the transmission line and relay security and operational information to operations personnel hundreds of miles away without relying on existing infrastructure. Initiated on May 25, 2007, this project resulted in pre-production units tested in realistic operational environments during 2010. A technology licensee, Lindsey Manufacturing of Azusa California, is assisting in design, testing, and ultimately production. The platform was originally designed for a security monitoring mission, but it has been enhanced to include important operational features desired by electrical utilities.

  2. Overvoltage Suppression for UHV Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    LI Yongli; LIU Taihua; LI Zhongqing; JING Lei; LONG Ying; FAN Jianzhong

    2008-01-01

    The overvoltage phenomena of ultra high voltage (UHV) transmission lines are analyzed and verified by EMTDC/PSCAD simulation. Referring to the theoretical analyses and operating experiences of extra high voltage (EHV) transmission lines in China and UHV transmission lines in Russia and Japan, the methods to suppress the internal overvoltage in UHV transmission lines by protection and control strategies are discussed. Through the cooperation among the recloser, shunt reactor, tripping and closing resistance, and metal oxide varistor (MOV), the overvoltage can be restrained within an acceptable level.

  3. Omega Transmission Lines with Applications to Effective Medium Models of Metamaterials

    CERN Document Server

    Vehmas, Joni; Tretyakov, Sergei

    2014-01-01

    In this paper we introduce the concept of transmission lines with inherent bi-anisotropy and establish an analogy between these lines and volumetric bi-anisotropic materials. In particular, we find under what conditions a periodically loaded transmission line can be treated as an effective omega medium. Two example circuits are introduced and analyzed. The results have two-fold implications: opening a route to emulate electromagnetic properties of bi-anisotropic omega media using transmission-line meshes and understanding and improving effective medium models of composite materials with the use of effective circuit models of unit cells.

  4. Transmission Lines or Poles, Electric, electric transmission line, Published in unknown, Kleinschmidt.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset as of unknown. It is described as 'electric transmission line'. Data by this publisher are often provided in UTM...

  5. Pencil-Beam Single-point-fed Dirac Leaky-Wave Antenna on a Transmission-Line Grid

    CERN Document Server

    Dorrah, Ayman H

    2016-01-01

    Leaky-wave antennas (LWAs) are widely used as single-point-fed linear antenna arrays. The extension of LWAs to 2D implies that they can be used as single-point-fed 2D antenna arrays without requiring a complex feeding network. However, generating a pencil beam from 2D LWAs is not straightforward and due care has to be taken for the design of the LWA. On the other hand, transmission-line (TL) grids have demonstrated interesting behaviors, such as an effective negative refractive index and growing of evanescent waves. In this paper, a singlepoint-fed TL-grid 2D Dirac leaky-wave antenna (DLWA) design is proposed that generates a pencil beam at both broadside and slightly tilted angles. The TL-grid unit cell is analytically treated in light of its scattering and impedance matrices. The optimized TL-grid unit cell is shown to exhibit a closed bandgap in the dispersion relation which is also linearly varying with frequency (hence it is a DLWA). The proposed 2D DLWA design is fabricated and the experimental results ...

  6. TRANSMISSION LINE FAULT ANALYSIS USING WAVELET THEORY

    Directory of Open Access Journals (Sweden)

    Ravindra Malkar

    2012-06-01

    Full Text Available This paper describes a Wavelet transform technique to analyze power system disturbance such as transmission line faults with Biorthogonal and Haar wavelets. In this work, wavelet transform based approach,which is used to detect transmission line faults, is proposed. The coefficient of discrete approximation of the dyadic wavelet transform with different wavelets are used to be an index for transmission line fault detection and faulted – phase selection and select which wavelet is suitable for this application. MATLAB/Simulation is used to generate fault signals. Simulation results reveal that the performance of the proposed fault detection indicator is promising and easy to implement for computer relaying application.

  7. VT Electric Transmission Line Corridors - corridor lines

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The ELTRN layer depicts electric transmission line corridors in Vermont. Various methods have been used to digitize features. The data layer...

  8. Sevick's transmission line transformers theory and practice

    CERN Document Server

    Mack, Raymond

    2014-01-01

    An updated and reorganized revision of the classic book Transmission Line Transformers (2001) by Jerry Sevick, this book provides communication engineers with a clear technical presentation of both the theory and practical applications of the transmission of radio communication.

  9. VT Electric Transmission Line Corridors - substation points

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The ELTRN layer depicts electric transmission line corridors in Vermont. Various methods have been used to digitize features. The data layer...

  10. Transmission Line Resonator Segmented with Series Capacitors

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Boer, Vincent; Petersen, Esben Thade

    2016-01-01

    Transmission line resonators are often used as coils in high field MRI. Due to distributed nature of such resonators, coils based on them produce inhomogeneous field. This work investigates application of series capacitors to improve field homogeneity along the resonator. The equations for optimal...... values of evenly distributed capacitors are presented. The performances of the segmented resonator and a regular transmission line resonator are compared....

  11. Effective negative refractive index in ferromagnet-semiconductor superlattices.

    Science.gov (United States)

    Tarkanyan, Roland H; Niarchos, Dimitris G

    2006-06-12

    Problem of anomalous refraction of electromagnetic waves is analyzed in a superlattice which consists of alternating layers of ferromagnetic insulator and nonmagnetic semiconductor. Effective permittivity and permeability tensors are derived in the presence of an external magnetic field parallel to the plane of the layers. It is shown that in the case of the Voigt configuration, the structure behaves as a left-handed medium with respect to TE-type polarized wave, in the low-frequency region of propagation. The relative orientation of the Poynting vector and the refractive wave vector is examined in different frequency ranges. It is shown that the frequency region of existence for the backward mode can be changed using external magnetic field as tuning parameter.

  12. Negative refractive index metamaterials using only metallic cut wires.

    Science.gov (United States)

    Sellier, Alexandre; Burokur, Shah Nawaz; Kanté, Boubacar; de Lustrac, André

    2009-04-13

    We present, design and analyze a novel planar Left-Handed (LH) metamaterial at microwave frequencies. This metamaterial is composed of only metallic cut wires and is used under normal-to-plane incidence. Using Finite Element Method (FEM) based simulations and microwave experiments, we have investigated the material properties of the structure. Simultaneous negative values are observed for the permittivity epsilon and permeability mu by the inversion method from the transmission and reflection responses. A negative index n is verified in a bulk prism engineered by stacking several layers of the metamaterial. Our work demonstrates the feasibility of a LH metamaterial composed of only cut wires.

  13. Resolving the wave vector in negative refractive index media.

    Science.gov (United States)

    Ramakrishna, S Anantha; Martin, Olivier J F

    2005-10-01

    We address the general issue of resolving the wave vector in complex electromagnetic media including negative refractive media. This requires us to make a physical choice of the sign of a square root imposed merely by conditions of causality. By considering the analytic behavior of the wave vector in the complex plane, it is shown that there are a total of eight physically distinct cases in the four quadrants of two Riemann sheets.

  14. Reply to comment on "Negative refractive index in artificial metamaterials".

    Science.gov (United States)

    Grigorenko, A N

    2007-06-01

    The claims of the preceding Comment [Opt. Lett. 32, 1510 (2007)] are discussed. It is shown that Kildishev misread the previously presented method [Opt. Lett. 31, 2483 (2006)] for determining optical constants of nanostructured films. Reasons for a disagreement of the simulations presented in the Comment are also discussed.

  15. Chiral Swiss rolls show a negative refractive index.

    Science.gov (United States)

    Wiltshire, M C K; Pendry, J B; Hajnal, J V

    2009-07-22

    Chiral Swiss rolls, consisting of a metal/dielectric laminate tape helically wound on an insulating mandrel, have been developed to form the basis of a highly chiral metamaterial. We have fabricated these elements using a custom-built machine, and have characterized them. We find that the permeability, permittivity, and chirality are all resonant in the region of 80 MHz. The chirality is so strong that it can be directly measured by observing the magnetic response to an applied electric field, and is larger than either the permeability or the permittivity. We have estimated the refractive indices from these data, and find both strong circular dichroism and a wide frequency range where the refractive index is negative.

  16. Octonacci photonic crystals with negative refraction index materials

    Science.gov (United States)

    Brandão, E. R.; Vasconcelos, M. S.; Anselmo, D. H. A. L.

    2016-12-01

    We investigate the optical transmission spectra for s-polarized (TE) and p-polarized (TM) waves in one-dimensional photonic quasicrystals on a quasiperiodic multilayer structure made up by alternate layers of SiO2 and metamaterials, organized by following the Octonacci sequence. Maxwell's equations and the transfer-matrix technique are used to derive the transmission spectra for the propagation of normally and obliquely incident optical fields. We assume Drude-Lorentz-type dispersive response for the dielectric permittivity and magnetic permeability of the metamaterials. For normally incident waves, we observe that the spectra does not have self-similar behavior or mirror symmetry and it also features the absence of optical band gap. Also for normally incident waves, we show regions of full transmittance when the incident angle θC = 0° in a particular frequency range.

  17. Octonacci Photonic Crystals with Negative Refraction Index Materials

    CERN Document Server

    Brandao, E R; Anselmo, D H A L

    2016-01-01

    We investigate the optical transmission spectra for $s$-polarized (TE) and $p$-polarized (TM) waves in one-dimensional photonic quasicrystals on a quasiperiodic multilayer structure made up by alternate layers of SiO$_{2}$ and \\textit{metamaterials}, organized by following the Octonacci sequence. Maxwell's equations and the transfer-matrix technique are used to derive the transmission spectra for the propagation of normaly and obliquely incident optical fields. We assume Drude-Lorentz-type dispersive response for the dielectric permittivity and magnetic permeability of the metamaterials. For normally incident waves, we observe that the spectra does not have self-similar behavior or mirror symmetry and it also features the absence of optical band gap. Also for normally incident waves, we show regions of full transmittance when the incident angle $\\theta_{C} = 0^{\\circ}$ in a particular frequency range.

  18. Textile inspired flexible metamaterial with negative refractive index

    Science.gov (United States)

    Burgnies, L.; Lheurette, É.; Lippens, D.

    2015-04-01

    This work introduces metallo-dielectric woven fabric as a metamaterial for phase-front manipulation. Dispersion diagram as well as effective medium parameters retrieved from reflection and transmission coefficients point out negative values of refractive index. By numerical simulations, it is evidenced that a pair of meandered metallic wires, arranged in a top to bottom configuration, can yield to a textile metamaterial with simultaneously negative permittivity and permeability. While the effective negative permittivity stems from the metallic grid arrangement, resonating current loop resulting from the top to bottom configuration of two meandered metallic wires in near proximity produces magnetic activity with negative permeability. By adjusting the distance between pairs of metallic wires, the electric plasma frequency can be shifted to overlap the magnetic resonance. Finally, it is shown that the woven metamaterial is insensitive to the incident angle up to around 60°.

  19. Transmission Line Adapted Analytical Power Charts Solution

    Science.gov (United States)

    Sakala, Japhet D.; Daka, James S. J.; Setlhaolo, Ditiro; Malichi, Alec Pulu

    2016-08-01

    The performance of a transmission line has been assessed over the years using power charts. These are graphical representations, drawn to scale, of the equations that describe the performance of transmission lines. Various quantities that describe the performance, such as sending end voltage, sending end power and compensation to give zero voltage regulation, may be deduced from the power charts. Usually required values are read off and then converted using the appropriate scales and known relationships. In this paper, the authors revisit this area of circle diagrams for transmission line performance. The work presented here formulates the mathematical model that analyses the transmission line performance from the power charts relationships and then uses them to calculate the transmission line performance. In this proposed approach, it is not necessary to draw the power charts for the solution. However the power charts may be drawn for the visual presentation. The method is based on applying derived equations and is simple to use since it does not require rigorous derivations.

  20. Composite Based EHV AC Overhead Transmission Lines

    DEFF Research Database (Denmark)

    Sørensen, Thomas Kjærsgaard

    Overhead lines at transmission level are the backbone of any national power grid today. New overhead line projects however are at the same time subject to ever greater public resistance due to the lines environmental impact. As full undergrounding of transmission lines at extra high voltage (EHV...... and analysed with regard to the possibilities, limitations and risks widespread application of composite materials on EHV AC overhead transmission lines may present. To form the basis for evaluation of the useability of composite materials, dierent overhead line projects aimed at reducing the environmental...

  1. Electromagnetic analysis using transmission line variables

    CERN Document Server

    Weiner, Maurice

    2010-01-01

    This book employs a relatively new method for solving electromagnetic problems, one which makes use of a transmission line matrix (TLM). The propagation space is imagined to be filled with this matrix. The propagating fields and physical properties are then mapped onto the matrix. Mathematically, the procedures are identical with the traditional numerical methods; however, the interpretation and physical appeal of the transmission line matrix are far superior. Any change in the matrix has an immediate physical significance. What is also very important is that the matrix becomes a launching pad

  2. Concurrent Wind Cooling in Power Transmission Lines

    Energy Technology Data Exchange (ETDEWEB)

    Jake P Gentle

    2012-08-01

    Idaho National Laboratory and the Idaho Power Company, with collaboration from Idaho State University, have been working on a project to monitor wind and other environmental data parameters along certain electrical transmission corridors. The combination of both real-time historical weather and environmental data is being used to model, validate, and recommend possibilities for dynamic operations of the transmission lines for power and energy carrying capacity. The planned results can also be used to influence decisions about proposed design criteria for or upgrades to certain sections of the transmission lines.

  3. Artificial Dielectric Shields for Integrated Transmission Lines

    NARCIS (Netherlands)

    Ma, Y.; Rejaei, B.; Zhuang, Y.

    2008-01-01

    We present a novel shielding method for on-chip transmission lines built on conductive silicon substrates. The shield consists of an artificial dielectric with a very high in-plane dielectric constant, built from two patterned metal layers isolated by a very thin dielectric film. Inserted below an i

  4. Conceptual design for transmission line inspection robot

    Science.gov (United States)

    Jalal, M. F. Abdul; Sahari, K. S. Mohamed; Anuar, A.; Mohd Arshad, A. D.; Idris, M. S.

    2013-06-01

    Power transmission line is used for power distribution purposes due to their cost effective measure compared to underlying cable. However, prolonged exposure to natural weather may cause fatigue stress to the lines as well as induce material failure. Therefore, periodical line inspection is considered uttermost important as a preventive measure to avoid power outage. However, transmission line inspection has always been a high risk and expensive work. Hazardous works that may harm operator as well as routine that requires precise handling can be performed by robots. Various types of robots have been designed and developed for line inspection but only perform well on a straight and continuous line. As these robots encounter an obstacle during the inspection, then the real problem in terms of robot stability and smooth operation arises. In this paper, conceptual design and evaluation for transmission line inspection robot is presented. The inspection robot mobile robot must be able to bypass or avoid obstacles as it travels along the power transmission line.

  5. Microwave transmission-line impedance data

    CERN Document Server

    Gunston, M A R

    1996-01-01

    A compendium of data for computing the characteristic impedance of transmission lines based on physical dimensions. Covers both conventional structures and unusual geometries, including coaxial, eccentric and elliptic coaxial, twin-wire, wire-above-ground, microstrip and derivatives, stripline, slabline and trough line. Also details numerous configurations of coupled lines.

  6. Tornado risk model for transmission line design

    CSIR Research Space (South Africa)

    Milford, RV

    1997-11-01

    Full Text Available is in combination with ice loading. The wind load used in most codes of practice and design recommendations for transmission line design have until recently been based almost exclusively on large-scale wind storms, which may include severe storms such as hurricanes...

  7. 18 CFR 2.2 - Transmission lines.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Transmission lines. 2.2 Section 2.2 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES GENERAL POLICY AND INTERPRETATIONS Statements of General Policy and...

  8. 49 CFR 192.706 - Transmission lines: Leakage surveys.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Leakage surveys. 192.706... Transmission lines: Leakage surveys. Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year. However, in the case of a transmission line...

  9. PROPAGATION CHARACTERISTICS OF ELECTROMAGNETIC WAVES IN GRADIENT TRANSMISSION LINE

    OpenAIRE

    Nesterov Iurii Gavriilovitch; Silin Nikolay Vitalievich

    2015-01-01

    Propagation characteristics of transmission lines with smooth continuous spatial distribution of capacitance and inductance (gradient transmission line) is considered in the framework of recently developed mathematical model. Strong heterogeneity-induced artificial dispersion is described by means of this model. Reflectance and transmittance spectra are shown on example of different gradient transmission lines. In conclusion, applicability of gradient transmission lines in areas o...

  10. Flux qubit to a transmission line

    Energy Technology Data Exchange (ETDEWEB)

    Haeberlein, Max; Baust, Alexander; Zhong, Ling; Gross, Rudolf [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, TU Muenchen, Garching (Germany); Nanosystems Initiative Munich (NIM), Muenchen (Germany); Anderson, Gustav; Wang, Lujun; Eder, Peter; Fischer, Michael; Goetz, Jan; Xie, Edwar; Schwarz, Manuel; Wulschner, Karl Friedrich; Deppe, Frank; Fedorov, Kirill; Huebl, Hans; Menzel, Edwin [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, TU Muenchen, Garching (Germany); Marx, Achim [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany)

    2015-07-01

    Within the last decade, superconducting qubits coupled to microwave resonators have been extensively studied within the framework of quantum electrodynamics. Ultimately, quantum computing seems within reach in such architectures. However, error correction schemes are necessary to achieve the required fidelity in multi-qubit operations, drastically increasing the number of qubits involved. In this work, we couple a flux qubit to a transmission line where it interacts with itinerant microwave photons granting access to all-optical quantum computing. In this approach, travelling photons generate entanglement between two waveguides, containing the qubit information. In this presentation, we show experimental data on flux qubits coupled to transmission lines. Furthermore, we will discuss entanglement generation between two separate paths.

  11. Self-Shielding Of Transmission Lines

    Energy Technology Data Exchange (ETDEWEB)

    Christodoulou, Christos [Univ. of New Mexico, Albuquerque, NM (United States)

    2017-03-01

    The use of shielding to contend with noise or harmful EMI/EMR energy is not a new concept. An inevitable trade that must be made for shielding is physical space and weight. Space was often not as much of a painful design trade in older larger systems as they are in today’s smaller systems. Today we are packing in an exponentially growing number of functionality within the same or smaller volumes. As systems become smaller and space within systems become more restricted, the implementation of shielding becomes more problematic. Often, space that was used to design a more mechanically robust component must be used for shielding. As the system gets smaller and space is at more of a premium, the trades starts to result in defects, designs with inadequate margin in other performance areas, and designs that are sensitive to manufacturing variability. With these challenges in mind, it would be ideal to maximize attenuation of harmful fields as they inevitably couple onto transmission lines without the use of traditional shielding. Dr. Tom Van Doren proposed a design concept for transmission lines to a class of engineers while visiting New Mexico. This design concept works by maximizing Electric field (E) and Magnetic Field (H) field containment between operating transmission lines to achieve what he called “Self-Shielding”. By making the geometric centroid of the outgoing current coincident with the return current, maximum field containment is achieved. The reciprocal should be true as well, resulting in greater attenuation of incident fields. Figure’s 1(a)-1(b) are examples of designs where the current centroids are coincident. Coax cables are good examples of transmission lines with co-located centroids but they demonstrate excellent field attenuation for other reasons and can’t be used to test this design concept. Figure 1(b) is a flex circuit design that demonstrate the implementation of self-shielding vs a standard conductor layout.

  12. ULTRA HIGH POWER TRANSMISSION LINE TECHNIQUES

    Science.gov (United States)

    The ultra-high power transmission line techniques including both failure mechanisms and component design are discussed. Failures resulting from...a waveguide. In view of the many advantages of the low loss mode in circular waveguide for ultra-high power levels, a mode transducer and a two...percent of the peak power of a standard rectangular wave guide. Water cooling is provided for high average power operation. Analysis of mode sup pression

  13. Resonant Transmission Line Method for Econophysics models

    CERN Document Server

    Raptis, T E

    2016-01-01

    In a recent paper [1304.6846], Racorean introduced a formal similarity of the Black-Sholes stock pricing model with a Schr\\"odinger equation. We use a previously introduced method of a resonant transmission line for arbitrary 2nd order Sturm-Liouville problems to attack the same problem from a different perspective revealing some deep structures in the naturally associated eigenvalue problem.

  14. Conditions of the Classical Transmission Line Equations at High Frequency

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    New transmission line equations are deduced applying Maxwell's equations in this paper. The conditions of the classical transmission line equations have been discussed, which is important to solve the EM problems in high frequency case.

  15. Robust hyperchaotic synchronization via analog transmission line

    Science.gov (United States)

    Sadoudi, S.; Tanougast, C.

    2016-02-01

    In this paper, a novel experimental chaotic synchronization technique via analog transmission is discussed. We demonstrate through Field-Programmable Gate Array (FPGA) implementation design the robust synchronization of two embedded hyperchaotic Lorenz generators interconnected with an analog transmission line. The basic idea of this work consists in combining a numerical generation of chaos and transmitting it with an analog signal. The numerical chaos allows to overcome the callback parameter mismatch problem and the analog transmission offers robust data security. As application, this technique can be applied to all families of chaotic systems including time-delayed chaotic systems.

  16. Transient Stability Analysis Using Transmission Line Measurement

    Institute of Scientific and Technical Information of China (English)

    蔡国伟; 程浩忠; 陈家荣; 王承民

    2004-01-01

    The novel quantitative assessment method using transmission line measurement was developed. A new style of stability criterion was suggested which is based on the line measurement. The stability indices for lines,cutsets and power system according to features of transient energy in the lines were given, which not only provide a reliable and accurate assessment of the transient stability of power system, but also can be used to assess the effect of lines and cutsets on the transient stability and identify the weak transmission segment. Examples were presented by simulation on the IEEE-39 buses test system.

  17. PSpice for filters and transmission lines

    CERN Document Server

    Tobin, Paul

    2007-01-01

    In this book, PSpice for Filters and Transmission Lines, we examine a range of active and passive filters where each design is simulated using the latest Cadence Orcad V10.5 PSpice capture software. These filters cannot match the very high order digital signal processing (DSP) filters considered in PSpice for Digital Signal Processing, but nevertheless these filters have many uses. The active filters considered were designed using Butterworth and Chebychev approximation loss functions rather than using the 'cookbook approach' so that the final design will meet a given specification in an exact

  18. Ultrafast response of superconducting transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Chwalek, J.M.; Dykaar, D.R.; Whitaker, J.F.; Sobolewski, R.; Grupta, S.; Hsiang, T.Y.; Mourou, G.A.

    1989-03-01

    The authors report investigations of picosecond transient propagation on normal and superconducting transmission lines and new results for a variety of lines that include YBa/sub 2/Cu/sub 3/O/sub 7-x/ (YBCO) coplanar lines, a superconducting coaxial cable, and a dielectric-matched gold-line structure. A previously developed algorithm for analyzing transient propagation was used to identify the dominant mechanisms for signal distortion in most of these cases, and the essential properties of all lines tested to date are summarized for a direct comparison.

  19. Discontinuity effects on radial cavity transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Seidel, D.B.

    1979-04-01

    Pulse propagation in radial cavity transmission lines such as those found on a radial line accelerator is considered. Specifically, the effects of discontinuities along the line are examined in detail. It is found that previous analyses of such effects have been incorrect, and here two alternate solution techniques are presented. Depending upon the parameters of such a radial line, the discontinuity effects considered here may or may not be significant; however, if they are significant, it is recommended that the alternate solution techniques presented here be used.

  20. 49 CFR 192.719 - Transmission lines: Testing of repairs.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Testing of repairs. 192.719... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.719 Transmission lines: Testing of repairs. (a) Testing of replacement pipe. If a segment of transmission line...

  1. 49 CFR 192.745 - Valve maintenance: Transmission lines.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Valve maintenance: Transmission lines. 192.745... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.745 Valve maintenance: Transmission lines. (a) Each transmission line valve that might be required during any...

  2. A radial transmission line material measurement apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Warne, L.K.; Moyer, R.D.; Koontz, T.E.; Morris, M.E.

    1993-05-01

    A radial transmission line material measurement sample apparatus (sample holder, offset short standards, measurement software, and instrumentation) is described which has been proposed, analyzed, designed, constructed, and tested. The purpose of the apparatus is to obtain accurate surface impedance measurements of lossy, possibly anisotropic, samples at low and intermediate frequencies (vhf and low uhf). The samples typically take the form of sections of the material coatings on conducting objects. Such measurements thus provide the key input data for predictive numerical scattering codes. Prediction of the sample surface impedance from the coaxial input impedance measurement is carried out by two techniques. The first is an analytical model for the coaxial-to-radial transmission line junction. The second is an empirical determination of the bilinear transformation model of the junction by the measurement of three full standards. The standards take the form of three offset shorts (and an additional lossy Salisbury load), which have also been constructed. The accuracy achievable with the device appears to be near one percent.

  3. Geotechnical assessments of upgrading power transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Andrew [Coffey Geotechnics Ltd., Harrogate (United Kingdom)

    2012-11-01

    One of the consequences of increasing demand for energy is a corresponding requirement for increased energy distribution. This trend is likely to be magnified by the current tendency to generate power in locations remote from centres of population. New power transmission routes are expensive and awkward to develop, and there are therefore benefits to be gained by upgrading existing routes. However, this in turn raises problems of a different nature. The re-use of any structure must necessarily imply the acceptance of unknowns. The upgrading of transmission lines is no exception to this, particularly when assessing foundations, which in their nature are not visible. A risk-based approach is therefore used. This paper describes some of the geotechnical aspects of the assessment of electric power transmission lines for upgrading. It briefly describes the background, then discusses some of the problems encountered and the methods used to address them. These methods are based mainly on information obtained from desk studies and walkover surveys, with a limited amount of intrusive investigation. (orig.)

  4. Analysis and application of transmission line conductors

    Science.gov (United States)

    Laney, Orin

    Skin effect is usually a concern reserved for radio frequency design and for high current conductors used in utility power distribution. Proximity effect between adjacent conductors has traditionally been a concern for the design of magnetic windings and other applications involving wire bundles. The rise in the ubiquity of high speed bit streams and other signals of very wide bandwidth has broadened the range of applicable contexts and increased the need to account for such effects. This is especially true for transmission lines used to interconnect critical signal paths in applications ranging from microelectronic devices to the signal integrity of printed circuit traces and implementation of system cabling. Optimal conductor design is obviously fundamental to transmission line performance. Researchers have paid considerable attention to the topic but the results are scattered throughout the literature. This thesis collected information on extant conductor designs, and the theoretical considerations behind each solution. A detailed analysis of current flow in a conducting half-space was included as a foundation. The conductor types discussed were solid cylindrical, rectangular, ribbonoid, bimetallic, tubular, laminated, litz, and stranded constructions. Discussions of the performance of stranded shields and conductor roughness e¤ects were included for completeness of understanding.

  5. Modeling Transmission Line Networks Using Quantum Graphs

    Science.gov (United States)

    Koch, Trystan; Antonsen, Thomas

    Quantum graphs--one dimensional edges, connecting nodes, that support propagating Schrödinger wavefunctions--have been studied extensively as tractable models of wave chaotic behavior (Smilansky and Gnutzmann 2006, Berkolaiko and Kuchment 2013). Here we consider the electrical analog, in which the graph represents an electrical network where the edges are transmission lines (Hul et. al. 2004) and the nodes contain either discrete circuit elements or intricate circuit elements best represented by arbitrary scattering matrices. Including these extra degrees of freedom at the nodes leads to phenomena that do not arise in simpler graph models. We investigate the properties of eigenfrequencies and eigenfunctions on these graphs, and relate these to the statistical description of voltages on the transmission lines when driving the network externally. The study of electromagnetic compatibility, the effect of external radiation on complicated systems with numerous interconnected cables, motivates our research into this extension of the graph model. Work supported by the Office of Naval Research (N0014130474) and the Air Force Office of Scientific Research.

  6. Dispersion-free radial transmission lines

    Science.gov (United States)

    Caporaso, George J [Livermore, CA; Nelson, Scott D [Patterson, CA

    2011-04-12

    A dispersion-free radial transmission line ("DFRTL") preferably for linear accelerators, having two plane conductors each with a central hole, and an electromagnetically permeable material ("EPM") between the two conductors and surrounding a channel connecting the two holes. At least one of the material parameters of relative magnetic permeability, relative dielectric permittivity, and axial width of the EPM is varied as a function of radius, so that the characteristic impedance of the DFRTL is held substantially constant, and pulse transmission therethrough is substantially dispersion-free. Preferably, the EPM is divided into concentric radial sections, with the varied material parameters held constant in each respective section but stepwise varied between sections as a step function of the radius. The radial widths of the concentric sections are selected so that pulse traversal time across each section is the same, and the varied material parameters of the concentric sections are selected to minimize traversal error.

  7. Multi-transmission-line-beam interactive system

    Energy Technology Data Exchange (ETDEWEB)

    Figotin, Alexander; Reyes, Guillermo [Department of Mathematics, University of California at Irvine, Irvine, California 92697-3875 (United States)

    2013-11-15

    We construct here a Lagrangian field formulation for a system consisting of an electron beam interacting with a slow-wave structure modeled by a possibly non-uniform multiple transmission line (MTL). In the case of a single line we recover the linear model of a traveling wave tube due to J. R. Pierce. Since a properly chosen MTL can approximate a real waveguide structure with any desired accuracy, the proposed model can be used in particular for design optimization. Furthermore, the Lagrangian formulation provides: (i) a clear identification of the mathematical source of amplification, (ii) exact expressions for the conserved energy and its flux distributions obtained from the Noether theorem. In the case of uniform MTLs we carry out an exhaustive analysis of eigenmodes and find sharp conditions on the parameters of the system to provide for amplifying regimes.

  8. Characterization of superconducting transmission line resonators

    Energy Technology Data Exchange (ETDEWEB)

    Goetz, Jan; Summer, Philipp; Meier, Sebastian; Haeberlein, Max; Wulschner, Karl Friedrich; Eder, Peter; Fischer, Michael; Schwarz, Manuel; Deppe, Frank; Fedorov, Kirill; Huebl, Hans; Menzel, Edwin [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, TU Muenchen, Garching (Germany); Krawczyk, Marta; Marx, Achim [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Baust, Alexander; Xie, Edwar; Zhong, Ling; Gross, Rudolf [Walther-Meissner-Institut, Bayerische Akademie der Wissenschaften, Garching (Germany); Physik-Department, TU Muenchen, Garching (Germany); Nanosystems Initiative Munich (NIM), Muenchen (Germany)

    2015-07-01

    Superconducting transmission line resonators are widely used in circuit quantum electrodynamics experiments as quantum bus or storage devices. For these applications, long coherence times, which can be linked to the internal quality factor of the resonators, are crucial. Here, we show a systematic study of the internal quality factor of niobium thin film resonators. We analyze different cleaning methods and substrate parameters for coplanar waveguide as well as microstrip geometries. In addition, we investigate the impact of a niobium-aluminum interface which is necessary for galvanically coupled flux qubits made from aluminum. This interface can be avoided by fabricating the complete resonator-qubit structure using Al/AlO{sub x}/Al technology during fabrication.

  9. Thermal Rectification in Graded Nonlinear Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    许文; 陈伟中; 陶锋

    2011-01-01

    We consider heat conduction in a nonlinear inductance-capacitance(LC)transmission line with an inductance gradient by adding white-noise signals.It is found that the heat flux in the direction of inductance decrease is larger than that in the direction of inductance increase.When the low-inductance end is at higher temperature,the phonon density decreases due to conversion to high-frequency phonons,which can not move to the high-inductance end due to its lower cutoff frequency.However,when the high-inductance end is at higher temperature,the loss of phonon density can be compensated for because some high-frequency phonons can move to the low-inductance end dur to its higher cutoff frequency.This leads to the asymmetry of energy transfer.Discussion shows that this asymmetry exists in a particular range of temperatures,and increases with the increase of the difference between heat baths and the inductance gradient.%We consider heat conduction in a nonlinear inductance-capacitance (LC) transmission line with an inductance gradient by adding white-noise signals. It is found that the heat flux in the direction of inductance decrease is larger than that in the direction of inductance increase. When the low-inductance end is at higher temperature, the phonon density decreases due to conversion to high-frequency phonons, which can not move to the high-inductance end due to its lower cutoff frequency. However, when the high-inductance end is at higher temperature, the loss of phonon density can be compensated for because some high-frequency phonons can move to the low-inductance end dur to its higher cutoff frequency. This leads to the asymmetry of energy transfer. Discussion shows that this asymmetry exists in a particular range of temperatures, and increases with the increase of the difference between heat baths and the inductance gradient.

  10. The Transmission Line for the SPIDER experiment

    Energy Technology Data Exchange (ETDEWEB)

    Boldrin, Marco, E-mail: marco.boldrin@igi.cnr.it [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); De Lorenzi, Antonio; Recchia, Mauro; Toigo, Vanni [Consorzio RFX, Associazione EURATOM-ENEA sulla Fusione, Corso Stati Uniti 4, I-35127 Padova (Italy); Bonicelli, Tullio; Simon, Muriel [Fusion For Energy, c/o Josep Pla 2, 08019 Barcelona (Spain)

    2011-10-15

    The 100 keV Ion Source Test facility - Source for the Production of Ions of Deuterium Extracted from RF plasma (SPIDER) - is aimed to test the full scale prototype of the Ion Source for the ITER 1 MeV Neutral Beam Injector (NBI). The SPIDER facility requires the construction of a High Voltage Deck (HVD) and of a High Voltage Transmission Line (TL) respectively to host the Ion Source Power Supplies system polarized at 100 kV and to carry the power and signal conductors to the beam accelerator. In already existing NBI systems with beam energy above 100 keV, the TL is realized with the SF{sub 6} Gas Insulated Line technology. In the SPIDER TL case, the presence of a large inner conductor (half meter diameter), would make the pressurized TL a complex and costly component; therefore a free air insulated solution has been proposed. The paper focuses on the design of this TL, which has to host inside the complex high potential (100 kV) inner electrode a number of power and measuring conductors and has to minimize the Electro Magnetic Interferences (EMI) produced by the frequent grids breakdowns. Finite Element (FE) analyses have been performed to verify the configuration from the electrostatic point of view, to evaluate EMI screening effectiveness and to assess the impact of the relatively high thermal dissipation of power conductors located inside the high potential electrode. Moreover, an experimental test campaign has been carried out on a TL mockup to validate the TL electrostatic configuration under DC voltage. Finally, the paper reports on the status of procurement activities for the Transmission Line.

  11. Investigation of a stripline transmission line structure for gyromagnetic nonlinear transmission line high power microwave sources.

    Science.gov (United States)

    Reale, D V; Parson, J M; Neuber, A A; Dickens, J C; Mankowski, J J

    2016-03-01

    A stripline gyromagnetic nonlinear transmission line (NLTL) was constructed out of yttrium iron garnet ferrite and tested at charge voltages of 35 kV-55 kV with bias fields ranging from 10 kA/m to 20 kA/m. Typically, high power gyromagnetic NLTLs are constructed in a coaxial geometry. While this approach has many advantages, including a uniform transverse electromagnetic (TEM) mode, simple interconnection between components, and the ability to use oil or pressurized gas as an insulator, the coaxial implementation suffers from complexity of construction, especially when using a solid insulator. By moving to a simpler transmission line geometry, NLTLs can be constructed more easily and arrayed on a single substrate. This work represents a first step in exploring the suitability of various transmission line structures, such as microstrips and coplanar waveguides. The resulting high power microwave (HPM) source operates in ultra high frequency (UHF) band with an average bandwidth of 40.1% and peak rf power from 2 MW to 12.7 MW.

  12. Transmission line sag calculations using interval mathematics

    Energy Technology Data Exchange (ETDEWEB)

    Shaalan, H. [Institute of Electrical and Electronics Engineers, Washington, DC (United States)]|[US Merchant Marine Academy, Kings Point, NY (United States)

    2007-07-01

    Electric utilities are facing the need for additional generating capacity, new transmission systems and more efficient use of existing resources. As such, there are several uncertainties associated with utility decisions. These uncertainties include future load growth, construction times and costs, and performance of new resources. Regulatory and economic environments also present uncertainties. Uncertainty can be modeled based on a probabilistic approach where probability distributions for all of the uncertainties are assumed. Another approach to modeling uncertainty is referred to as unknown but bounded. In this approach, the upper and lower bounds on the uncertainties are assumed without probability distributions. Interval mathematics is a tool for the practical use and extension of the unknown but bounded concept. In this study, the calculation of transmission line sag was used as an example to demonstrate the use of interval mathematics. The objective was to determine the change in cable length, based on a fixed span and an interval of cable sag values for a range of temperatures. The resulting change in cable length was an interval corresponding to the interval of cable sag values. It was shown that there is a small change in conductor length due to variation in sag based on the temperature ranges used in this study. 8 refs.

  13. Modelling lightning caused transmission line outages in Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Wu, M.; Shen, S.S.P. [Alberta Univ., Edmonton, AB (Canada). Dept. of Mathematical and Statistical Sciences; Koval, D.O. [Alberta Univ., Edmonton, AB (Canada). Dept. of Electrical Engineering

    2005-07-01

    The characteristics of lightning and the relationship between lightning and transmission line outages is not fully understood by utility planners. This study used 20 year data sets of lightning events to investigate the spatial and temporal patterns of lightning in Alberta. Studies of geographical and temporal characteristics of lightning caused transmission line outages for several voltage level transmission lines were also examined. A lasso regression variable selection procedure and Cp criterion were used to model the duration of the lightning-caused transmission line outages as a function of weather and lightning patterns. The province was divided into 110 by 110 grids, and lightning variables were calculated for each cell. All the lightning variables for each cell were then averaged based on their areas. The overall cloud-ground lightning flashes 20-year mean frequency and the physical locations of power transmission lines were then plotted. Estimated probability density functions of the duration of lightning caused transmission line outages were classified by their voltage levels. The study showed that the characteristics of the lightning caused outages were different for different voltage levels of the transmission lines. Results suggested that the findings will have a significant impact on the accuracy of reliability methodologies that use the average duration of transmission line outages in their calculations. It was concluded that the new methodology can be applied to any transmission line system operating in a unique geographical environmental area. 11 refs., 3 tabs., 5 figs.

  14. Wind adaptive modeling of transmission lines using minimum description length

    Science.gov (United States)

    Jaw, Yoonseok; Sohn, Gunho

    2017-03-01

    The transmission lines are moving objects, which positions are dynamically affected by wind-induced conductor motion while they are acquired by airborne laser scanners. This wind effect results in a noisy distribution of laser points, which often hinders accurate representation of transmission lines and thus, leads to various types of modeling errors. This paper presents a new method for complete 3D transmission line model reconstruction in the framework of inner and across span analysis. The highlighted fact is that the proposed method is capable of indirectly estimating noise scales, which corrupts the quality of laser observations affected by different wind speeds through a linear regression analysis. In the inner span analysis, individual transmission line models of each span are evaluated based on the Minimum Description Length theory and erroneous transmission line segments are subsequently replaced by precise transmission line models with wind-adaptive noise scale estimated. In the subsequent step of across span analysis, detecting the precise start and end positions of the transmission line models, known as the Point of Attachment, is the key issue for correcting partial modeling errors, as well as refining transmission line models. Finally, the geometric and topological completion of transmission line models are achieved over the entire network. A performance evaluation was conducted over 138.5 km long corridor data. In a modest wind condition, the results demonstrates that the proposed method can improve the accuracy of non-wind-adaptive initial models on an average of 48% success rate to produce complete transmission line models in the range between 85% and 99.5% with the positional accuracy of 9.55 cm transmission line models and 28 cm Point of Attachment in the root-mean-square error.

  15. 7 CFR 1726.77 - Substation and transmission line construction.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Substation and transmission line construction. 1726... UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE ELECTRIC SYSTEM CONSTRUCTION POLICIES AND PROCEDURES Substation and Transmission Facilities § 1726.77 Substation and transmission line construction. (a) Contract...

  16. 49 CFR 192.705 - Transmission lines: Patrolling.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Patrolling. 192.705 Section... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.705 Transmission... adjacent to the transmission line right-of-way for indications of leaks, construction activity, and...

  17. 49 CFR 192.709 - Transmission lines: Record keeping.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Record keeping. 192.709... TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.709 Transmission lines: Record keeping. Each operator shall maintain the following records for transmission...

  18. 32 CFR 644.431 - Power transmission lines.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Power transmission lines. 644.431 Section 644.431... ESTATE HANDBOOK Disposal Disposal of Fee-Owned Real Property and Easement Interests § 644.431 Power transmission lines. (a) Authority. Pursuant to the provisions of section 13(d) of the Surplus Property Act...

  19. 49 CFR 192.179 - Transmission line valves.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission line valves. 192.179 Section 192.179... line valves. (a) Each transmission line, other than offshore segments, must have sectionalizing block valves spaced as follows, unless in a particular case the Administrator finds that alternative...

  20. Survey of transmission line corridors. [Data on delays in transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-05

    The intent of this study is to determine the extent of delays experienced in planning and constructing transmission lines in the continental United States. The reasons for the delays are identified for each line studied and their effect on the total electrical system is sought. Data was collected for 136 different lines either recently built or currently under study. Statistics were developed for each line in several categories and comparisons of lines delayed were made by company, area served and generation capacity. From the study presented here it was found that: right-of-way acquisition procedures including condemnation and easement negotiation practices delay more projects than local, state and federal regulatory requirements combined; load growth reductions particularly in the east have reduced the impact of regulatory delays; the south, southeast and southwestern areas of the country experience fewer delays in constructing transmission lines than the more populated states, and the cost for corridor delays was responded to for only 17 of the 142 projects surveyed. By far the most costly delay is the expense of condemning land for transmission right-of-way.

  1. Survey of transmission line corridors. [Data on delays in transmission line construction

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-05

    The intent of this study is to determine the extent of delays experienced in planning and constructing transmission lines in the continental United States. The reasons for the delays are identified for each line studied and their effect on the total electrical system is sought. Data was collected for 136 different lines either recently built or currently under study. Statistics were developed for each line in several categories and comparisons of lines delayed were made by company, area served and generation capacity. From the study presented here it was found that: right-of-way acquisition procedures including condemnation and easement negotiation practices delay more projects than local, state and federal regulatory requirements combined; load growth reductions particularly in the east have reduced the impact of regulatory delays; the south, southeast and southwestern areas of the country experience fewer delays in constructing transmission lines than the more populated states, and the cost for corridor delays was responded to for only 17 of the 142 projects surveyed. By far the most costly delay is the expense of condemning land for transmission right-of-way.

  2. Transmission-line networks cloaking objects from electromagnetic fields

    CERN Document Server

    Alitalo, Pekka; Jylhä, Liisi; Venermo, Jukka; Tretyakov, Sergei

    2007-01-01

    We consider a novel method of cloaking objects from the surrounding electromagnetic fields in the microwave region. The method is based on transmission-line networks that simulate the wave propagation in the medium surrounding the cloaked object. The electromagnetic fields from the surrounding medium are coupled into the transmission-line network that guides the waves through the cloak thus leaving the cloaked object undetected. The cloaked object can be an array or interconnected mesh of small inclusions that fit inside the transmission-line network.

  3. BERTHA: A versatile transmission line and circuit code

    Science.gov (United States)

    Hinshelwood, D. D.

    1983-11-01

    An improved version of the NRL transmission line code of W. H. Lupton is presented. The capabilities of the original program were extended to allow magnetically insulated transmission lines, plasma opening switches, imploding plasma loads and discrete element electrical networks, for example, to be modeled. BERTHA is used to simulate any system that is represented by a configuration of transmission line elements. The electrical behavior of the system is calculated by repeatedly summing the reflected and transmitted waves at the ends of each element. This program is versatile, easy to use and easily implemented on desktop microcomputers.

  4. ANALYSIS OF MULTICONDUCTOR TRANSMISSION LINES USING THE MACCORMACK METHOD

    Institute of Scientific and Technical Information of China (English)

    Dou Lei; Wang Zhiquan

    2006-01-01

    The MacCormack method is applied to the analysis of multiconductor transmission lines by introducing a new technique that does not require decoupling. This method can be used to analyze a wide range of problems and does not have to consider the matrix forms of distributed parameters. We have developed software named MacCormack Transmission Line Analyzer based on the proposed method. Numerical examples are presented to demonstrate the accuracy and efficiency of the method and illustrate its application to analyzing multiconductor transmission lines.

  5. High speed electrical transmission line design and characterization

    Science.gov (United States)

    Bates, R.; Buttar, C.; Buytaert, J.; Eklund, L.; de Acedo, L. F. S.; Longstaff, I.; Naik, S.; Sullivan, S.; Wraight, K.

    2017-02-01

    High Energy Physics (HEP) experiments have unique requirements for data communication. High data speeds, combined with extreme restrictions on materials allowed, leads to custom transmission lines. This paper will present transmission line design theory, simulation and testing methods. Transmission line designs options like flexes and rigid PCBs as well as cables will be studied. Finite Element Analysis (FEA) software packages simulate energy dissipation and quality of transmitted signals. The characterisation techniques of time-domain reflectometry and frequency-domain measurements are discussed and compared. Bit-error-rate testing is presented and its limitations for design discussed. Methods to improve quality, like three different types of equalization are described.

  6. Propagation of microwaves in gradient transmission lines: exactly solvable model

    Science.gov (United States)

    Shvartsburg, A. B.; Silin, N. V.

    2015-08-01

    Propagation of microwaves along the transmission line with smoothly continuously distributed capacitance and inductance (gradient transmission line) is considered in the framework of an exactly solvable model. The appearance of strong heterogeneity-induced plasma-like dispersion in gradient transmission line determined by the sizes and shapes of these distributions, is visualized by means of this model. Owing to this dispersion the energy transport in the line discussed can be ensured by both travelling and evanescent microwave modes, characterized by the real and imaginary wave numbers, respectively. The reflectance spectra for microwaves, incident on this heterogeneous transition section located between two homogeneous sections of transmission line are presented, the antireflection properties of this section are demonstrated. The interference of evanescent and anti-evanescent microwave modes is shown to provide the effective weakly attenuated energy transfer in the tunneling regime. The analogy between this microwave system and gradient nano-optical photonic barrier in revealed.

  7. Multimode circuit quantum electrodynamics with hybrid metamaterial transmission lines.

    Science.gov (United States)

    Egger, D J; Wilhelm, F K

    2013-10-18

    Quantum transmission lines are central to superconducting and hybrid quantum computing. In this work we show how coupling them to a left-handed transmission line allows circuit QED to reach a new regime: multimode ultrastrong coupling. Out of the many potential applications of this novel device, we discuss the preparation of multipartite entangled states and the simulation of the spin-boson model where a quantum phase transition is reached up to finite size effects.

  8. Impedance matching with an adjustable segmented transmission line.

    Science.gov (United States)

    Qian, Chunqi; Brey, William W

    2009-07-01

    A capability for impedance matching between the RF probe and the spectrometer is a standard requirement for NMR. Both lumped element and branched transmission line methods are widely used for this purpose. Here, we propose to use the segmented transmission line structure which is well known in wireless communications. It relies upon reflections between transmission lines of different characteristic impedances that are serially connected to match the impedance of a coil or resonator to the characteristic impedance of the NMR spectrometer. In our implementation, two quarter wave length dielectric slugs are placed within a coaxial transmission line. Adjustment of the positions of the slugs allows the variable tuning and matching needed for NMR probes, eliminating the need for variable capacitors and inductors. As a demonstration of the usefulness of this approach, we have incorporated a variable segmented transmission line into a home-built Variable Angle Spinning probe. Finally, we discuss the range of possible application for segmented transmission line networks in NMR probe design.

  9. Five Mass Power Transmission Line of a Ship Computer Modelling

    Directory of Open Access Journals (Sweden)

    Kazakoff Alexander Borisoff

    2016-03-01

    Full Text Available The work, presented in this paper, appears to be a natural continuation of the work presented and reported before, on the design of power transmission line of a ship, but with different multi-mass model. Some data from the previous investigations are used as a reference data, mainly from the analytical investigations, for the developed in the previ- ous study, frequency and modal analysis of a five mass model of a power transmission line of a ship. In the paper, a profound dynamic analysis of a concrete five mass dynamic model of the power transmission line of a ship is performed using Finite Element Analysis (FEA, based on the previously recommended model, investigated in the previous research and reported before. Thus, the partially validated by frequency analysis five mass model of a power transmission line of a ship is subjected to dynamic analysis. The objective of the work presented in this paper is dynamic modelling of a five mass transmission line of a ship, partial validation of the model and von Mises stress analysis calculation with the help of Finite Element Analysis (FEA and comparison of the derived results with the analytically calculated values. The partially validated five mass power transmission line of a ship can be used for definition of many dy- namic parameters, particularly amplitude of displacement, velocity and acceleration, respectively in time and frequency domain. The frequency behaviour of the model parameters is investigated in frequency domain and it corresponds to the predicted one.

  10. High aspect ratio transmission line circuits micromachined in silicon

    Science.gov (United States)

    Todd, Shane Truman

    The performance of complimentary metal-oxide-semiconductor (CMOS) monolithic microwave integrated circuits (MMICs) fabricated on silicon has improved dramatically. The scaling down of silicon transistors has increased the maximum frequency of transistors to the point where silicon MMICs have become a viable alternative to compound semiconductor MMICs in certain applications. A fundamental problem still exists in silicon MMICs however in that transmission lines fabricated on silicon can suffer from high loss due to the finite conductivity of the silicon substrate. A novel approach for creating low-loss transmission lines on silicon is presented in this work. Low-loss transmission lines are created on low resistivity silicon by using a micromachining method that combines silicon deep reactive ion etching (DRIE), thermal oxidation, electroplating, and planarization. Two types of high aspect ratio transmission lines are created with this method including high aspect ratio coplanar waveguide (hicoplanar) and semi-rectangular coaxial (semicoaxial). Transmission lines with impedances ranging from 20--80 O have been fabricated with minimum measured loss lower than 1 dB/cm at 67 GHz. Low-loss dielectrics are created for the high aspect ratio transmission lines using the mesa merging method. The mesa merging method works by creating silicon mesa arrays using DRIE and then converting and merging the mesa arrays into a solid oxide dielectric using thermal oxidation. The transmission lines are designed so that the fields penetrate the low-loss oxide dielectric and are isolated from the lossy silicon substrate. The mesa merging method has successfully created large volume oxide with depth up to 65 microm and width up to 240 microm in short oxidation times. Other advantages of the high aspect ratio transmission lines are demonstrated including low-loss over a wide impedance range, high isolation, and high coupling for coupled-line circuits. Transmission line models have been

  11. Atlas transmission line/transition design and fabrication status

    CERN Document Server

    Ballard, E O; Davis, H A; Elizondo, J M; Gribble, R F; Nielsen, K E; Parker, G V; Ricketts, R L; Valdez, G A

    1999-01-01

    Atlas is a pulsed-power facility under development at Los Alamos National Laboratory to drive high-energy density experiments. Design has been completed for this new generation pulsed-power machine consisting of an azimuthal array of 24, 240-kV Marx modules and transmission lines supplying current to the load region at the machine center. The transmission line consists of a cable header, load protection switch, and tri-plate assembly interfacing to the center transition section. The cable header interface to the Marx module provides a mechanism to remove the Marx module for maintenance without removing other components of the transmission line. The load protection switch provides a mechanism for protecting the load during charging of the Marx in the event of a pre-fire condition. The aluminum tri-plate is a low-inductance transmission line that carries radial current flow from the Marx energy storage system at the machine periphery toward the load. All transmission line components are oil insulated except the...

  12. Application of EPON Technology in Transmission Line Video Monitoring

    Directory of Open Access Journals (Sweden)

    Xia Zongze

    2015-01-01

    Full Text Available The operating condition of transmission lines directly determines the efficiency of the power system. Therefore, faced with a complex operating environment, it is extremely important to protect transmission line video monitoring. At present, the technology widely used in the power distribution and network communication in domestic power industry is EPON technology. This technology has a broad application prospect on the transmission of electrical circuit video monitoring information. On this basis, this paper carries out a further research on the application of EPON technology in transmission line video monitoring. This paper firstly proposes the design principle of transmission line video monitoring, and on this basis, it carries out a comparative analysis of merits and demerits of different types of EPON networking schemes. In addition, quantification is given for the EPON networking power consumption, so as to obtain a complete EPON combining scheme which is combined with specific examples to validate, and finally realize that the EPON technology has a certain application value because it is in line with various indicators after application in transmission line video monitoring.

  13. Transmission line matrix modelling of thermal injuries to skin.

    Science.gov (United States)

    Aliouat Bellia, S; Saidane, A; Hamou, A; Benzohra, M; Saiter, J M

    2008-08-01

    A numerical model based on the transmission line matrix method is presented for the quantitative prediction of skin burn resulting from exposure of a specific region of human skin surface to a high temperature heat source. Transient temperatures were numerically estimated by Pennes' bioheat equation, and the damage function denoting the extent of burn was calculated using the Arrhenius assumptions for protein damage rate. A two-dimensional transmission line matrix model was used to predict the effects of exposure time and structure thicknesses on the transient temperature distribution and damage extent. Compared with other numerical sources the transmission line matrix results revealed good agreement, suggesting that this method may be an effective tool for the thermal diagnostic of burns.

  14. Transmission line icing prediction based on DWT feature extraction

    Science.gov (United States)

    Ma, T. N.; Niu, D. X.; Huang, Y. L.

    2016-08-01

    Transmission line icing prediction is the premise of ensuring the safe operation of the network as well as the very important basis for the prevention of freezing disasters. In order to improve the prediction accuracy of icing, a transmission line icing prediction model based on discrete wavelet transform (DWT) feature extraction was built. In this method, a group of high and low frequency signals were obtained by DWT decomposition, and were fitted and predicted by using partial least squares regression model (PLS) and wavelet least square support vector model (w-LSSVM). Finally, the final result of the icing prediction was obtained by adding the predicted values of the high and low frequency signals. The results showed that the method is effective and feasible in the prediction of transmission line icing.

  15. Computation of nonuniform transmission lines using the FDTD method

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, G.C.; Paulino, J.O.S. [Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil). School of Engineering

    1997-12-31

    Calculation of lightning overvoltages on transmission lines has been described. Lightning induced overvoltages are of great significance under certain conditions because of the main characteristics of the phenomena. The lightning channel model is one of the most important parameters essential to obtaining the generated electromagnetic fields. In this study, nonuniform transmission line equations were solved using the finite difference method and the leap-frog scheme, the Finite Difference Time Domain (FDTD) method. The subroutine was interfaced with the Electromagnetic Transients Program (EMTP). Two models were used to represent the characteristic impedance of the nonuniform lines used to model the transmission line towers and the lightning main channel. The advantages of the FDTD method was the much smaller code and faster processing time. 35 refs., 5 figs.

  16. Computation of electrical environmental effects of transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Kanya Kumari, M.; Rajesh Kumar, O.; Nambudiri, P.V.V.; Srinivasan, K.N. [Central Power Research Institute, Bangalore (India)

    1999-07-01

    EHV and UHV AC Transmission lines and electrical equipment produce electric and magnetic fields around their vicinity which are likely to produce various induction and biological effects when their levels exceed certain values. In addition to this, the electric field may initiate corona resulting in corona loss with associated interference nuisances like radio interference, audible noise etc. Transmission line planners should take these factors into consideration at the design stage. This necessitates the requirement for establishing computational methods to estimate the above mentioned factors. The paper presents the software developed in CPRI for this purpose and discusses the algorithm used in the software for these computations. (author)

  17. ANALYSIS OF CIRCUITS WITH MULTIPLE COUPLED LOSSY TRANSMISSION LINES

    DEFF Research Database (Denmark)

    Dalby, Arne Brejning

    1997-01-01

    The analysis of coupled lossy transmission line structures like microwave directional couplers and filters, 3-phase power cable networks or a databus is not simple. In this paper it is shown that the admittance parameters for the 2N port network, N coupled lossy transmission lines form, may be fo...... be found using a set of almost arbitrary (orthogonal) quasi propagation modes instead of the true modes, if the up-per frequency is so low that the electrical length of the lines is smaller than about 1/3 of the wavelength for the propagation mode with the lowest phase velocity....

  18. Electrical and Biological Effects of Transmission Lines: A Review.

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jack M.

    1989-06-01

    This review describes the electrical properties of a-c and d-c transmission lines and the resulting effects on plants, animals, and people. Methods used by BPA to mitigate undesirable effects are also discussed. Although much of the information in this review pertains to high-voltage transmission lines, information on distribution lines and electrical appliances is included. The electrical properties discussed are electric and magnetic fields and corona: first for alternating-current (a-c) lines, then for direct current (d-c).

  19. Reconfigurable Wave Velocity Transmission Lines for Phased Arrays

    Science.gov (United States)

    Host, Nick; Chen, Chi-Chih; Volakis, John L.; Miranda, Felix

    2013-01-01

    Phased array antennas showcase many advantages over mechanically steered systems. However, they are also more complex, heavy and most importantly costly. This presentation paper presents a concept which overcomes these detrimental attributes by eliminating all of the phase array backend (including phase shifters). Instead, a wave velocity reconfigurable transmission line is used in a series fed array arrangement to allow phase shifting with one small (100mil) mechanical motion. Different configurations of the reconfigurable wave velocity transmission line are discussed and simulated and experimental results are presented.

  20. A development of ITV system for power transmission line monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Hong Keun; Kim, Seok Ku; Lee, Kwang Joong; Lee, Won Bin [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

    1995-12-31

    Transmission lines which are important to supply the electricity installed on the terrestrially severe site such as mountains needed to be monitored to prevent electric fault by snow accelerating, icing, tree contact, fire etc. Inspections by human patrol has been done but it seems not so efficient and satisfiable. To cope with this a transmission line monitoring system using industrial television and OPGW was developed and field trilled at the site. This paper describes about the optical video transceiver, video distributor and control devices (author).

  1. Algorithm for predictive control implementation on fiber optic transmission lines

    Science.gov (United States)

    Andreev, Vladimir A.; Burdin, Vladimir A.; Voronkov, Andrey A.

    2014-04-01

    This paper presents the algorithm for predictive control implementation on fiber-optic transmission lines. In order to improve the maintenance of fiber optic communication lines, the algorithm prediction uptime optic communication cables have been worked out. It considers the results of scheduled preventive maintenance and database of various works on the track cable line during maintenance.

  2. Stabilizing control for power converters connected to transmission lines

    NARCIS (Netherlands)

    Zainea, Marius; Schaft, Arjan van der; Buisson, Jean

    2007-01-01

    This paper proposes a switching control strategy for the set-point stabilization of a power converter connected via a transmission line to a resistive load. The strategy employs a Lyapunov function that is directly based on energy considerations of the power converter, as well as of the transmission

  3. Rigorous theoretical derivation of lumped models to transmission line systems

    Institute of Scientific and Technical Information of China (English)

    Zhao Jixiang

    2012-01-01

    By virtue of the negative electric parameter concept,i.e.negative lumped resistance,inductance,conductance and capacitance (N-RLGC),the lumped equivalent models of transmission line systems,including the circuit model,two-port π-network and T-network,are given.We start from the N-segment-ladder-like equivalent networks composed distributed parameters,and achieve the input impedance in the form of a continued fraction.Utilizing the continued fraction theory,the expressions of input impedance are obtained under three kinds of extreme cases,i.e.the load impedances are equal to zero,infinity and characteristic impedance,respectively.When the number of segment N is limited to infinity,they are transformed to lumped elements.Comparison between the distributed model and lumped model of transmission lines,the expression of tanh yd,which is the key term in the transmission line equations,are obtained by RLGC,furthermore,according to input admittance,admittance matrix and ABCD matrix of transmission lines,the lumped equivalent circuit models,π-networks and T-networks have been given.The models are verified in the frequency and time domain,respectively,showing that the models are accurate and efficient.

  4. Overhead three-phase transmission lines - Non-diagonalizable situations

    Energy Technology Data Exchange (ETDEWEB)

    Faria, J.A.B. (Centro de Electrotecnia da U.T.L. - Instituto Superior Tecnico, 1096 Lisboa (PT))

    1988-10-01

    Physically realizable transmission lines exist to which the standard modal theory does not apply since the ZY diagonalization cannot always be undertaken successfully. In this paper the non-diagonalizing conditions for typical overhead three-phase lines are established. Algorithms are described and implemented to synthesize concrete non-diagonalizable configurations, numerical examples being presented and discussed.

  5. Asymmetrical coupled coplanar-type transmission lines with anisotropic substrates

    Science.gov (United States)

    Kitazawa, T.; Hayashi, Y.; Mittra, R.

    1986-07-01

    Various types of transmission lines with anisotropic substances were investigated for use in microwave and millimeter wave integrated circuits. These include single and coupled striplines, slot lines, and coplanar-type transmission lines. The coplanar-type transmission lines (CTLs) are promising because of their easy adaptation to shunt element connections. The application of coupled coplanar-type transmission lines (C-CTLs) were studied based on the quasistatic and hybrid mode formulations and accurate numerical values are available for the cases with isotropic and/or anisotropic substrates. However, most of them assume structural symmetry. The theoretical approach for the asymmetrical version is available only for the propagation constant of the case with a single isotropic substrate. The analytical method for the general structure of asymmetrical C-CTLs with an anisotropic substrate. This method includes both the hybrid mode and the quasistatic formulations and is useful for accurately computing the characteristics impedances as well as propagation constants of various types of assymetrical C-CTLs.

  6. THE EC H&CD TRANSMISSION LINE FOR ITER

    NARCIS (Netherlands)

    Gandini, F.; Bigelow, T. S.; Becket, B.; Caughman, J. B.; Cox, D.; Darbos, C.; Gassmann, T.; Henderson, M. A.; Jean, O.; Kajiwara, K.; Kobayashi, N.; Nazare, C.; Oda, Y.; Omori, T.; Purohit, D.; Rasmussen, D. A.; Ronden, D. M. S.; Saibene, G.; Sakamoto, K.; Shapiro, M. A.; Takahashi, K.; Temkin, R. J.

    2011-01-01

    The transmission line (TL) subsystem associated with the ITER electron cyclotron heating and current drive system has reached the conceptual design maturity. At this stage the responsibility of finalizing the design has been transferred from the ITER Organization to the U.S. Domestic Agency. The pur

  7. 78 FR 60273 - Granby Pumping Plant Switchyard-Windy Gap Substation Transmission Line Rebuild, Grand County...

    Science.gov (United States)

    2013-10-01

    ... Area Power Administration Granby Pumping Plant Switchyard-Windy Gap Substation Transmission Line... Substation (Project) transmission line in Grand County, Colorado. The transmission line is 13.6 miles long... Western's existing transmission line between the Windy Gap Substation and Stillwater Tap and provide a...

  8. Beam coupling impedances of fast transmission-line kickers.

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S. (Sergey)

    2002-01-01

    Fast transmission-line kickers contain no ferrite and consist of two long metallic parallel plates supported by insulators inside a beam pipe. A beam is deflected by both the electric and magnetic fields of a TEM wave created by a pulse propagating along the strips in the direction opposite to the beam. Computations of the beam coupling impedances for such structures are difficult because of their length. In the paper, the beam coupling impedances of transmission-line kickers are calculated by combining analytical and numerical methods: the wake potentials computed in short models are extended analytically to obtain the wakes for the long kickers, and then the corresponding beam impedances are derived. At very low frequencies the results are compared with simple analytical expressions for the coupling impedances of striplines in beam position monitors.

  9. TRANSIENT ANALYSIS OF NONUNIFORM TRANSMISSION LINES WITH NONLINEAR TERMINAL NETWORKS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A semi-analytical method in time domain is presented for analysis of the transient response of nonuniform transmission lines. In this method, the telegraph equations in time domain is differenced in space domain first, and is transformed into a set of first-order differential equations of voltage and current with respect to time. By integrating these differential equations with respect to time, and precise computation, the solution of these differential equations can be obtained. This method can solve the transient response of various kinds of transmission lines with arbitrary terminal networks. Particularly, it can analyze the nonuniform lines with initial conditions, for which there is no existing effective method to analyze the time response so far. The results obtained with this method are stable and accurate. Two examples are given to illustrate the application of this method.

  10. A novel transmission line protection using DOST and SVM

    Directory of Open Access Journals (Sweden)

    M. Jaya Bharata Reddy

    2016-06-01

    Full Text Available This paper proposes a smart fault detection, classification and location (SFDCL methodology for transmission systems with multi-generators using discrete orthogonal Stockwell transform (DOST. The methodology is based on synchronized current measurements from remote telemetry units (RTUs installed at both ends of the transmission line. The energy coefficients extracted from the transient current signals due to occurrence of different types of faults using DOST are being utilized for real-time fault detection and classification. Support vector machine (SVM has been deployed for locating the fault distance using the extracted coefficients. A comparative study is performed for establishing the superiority of SVM over other popular computational intelligence methods, such as adaptive neuro-fuzzy inference system (ANFIS and artificial neural network (ANN, for more precise and reliable estimation of fault distance. The results corroborate the effectiveness of the suggested SFDCL algorithm for real-time transmission line fault detection, classification and localization.

  11. Tunable Lowpass Filter with RF MEMS Capacitance and Transmission Line

    Directory of Open Access Journals (Sweden)

    Shimul C. Saha

    2012-01-01

    Full Text Available We have presented an RF MEMS tuneable lowpass filter. Both distributed transmission lines and RF MEMS capacitances were used to replace the lumped elements. The use of RF MEMS capacitances gives the flexibility of tuning the cutoff frequency of the lowpass filter. We have designed a low-pass filter at 9–12 GHz cutoff frequency using the theory of stepped impedance transmission lines. A prototype of the filter has been fabricated using parallel plate capacitances. The variable shunt capacitances are formed by a combination of a number of parallel plate RF MEMS capacitances. The cutoff frequency is tuned from C to X band by actuating different combinations of parallel capacitive bridges. The measurement results agree well with the simulation result.

  12. Analytical Model for High Impedance Fault Analysis in Transmission Lines

    Directory of Open Access Journals (Sweden)

    S. Maximov

    2014-01-01

    Full Text Available A high impedance fault (HIF normally occurs when an overhead power line physically breaks and falls to the ground. Such faults are difficult to detect because they often draw small currents which cannot be detected by conventional overcurrent protection. Furthermore, an electric arc accompanies HIFs, resulting in fire hazard, damage to electrical devices, and risk with human life. This paper presents an analytical model to analyze the interaction between the electric arc associated to HIFs and a transmission line. A joint analytical solution to the wave equation for a transmission line and a nonlinear equation for the arc model is presented. The analytical model is validated by means of comparisons between measured and calculated results. Several cases of study are presented which support the foundation and accuracy of the proposed model.

  13. Installation of optical shieldwire on existing transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Trausch, S. (Fluor Daniel, Chicago, IL (US))

    1988-01-01

    The author reports the development of a communication network between Minneapolis and Chicago. The fiber optics cable was installed, with a few exceptions, on existing transmission lines. Most of the utilized transmission structures are 138-161 kV wood pole H-frame structures with two shield wires. One of the shield wires was removed and replaced by the fiber optic cable. In a 30-mile section the fiber optic cable was installed on 345 kV lines supported on steel poles and steel lattice towers. Generally, however, 345 kV lines were avoided because it was difficult to obtain outages for the installation of the optic ground wire (OPGW). In some cases, where existing transmission line structures could not be used, the fiber optic cable was installed on 30- to 50-foot single wood pole structures designed to support this cable.

  14. Microtubule as a Transmission Line for Ionic Currents

    Institute of Scientific and Technical Information of China (English)

    ILI(C) D.I.; SATARI(C) M.V.; RALEVI(C) N.

    2009-01-01

    We establish a new model for ionic waves along microtubules based on polyelectrolyte features of cylindrical biopolymers. The nonlinear transmission line described by a nonlinear differential equation is obtained with stable kink solution pertinent to the shape of the front of accompanying potential. The localized ionic wave could be used to explain the behavior of microtubules as biomolecular transistors capable of amplifying electrical information in neurons.

  15. Power transmission line operating modes calculation with controllable phase shifters

    Science.gov (United States)

    Astashev, M. G.; Novikov, M. A.; Panfilov, D. I.; Rashitov, P. A.; Remizevich, T. V.; Fedorova, M. I.

    2016-12-01

    The article contains the analysis of the influence of the phase shifter (PS) on the energy processes in the power transmission line in terms of the two-unit model of the electric network. The approach to synthesis of the models regulated by the phase shifter providing for both calculation of the steady operation modes of the electric networks with the phase shifters and research of the electromagnetic processes and designing of the device itself is offered.

  16. Integrated micromachined transmission lines and endfire slotline antennas

    Science.gov (United States)

    Gearhart, Steven S.; Willke, Theodore L.; Onggosanusi, Eko N.

    1997-09-01

    An entirely new class of micromachined 3D microwave and millimeter-wave integrated circuits and antennas are being developed at the University of Wisconsin-Madison using a subset o the LIGA micromachining process. The deep x-ray lithography and metal plating portions of the LIGA process are used to precisely form tall metal structures on semiconductor and dielectric substrates. This micromachining process allows metal height to be included as a parameter in the design of integrated circuits, which will permit several important advancements in high frequency waveguiding circuits and integrated antennas. With appropriate thick- metal cross-sectional geometry, transmission line losses and dispersion may both be reduced on a given substrate. Vertical-walled metal structures allow increased control over element-to-element coupling for integrated coupled-line filters and couplers and result in very significant reductions in ohmic loss. It will be demonstrated that the first single-level coupled-line 3dB coupler can be fabricated using the LIGA process. In addition, the mechanical properties of the thick metal structures will be utilized in the fabrication of integrated antennas and transmission lines that are unsupported by a dielectric substrate. The elimination of the substrate beneath antennas reduces losses to substrate modes, and the elimination o the substrate beneath transmission line filters is necessary for extremely high Q integrated filters. This paper will present simulated loss results that demonstrate the advantages of thick metal transmission lines, measured results of a coupled-line bandpass filter, and a recently fabricated thick-metal tapered slotline antenna which extends nearly a centimeter off of the edge of a GaAs wafer.

  17. Sensor Placement For Structural Monitoring of Transmission Line Towers

    Directory of Open Access Journals (Sweden)

    Benny eRaphael

    2015-11-01

    Full Text Available Transmission line towers are usually analyzed using linear elastic idealized truss models. Due to the assumptions used in the analysis, there are discrepancies between the actual results obtained from full scale prototype testing and the analytical results. Therefore, design engineers are interested in assessing the actual stress levels in transmission line towers. Since it is costly to place sensors on every member of a tower structure, the best locations for sensors need to be carefully selected. This study evaluates a methodology for sensor placement in transmission line towers. The objective is to find optimal locations for sensors such that the real behavior of the structure can be explained from measurements. The methodology is based on the concepts of entropy and model falsification. Sensor locations are selected based on maximum entropy such that there is maximum separation between model instances that represent different possible combinations of parameter values which have uncertainties. The performance of the proposed algorithm is compared to that of an intuitive method in which sensor locations are selected where the forces are maximum. A typical 220 kV transmission tower is taken as case study in this paper. It is shown that the intuitive method results in much higher number of non-separable models compared to the optimal sensor placement algorithm. Thus the intuitive method results in poor identification of the system.

  18. Nanofabrication of planar split ring resonators for negative refractive index metamaterials in the infrared range

    Directory of Open Access Journals (Sweden)

    ZORAN JAKSIC

    2006-06-01

    Full Text Available Experimental nanofabrication of planar structures for one-dimensional metamaterials designed to achieve a negative effective refractive index in the mid-infrared range (5–10 micrometers was performed. Double split ring and complementary double split ring resonators (SRR and CSRR with square and circular geometries, were chosen to be fabricated since these are the basic building blocks to achieve a negative effective dielectric permittivity and magnetic permeability. Scanning probe nanolithography with z-scanner movement was used to fabricate straight-line and curvilinear segments with a line width of 80 – 120 nm. The geometries were delineated in 20 nm thin silver layers sputter-deposited on a positive photoresist substrate spin-coated on polished single crystal silicon wafers, as well as on polycarbonate slabs. The morphology of the structures was characterized by atomic force microscopy. The feature repeatibility was 60 – 150 nm, depending on the process conditions and the feature complexity. The nanolithographic groove depth in different samples ranged from 4 nm to 80 nm.

  19. Analysis of surface plasmon waves in metaldielectric- metal structures and the criterion for negative refractive index.

    Science.gov (United States)

    Yang, Tian; Crozier, Kenneth B

    2009-01-19

    Surface plasmon waves in metal-dielectric-metal structures have been theoretically examined. Because of the existence of evanescent waves that can have comparable or smaller decay rates than the propagating waves, the sign of dispersion does not necessarily indicate the sign of effective refractive index for these structures. By using the direction of energy decay to distinguish the sign of index, we have obtained different results and insights from previous reports. We also propose an approach to increase the bandwidth and decrease the loss of negative index surface Plasmon propagation in the MDM structure, by simply changing the properties of its dielectric layer.

  20. Negative refractive index and acoustic superlens from multiple scattering in single negative metamaterials.

    Science.gov (United States)

    Kaina, Nadège; Lemoult, Fabrice; Fink, Mathias; Lerosey, Geoffroy

    2015-09-03

    Metamaterials, man-made composite media structured on a scale much smaller than a wavelength, offer surprising possibilities for engineering the propagation of waves. One of the most interesting of these is the ability to achieve superlensing--that is, to focus or image beyond the diffraction limit. This originates from the left-handed behavior--the property of refracting waves negatively--that is typical of negative index metamaterials. Yet reaching this goal requires the design of 'double negative' metamaterials, which act simultaneously on the permittivity and permeability in electromagnetics, or on the density and compressibility in acoustics; this generally implies the use of two different kinds of building blocks or specific particles presenting multiple overlapping resonances. Such a requirement limits the applicability of double negative metamaterials, and has, for example, hampered any demonstration of subwavelength focusing using left-handed acoustic metamaterials. Here we show that these strict conditions can be largely relaxed by relying on media that consist of only one type of single resonant unit cell. Specifically, we show with a simple yet general semi-analytical model that judiciously breaking the symmetry of a single negative metamaterial is sufficient to turn it into a double negative one. We then demonstrate that this occurs solely because of multiple scattering of waves off the metamaterial resonant elements, a phenomenon often disregarded in these media owing to their subwavelength patterning. We apply our approach to acoustics and verify through numerical simulations that it allows the realization of negative index acoustic metamaterials based on Helmholtz resonators only. Finally, we demonstrate the operation of a negative index acoustic superlens, achieving subwavelength focusing and imaging with spot width and resolution 7 and 3.5 times better than the diffraction limit, respectively. Our findings have profound implications for the physics of metamaterials, highlighting the role of their subwavelength crystalline structure, and hence entering the realm of metamaterial crystals. This widens the scope of possibilities for designing composite media with novel properties in a much simpler way than has been possible so far.

  1. Slow light in a dielectric waveguide with negative-refractive-index photonic crystal cladding.

    Science.gov (United States)

    He, Jinlong; Jin, Yi; Hong, Zhi; He, Sailing

    2008-07-21

    A slow light waveguide made of a dielectric slab inserted in a two-dimensional photonic crystal with a negative effective refractive index is proposed and numerically studied. The waveguide may possess modes with zero group velocity, and its frequency varies with the thickness of the waveguide. A linearly tapered left-handed photonic crystal waveguide is also proposed and studied. It is shown that the so-called 'trapped rainbow' proposed by Tsakmakidis, Boardman, and Hess [1] is difficult to realize due to a coupling of forward- and backward-propagating modes near zero group velocity. However, different frequency components of a broadband excitation can still be separated through partial accumulation at waveguide sections of different thicknesses.

  2. Metal slab superlens-negative refractive index versus inclined illumination: discussion.

    Science.gov (United States)

    Grave de Peralta, Luis

    2015-09-01

    I describe experiments using a combination of an optical microscope and a plasmonic ultrathin condenser (UTC). The UTC's structure is similar to the original proposal of a silver slab superlens. I show that the observed improvement in image resolution is determined by the well-known equation describing the resolution obtainable when a condenser is included in the microscope setup. I argue that the described experiments indicate that the so-called metal slab superlens is better described as a novel ultrathin microscope condenser, and the observed improvement in resolution is due to the illumination of the object under observation with inclined light produced by the plasmonic UTC. Implications of this opinion for the development of an optical nanoscope based on plasmonic UTCs are presented.

  3. Tunable dual-band negative refractive index in ferrite-based metamaterials.

    Science.gov (United States)

    Bi, Ke; Zhou, Ji; Zhao, Hongjie; Liu, Xiaoming; Lan, Chuwen

    2013-05-06

    A tunable dual-band ferrite-based metamaterial has been investigated by experiments and simulations. The negative permeability is realized around the ferromagnetic resonance (FMR) frequency which can be influenced by the dimension of the ferrites. Due to having two negative permeability frequency regions around the two FMR frequencies, the metamaterials consisting of metallic wires and ferrite rods with different sizes possess two passbands in the transmission spectra. The microwave transmission properties of the ferrite-based metamaterials can be not only tuned by the applied magnetic field, but also adjusted by the dimension of the ferrite rods. A good agreement between experimental and simulated results is demonstrated, which confirms that the tunable dual-band ferrite-based metamaterials can be used for cloaks, antennas and absorbers.

  4. Invertebrate superposition eyes-structures that behave like metamaterial with negative refractive index

    NARCIS (Netherlands)

    Stavenga, D. G.

    2006-01-01

    The superposition eyes of moths and lobsters are described with the geometrical optics for a refractive surface between two media, where the refractive index of the image space is negative. Consequently, the eye power and the object focal length are negative, whereas the image focal length is positi

  5. Transmission of evanescent wave modes through a slab of negative-refractive-index material.

    Science.gov (United States)

    de Wolf, David A

    2011-02-01

    There has been a long-standing argument about Pendry's suggestion that a plane harmonic evanescent (surface) wave along the interface between free space and a slab of ɛ=-1, μ=-1 double-negative (DNG) medium will emerge on the far side with recovery of phase and amplitude. While this is possible, it is subject to parameter restrictions. This work generalizes previous work and now gives analytical criteria for when to expect such a recovery in a Smith-Kroll DNG medium. Basically this requires, among other things, a relatively narrow bandwidth and relatively small transverse-mode component. There also is a very strong dependence on the ratio of slabwidth to plasma wavelength.

  6. Composite chiral metamaterials with negative refractive index and high values of the figure of merit.

    Science.gov (United States)

    Li, Zhaofeng; Alici, Kamil Boratay; Caglayan, Humeyra; Kafesaki, Maria; Soukoulis, Costas M; Ozbay, Ekmel

    2012-03-12

    A composite chiral metamaterial (CCMM) is designed and studied both numerically and experimentally. The CCMM is constructed by the combination of a continuous metallic wires structure and a purely chiral metamaterial (CMM) that consists of conjugated Rosettes. For the CMM, only very small, useful bands of negative index can be obtained for circularly polarized waves. These bands are all above the chiral resonance frequencies because of the high value of the effective parameter of relative permittivity ε. After the addition of the continuous metallic wires, which provide negative permittivity, the high value of ε can be partially compensated. Thus, a negative index band for the left circularly polarized wave that is below the chiral resonance frequency is obtained for the CCMM. At the same time, a negative index band for the right circularly polarized wave that is above the chiral resonance frequency is also obtained. Furthermore, both negative index bands correspond to the transmission peaks and have high values of the figure of merit. Therefore, the CCMM design that is proposed here is more suitable than the CMM for the construction of chiral metamaterials with a negative index.

  7. Optical Pulse Dynamics in Active Metamaterials with Positive and Negative Refractive Index

    CERN Document Server

    Korotkevich, Alexander O; Kovacic, Gregor; Roytburd, Victor; Maimistov, Andrei I; Gabitov, Ildar R; .,

    2013-01-01

    We study numerically the propagation of two-color light pulses through a metamaterial doped with active atoms such that the carrier frequencies of the pulses are in resonance with two atomic transitions in the $\\Lambda$ configuration and that one color propagates in the regime of positive refraction and the other in the regime of negative refraction. In such a metamaterial, one resonant color of light propagates with positive and the other with negative group velocity. We investigate nonlinear interaction of these forward- and backward-propagating waves, and find self-trapped waves, counter-propagating radiation waves, and hot spots of medium excitation.

  8. A Soft 3D Acoustic Metafluid with Dual-Band Negative Refractive Index.

    Science.gov (United States)

    Raffy, Simon; Mascaro, Benoit; Brunet, Thomas; Mondain-Monval, Olivier; Leng, Jacques

    2016-03-02

    Spherical silica xerogels are efficient acoustic Mie resonators. When these sub-wavelength inclusions are dispersed in a matrix, the final metafluid may display a negative acoustic refractive index upon a set of precise constraints concerning material properties, concentration, size, and dispersity of the inclusions. Because xerogels may sustain both pressure and shear waves, several bands with negative index can be tailored.

  9. Comparison of negative refractive index materials with circular, elliptical and rectangular holes.

    Science.gov (United States)

    Ku, Zahyun; Brueck, S R J

    2007-04-16

    Negative-index metamaterials (NIMs) at near infrared wavelengths (~2 mum) are fabricated with circular, elliptical and rectangular holes penetrating through metal/dielectric/metal films. All three NIM structures exhibit similar figures of merit; however, the transmission is higher for the NIM with rectangular holes as a result of an improved impedance match with the substrate-superstrate (air-glass) combination.

  10. Invertebrate superposition eyes-structures that behave like metamaterial with negative refractive index

    NARCIS (Netherlands)

    Stavenga, D. G.

    2006-01-01

    The superposition eyes of moths and lobsters are described with the geometrical optics for a refractive surface between two media, where the refractive index of the image space is negative. Consequently, the eye power and the object focal length are negative, whereas the image focal length is

  11. Negative refractive index and higher-order harmonics in layered metallodielectric optical metamaterials

    CERN Document Server

    Maas, Ruben; Parsons, James; Polman, Albert

    2014-01-01

    We study the propagation of light in a three-dimensional double-periodic Ag/TiO2 multilayer metamaterial composed of coupled plasmonic waveguides operating in the visible and UV spectral range. For these frequencies, light propagation in the plane of the waveguides is described by a negative phase velocity, while for the orthogonal direction light propagation is described by a Bloch wave composed of a large number of harmonics. As a result, the material cannot generally be described by a single phase index: decomposing the Bloch wave into different harmonics we show that for the wavelength range of interest the positive index m=1 harmonic dominates the propagation of light in the orthogonal direction. These results are corroborated by numerical simulations and optical refraction experiments on a double-periodic Ag/TiO2 multilayer metamaterial prism in the 380-600 nm spectral range, which show that positive refraction associated with right-handed harmonics dominates. Studying the isofrequency contours we find ...

  12. Optical and acoustic metamaterials: superlens, negative refractive index and invisibility cloak

    Science.gov (United States)

    Wong, Zi Jing; Wang, Yuan; O'Brien, Kevin; Rho, Junsuk; Yin, Xiaobo; Zhang, Shuang; Fang, Nicholas; Yen, Ta-Jen; Zhang, Xiang

    2017-08-01

    Metamaterials are artificially engineered materials that exhibit novel properties beyond natural materials. By carefully designing the subwavelength unit cell structures, unique effective properties that do not exist in nature can be attained. Our metamaterial research aims to develop new subwavelength structures with unique physics and experimentally demonstrate unprecedented properties. Here we review our research efforts in optical and acoustic metamaterials in the past 15 years which may lead to exciting applications in communications, sensing and imaging.

  13. Theory and Circuit Model for Lossy Coaxial Transmission Line

    Energy Technology Data Exchange (ETDEWEB)

    Genoni, T. C.; Anderson, C. N.; Clark, R. E.; Gansz-Torres, J.; Rose, D. V.; Welch, Dale Robert

    2017-04-01

    The theory of signal propagation in lossy coaxial transmission lines is revisited and new approximate analytic formulas for the line impedance and attenuation are derived. The accuracy of these formulas from DC to 100 GHz is demonstrated by comparison to numerical solutions of the exact field equations. Based on this analysis, a new circuit model is described which accurately reproduces the line response over the entire frequency range. Circuit model calculations are in excellent agreement with the numerical and analytic results, and with finite-difference-time-domain simulations which resolve the skindepths of the conducting walls.

  14. Walking Posture Control of Transmission Line Single Arm Inspection Robot

    Science.gov (United States)

    Yan, Yu; Liu, Xiaqing; Li, Jinliang; Ou, Yuexiong

    2017-07-01

    To control the walking posture according to transmission line single arm inspection robot, the robot is divided into normal walking and climbing walking two state, and gives the definition, then based on the state space method of state variable feedback and PD control method is used to control the two states, two kinds of control method of simulation by using Matlab, in the end, the two control methods proposed is validated in the actual circuit structures. The results show that, the proposed control method is rapid and effective, and can meet the needs of practical application.

  15. Field quality measurements of a 2-Tesla transmission line magnet

    Energy Technology Data Exchange (ETDEWEB)

    Velev, G.V.; Foster, W.; Kashikhin, V.; Mazur, P.; Oleck, A.; Piekarz, H.; Schlabach, P.; Sylvester, C.; /Fermilab; Wake, M.; /KEK, Tsukuba

    2005-09-01

    A prototype 2-Tesla superconducting transmission line magnet for future hadron colliders was designed, built and tested at Fermilab. The 1.5 m long, combined-function gradient-dipole magnet has a vertical pole aperture of 20 mm. To measure the magnetic field quality in such a small magnet aperture, a specialized rotating coil of 15.2 mm diameter, 0.69 m long was fabricated. Using this probe, a program of magnetic field quality measurements was successfully performed. Results of the measurements are presented and discussed.

  16. MATHEMATICAL MODELS FOR SOME RADIO-FREQUENCY TRANSMISSION-LINE TRANSFORMERS

    Science.gov (United States)

    MATRICES(MATHEMATICS), *PHASE SHIFT CIRCUITS, *RADIOFREQUENCY, *TRANSFORMERS, *TRANSMISSION LINES, BROADBAND, DIELECTRIC PROPERTIES, ELECTRICAL IMPEDANCE, FERRITES, IMPEDANCE MATCHING , MATHEMATICAL ANALYSIS.

  17. 7 CFR 1726.76 - Substation and transmission line materials and equipment.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 11 2010-01-01 2010-01-01 false Substation and transmission line materials and... Substation and Transmission Facilities § 1726.76 Substation and transmission line materials and equipment. (a... $500,000 and for all materials. (b) Standards and specifications. Substation and transmission line...

  18. 49 CFR 192.713 - Transmission lines: Permanent field repair of imperfections and damages.

    Science.gov (United States)

    2010-10-01

    ... Maintenance § 192.713 Transmission lines: Permanent field repair of imperfections and damages. (a) Each imperfection or damage that impairs the serviceability of pipe in a steel transmission line operating at or... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Permanent field repair...

  19. 49 CFR 192.717 - Transmission lines: Permanent field repair of leaks.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Permanent field repair of... § 192.717 Transmission lines: Permanent field repair of leaks. Each permanent field repair of a leak on a transmission line must be made by— (a) Removing the leak by cutting out and replacing...

  20. 49 CFR 192.707 - Line markers for mains and transmission lines.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Line markers for mains and transmission lines. 192... § 192.707 Line markers for mains and transmission lines. (a) Buried pipelines. Except as provided in... buried main and transmission line: (1) At each crossing of a public road and railroad; and (2)...

  1. 50 CFR 29.21-8 - Electric power transmission line rights-of-way.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Electric power transmission line rights-of... General Regulations § 29.21-8 Electric power transmission line rights-of-way. By accepting a right-of-way for a power transmission line, the applicant thereby agrees and consents to comply with and be...

  2. 76 FR 15970 - Central Ferry to Lower Monumental 500-kilovolt Transmission Line Project

    Science.gov (United States)

    2011-03-22

    ... Bonneville Power Administration Central Ferry to Lower Monumental 500-kilovolt Transmission Line Project... the Central Ferry--Lower Monumental 500-kilovolt (kV) Transmission Line Project in Garfield, Columbia... identified in the Central Ferry--Lower Monumental 500-kV Transmission Line Project Final Environmental Impact...

  3. Modeling of overhead transmission lines for lightning overvoltage calculations

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Velasco, J.A.; Castro-Aranda, F.

    2010-10-15

    This article discussed the modelling of overhead transmission lines for lightning overvoltage calculations. Such a model must include those parts of the line that get involved when a lightning return stroke hits a wire or a tower and that have some influence on the voltage developed across insulator strings. Modelling guidelines differ depending on whether the goal is to estimate overvoltages or to determine arrester energy stresses. Modelling guidelines were summarized for each component, including shield wires and phase conductors; transmission line towers; insulators; phase voltages at the instant lightning hits the line; surge arresters; and the lightning stroke. The applied Monte Carlo procedure was summarized. For line span models, a constant-parameter model generally suffices when the goal is to calculate overvoltages across insulators or to obtain the flashover rate, but a frequency-dependent parameter model is necessary to estimate the energy discharged by arresters. The model selected for representing towers can have some influence on both flashover rates and arrester energy stresses. The representation of footing impedances is critical for calculating overvoltages and arrester energy stresses, but different modelling techniques produce significantly different results. The models are limited in that the corona effect is not included in the line models, the voltages induced by the electric and magnetic fields of lightning channels to shield wires and phase conductors are neglected, and the footing models are too simple, but they are nonetheless realistic approaches for simulating lightning effects. 2 tabs., 9 figs.

  4. The Congestion Management of Transmission Line using Bacterial Foraging Algorithm

    Directory of Open Access Journals (Sweden)

    Rasul Mokhtarpur

    2012-12-01

    Full Text Available The power systems movement to the electricity industry restructuring circumstance is done with the purpose of deformation of this industry up to elimination of exclusion and fairy competition increment and freely accessing to transmission line. But the possibility of congestion creation in the transmission line could encounter market role makers with problems such as energy price exclusion, difference in energy price at some busses and abusing of some jobbers in the market in these new systems. The study and survey in the interest of prevention and lowering of this phenomenon is done in the name of 'Congestion Management'.In this study after investigation of energy markets and the definition of congestion, local marginal price concept and ordinary method are introduced and then Bacterial Foraging Optimization Algorithm will be investigated in order to optimal determination of Local Marginal Price (LMP in the busses with purpose of production minimizing in pool market and lately it will be tested on a 24-bus standard network to formulate the optimization problem and to make it applicable.

  5. Bottlenecks reduction using superconductors in high voltage transmission lines

    Directory of Open Access Journals (Sweden)

    Daloub Labib

    2016-01-01

    Full Text Available Energy flow bottlenecks in high voltage transmission lines known as congestions are one of the challenges facing power utilities in fast developing countries. Bottlenecks occur in selected power lines when transmission systems are operated at or beyond their transfer limits. In these cases, congestions result in preventing new power supply contracts, infeasibility in existing contracts, price spike and market power abuse. The “Superconductor Technology” in electric power transmission cables has been used as a solution to solve the problem of bottlenecks in energy transmission at high voltage underground cables and overhead lines. The increase in demand on power generation and transmission happening due to fast development and linked to the intensive usage of transmission network in certain points, which in turn, lead to often frequent congestion in getting the required power across to where it is needed. In this paper, a bottleneck in high voltage double overhead transmission line with Aluminum Conductor Steel Reinforced was modeled using conductor parameters and replaced by Gap-Type Superconductor to assess the benefit of upgrading to higher temperature superconductor and obtain higher current carrying capacity. This proved to reduce the high loading of traditional aluminum conductors and allow more power transfer over the line using superconductor within the same existing right-of-way, steel towers, insulators and fittings, thus reducing the upgrade cost of building new lines.

  6. Analysis of Real-Time Monitoring Technology andDynamic Rating method of Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    徐峰; 刘聪

    2015-01-01

    Transmission line dynamic rating method as an important part of the inteligent transmission technical system can effectively solve the problem of insufficient power supply capacity of transmission lines. In this paper,the overal scheme of the dynamic rating method is briefly ilustrated. Next,transmission lines real-time monitoring technology and transmission line dynamic rating method are described respectively. Finaly,the influence of external factors on carrying capacity of transmission lines is analysed. Numerical results show that the proposed dynamic rating method is very effective.

  7. A study of electric power transmission lines for use on the lunar surface

    Science.gov (United States)

    Gordon, Lloyd B.; Gaustad, Krista L.

    1991-01-01

    Analytical models have been developed to study the operating characteristics of electrical transmission lines for use on the lunar surface. Important design considerations for a transmission line operating on the lunar surface are mass, temperature, and efficiency. Transmission line parameters which impact these considerations include voltage, power loss, and waveform. The electrical and thermal models developed are used to calculate transmission line mass, size, and temperature as a function of voltage, geometry, waveform, location, and efficiency. The analyses include ac and dc for above and below ground operation. Geometries studied include a vacuum-insulated, two-wire transmission line and a solid-dielectric insulated, coaxial transmission line. A brief discussion of design considerations and the models developed is followed by results for parameter studies for both dc and ac transmission lines.

  8. Transmission-line decelerators for atoms in high Rydberg states

    CERN Document Server

    Lancuba, P

    2014-01-01

    Beams of helium atoms in Rydberg states with principal quantum number $n=52$, and traveling with an initial speed of 1950 m/s, have been accelerated, decelerated and guided while confined in moving electric traps generated above a curved, surface-based electrical transmission line with a segmented center conductor. Experiments have been performed with atoms guided at constant speed, and with accelerations exceeding $10^7$ m/s$^2$. In each case the manipulated atoms were detected by spatially resolved, pulsed electric field ionization. The effects of tangential and centripetal accelerations on the effective trapping potentials experienced by the atoms in the decelerator have been studied, with the resulting observations highlighting contributions from the density of excited Rydberg atoms to the acceleration, deceleration and guiding efficiencies in the experiments.

  9. Transmission-line decelerators for atoms in high Rydberg states

    Science.gov (United States)

    Lancuba, P.; Hogan, S. D.

    2014-11-01

    Beams of helium atoms in Rydberg states with principal quantum number n =52 , and traveling with an initial speed of 1950 m/s, have been accelerated, decelerated, and guided while confined in moving electric traps generated above a curved, surface-based electrical transmission line with a segmented center conductor. Experiments have been performed with atoms guided at constant speed, and with accelerations exceeding 107 m /s 2. In each case, the manipulated atoms were detected by spatially resolved, pulsed electric field ionization. The effects of tangential and centripetal accelerations on the effective trapping potentials experienced by the atoms in the decelerator have been studied, with the resulting observations highlighting contributions from the density of excited Rydberg atoms to the acceleration, deceleration, and guiding efficiencies in the experiments.

  10. Tunable Transmission-Line Metamaterials Mimicking Electromagnetically Induced Transparency

    Science.gov (United States)

    Feng, T. H.; Han, H. P.

    2016-11-01

    Tunable transmission-line (TL) metamaterials mimicking electromagnetically induced transparency (EIT) have been studied. Firstly, two types of tunable TL EIT-like metamaterial, based on the double split-ring resonator (DSRR) and single split-ring resonator (SSRR), were fabricated and their transmission properties carefully compared. The results showed that the transmittance maximum was almost invariable with shift of the transparency window for the tunable DSRR-based TL EIT-like metamaterial, but for the tunable SSRR-based TL EIT-like metamaterial, the transmittance maximum gradually diminished with shift of the transparency window toward the center of the absorption band. Moreover, the reason for these different transmission properties was explored, revealing that the reduction of the transmittance maximum of the transparency window for the tunable SSRR-based TL EIT-like metamaterial is mainly due to energy loss caused by the resistance of the loaded varactor diodes.

  11. Gas insulated transmission line having low inductance intercalated sheath

    Science.gov (United States)

    Cookson, Alan H.

    1978-01-01

    A gas insulated transmission line including an outer sheath, an inner conductor disposed within the outer sheath, and an insulating gas between the inner conductor and the outer sheath. The outer sheath comprises an insulating tube having first and second ends, and having interior and exterior surfaces. A first electrically conducting foil is secured to the interior surface of the insulating tube, is spirally wound from one tube end to the second tube end, and has a plurality of overlapping turns. A second electrically conducting foil is secured to the exterior surface of the insulating tube, and is spirally wound in the opposite direction from the first electrically conducting foil. By winding the foils in opposite directions, the inductances within the intercalated sheath will cancel each other out.

  12. Wireless Sensor Network for Electric Transmission Line Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Alphenaar, Bruce

    2009-06-30

    Generally, federal agencies tasked to oversee power grid reliability are dependent on data from grid infrastructure owners and operators in order to obtain a basic level of situational awareness. Since there are many owners and operators involved in the day-to-day functioning of the power grid, the task of accessing, aggregating and analyzing grid information from these sources is not a trivial one. Seemingly basic tasks such as synchronizing data timestamps between many different data providers and sources can be difficult as evidenced during the post-event analysis of the August 2003 blackout. In this project we investigate the efficacy and cost effectiveness of deploying a network of wireless power line monitoring devices as a method of independently monitoring key parts of the power grid as a complement to the data which is currently available to federal agencies from grid system operators. Such a network is modeled on proprietary power line monitoring technologies and networks invented, developed and deployed by Genscape, a Louisville, Kentucky based real-time energy information provider. Genscape measures transmission line power flow using measurements of electromagnetic fields under overhead high voltage transmission power lines in the United States and Europe. Opportunities for optimization of the commercial power line monitoring technology were investigated in this project to enable lower power consumption, lower cost and improvements to measurement methodologies. These optimizations were performed in order to better enable the use of wireless transmission line monitors in large network deployments (perhaps covering several thousand power lines) for federal situational awareness needs. Power consumption and cost reduction were addressed by developing a power line monitor using a low power, low cost wireless telemetry platform known as the ''Mote''. Motes were first developed as smart sensor nodes in wireless mesh networking applications

  13. Cyber Risk Assessment of Transmission Lines in Smart Grids

    Directory of Open Access Journals (Sweden)

    Xuan Liu

    2015-12-01

    Full Text Available The increasing use of information technologies in power systems has increased the risk of power systems to cyber-attacks. In this paper, we assess the risk of transmission lines being overloaded due to cyber-based false data injection attacks. The cyber risk assessment is formulated as bilevel optimization problems that determine the maximum line flows under false data injection attacks. We propose efficient techniques to reduce the computation complexity of solving the bilevel problems. Specifically, primary and secondary filtering techniques are employed to identify the lines whose flows will never exceed their limits, which can significantly reduce computation burden. A special feasibility cut-based acceleration technique is introduced to further reduce the computation burden. The simulation results on the IEEE 30-bus, IEEE 118-bus, IEEE 300-bus and IEEE 2383-bus systems verify the proposed risk assessment model and the effectiveness of the proposed filtering and acceleration techniques.

  14. Development of Live-working Robot for Power Transmission Lines

    Science.gov (United States)

    Yan, Yu; Liu, Xiaqing; Ren, Chengxian; Li, Jinliang; Li, Hui

    2017-07-01

    Dream-I, the first reconfigurable live-working robot for power transmission lines successfully developed in China, has the functions of autonomous walking on lines and accurately positioning. This paper firstly described operation task and object of the robot; then designed a general platform, an insulator replacement end and a drainage plate bolt fastening end of the robot, presented a control system of the robot, and performed simulation analysis on operation plan of the robot; and finally completed electrical field withstand voltage tests in a high voltage hall as well as online test and trial on actual lines. Experimental results show that by replacing ends of manipulators, the robot can fulfill operation tasks of live replacement of suspension insulators and live drainage plate bolt fastening.

  15. Cooperative effects for Qubits in a Transmission Line: Theory

    Science.gov (United States)

    Lalumière, K.; Blais, A.; Sanders, B. C.; van Loo, A. F.; Fedorov, A.; Wallraff, A.

    2012-02-01

    Strong extinction of the transmitted power in a 1D transmission line coupled to an artificial atom has recently been achieved [1]. In contrast to the 3D case, large extinctions are made possible by the strong light-matter coupling occurring because of reduced dimensionality. Motivated by this, here we consider the situation where multiple artificial atoms (ie transmon qubits) are coupled to the 1D line. Following the work of Lehmberg for the 3D case [2], we obtain a master equation describing the dynamics of an arbitrary number of qubits coupled to the line. This master equation reveals interaction between the qubits mediated by the line. Using the input-output formalism, the model is compared to experimental results for multiple qubits coupled to the 1D line. [1] O. Astafiev et al., Science 327, 840 (2010) [2] R. H. Lehmberg. Phys. Rev. A 2, 883 (1970).

  16. Terahertz Quantum-Cascade Transmission-Line Metamaterials

    Science.gov (United States)

    Tavallaee, Amir Ali

    Terahertz quantum-cascade (QC) lasers operating at 0.6 - 5 THz (λ ˜ 60 - 500 µm) are poised to become the dominant solid-state sources of continuous-wave (cw) far-infrared radiation enabling applications in terahertz spectroscopy, imaging, and sensing. QC-lasers are the longest wavelength semiconductor laser sources in which terahertz gain is obtained from electronic intersubband radiative transitions in GaAs/AlGaAs heterostructure quantum wells. Since their invention in 2001, rapid development has enabled demonstration of cw powers greater than 100 mW. However, challenges still remain in the areas of operating temperature, laser efficiency and power, and beam quality to name a few. The highest-temperature operation of terahertz quantum-cascade lasers (200 K pulsed, 117 K cw) depends on the use of a low-loss "metal-metal" waveguide where the active gain material is sandwiched between two metal cladding layers; a technique similar, in concept, to microstrip transmission line technology at microwave frequencies. Due to the subwavelength transverse dimensions of the metal-metal waveguide, however, obtaining a directive beam pattern and efficient out-coupling of THz power is non-trivial. This thesis reports the demonstration of a one-dimensional waveguide for terahertz quantum-cascade lasers that acts as a leaky-wave antenna and tailors laser radiation in one dimension to a directional beam. This scheme adapts microwave transmission-line metamaterial concepts to a planar structure realized in terahertz metal-metal waveguide technology and is fundamentally different from distributed feedback/photonic crystal structures that work based on Bragg scattering of propagating modes. The leaky-wave metamaterial antenna operates based on a propagating mode with an effective phase index smaller than unity such that it radiates in the surface direction via a leaky-wave mechanism. Surface emission (˜ 40° from broadside) with a single directive beam (FWHM ˜ 15°) at 2.74 THz

  17. Acoustic solitons in waveguides with Helmholtz resonators: transmission line approach.

    Science.gov (United States)

    Achilleos, V; Richoux, O; Theocharis, G; Frantzeskakis, D J

    2015-02-01

    We report experimental results and study theoretically soliton formation and propagation in an air-filled acoustic waveguide side loaded with Helmholtz resonators. We propose a theoretical modeling of the system, which relies on a transmission-line approach, leading to a nonlinear dynamical lattice model. The latter allows for an analytical description of the various soliton solutions for the pressure, which are found by means of dynamical systems and multiscale expansion techniques. These solutions include Boussinesq-like and Korteweg-de Vries pulse-shaped solitons that are observed in the experiment, as well as nonlinear Schrödinger envelope solitons, that are predicted theoretically. The analytical predictions are in excellent agreement with direct numerical simulations and in qualitative agreement with the experimental observations.

  18. Tailoring of electron flow current in magnetically insulated transmission lines

    Directory of Open Access Journals (Sweden)

    J. P. Martin

    2009-03-01

    Full Text Available It is desirable to optimize (minimizing both the inductance and electron flow the magnetically insulated vacuum sections of low impedance pulsed-power drivers. The goal of low inductance is understandable from basic efficiency arguments. The goal of low electron flow results from two observations: (1 flowing electrons generally do not deliver energy to (or even reach most loads, and thus constitute a loss mechanism; (2 energetic electrons deposited in a small area can cause anode damage and anode plasma formation. Low inductance and low electron flow are competing goals; an optimized system requires a balance of the two. While magnetically insulated systems are generally forgiving, there are times when optimization is crucial. For example, in large pulsed-power drivers used to energize high energy density physics loads, the electron flow as a fraction of total current is small, but that flow often reaches the anode in relatively small regions. If the anode temperature becomes high enough to desorb gas, the resulting plasma initiates a gap closure process that can impact system performance. Magnetic-pressure driven (z pinches and material equation of state loads behave like a fixed inductor for much of the drive pulse. It is clear that neither fixed gap nor constant-impedance transmission lines are optimal for driving inductive loads. This work shows a technique for developing the optimal impedance profile for the magnetically insulated section of a high-current driver. Particle-in-cell calculations are used to validate the impedance profiles developed in a radial disk magnetically insulated transmission line geometry. The input parameters are the spacing and location of the minimum gap, the effective load inductance, and the desired electron flow profile. The radial electron flow profiles from these simulations are in good agreement with theoretical predictions when driven at relatively high voltage (i.e., V≥2  MV.

  19. Research on cost control and management in high voltage transmission line construction

    Science.gov (United States)

    Xu, Xiaobin

    2017-05-01

    Enterprises. The cost control is of vital importance to the construction enterprises. It is the key to the profitability of the transmission line project, which is related to the survival and development of the electric power construction enterprises. Due to the long construction line, complex and changeable construction terrain as well as large construction costs of transmission line, it is difficult for us to take accurate and effective cost control on the project implementation of entire transmission line. Therefore, the cost control of transmission line project is a complicated and arduous task. It is of great theoretical and practical significance to study the cost control scheme of transmission line project by a more scientific and efficient way. Based on the characteristics of the construction project of the transmission line project, this paper analyzes the construction cost structure of the transmission line project and the current cost control problem of the transmission line project, and demonstrates the necessity and feasibility of studying the cost control scheme of the transmission line project more accurately. In this way, the dynamic cycle cost control process including plan, implementation, feedback, correction, modification and re-implement is achieved to realize the accurate and effective cost control of entire electric power transmission line project.

  20. Analysis on Electric Field Around HVAC-HVDC Hybrid Transmission Lines%Analysis on Electric Field Around HVAC-HVDC Hybrid Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    LI Qian; LIU Jun-xiang; LI Hua; LIN Fu-chang

    2011-01-01

    As the transmission line corridors become more and more rare in China, it is now inevitable for people to construct HVAC-HVDC hybrid transmission lines. The research on the electric field around the transmission lines plays an important role in evaluating the electromagnetic environment nearby. However, few existing research now considered the mutual effect of HVAC-HVDC hybrid transmission lines. Thus, this research designed a program based on windows, which calculated the surface voltage gradient on the transmission lines and the electric field at ground level respectively. This research calculated the surface voltage gradient on the transmission lines by applying the improved method of successive images. For the electric field at ground level under AC transmission line, simula- tion charge method is used, while for the electric field at the ground level under DC transmission lines, deutsch as- sumption method is used. Comparing the results generated by the calculation with those in published literature, the program is reliable. Taking 500 kV transmission lines as an example, when considering the mutual effect of the HVAC-HVDC'lines, the amplitude of the surface voltage gradient will increase by about 10% and the amplitude of the electric field at ground level will increase by about 8%, making the mutual effect of the AC and DC lines unneglectable. Larger part of the electric field at ground level under hybrid lines is produced by the DC line. Thus, in order to control the electric field at ground level under hybrid lines, it should pay more attention on that produced by the DC line.

  1. Transmission line resonance technique for eccentric core optical fibers

    Science.gov (United States)

    Georgantzos, E.; Boucouvalas, A. C.

    2016-12-01

    In several cases optical fibers in telecommunications have cores of non circular geometry. Fibre optic deformations appear in optical fibres for many reasons. Optical fibre core ellipticity for example where the fibre optic core is not perfectly circular due to fibre optic manufacturing tolerances, is measured and often is a problem. Optical fibre core eccentricity, where the fibre core is not on the axis of the fibre, but it is offset by a small length. This is another issue and very important for ensuring performance low loss splices and connector losses. Both of ellipticity and eccentricity are specified in accordance to international standards for fibre optic manufacturing telecommunications grade fibres. The present paper studies ellipticity and core eccentricity specifically and presents a new method for analysing their effect. We present an extension of the transmission line technique as a means of studying such fibers and deriving necessary parameters. Conformal mapping on the other hand is a simple mathematical tool by which we can generate sets of orthogonal two-dimensional coordinate systems. Shortly a conformal map of Cartesian two-dimensional space is defined by any analytical function W(z) where z, w, are: z = x + jy, W = θ + j φ The function deriving by the conformal mapping transformation h(θ ,φ )=| ∂w/∂z | = 1/|∂z/∂w|, can be used in order to define ∇A → and ∇×A → where A → is the magnetic or electric field in the derived orthogonal coordinate system. Useful conformal maps for fiber optics applications should have the property that the equation θ(x, y) = constant, is forming closed curves in a Cartesian two-dimensional space (x,y). If θ(x, y) = constant represents a set of co-eccentric circles, we obtain the normal case of conventional fibers with circular cores. If θ(x, y) = constant represents a set of eclipses, we are have the formation of elliptic core optical fibers. If θ(x, y) = constant represents a set of

  2. Smaller-loss planar SPP transmission line than conventional microstrip in microwave frequencies.

    Science.gov (United States)

    Zhang, Hao Chi; Zhang, Qian; Liu, Jun Feng; Tang, Wenxuan; Fan, Yifeng; Cui, Tie Jun

    2016-03-17

    Transmission line is a basic component in all passive devices, integrated circuits, and systems. Microstrip is the most popular transmission line in the microwave and millimeter-wave frequencies, and has been widely used in current electronic devices, circuits, and systems. One of the important issues to be solved in such applications is the relatively large transmission loss of microstrip. Here, we propose a method to reduce the loss of microwave transmission line based on the designable wavenumber of spoof surface plasmon polaritons (SPPs). Using this characteristic, we analyze and experimentally demonstrate the low-loss feature of the SPP transmission line through the perturbation method and S-parameter measurements, respectively. Both simulation and experimental results show that the SPP transmission line has much smaller transmission loss than traditional microstrip with the same size in the microwave frequencies. Hence, the spoof SPP transmission line may make a big step forward in the low-loss circuits and systems.

  3. Improved Field Homogeneity for Transmission Line MRI Coils Using Series Capacitors

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Dong, Yunfeng

    2015-01-01

    High field magnetic resonance imaging (MRI) systems often use short sections of transmission lines for generating and sensing alternating magnetic fields. Due to distributed nature of transmission lines, the generated field is inhomogeneous. This work investigates the application of series capaci...... capacitors to improve the field homogeneity. The resulting magnetic field distribution is estimated analytically and evaluated numerically. The results are compared to a case of a conventional transmission line coil realization....

  4. Smaller-loss planar SPP transmission line than conventional microstrip in microwave frequencies

    OpenAIRE

    Hao Chi Zhang; Qian Zhang; Jun Feng Liu; Wenxuan Tang; Yifeng Fan; Tie Jun Cui

    2016-01-01

    Transmission line is a basic component in all passive devices, integrated circuits, and systems. Microstrip is the most popular transmission line in the microwave and millimeter-wave frequencies, and has been widely used in current electronic devices, circuits, and systems. One of the important issues to be solved in such applications is the relatively large transmission loss of microstrip. Here, we propose a method to reduce the loss of microwave transmission line based on the designable wav...

  5. Transfer Capability Enhancement of Transmission Line using Static Synchronous Compensator (STATCOM)

    OpenAIRE

    Arti Pateriya,Nitin Saxena ,Manoj Tiwari

    2012-01-01

    Growth of complex electrical power networks introduces lack of controllability of active and reactive power flow in energies networks Power flow control in an existing long transmission line, plays an important role in power system area. This paper employs the shunt connected compensation STATCOM based FACTS devices for the control of voltage and the power flow in long distance transmission line. The proposed device is used in different locations of transmission line and also deals with deter...

  6. Transfer Capability Enhancement of Transmission Line using Static Synchronous Compensator (STATCOM)

    OpenAIRE

    Arti Pateriya; Nitin Saxena; Manoj Tiwari

    2014-01-01

    Growth of complex electrical power networks introduces lack of controllability of active and reactive power flow in energies networks Power flow control in an existing long transmission line, plays an important role in power system area. This paper employs the shunt connected compensation STATCOM based FACTS devices for the control of voltage and the power flow in long distance transmission line. The proposed device is used in different locations of transmission line and also deals with deter...

  7. Design and simulation of on-chip lossy transmission line pairs

    OpenAIRE

    Demeester, Thomas; De Zutter, Daniël

    2008-01-01

    A quasi-TM reciprocity based multi-conductor transmission line model is used to investigate the influence of the geometry on the performance of on-chip transmission line pairs for high-frequency differential signal transmission. It is shown that both the knowledge of the fundamental transmission line modes and of the internal impedance of both connected circuits, are essential for a good design.

  8. Overhead Transmission Lines Deicing under Different Incentive Displacement

    Directory of Open Access Journals (Sweden)

    Qing He

    2014-01-01

    Full Text Available Overhead transmission line icing is one of the main factors affecting safety and reliability of power grid. This paper proposed an excitation deicing method of iced wire and theoretically revealed the ice removal mechanism under displacement excitation conditions, by taking the LGJ-70/10 glaze icing wire as the 3D model and analyzing and studying its dynamic response under the effect of displacement excitation. The simulation results show that the stress of wire icing area is enlarged with the increase of excitation displacement and frequency. Through the comparison of the compression strength experimental results on a series of different iced wires in low temperature environment, the authors found out that the stress generated from the wire icing area is greater than the crushing strength of the ice within the scope of the calculation parameters, which proved the validity and the feasibility of the method, and finally the suitable excitation displacement is determined. Following studies show that, as far as possible, it is necessary to reduce the incentive displacement and also to select the appropriate constraint length in order to avoid the line jumping that may be caused by large span ice shedding.

  9. Wild Horse 69-kV transmission line environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    Hill County Electric Cooperative Inc. (Hill County) proposes to construct and operate a 69-kV transmission line from its North Gildford Substation in Montana north to the Canadian border. A vicinity project area map is enclosed as a figure. TransCanada Power Corporation (TCP), a Canadian power-marketing company, will own and construct the connecting 69-kV line from the international border to Express Pipeline`s pump station at Wild Horse, Alberta. This Environmental Assessment is prepared for the Department of Energy (DOE) as lead federal agency to comply with the requirements of the National Environmental Policy Act (NEPA), as part of DOE`s review and approval process of the applications filed by Hill County for a DOE Presidential Permit and License to Export Electricity to a foreign country. The purpose of the proposed line is to supply electric energy to a crude oil pump station in Canada, owned by Express Pipeline Ltd. (Express). The pipeline would transport Canadian-produced oil from Hardisty, Alberta, Canada, to Caster, Wyoming. The Express Pipeline is scheduled to be constructed in 1996--97 and will supply crude oil to refineries in Wyoming and the midwest.

  10. Study of the cavity-magnon-polariton transmission line shape

    Science.gov (United States)

    Harder, Michael; Bai, LiHui; Match, Christophe; Sirker, Jesko; Hu, CanMing

    2016-11-01

    We experimentally and theoretically investigate the microwave transmission line shape of the cavity-magnon-polariton (CMP) created by inserting a low damping magnetic insulator into a high quality 3D microwave cavity. While fixed field measurements are found to have the expected Lorentzian characteristic, at fixed frequencies the field swept line shape is in general asymmetric. Such fixed frequency measurements demonstrate that microwave transmission can be used to access magnetic characteristics of the CMP, such as the field line width Δ H. By developing an effective oscillator model of the microwave transmission we show that these line shape features are general characteristics of harmonic coupling. At the same time, at the classical level the underlying physical mechanism of the CMP is electrodynamic phase correlation and a second model based on this principle also accurately reproduces the experimental line shape features. In order to understand the microscopic origin of the effective coupled oscillator model and to allow for future studies of CMP phenomena to extend into the quantum regime, we develop a third, microscopic description, based on a Green's function formalism. Using this method we calculate the transmission spectra and find good agreement with the experimental results.

  11. Transmission Line Analogy for Relativistic Poynting-Flux Jets

    CERN Document Server

    Lovelace, R V E

    2012-01-01

    Radio emission, polarization, and Faraday rotation maps of the radio jet of the galaxy 3C 303 have shown that one knot of this jet carries a {\\it galactic}-scale electric current and that it is magnetically dominated. We develop the theory of magnetically dominated or Poynting-flux jets by making an analogy of a Poynting jet with a transmission line or waveguide carrying a net current and having a potential drop across it (from the jet's axis to its radius) and a definite impedance which we derive. Time-dependent but not necessarily small perturbations of a Poynting-flux jet are described by the "telegrapher's equations." These predict the propagation speed of disturbances and the effective wave impedance for forward and backward propagating wave components. A localized disturbance of a Poynting jet gives rise to localized dissipation in the jet which may explain the enhanced synchrotron radiation in the knots of the 3C 303 jet, and also in the apparently stationary knot HST-1 in the jet near the nucleus of t...

  12. Precision electron flow measurements in a disk transmission line.

    Energy Technology Data Exchange (ETDEWEB)

    Clark, Waylon T.; Pelock, Michael D.; Martin, Jeremy Paul; Jackson, Daniel Peter Jr.; Savage, Mark Edward; Stoltzfus, Brian Scott; Mendel, Clifford Will, Jr.; Pointon, Timothy David

    2008-01-01

    An analytic model for electron flow in a system driving a fixed inductive load is described and evaluated with particle in cell simulations. The simple model allows determining the impedance profile for a magnetically insulated transmission line given the minimum gap desired, and the lumped inductance inside the transition to the minimum gap. The model allows specifying the relative electron flow along the power flow direction, including cases where the fractional electron flow decreases in the power flow direction. The electrons are able to return to the cathode because they gain energy from the temporally rising magnetic field. The simulations were done with small cell size to reduce numerical heating. An experiment to compare electron flow to the simulations was done. The measured electron flow is {approx}33% of the value from the simulations. The discrepancy is assumed to be due to a reversed electric field at the cathode because of the inductive load and falling electron drift velocity in the power flow direction. The simulations constrain the cathode electric field to zero, which gives the highest possible electron flow.

  13. Radial transmission line analysis of multi-layer structures

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, H.; Hammons, L.

    2011-03-28

    The analysis of multi-layer beam tubes is a standard problem and involves axially propagating waves. This treatment is ill suited to a short multi-layer structure such as the present example of a ferrite covered ceramic break in the beam tube at the ERL photo-cathode electron gun. This paper demonstrates that such structure can better be treated by radial wave propagation. The theoretical method is presented and numerical results are compared with measured network analyser data and Microwave Studio generated simulations. The results confirm the concept of radial transmission lines as a valid analytical method. An Energy Recovery Linac (ERL) is being constructed at this laboratory for the purpose of research towards an envisioned Electron Ion Collider. One of the pertinent topics is damping of Higher Order Modes (HOM). In this ERL, the damping is provided by ferrite absorbers in the beam tube. A modified version thereof, a ceramic break surrounded by ferrite, is planed for the superconducting electron gun. The damper here is located at room temperature just outside of the gun. If used in a cavity chain, the ceramic break is in the vacuum tube at helium temperature whereas the ferrite is moved into the cryostat insulating vacuum allowing higher temperatures. The general properties of the ferrite HOM dampers have been published but are more detailed in this paper.

  14. Modeling of unusual nonlinear behaviors in superconducting microstrip transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Javadzadeh, S. Mohammad Hassan, E-mail: smh_javadzadeh@ee.sharif.edu [School of Electrical Engineering, Sharif University of Technology, P.O. Box 11365-9363, Tehran (Iran, Islamic Republic of); Farzaneh, Forouhar; Fardmanesh, Mehdi [School of Electrical Engineering, Sharif University of Technology, P.O. Box 11365-9363, Tehran (Iran, Islamic Republic of)

    2013-03-15

    Highlights: ► Avoiding of considering just quadratic or modulus nonlinearity. ► Proposing a nonlinear model to predict unusual nonlinear behaviors at low temperatures. ► Description of temperature dependency of nonlinear behaviors in superconducting lines. ► Analytical formulation for each parameter in our proposed model. ► Obtaining very good results which shows this model can predict unusual nonlinear behavior. -- Abstract: There are unusual nonlinear behaviors in superconducting materials, especially at low temperatures. This paper describes the procedure to reliably predict this nonlinearity in superconducting microstrip transmission lines (SMTLs). An accurate nonlinear distributed circuit model, based on simultaneously considering of both quadratic and modulus nonlinearity dependences, is proposed. All parameters of the equivalent circuit can be calculated analytically using proposed closed-form expressions. A numerical method based on Harmonic Balance approach is used to predict nonlinear phenomena like intermodulation distortions and third harmonic generations. Nonlinear analyses of the SMTLs at the different temperatures and the input powers have been presented. This proposed model can describe the unusual behaviors of the nonlinearity at low temperatures, which are frequently observed in the SMTLs.

  15. Evaluation of Fibre Lifetime in Optical Ground Wire Transmission Lines

    Science.gov (United States)

    Grunvalds, R.; Ciekurs, A.; Porins, J.; Supe, A.

    2017-06-01

    In the research, measurements of polarisation mode dispersion of two OPGWs (optical ground wire transmission lines), in total four fibres, have been carried out, and the expected lifetime of the infrastructure has been assessed on the basis of these measurements. The cables under consideration were installed in 1995 and 2011, respectively. Measurements have shown that polarisation mode dispersion values for cable installed in 1995 are four times higher than that for cable installed in 2011, which could mainly be explained by technological differences in fibre production and lower fibre polarisation mode dispersion requirements in 1995 due to lack of high-speed (over 10 Gbit/s) optical transmission systems. The calculation methodology of non-refusal work and refusal probabilities, using the measured polarisation mode dispersion parameters, is proposed in the paper. Based on reliability calculations, the expected lifetime is then predicted, showing that all measured fibres most likely will be operational within minimum theoretical service life of 25 years accepted by the industry.

  16. Optimal Value of Series Capacitors for Uniform Field Distribution in Transmission Line MRI Coils

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy

    2016-01-01

    Transmission lines are often used as coils in high field magnetic resonance imaging (MRI). Due to the distributed nature of transmission lines, coils based on them produce inhomogeneous field. This work investigates application of series capacitors to improve field homogeneity along the coil....... The equations for optimal values of evenly distributed capacitors are derived and expressed in terms of the implemented transmission line parameters.The achieved magnetic field homogeneity is estimated under quasistatic approximation and compared to the regular transmission line resonator. Finally, a more...... practical case of a microstrip line coil with two series capacitors is considered....

  17. Transmission Lines or Poles, Electric, Electric Transmission Lines in Bacon County, GA, Published in 2000, 1:4800 (1in=400ft) scale, Southern Georgia Regional Commission.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Hardcopy Maps information as of 2000. It...

  18. Transmission Lines or Poles, Electric, Transmission_lines, Published in 2006, 1:600 (1in=50ft) scale, Buffalo County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, published at 1:600 (1in=50ft) scale, was produced all or in part from Orthoimagery information as of 2006. It is...

  19. Transmission Lines or Poles, Electric, Major power transmission lines. Extracted from 1992 U.S. Census Bureau TIGER/Line files., Published in 1992, Arizona State Land Department.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, was produced all or in part from Road Centerline Files information as of 1992. It is described as 'Major power...

  20. Transmission Lines or Poles, Electric, Electric Transmission Lines in Coffee County, GA, Published in 2000, 1:4800 (1in=400ft) scale, Southern Georgia Regional Commission.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Hardcopy Maps information as of 2000. It...

  1. Recent progress of the improved magnetically insulated transmission line oscillator.

    Science.gov (United States)

    Fan, Yu-Wei; Zhong, Hui-Huang; Li, Zhi-Qiang; Shu, Ting; Zhang, Jian-De; Liu, Jin-Liang; Yang, Jian-Hua; Zhang, Jun; Yuan, Cheng-Wei; Luo, Ling

    2008-03-01

    The improved magnetically insulated transmission line oscillator (MILO) is a gigawatt-class L-band high power microwave tube driven by a 550 kV, 57 kA, 50 ns electron beam. It has allowed us to generate 2.4 GW pulse of 22 ns duration. The recent progress of the improved MILO is presented in this paper. First, a field shaper cathode is introduced into the improved MILO to avoid the cathode flares in the triple point region. The experimental results show that the cathode flares are avoided, so the lifetime of the velvet cathode is longer than that of the taper cathode. Furthermore, the shot-to-shot reproducibility is better than that of the taper cathode. Second, In order to prolong the pulse duration and increase the radiated microwave power, a self-built 600 kV, 10 Omega, 80 ns pulser: SPARK-03 is employed to drive the improved MILO. Simulation and experimental investigation are performed. In simulation, when the improved MILO is driven by a 600 kV, 57 kA electron beam, high-power microwave is generated with output power of 4.15 GW, frequency of 1.76 GHz, and relevant power conversion efficiency of 12.0%. In experiments, when the diode voltage is 550 kV and current is 54 kA, the measured results are that the radiated microwave power is above 3.1 GW, the pulse duration is above 40 ns, the microwave frequency is about 1.755 GHz, and the power conversion efficiency is about 10.4%.

  2. Extragalactic circuits, transmission lines, and CR particle acceleration

    Science.gov (United States)

    Kronberg, Philipp P.; Lovelace, Richard V. E.

    2015-08-01

    A non-negligible fraction of a Supermassive Black Hole's (SMBH) rest mass energy gets transported into extragalactic space by a remarkable process in jets which are incompletely understood. What are the physical processes which transport this energy? It is likely that the energy flows electromagnetically, rather than via a particle beam flux. The deduced electromagnetic fields may produce particles of energy as high as ˜ 1020 eV. The energetics of SMBH accretion disk models and the electromagnetic energy transfer imply that a SMBH should generate a 1018 - 1019 Ampères current close to the black hole and its accretion disk. We describe the so far best observation-based estimate of the magnitude of the current flow along the axis of the jet extending from the nucleus of the active galaxy in 3C303. The current is measured to be I ˜ 1018 Ampères at ˜ 40 kpc away from the AGN. This indicates that organised current flow remains intact over multi-kpc distances. The electric current I transports electromagnetic power into free space, P = I2Z, where Z ˜ 30 Ohms is related to the impedance of free space, and this points to the existence of cosmic electric circuit. The associated electric potential drop, V = IZ, is of the order of that required to generate Ultra High Energy Cosmic Rays (UHECR). We also explore further implications, including disruption/deflection of the power flow and also why such measurements, exemplified by those on 3C303, are currently very difficult to make and to unambiguously interpret. This naturally leads to the topic of how such measurements can be extended and improved in the future. We describe the analogy of electromagnetically dominated jets with transmission lines. High powered jets in vacuo can be understood by approximate analogy with a waveguide. The importance of inductance, impedance, and other laboratory electrical concepts are discussed in this context.

  3. Extragalactic circuits, transmission lines, and CR particle acceleration

    Directory of Open Access Journals (Sweden)

    Kronberg Philipp P.

    2015-01-01

    Full Text Available A non-negligible fraction of a Supermassive Black Hole's (SMBH rest mass energy gets transported into extragalactic space by a remarkable process in jets which are incompletely understood. What are the physical processes which transport this energy? It is likely that the energy flows electromagnetically, rather than via a particle beam flux. The deduced electromagnetic fields may produce particles of energy as high as ∼ 1020 eV. The energetics of SMBH accretion disk models and the electromagnetic energy transfer imply that a SMBH should generate a 1018 − 1019 Ampères current close to the black hole and its accretion disk. We describe the so far best observation-based estimate of the magnitude of the current flow along the axis of the jet extending from the nucleus of the active galaxy in 3C303. The current is measured to be I ∼ 1018 Ampères at ∼ 40 kpc away from the AGN. This indicates that organised current flow remains intact over multi-kpc distances. The electric current I transports electromagnetic power into free space, P = I2Z, where Z ∼ 30 Ohms is related to the impedance of free space, and this points to the existence of cosmic electric circuit. The associated electric potential drop, V = IZ, is of the order of that required to generate Ultra High Energy Cosmic Rays (UHECR. We also explore further implications, including disruption/deflection of the power flow and also why such measurements, exemplified by those on 3C303, are currently very difficult to make and to unambiguously interpret. This naturally leads to the topic of how such measurements can be extended and improved in the future. We describe the analogy of electromagnetically dominated jets with transmission lines. High powered jets in vacuo can be understood by approximate analogy with a waveguide. The importance of inductance, impedance, and other laboratory electrical concepts are discussed in this context.

  4. Structural health monitoring of compression connectors for overhead transmission lines

    Science.gov (United States)

    Wang, Hong; Wang, Jy-An John; Swindeman, Joseph P.; Ren, Fei; Chan, John

    2017-04-01

    Two-stage aluminum conductor steel-reinforced (ACSR) compression connectors are extensively used in US overhead transmission lines. The connectors are made by crimping a steel sleeve onto a steel core and an aluminum sleeve over electrical conducting aluminum strands. The connectors are designed to operate at temperatures up to 125°C, but their performance is increasingly degrading because of overloading of lines. Currently, electric utilities conduct routine line inspections using thermal and electrical measurements, but these methods do not provide information about the structural integrity of connectors. In this work, structural health monitoring (SHM) of compression connectors was studied using electromechanical impedance (EMI) analysis. Lead zirconate titanate (PZT)-5A was identified as a smart material for SHM. A flexible high-temperature bonding layer was used to address challenges in PZT integration due to a significant difference in the coefficients of thermal expansion of PZT and the aluminum substrate. The steel joint on the steel core was investigated because it is responsible for the ultimate tensile strength of the connector. Tensile testing was used to induce structural damage to the joint, or steel core pullout, and thermal cycling introduced additional structural perturbations. EMI measurements were conducted between the tests. The root mean square deviation (RMSD) of EMI was identified as a damage index. The use of steel joints has been shown to enable SHM under simulated conditions. The EMI signature is sensitive to variations in structural conditions. RMSD can be correlated to the structural health of a connector and has potential for use in the SHM and structural integrity evaluation.

  5. The Issues of Reactive Power Compensation in High-voltage Transmission Lines

    Directory of Open Access Journals (Sweden)

    Zbigniew Lubośny

    2015-06-01

    Full Text Available This paper discusses the selection of compensation shunt reactors for a double-circuit 400 kV transmission line using the example of the newly built Elk Bis – Alytus transmission line. The analysis takes into account various conditions of the power system. The published results relate to voltage levels in steady states and during switching processes and short circuits.

  6. 49 CFR 192.715 - Transmission lines: Permanent field repair of welds.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Permanent field repair of... § 192.715 Transmission lines: Permanent field repair of welds. Each weld that is unacceptable under § 192.241(c) must be repaired as follows: (a) If it is feasible to take the segment of transmission...

  7. 49 CFR 236.73 - Open-wire transmission line; clearance to other circuits.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Open-wire transmission line; clearance to other... line; clearance to other circuits. Open-wire transmission line operating at voltage of 750 volts or... THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS,...

  8. 49 CFR 192.711 - Transmission lines: General requirements for repair procedures.

    Science.gov (United States)

    2010-10-01

    ... Maintenance § 192.711 Transmission lines: General requirements for repair procedures. (a) Temporary repairs... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: General requirements for..., imperfection, or damage that impairs its serviceability is found in a segment of steel transmission...

  9. 78 FR 76140 - Extension of Public Comment Period for the Champlain Hudson Power Express Transmission Line...

    Science.gov (United States)

    2013-12-16

    ... Extension of Public Comment Period for the Champlain Hudson Power Express Transmission Line Project Draft... Hudson Power Express Transmission Line Project Draft Environmental Impact Statement (DOE/EIS-0447). The... permit to the Applicant, Champlain Hudson Power Express, Inc. (CHPEI), to construct, operate,...

  10. A Complex Frequency Method for A Loaded Resonant Cavity of Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    LIANGChanghong; LILong; SUTao; FANShengcai

    2004-01-01

    A complex frequency method for analyzing a loaded resonant cavity of transmission lines is presented in this paper. A sub-resonance system theory is used to treat the various loaded transmission lines cavity more effectively. Some practice examples are given to illustrate the application and validity of the proposed approach in this paper.

  11. 78 FR 57372 - Northern Pass Transmission Line Project Environmental Impact Statement: Announcement of Change in...

    Science.gov (United States)

    2013-09-18

    ... Northern Pass Transmission Line Project Environmental Impact Statement: Announcement of Change in Public... amended Notice of Intent (NOI) to modify the scope of the Northern Pass Transmission Line Project... previously announced this change in public meeting location on both the Northern Pass EIS Web site at...

  12. Explanation of the inverse Doppler effect observed in nonlinear transmission lines.

    Science.gov (United States)

    Kozyrev, Alexander B; van der Weide, Daniel W

    2005-05-27

    The theory of the inverse Doppler effect recently observed in magnetic nonlinear transmission lines is developed. We explain the crucial role of the backward spatial harmonic in the occurrence of an inverse Doppler effect and draw analogies of the magnetic nonlinear transmission line to the backward wave oscillator.

  13. Transfer Capability Enhancement of Transmission Line using Static Synchronous Compensator (STATCOM

    Directory of Open Access Journals (Sweden)

    Arti Pateriya

    2014-12-01

    Full Text Available Growth of complex electrical power networks introduces lack of controllability of active and reactive power flow in energies networks Power flow control in an existing long transmission line, plays an important role in power system area. This paper employs the shunt connected compensation STATCOM based FACTS devices for the control of voltage and the power flow in long distance transmission line. The proposed device is used in different locations of transmission line and also deals with determination of the optimal location of shunt flexible A.C. transmission line (FACTS devices for a long transmission line for voltage and power transfer improvement. The results also show the line loading and system initial operating conditions. In this paper the two machine 4-bus test system is simulated using MATLAB Simulink environment.

  14. Transfer Capability Enhancement of Transmission Line using Static Synchronous Compensator (STATCOM

    Directory of Open Access Journals (Sweden)

    Arti Pateriya,Nitin Saxena ,Manoj Tiwari

    2012-12-01

    Full Text Available Growth of complex electrical power networks introduces lack of controllability of active and reactive power flow in energies networks Power flow control in an existing long transmission line, plays an important role in power system area. This paper employs the shunt connected compensation STATCOM based FACTS devices for the control of voltage and the power flow in long distance transmission line. The proposed device is used in different locations of transmission line and also deals with determination of the optimal locationof shunt flexible a.c. transmission line (FACTS devices for a long transmission line for voltage and power transfer improvement. The results also showthe line loading and system initial operating conditions. In this paper the two machine 4-bus test system is simulated using MATLAB Simulink environment.

  15. Review and Latest Trends in Mobile Robots Used on Power Transmission Lines

    Directory of Open Access Journals (Sweden)

    Rogério Sales Gonçalves

    2013-12-01

    Full Text Available This paper presents the current state of the art in mobile robots used on power transmission lines. Many theoretical and experimental studies have been conducted in order to develop autonomous machines to travel along transmission lines to perform inspection and/or repair work. These machines can improve efficiency, reduce labour costs and are expected to reduce the risk of injury to maintenance personnel. Despite there already being a number of pieces of theoretical research and technological developments in this area, problems related to stability, ability and autonomy still exist. As such, first this paper presents the main studies already carried out and the devices generally used on power transmission lines. After the latest trends have been presented, a new idea for module robots carrying out inspections/maintenance of power transmission lines is presented. Finally, the future of mobile robots applied to power transmission lines is discussed.

  16. Millimeter-Gap Magnetically Insulated Transmission Line Power Flow Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hutsel, Brian Thomas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stoltzfus, Brian S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fowler, William E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); LeChien, Keith R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mazarakis, Michael G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Moore, James K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mulville, Thomas D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Savage, Mark E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Stygar, William A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); McKenney, John L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Peter A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); MacRunnels, Diego J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Long, Finis W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Porter, John L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    An experiment platform has been designed to study vacuum power flow in magnetically insulated transmission lines (MITLs). The platform was driven by the 400-GW Mykonos-V accelerator. The experiments conducted quantify the current loss in a millimeter-gap MITL with respect to vacuum conditions in the MITL for two different gap distances, 1.0 and 1.3 mm. The current loss for each gap was measured for three different vacuum pump down times. As a ride along experiment, multiple shots were conducted with each set of hardware to determine if there was a conditioning effect to increase current delivery on subsequent shots. The experiment results revealed large differences in performance for the 1.0 and 1.3 mm gaps. The 1.0 mm gap resulted in current loss of 40%-60% of peak current. The 1.3 mm gap resulted in current losses of less than 5% of peak current. Classical MITL models that neglect plasma expansion predict that there should be zero current loss, after magnetic insulation is established, for both of these gaps. The experiments result s indicate that the vacuum pressure or pump down time did not have a significant effect on the measured current loss at vacuum pressures between 1e-4 and 1e-5 Torr. Additionally, there was not repeatable evidence of a conditioning effect that reduced current loss for subsequent full-energy shots on a given set of hardware. It should be noted that the experiments conducted likely did not have large loss contributions due to ion emission from the anode due to the relatively small current densi-ties (25-40 kA/cm) in the MITL that limited the anode temperature rise due to ohmic heating. The results and conclusions from these experiments may have limited applicability to MITLs of high current density (>400 kA/cm) used in the convolute and load region of the Z which experience temperature increases of >400° C and generate ion emission from anode surfaces.

  17. Dynamic Model for the Z Accelerator Vacuum Section Based on Transmission Line Code%Dynamic Model for the Z Accelerator Vacuum Section Based on Transmission Line Code

    Institute of Scientific and Technical Information of China (English)

    呼义翔; 雷天时; 吴撼宇; 郭宁; 韩娟娟; 邱爱慈; 王亮平; 黄涛; 丛培天; 张信军; 李岩; 曾正中; 孙铁平

    2011-01-01

    The transmission-line-circuit model of the Z accelerator, developed originally by W. A. STYGAR, P. A. CORCORAN, et al., is revised. The revised model uses different calculations for the electron loss and flow impedance in the magnetically insulated transmission line system of the Z accelerator before and after magnetic insulation is established. By including electron pressure and zero electric field at the cathode, a closed set of equations is obtained at each time step, and dynamic shunt resistance (used to represent any electron loss to the anode) and flow impedance are solved, which have been incorporated into the transmission line code for simulations of the vacuum section in the Z accelerator. Finally, the results are discussed in comparison with earlier findings to show the effectiveness and limitations of the model.

  18. Novel Micromachined Coplanar Waveguide Transmission Lines for Application in Millimeter-Wave Circuits

    Science.gov (United States)

    Park, Jae-Hyoung; Baek, Chang-Wook; Jung, Sanghwa; Kim, Hong-Teuk; Kwon, Youngwoo; Kim, Yong-Kweon

    2000-12-01

    In this paper, novel micromachined coplanar waveguide(CPW) transmission lines for application in millimeter-wave circuits are proposed. Two types of transmission lines with the length of 1 cm are fabricated and the measured characteristics are compared with those of the conventional CPW transmission line. One is the elevated CPW(ECPW) transmission line and the other is the overlay CPW(OCPW) line. These transmission lines are composed of 3-μm-thick electroplated gold lines with overhanging parts. By elevating the metal lines from the substrate using micromachining technology, the conductor and substrate dielectric loss can be reduced and easily integrated with conventional monolithic microwave integrated circuits. Compared with the conventional CPW line showing 2.65 dB/cm insertion loss at 50 GHz, the loss can be reduced to 1.9 dB/cm and 1.25 dB/cm at 50 GHz in the case of the ECPW and OCPW transmission lines, respectively. Also, the OCPW transmission line shows that the insertion loss does not vary with the change of the characteristic impedance. As shown in the measured and simulated results, the insertion loss is maintained below 1.4 dB/cm over wide impedance ranges.

  19. Laboratory Investigation on Lightning Flashes to High Voltage Transmission Lines%Laboratory Investigation on Lightning Flashes to High Voltage Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    Thongchai Disyadej; Stanislaw Grzybowski

    2011-01-01

    This paper presents an investigation on the attractive width of high voltage transmission lines to lightning strikes. In order to design the optimal lightning protection, the estimated number of lightning flashes on the line, which is based on its attractive width, needs to be determined. The investigation was performed using experiments with model tests at the Mississippi State University High Voltage Laboratory. For laboratory experiments, a total of 2,100 negative and positive switching impulse voltages were applied to transmission line models from a conducting rod, which represented a lightning downward leader. Different tested models of transmission lines on a scale of 1:100 were used. The effects of overhead ground wires, phase conductors, tower structures, and the magnitude and polarity of lightning strokes were also studied. The attractive width increased gradually with the height of overhead ground wires and towers as well as the magnitude of the lightning stroke current. Impulse polarity had an impact on the at- tractive width, and the attractive width for negative polarity was larger than that {or positive polarity. The taller tower had more effect on flash distribution to transmission lines than the shorter one. The experimental results agree with the actual transmission line observations published in literature. The new expressions for the attractive width of transmission lines, based on the experimental results, were established. The accurate estimation of the attractive width can help electric power utilities plan transmission systems reliably and economically. The detailed description of the back- ground problem, proposed method, experimental results, and analysis are presented in this paper.

  20. TRANSIENT ANALYSIS OF TRANSMISSION LINE CIRCUITS BASED ON THE SEMIDISCRETIZATION OF TELEGRAPH EQUATIONS

    Institute of Scientific and Technical Information of China (English)

    Guo Yushun

    2001-01-01

    A new transient analysis method for the transmission line circuits is presented in this paper. Based on the semidiscretization of the telegraph equations, a discretized time domain companion models for the transmission lines which can be conveniently implemented in a general circuit simulator such as SPICE is derived. The computation required for the model is linear with time, equivalent to the recursive convolution-based method. The formulations for both single and coupled lossy transmission lines are given. Numerical experiments are carried out to demonstrate the validity of the method.

  1. STUDY OF TRANSMISSION LINES EFFECT ON THE SYSTEM OPERATIONON OF CONTINUOUS AUTOMATIC CAB SIGNALLING

    Directory of Open Access Journals (Sweden)

    O. O. Hololobova

    2014-10-01

    Full Text Available Purpose. To conduct an effect research of the electromagnetic field of high-voltage transmission lines (HVTL (750 kV, 50 Hz on the track circuits and continuous automatic cab signalling (CACS with a signal current of 50 Hz in the areas of convergence and intersection with the transmission lines and to propose possible methods to improve noise immunity of CACS. Methodology. The measurements were performed both by means of car-laboratory and directly on rail lines. During the study the electric field strength in the range of industrial frequency directly under the transmission lines and at the distance from it to the railway lines was measured, as well as the time dependence of CACS codes with signal current frequency of 50 Hz directly under the transmission lines and at a distance from it in the absence of the train and its passing. Findings. The root causes analysis of CACS faults and failures was carried out. The effect of the electromagnetic field of high-voltage transmission lines (750 kV, 50 Hz on the track circuit and CACS with signal current of 50 Hz in the areas of convergence and intersection with the transmission line was investigated. Possible methods to improve noise immunity of CACS were considered. Originality. The effect research of transmission lines (750 kV on the operation of the automatic cab signalling on spans Prishib-Burchatsk and Privolnoye-Yelizarovo, Pridneprovsk railway in places of oblique railroads crossing and transmission lines (750 kV, 50 Hz was conducted. Electric field strength in the range of industrial frequency directly under the transmission lines and at a distance from it to the railway line, as well as the time dependences of ALSN codes with signal current frequency of 50 Hz directly under the transmission lines and at a distance from it in the absence of the train and as its passing were measured. It was found that CACS codes in track circuits under transmission lines are strongly distorted, as strength

  2. Plasmonic transmission lines: from micro to nano scale with lambda/4 impedance matching.

    Science.gov (United States)

    Ginzburg, Pavel; Orenstein, Meir

    2007-05-28

    The downscaling of conventional RF transmission lines methodologies to subwavelength plasmonic circuits is discussed and demonstrated for a lambda/4 transformer impedance matching. The nano-size transformer, matching between 0.5mum and 50nm wide plasmonic transmission lines, enhances the coupling efficiency by more than 285% compared to the direct ("end fire") coupling - i.e. harvesting more than 86% of total incident power. The influence of the transverse resonances induced by the metal claddings of the input transmission line on the light harvesting is discussed as well.

  3. A Novel Design of Radio Frequency Energy Relays on Power Transmission Lines

    Directory of Open Access Journals (Sweden)

    Jin Tong

    2016-06-01

    Full Text Available In this paper, we investigate the energy problem of monitoring sensors on high-voltage power transmission lines and propose a wireless charging scheme for a Radio Frequency IDentification (RFID sensor tag to solve a commercial efficiency problem: the maintenance-caused power outage. Considering the environmental influences on power transmission lines, a self-powered wireless energy relay is designed to meet the energy requirement of the passive RFID sensor tag. The relay can obtain the electric field energy from the transmission lines and wirelessly power the RFID sensor tags around for longer operating distance. A prototype of the energy relay is built and tested on a 110 kv line. The measurement results show that the energy relay can provide stable energy even with the influences of wind, noise and power outage. To our knowledge, it is the first work to power the RFID sensor tags on power transmission lines.

  4. The wave phase velocity in superconducting transmission lines near T{sub c}

    Energy Technology Data Exchange (ETDEWEB)

    Kuzhakhmetov, A.R.; Lobov, G.D.; Shtykov, V.V.; Zhgoon, S.A. [Moscow Power Engineering Inst. (Russian Federation). Radio Engineering Dept.

    1998-06-01

    A peculiarity in behavior of electromagnetic waves phase velocity ({nu}{sub ph}), propagating in superconducting planar transmission lines, in the vicinity of the transition temperature (T{sub c}) was observed in experiment and deduced theoretically. (orig.) 5 refs.

  5. Transmission Lines or Poles, Electric, IPPCalifLine, Published in 2008, Millard County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, was produced all or in part from Other information as of 2008. It is described as 'IPPCalifLine'. Data by this...

  6. Transmission Lines or Poles, Electric, IPPMonaLine, Published in 2007, Millard County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, was produced all or in part from Other information as of 2007. It is described as 'IPPMonaLine'. Data by this...

  7. Transmission Lines or Poles, Electric, UtilityCorridor, Published in 2008, Millard County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, was produced all or in part from Other information as of 2008. It is described as 'UtilityCorridor'. Data by...

  8. MIDOT: A novel probe for monitoring high-current flat transmission lines

    Science.gov (United States)

    Omar, K.; Novac, B. M.; Graneau, N.; Senior, P.; Smith, I. R.; Sinclair, M.

    2016-12-01

    A novel inductive probe, termed MIDOT, was developed for monitoring high-current flat transmission lines. While being inexpensive the probe does not require calibration, is resistant to both shock waves and temperature variations, and it is easy to manufacture and mount. It generates strong output signals that are relatively easy to interpret and has a detection region limited to a pre-defined part of the transmission line. The theoretical background related to the MIDOT probes, together with their practical implementation in both preliminary experimentation and high-current tests, is also presented in the paper. The novel probe can be used to benchmark existing 2D numerical codes used in calculating the current distribution inside the conductors of a transmission line but can also easily detect an early movement of a transmission line component. The probe can also find other applications, such as locating the position of a pulsed current flowing through a thin wire.

  9. Research on UAV Intelligent Obstacle Avoidance Technology During Inspection of Transmission Line

    Science.gov (United States)

    Wei, Chuanhu; Zhang, Fei; Yin, Chaoyuan; Liu, Yue; Liu, Liang; Li, Zongyu; Wang, Wanguo

    Autonomous obstacle avoidance of unmanned aerial vehicle (hereinafter referred to as UAV) in electric power line inspection process has important significance for operation safety and economy for UAV intelligent inspection system of transmission line as main content of UAV intelligent inspection system on transmission line. In the paper, principles of UAV inspection obstacle avoidance technology of transmission line are introduced. UAV inspection obstacle avoidance technology based on particle swarm global optimization algorithm is proposed after common obstacle avoidance technologies are studied. Stimulation comparison is implemented with traditional UAV inspection obstacle avoidance technology which adopts artificial potential field method. Results show that UAV inspection strategy of particle swarm optimization algorithm, adopted in the paper, is prominently better than UAV inspection strategy of artificial potential field method in the aspects of obstacle avoidance effect and the ability of returning to preset inspection track after passing through the obstacle. An effective method is provided for UAV inspection obstacle avoidance of transmission line.

  10. Characterization and Analysis of A Healthy 330 Kilovolt Double Circuit Transmission Line

    Directory of Open Access Journals (Sweden)

    Onuegbu J. C.

    2013-01-01

    Full Text Available A 330KV healthy transmission line was analyzed with the aim to investigating the influence of high voltage on human being at normal regime. Some of the operating parameters of the line, namely: shock current and voltage, inductance, reactance, radio interference, electric field charge and corona effect were highlighted. The level of protection of humans and safety operation of the power system were investigated using numerical analysis. From the analysis, a healthy 330KV transmission line can generate a carrier frequency of about 85 KHz and that corona formation in double circuit power lines is slower than in single circuit lines and that step voltage is proportional to transmission line sag. Based on the results of the paper, normally operating 330KV transmission line parameters do exceed their rated values and this is not good for healthy living

  11. Brazilian production development of class 2 polymeric surge arresters for transmission line application

    Energy Technology Data Exchange (ETDEWEB)

    Dellallibera, Adriano A. [Industria Eletromecanica Balestro, Mogi Mirim, SP (Brazil)], E-mail: adrianoad@balestro.com; Andrade, Antonio Donizetti de; Bezerra, Ana Cristina Guara; Duarte, Jose Vicente Pereira; Gois, Paulo Marcio Batista; Markiewicz, Rubens Leopoldo [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil)], Emails: andonize@cemig.com.br, anacris@cemig.com.br, vicente@cemig.com.br, pgois@cemig.com.br, rlmark@cemig.com.br

    2007-07-01

    This paper shows the steeps of Brazilian class 2 ZnO lightning surge arrester development and production, aiming to attend the goal of CEMIG transmission lines performance improvement against lightning discharges action. The description of CEMIG transmission lines performance, before and after the ZnO lightning arresters installation, the necessity of use of ZnO lightning surge arrester, the prototypes manufacture, tests, problems and solutions are presented. (author)

  12. Stillbirth and residential proximity to extremely low frequency power transmission lines: a retrospective cohort study.

    Science.gov (United States)

    Auger, Nathalie; Park, Alison L; Yacouba, Soumana; Goneau, Marc; Zayed, Joseph

    2012-02-01

    The relationship between electromagnetic field exposure and stillbirth has not been evaluated. We assessed associations between residential proximity to extremely low frequency power transmission lines and stillbirth across gestational age. Data included singleton live births (N=514,826) and stillbirths (N=2033) for 1998-2007 in metropolitan areas of Québec, Canada. Using power transmission line maps, the distances between lines and residential six-digit postal codes (rule out a possible link.

  13. Large field-of-view transmission line resonator for high field MRI

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Johannesson, Kristjan Sundgaard; Boer, Vincent

    2016-01-01

    Transmission line resonators is often a preferable choice for coils in high field magnetic resonance imaging (MRI), because they provide a number of advantages over traditional loop coils. The size of such resonators, however, is limited to shorter than half a wavelength due to high standing wave....... Achieved magnetic field distribution is compared to the conventional transmission line resonator. Imaging experiments are performed using 7 Tesla MRI system. The developed resonator is useful for building coils with large field-of-view....

  14. Large field-of-view transmission line resonator for high field MRI

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Johannesson, Kristjan Sundgaard; Boer, Vincent;

    2016-01-01

    Transmission line resonators is often a preferable choice for coils in high field magnetic resonance imaging (MRI), because they provide a number of advantages over traditional loop coils. The size of such resonators, however, is limited to shorter than half a wavelength due to high standing wave....... Achieved magnetic field distribution is compared to the conventional transmission line resonator. Imaging experiments are performed using 7 Tesla MRI system. The developed resonator is useful for building coils with large field-of-view....

  15. Optimized Minimal Inductance Transmission Line Configuration for Z-Pinch Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hurricane, O

    2003-10-16

    Successful dynamic Z-pinch experiments generally require good current delivery to the target load. Power flow losses through highly inductive transmission line configurations reduce the current available to the load. In this Brief Report, a variational calculus technique is used to determine the transmission line configuration that produces the least possible inductance and therefore the best possible current delivery for Z-pinch experiments.

  16. Optimized Minimal Inductance Transmission Line Configuration for Z-Pinch Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Hurricane, O

    2003-10-16

    Successful dynamic Z-pinch experiments generally require good current delivery to the target load. Power flow losses through highly inductive transmission line configurations reduce the current available to the load. In this Brief Report, a variational calculus technique is used to determine the transmission line configuration that produces the least possible inductance and therefore the best possible current delivery for Z-pinch experiments.

  17. From devil to angel, transmission lines boost parallel computing of linear resistor networks

    CERN Document Server

    Wei, Fei

    2009-01-01

    Transmission line is always big trouble for integrated circuits designers; however, it could be of great help to the parallel computing of extremely large linear resistor networks. In this paper, we introduce the virtual transmission method (VTM), which brings virtual transmission lines into linear resistor networks to achieve distributed and asynchronous parallel computing in the virtual time domain. Numerical experiments show that VTM could be efficiently running on the 2D or 3D microprocessor with arbitrary number of cores.

  18. Analogue Hawking Radiation in a dc-SQUID Array Transmission Line

    Science.gov (United States)

    Nation, P. D.; Blencowe, M. P.; Rimberg, A. J.; Buks, E.

    2009-08-01

    We propose the use of a superconducting transmission line formed from an array of direct-current superconducting quantum interference devices for investigating analogue Hawking radiation. Biasing the array with a space-time varying flux modifies the propagation velocity of the transmission line, leading to an effective metric with a horizon. Being a fundamentally quantum mechanical device, this setup allows for investigations of quantum effects such as backreaction and analogue space-time fluctuations on the Hawking process.

  19. High precision ultrasonic guided wave technique for inspection of power transmission line

    Science.gov (United States)

    Cheng, Jun; Qiu, Jinhao; Ji, Hongli; Wang, Enrong; Takagi, Toshiyuki; Uchimoto, Tetsuya

    2017-01-01

    Due to the merits of high inspection speed and long detecting distance, Ultrasonic Guided Wave(UGW) method has been commonly applied to the on-line maintenance of power transmission line. However, the guided wave propagation in this structure is very complicated, leading to the unfavorable defect localization accuracy. Aiming at this situation, a high precision UGW technique for inspection of local surface defect in power transmission line is proposed. The technique is realized by adopting a novel segmental piezoelectric ring transducer and transducer mounting scheme, combining with the comprehensive characterization of wave propagation and circumferential defect positioning with multiple piezoelectric elements. Firstly, the propagation path of guided waves in the multi-wires of transmission line under the proposed technique condition is investigated experimentally. Next, the wave velocities are calculated by dispersion curves and experiment test respectively, and from comparing of the two results, the guided wave mode propagated in transmission line is confirmed to be F(1,1) mode. Finally, the axial and circumferential positioning of local defective wires in transmission line are both achieved, by using multiple piezoelectric elements to surround the stands and send elastic waves into every single wire. The proposed research can play a role of guiding the development of highly effective UGW method and detecting system for multi-wire transmission line.

  20. Corporate-Feed Multilayer Bow-Tie Antenna Array Design Using a Simple Transmission Line Model

    Directory of Open Access Journals (Sweden)

    S. Didouh

    2012-01-01

    Full Text Available A transmission line model is used to design corporate-fed multilayered bow-tie antennas arrays; the simulated antennas arrays are designed to resonate at the frequencies 2.4 GHz, 5 GHz, and 8 GHz corresponding to RFID, WIFI, and radars applications. The contribution of this paper consists of modeling multilayer bow-tie antenna array fed through an aperture using transmission line model. The transmission line model is simple and precise and allows taking into account the whole geometrical, electrical, and technological characteristics of the antennas arrays. The proposed transmission line model showed its interest in the design of different multilayered bow-tie antennas and predicted the correct resonance frequency for different applications in telecommunications. To validate the proposed transmission line model, the simulation results obtained are compared with those obtained by the method of moments. The results of simulations are presented and discussed. Using this transmission line approach, the resonant frequency, input impedance, and return loss can be determined simultaneously. The paper reports several simulation results that confirm the validity of the developed model. The obtained results are then presented and discussed.

  1. Design of Chebychev’s Low Pass Filters Using Nonuniform Transmission Lines

    Directory of Open Access Journals (Sweden)

    Said Attamimi

    2016-03-01

    Full Text Available Transmission lines are utilized in many applications to convey energy as well as information. Nonuniform transmission lines (NTLs are obtained through variation of the characteristic quantities along the axial direction. Such NTLs can be used to design network elements, like matching circuits, delay equalizers, filters, VLSI interconnections, etc. In this work, NTLs were analyzed with a numerical method based on the implementation of method of moment. In order to approximate the voltage and current distribution along the transmission line, a sum of basis functions with unknown amplitudes was introduced. As basis function, a constant function was used. In this work, we observed several cases such as lossless and lossy uniform transmission lines with matching and arbitrary load. These cases verified the algorithm developed in this work. The second example consists of nonuniform transmission lines in the form of abruptly changing transmission lines. This structure was used to design a Chebychev’s low pass filter. The calculated reflection and transmission factors of the filters showed some coincidences with the measurements.

  2. Electromagnetic Field Interference on Transmission Lines due to On-Board Antenna

    Directory of Open Access Journals (Sweden)

    Heekwon Lee

    2015-01-01

    Full Text Available As the available space in the board of a mobile device becomes smaller and more compact, circuit elements and transmission lines are arranged in very close proximity, especially from the antennas which are usually installed on the same board. Due to the various on-board antennas which are designed in small space, the transmission lines on the board are electromagnetically interfered, resulting in the performance degradation of the circuit. So the engineers and circuit designers should find the least interfered place for the transmission lines and components to minimize the electromagnetic interferences. This paper discusses and presents a methodology to find the least sensitive position in the induced current distribution as well as in the noise power delivered from the antenna. For this purpose some vertical, horizontal, and bent transmission lines with antenna on the same board are designed and fabricated with and without common ground, and the transferred powers to the transmission lines were measured and were also simulated using a full-wave simulator. The results predicted by the EM simulation model were successfully confirmed through the measurement of S-parameters in the experimental setup, which shows the validness of the suggested analysis method.

  3. Identification of Optimum Location of STATCOM in Transmission Line Employing RCGA Optimization Technique

    Directory of Open Access Journals (Sweden)

    A.D. Falehi

    2012-07-01

    Full Text Available This study inspects the optimum location of STATCOM device in long transmission line to acquire the maximum power system transient stability improvement. STATCOM is a kind of prominent and effective shunt FACTS device which is used in power system to enhance the power system stability and to regulate the line voltage. When it has been placed at the center point of a transmission line, play a key role in controlling the reactive power flow and enhancing the power system transient stability. The active power losses caused by transmission line resistance alter the neutral position or optimum location of STATCOM in transmission line. RCGA optimization due to have high ability to solve non-linear objective function has been implanted to identify the optimum location of STATCOM. The results of non-linear simulation under severe disturbance approve that the optimum location of STATCOM in order to access the maximum power system transient stability by reducing the active power losses approaches to midpoint of transmission line.

  4. Fractal model of lightning channel for simulating lightning strikes to transmission lines

    Institute of Scientific and Technical Information of China (English)

    HE JinLiang; ZHANG XueWei; DONG Lin; ZENG Rong; LIU ZeHong

    2009-01-01

    How to accurately evaluate the direct-strike lightning protection is one of the key issues in the design of transmission lines.In this paper, three important issues in applying the fractal simulation to the lightning protection of transmission lines were discussed, including the criteria and implementation of upward leader inception, the connection with the magnitude of lightning current, and the calculation and control of fractal dimensions.Then we conducted the simulation iterately, leading to statistical results, which indicate that even if the transmission line satisfies the perfect shielding condition, shielding failure fault remains possible.Furthermore, we calculated the shielding failure fault rates of an EHV line with different ground obliquities and distribution of strike points over the interval between two neighboring towers along a UHV-DC line to find out the weak point of transmission-line lightning protection.This work provides a promising approach for improving the lightning protection property of transmission lines by optimizing the configuration of shielding wires and phase or pole conductors.

  5. Fractal model of lightning channel for simulating lightning strikes to transmission lines

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    How to accurately evaluate the direct-strike lightning protection is one of the key issues in the design of transmission lines. In this paper, three important issues in applying the fractal simulation to the lightning protection of transmission lines were discussed, including the criteria and implementation of upward leader inception, the connection with the magnitude of lightning current, and the calculation and control of fractal dimensions. Then we conducted the simulation iterately, leading to statistical results, which indicate that even if the transmission line satisfies the perfect shielding condition, shielding failure fault remains possible. Furthermore, we calculated the shielding failure fault rates of an EHV line with different ground obliquities and distribution of strike points over the interval between two neighboring towers along a UHV-DC line to find out the weak point of transmission-line lightning protection. This work provides a promising approach for improving the lightning protection property of transmission lines by optimizing the configuration of shielding wires and phase or pole conductors.

  6. Problems and countermeasures in construction of transmission line projects in permafrost regions

    Institute of Scientific and Technical Information of China (English)

    GuoShang Wang; QiHao Yu; YanHui You; Ze Zhang; Lei Guo; ShiJun Wang; Yong Yu

    2014-01-01

    Construction of power transmission lines is becoming an important part of permafrost engineering in China. This paper reviews the construction status and problems of transmission lines in different countries, as well as corresponding solutions that would be of practical significance for sustainable engineering practices. Russia has the longest history of transmission line construction in permafrost areas, with transmission lines (mainly 220 kV and 500 kV) spanning approximately 100,000 km. However, all countries suffer from permafrost-related tower foundation stability problems caused by freez-ing-thawing hazards such as frost heave and thaw settlement, frost lifting, and harmful cryogenic phenomena. As point-line transmission line constructions, the lines, poles and towers should be reasonably selected and installed with a comprehensive consideration of frozen soil characteristics to effectively reduce the occurrence of freezing-thawing dis-asters. Reinforced concrete pile foundations are widely used in the permafrost regions, and construction in winter is also a universal practice. Moreover, facilitating engineering measures like thermosyphons are an effective way to reduce freez-ing-thawing hazards and to maintain the stability of tower foundations.

  7. Tracing overhead transmission line corridors with regard to environmental and spatial qualities

    Directory of Open Access Journals (Sweden)

    Alenka Cof

    2005-01-01

    Full Text Available The article deals with possibilities for running the proposed overhead transmission line Okroglo-Italian border. The Slovene and Italian methods are shown as methods enabling consideration of environmental and spatial impact within the process of planning overhead transmission line corridors. The Slovene method consists of analyses of attractiveness and vulnerability, whereby the first considers those functional and economic factors that affect spatial attractiveness for overhead transmission lines. Thus we can assess the level of economic and functional suitability of alternative routes of the proposed 400 kilovolt overhead transmission line from transformation station Okroglo (Slovenia to Srednje, Golo Brdo and Vrtojba, three potential contact points on the Slovene–Italian border. In accordance with stipulations of the Law on spatial management vulnerability models were prepared, which were used to simulate the development’s potential negative environmental effects and to analyse suitability, which implies harmonisation of development and protection demands. Their result is a possible corridor that can be developed without significant conflicts. The Italian procedure was developed to trace the transmission line corridor from the Slovenian border to the transformation station in Udine. It was also applied on the Slovenian side. Three groups of factors were considered in the procedure: exclusion, repulsion, and attraction. The much simpler procedure enables comparisons, since it uses the same or at least similar spatial data. In conclusion a short commentary is added about the corridor concept as a planning tool.

  8. Transmission Line Jobs and Economic Development Impact (JEDI) Model User Reference Guide

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, M.; Keyser, D.

    2013-10-01

    The Jobs and Economic Development Impact (JEDI) models, developed through the National Renewable Energy Laboratory (NREL), are freely available, user-friendly tools that estimate the potential economic impacts of constructing and operating power generation projects for a range of conventional and renewable energy technologies. The Transmission Line JEDI model can be used to field questions about the economic impacts of transmission lines in a given state, region, or local community. This Transmission Line JEDI User Reference Guide was developed to provide basic instruction on operating the model and understanding the results. This guide also provides information on the model's underlying methodology, as well as the parameters and references used to develop the cost data contained in the model.

  9. Kinetic inductance driven nanoscale 2D and 3D THz transmission lines

    Science.gov (United States)

    Mousavi, S. Hossein; Williamson, Ian A. D.; Wang, Zheng

    2016-01-01

    We examine the unusual dispersion and attenuation of transverse electromagnetic waves in the few-THz regime on nanoscale graphene and copper transmission lines. Conventionally, such propagation has been considered to be highly dispersive, due to the RC time constant-driven voltage diffusion below 1 THz and plasmonic effects at higher optical frequencies. Our numerical modeling across the microwave, THz, and optical frequency ranges reveals that the conductor kinetic inductance creates an ultra-broadband linear-dispersion and constant-attenuation region in the THz regime. This so-called LC region is an ideal characteristic that is known to be absent in macro-scale transmission lines. The kinetic-LC frequency range is dictated by the structural dimensionality and the free-carrier scattering rate of the conductor material. Moreover, up to 40x wavelength reduction is observed in graphene transmission lines. PMID:27137628

  10. Kinetic inductance driven nanoscale 2D and 3D THz transmission lines

    CERN Document Server

    Mousavi, S Hossein; Wang, Zheng

    2015-01-01

    We examine the unusual dispersion and attenuation of transverse electromagnetic waves in the few-THz regime on nanoscale graphene and copper transmission lines. Conventionally, such propagation has been considered to be highly dispersive, due to the RC-constant-driven voltage diffusion below 1THz and plasmonic effects at higher frequencies. Our numerical modelling between the microwave and optical regimes reveals that conductor kinetic inductance creates an ultra-broadband LC region. This resultant frequency-independent attenuation is an ideal characteristic that is known to be non-existent in macro-scale transmission lines. The kinetic-LC frequency range is dictated by the structural dimensionality and the free-carrier scattering rate of the conductor material. Moreover, up to 40x wavelength reduction is observed in graphene transmission lines.

  11. Fast Decoupled Power Flow for Power System with High Voltage Direct Current Transmission Line System

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2010-01-01

    Full Text Available Problem statement: High voltage direct current transmission line system has been widely applied for control power flow in power system. The power flow analysis was the one of powerful tools by which the power system equipped was analyzed both for planning and operation strategies. Approach: This study presented the method to analyze power flow of power system consisted of HVDC system. HVDC was modeled as the complex power injections. The presented complex power injected was incorporated into the existing power flow program based on fast decoupled method. The presented method was tested on the multimachine power system. Results: The transmission line loss of the system with and without HVDC was compared. Conclusion: From the simulation results, the HVDC can reduce transmission line loss of power system.

  12. Kinetic inductance driven nanoscale 2D and 3D THz transmission lines.

    Science.gov (United States)

    Mousavi, S Hossein; Williamson, Ian A D; Wang, Zheng

    2016-05-03

    We examine the unusual dispersion and attenuation of transverse electromagnetic waves in the few-THz regime on nanoscale graphene and copper transmission lines. Conventionally, such propagation has been considered to be highly dispersive, due to the RC time constant-driven voltage diffusion below 1 THz and plasmonic effects at higher optical frequencies. Our numerical modeling across the microwave, THz, and optical frequency ranges reveals that the conductor kinetic inductance creates an ultra-broadband linear-dispersion and constant-attenuation region in the THz regime. This so-called LC region is an ideal characteristic that is known to be absent in macro-scale transmission lines. The kinetic-LC frequency range is dictated by the structural dimensionality and the free-carrier scattering rate of the conductor material. Moreover, up to 40x wavelength reduction is observed in graphene transmission lines.

  13. High voltage transmission lines studies with the use of artificial intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Ekonomou, L. [A.S.PE.T.E. - School of Pedagogical and Technological Education, Department of Electrical Engineering Educators, N. Heraklion, 141 21 Athens (Greece)

    2009-12-15

    The paper presents an alternative approach for the studies of high voltage transmission lines based on artificial intelligence and more specifically artificial neural networks (ANNs). In contrast to the existing conventional-analytical techniques and simulations which are using in the calculations empirical and/or approximating equations, this approach is based only on actual field data and actual measurements. The proposed approach is applied on high voltage transmission lines in order to calculate the lightning outages, on grounding systems in order to assess the grounding resistance and on high voltage transmission lines' polluted insulators in order to estimate the critical flashover voltage. The obtained results are very close to the actual ones for all three case studies, something which clearly implies that the ANN approach is well working and has an acceptable accuracy, constituting an additional tool of electric engineers. (author)

  14. Experimental analysis of a TEM plane transmission line for DNA studies at 900 MHz EM fields

    Energy Technology Data Exchange (ETDEWEB)

    Belloni, F [Dipartimento di Fisica, Laboratorio di Elettronica Applicata e Strumentazione, LEAS INFN sez. di Lecce, Universita degli Studi di Lecce, Via Provinciale Lecce-Arnesano, CP 193, 73100 Lecce (Italy); Doria, D [Dipartimento di Fisica, Laboratorio di Elettronica Applicata e Strumentazione, LEAS INFN sez. di Lecce, Universita degli Studi di Lecce, Via Provinciale Lecce-Arnesano, CP 193, 73100 Lecce (Italy); Lorusso, A [Dipartimento di Fisica, Laboratorio di Elettronica Applicata e Strumentazione, LEAS INFN sez. di Lecce, Universita degli Studi di Lecce, Via Provinciale Lecce-Arnesano, CP 193, 73100 Lecce (Italy); Nassisi, V [Dipartimento di Fisica, Laboratorio di Elettronica Applicata e Strumentazione, LEAS INFN sez. di Lecce, Universita degli Studi di Lecce, Via Provinciale Lecce-Arnesano, CP 193, 73100 Lecce (Italy); Velardi, L [Dipartimento di Fisica, Laboratorio di Elettronica Applicata e Strumentazione, LEAS INFN sez. di Lecce, Universita degli Studi di Lecce, Via Provinciale Lecce-Arnesano, CP 193, 73100 Lecce (Italy); Alifano, P [Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Laboratorio di Microbiologia, Universita degli Studi di Lecce, Via Provinciale Lecce-Monteroni, CP 193, 73100 Lecce (Italy); Monaco, C [Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Laboratorio di Microbiologia, Universita degli Studi di Lecce, Via Provinciale Lecce-Monteroni, CP 193, 73100 Lecce (Italy); Tala, A [Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Laboratorio di Microbiologia, Universita degli Studi di Lecce, Via Provinciale Lecce-Monteroni, CP 193, 73100 Lecce (Italy); Tredici, M [Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Laboratorio di Microbiologia, Universita degli Studi di Lecce, Via Provinciale Lecce-Monteroni, CP 193, 73100 Lecce (Italy); Raino, A [Dipartimento di Fisica, INFN sez. di Bari, Universita degli Studi di Bari, Via Amendola, 173, 70126 Bari (Italy)

    2006-07-07

    A suitable plane transmission line was developed and its behaviour analysed at 900 MHz radiofrequency fields to study DNA mutability and the repair of micro-organisms. In this work, utilizing such a device, we investigated the behaviour of DNA mutability and repair of Escherichia coli strains. The transmission line was very simple and versatile in changing its characteristic resistance and field intensity by varying its sizes. In the absence of cell samples inside the transmission line, the relative modulation of the electric and/or magnetic field was {+-}31% with respect to the mean values, allowing the processing of more samples at different exposure fields in a single run. A slight decrease in spontaneous mutability to rifampicin-resistance of the E. coli JC411 strain was demonstrated in mismatch-repair proficient samples exposed to the radio-frequency fields during their growth on solid medium.

  15. Onset of dispersion in Nb microstrip transmission lines at submillimeter wave frequencies

    Science.gov (United States)

    Javadi, H. H. S.; Mcgrath, William R.; Bumble, B.; Leduc, Henry G.

    1992-01-01

    We have measured the dispersion in phase velocity of a Nb-SiO(x)-Nb microstrip transmission line resonator over a frequency range from 50 GHz to 800 GHz. A submicron Nb/Al-AlO(x)/Nb Josephson junction was used as a voltage-controlled oscillator to excite the high order modes in the resonator. The same junction is used as a direct detector resulting in a series of step-like structures in the DC current-voltage characteristic at the position of each mode frequency. The transmission line is dispersionless up to about 500 GHz where the phase velocity begins to decrease. This is well below the gap frequency f(sub g) approx. equals 700 GHz. Results agree qualitatively with the expected theoretical behavior near f(sub g). This onset of dispersion and loss in Nb transmission lines will have a significant impact on the design of submillimeter wave RF circuits.

  16. A test of a 2 Tesla superconducting transmission line magnet system

    Energy Technology Data Exchange (ETDEWEB)

    Piekarz, Henryk; Carcagno, Ruben; Claypool, Brad; Foster, George W.; Hays, Steven L.; Huang, Yuenian; Kashikhin, Vladimir; Malamud, Ernest; Mazur, Peter O.; Nehring,; Oleck, Andrew; Rabehl, Roger; Schlabach, Phil; Sylvester, Cosmore; Velev, Gueorgui; Volk, James; /Fermilab; Wake, Masayoshi; /KEK, Tsukuba

    2005-09-01

    Superconducting transmission line magnet test system for an injector accelerator of a staged VLHC proton-proton colliding beam accelerator has been built and operated at Fermilab. The 1.5 m long, twin-aperture, combined function dipole magnet of 2 Tesla field is excited by a single turn 100 kA transmission line superconductor. The 100 kA dc current is generated using dc-dc switching converters powered by a bulk 240 kW supply. A pair of horizontally placed conventional leads facilitates transfer of this current to the magnet transmission line superconductor operating at liquid helium temperature. Fabrication of magnet components and magnet assembly work are described. The magnet test system and its operation are presented, and the performance is summarized.

  17. Enhanced coherent OTDR for long span optical transmission lines containing optical fiber amplifiers

    Science.gov (United States)

    Furukawa, Shin-Ichi; Tanaka, Kuniaki; Koyamada, Yahei; Sumida, Masatoyo

    1995-05-01

    We have newly constructed an enhanced coherent optical time domain reflectometer (C-OTDR) for use in testing optical cable spans in transmission lines containing erbium-doped fiber amplifiers (EDFA's), which is based on heterodyne detection using acousto-optic (AO) switches. In order to avoid any optical surges in the EDFA's in the transmission lines, optical dummy pulses were added between the signal pulses by an AO switch to keep the probe power from the C-OTDR as uniform as possible. We achieved a large single-way dynamic range of 42 dB with 5 dBm less probe power. The measurable portion of the fiber spans was more than 80 km in optical transmission lines containing EDFA's. This is twice the previously reported value.

  18. Normal modes of a superconducting transmission-line resonator with embedded lumped element circuit components

    Science.gov (United States)

    Mortensen, Henrik Lund; Mølmer, Klaus; Andersen, Christian Kraglund

    2016-11-01

    We present a method to identify the coupled, normal modes of a superconducting transmission line with an embedded lumped element circuit. We evaluate the effective transmission-line nonlinearities in the case of Kerr-like Josephson interactions in the circuit and in the case where the embedded circuit constitutes a qubit degree of freedom, which is Rabi coupled to the field in the transmission line. Our theory quantitatively accounts for the very high and positive Kerr nonlinearities observed in a recent experiment [M. Rehák, P. Neilinger, M. Grajcar, G. Oelsner, U. Hübner, E. Il'ichev, and H.-G. Meyer, Appl. Phys. Lett. 104, 162604 (2014), 10.1063/1.4873719], and we can evaluate the accomplishments of modified versions of the experimental circuit.

  19. Digital simulation studies on long transmission line protection based on balance of energy

    Institute of Scientific and Technical Information of China (English)

    文明浩; 陈德树; 尹项根

    2001-01-01

    The protection based balance of energy is a new technique specially proposed for long transmission lines. This technique depends upon the calculation of net energy into the transmission line by two independent methods and comparing them to indicate healthy and faulty conditions. In order to study the performance and feasibility of the protection based on balance of energy, the new protection has been extensively tested by using EMTP on a long transmission line with various configurations and operating conditions (including single pole line, double circuit lines and two-phase operation). The results calculated by EMTP show that under any condition of a power system, the proposed technique has excellent performance,the viability even for high resistance ground faults and a short operation time.

  20. Non-Linear Transmission Line (NLTL) Microwave Source Lecture Notes the United States Particle Accelerator School

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Steven J. [Los Alamos National Laboratory; Carlsten, Bruce E. [Los Alamos National Laboratory

    2012-06-26

    We will quickly go through the history of the non-linear transmission lines (NLTLs). We will describe how they work, how they are modeled and how they are designed. Note that the field of high power, NLTL microwave sources is still under development, so this is just a snap shot of their current state. Topics discussed are: (1) Introduction to solitons and the KdV equation; (2) The lumped element non-linear transmission line; (3) Solution of the KdV equation; (4) Non-linear transmission lines at microwave frequencies; (5) Numerical methods for NLTL analysis; (6) Unipolar versus bipolar input; (7) High power NLTL pioneers; (8) Resistive versus reactive load; (9) Non-lineaer dielectrics; and (10) Effect of losses.

  1. Competition Mechanism of Lightning Upward Leaders Issued from UHVDC Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    SHI Wei; LI Qingmin; LU Xinchang; ZOU Liang; SUN Qiuqin

    2012-01-01

    Research on the lightning shielding failure characteristics of UHVDC transmission lines is important for adequate transmission line protection and safe operation of a power grid. Focusing the competition characteristics of upward leaders in the lightning attachment process, this work provides technical reference for efficient evaluations of lightning shielding failures and reliable lightning protection designs of UHVDC transmission lines. The charge simulation method is employed to calculate electric field distributions. Based on the calculation and some data obtained by recent long-gap discharge and lightning observations, the effect of several upward leaders starting from UHVDC transmission lines on lightning attachment processes is studied by numerical simulation. The results show that the upward leader inception is delayed, the propagation velocity is smaller, and the propagation direction of the upward leader is changed with interaction among all upward leaders, which influences the selection of lightning striking point. Therefore, in order to improve the accuracy of calculating the lightning shielding failure rate of UHVDC transmission lines, the interaction characteristics of upward leaders should be taken into account . In addition, an analysis of the influence of operating voltage and the protection angle of UHVDC transmission lines based on competition mechanism of upward leaders is made. It is found that the existence of operating voltage mainly affects the ability of the conductor and the overhead ground wire at the same side to incept upward leaders, while the protection angle mainly affects the position of the "starting points" of upward leaders. The results indicate that positive polar conductors should be installed closer to hillsides and the negative protection angle of towers is suggested.

  2. Design of 1000-kV AC Single-Circuit Overhead Transmission Line

    Institute of Scientific and Technical Information of China (English)

    Li

    2010-01-01

    The UHVAC 1 000-kV transmission system is so far the one with the most advanced transmission technique applied and highest operation voltage. There are no guidelines or standards available for the design of 1 000-kV overhead transmission line in China. Study on key technologies and design schemes shall be carried out to ascertain the technical principles and construction standards for project construction, which are presented in this paper based on the Southeast Shanxi-Nanyang-Jingmen test and demonstration transmission line. A comparison and analysis of technical data and economic indices between UHV line and other lines are also described.

  3. Study on the principle of intelligent helmet's electric alarm device in transmission line

    Science.gov (United States)

    Zhang, Zehao; Peng, Lin; Bao, Xingchuan; Zhu, Liang; Wang, He; Zhou, Qiang

    2017-08-01

    This thesis made study on the Principle of Intelligent Helmet's Electric Alarm Device in Transmission Line. Based on the simulation analysis of the electric field strength and electric field characteristics of three-phase 10kV transmission line, this thesis put forward the calculation method of the electric alarm distance by developing a calculation model, and then explains proof of the accuracy of intelligent helmet's electric alarm and discusses its theoretical basis. At last, the theoretical analysis' correctness and the measurement's accuracy of the intelligent helmet's electric alarm device is proved by tests.

  4. Using technique vibration diagnostics for assessing the quality of power transmission line supports repairs

    Directory of Open Access Journals (Sweden)

    Cherpakov Aleksander

    2017-01-01

    Full Text Available The considered method for assessing the quality of the repair work to restore the rack supports of transmission lines is based on the method of vibration diagnostics. Power transmission line supports with a symmetrical destruction of the protective layer of concrete in the ground in violation of the construction section were chosen as an object. Finite element modelling package Ansys was used in assessing the quality of repair work. The example of evaluating the quality of repair using the relative adhesion defective area design criteria in the analysis of natural vibration frequencies is given.

  5. A microwave transmission-line network guiding electromagnetic fields through a dense array of metallic objects

    CERN Document Server

    Alitalo, Pekka; Vehmas, Joni; Tretyakov, Sergei

    2008-01-01

    We present measurements of a transmission-line network, designed for cloaking applications in the microwave region. The network is used for channelling microwave energy through an electrically dense array of metal objects, which is basically impenetrable to the impinging electromagnetic radiation. With the designed transmission-line network the waves emitted by a source placed in an air-filled waveguide, are coupled into the network and guided through the array of metallic objects. Our goal is to illustrate the simple manufacturing, assembly, and the general feasibility of these types of cloaking devices.

  6. Radiating nonuniform transmission-line systems and the partial element equivalent circuit method

    CERN Document Server

    Nitsch, Juergen; Wollenberg, Gunter

    2009-01-01

    High frequencies of densely packed modern electronic equipment turn even the smallest piece of wire into a transmission line with signal retardation, dispersion, attenuation, and distortion. In electromagnetic environments with high-power microwave or ultra-wideband sources, transmission lines pick up noise currents generated by external electromagnetic fields. These are superimposed on essential signals, the lines acting not only as receiving antennas but radiating parts of the signal energy into the environment. This book is outstanding in its originality. While many textbooks rephrase

  7. Study on Reactance Relays for Single Phase to Earth Fault on EHV Transmission Lines

    Directory of Open Access Journals (Sweden)

    Yongqing Liu

    2013-07-01

    Full Text Available Two questions about zero-sequence-reactance relay to overcome the disadvantages of high fault resistance for single phase to earth fault of high voltage transmission lines are discussed in this paper. The first question is about the phase difference between the measured zero-sequence current and voltage at fault position for un-balanced transmission lines. The second question is about the “in-phase” problem in reactance relays (or fault component reactance relays. This paper analyzes the two questions theoretically and the reactance relay is improved by a new discriminative principle. The capability against the fault resistance is largely enhanced by the improved schemes.    

  8. Robust phase-domain transmission line representation based on time-domain fitting

    Energy Technology Data Exchange (ETDEWEB)

    Nobre, Diana M.; Neves, Washington L.A. [Federal University of Campina Grande (UFCG), Electrical Engineering Department, Av Aprigio Veloso, 882 Campina Grande, PB 58.109-970 (Brazil); Boaventura, Wallace do C. [Federal University of Minas Gerais (UFMG), Electrical Engineering Department, Av Antonio Carlos, 6627 Pampulha, Belo Horizonte, MG 31.270-010 (Brazil)

    2006-05-15

    This work presents a methodology for deriving a phase-domain transmission line representation based on time-domain fitting. A polynomial matrix in the discrete-time domain describes the resulting model. The robustness of the representation, its stability and passivity, is attained by imbedding a set of constraints in the solution of the fitting equations, which are solved using quadratic programming. Results demonstrating from transient simulations the features of the derived representation are presented for the case of an asymmetric, untransposed two-phase transmission line. (author)

  9. Resonant tunneling of a wave through a structure that contains a layer with a negative refractive index

    Science.gov (United States)

    Afanas'ev, S. A.; Sementsov, D. I.; Yakimov, Ya. V.

    2016-05-01

    We have investigated the transmission ability of a layered structure the central layer of which is made of a "left-handed" material (its refractive index is negative) and is separated by two air slabs from a "right-handed" dielectric medium that surrounds the structure. We consider tunneling of energy fluxes through the structure and determine conditions for the complete (reflectionless) transmission of the power of the incident wave through it. We show that this effect is resonant and is observed when the tangential component of the wave vector of the incident wave coincides with the longitudinal wave vector of one of waveguiding eigenmodes of the left-handed layer.

  10. Coexistence of positive and negative refractive index sensitivity in the liquid-core photonic crystal fiber based plasmonic sensor.

    Science.gov (United States)

    Shuai, Binbin; Xia, Li; Liu, Deming

    2012-11-05

    We present and numerically characterize a liquid-core photonic crystal fiber based plasmonic sensor. The coupling properties and sensing performance are investigated by the finite element method. It is found that not only the plasmonic mode dispersion relation but also the fundamental mode dispersion relation is rather sensitive to the analyte refractive index (RI). The positive and negative RI sensitivity coexist in the proposed design. It features a positive RI sensitivity when the increment of the SPP mode effective index is larger than that of the fundamental mode, but the sensor shows a negative RI sensitivity once the increment of the fundamental mode gets larger. A maximum negative RI sensitivity of -5500nm/RIU (Refractive Index Unit) is achieved in the sensing range of 1.50-1.53. The effects of the structural parameters on the plasmonic excitations are also studied, with a view of tuning and optimizing the resonant spectrum.

  11. Negative refractive index of metallic cross-I-shaped pairs: origin and evolution with pair gap width.

    Science.gov (United States)

    Ma, Y G; Wang, X C; Ong, C K

    2008-07-01

    A structured composite of the negative index of refraction was fabricated by one layer of cross-I-shaped metal pairs. In this structure, the electric and magnetic inclusions were effectively integrated into one small unit. We varied the spacing of the cross pair to control the location of the magnetic resonance mode and their intercoupling with the electric mode. The frequency dependences of permittivity, permeability, and refractive indices with different gap widths of the pairs were systematically discussed by free-space measurement as well as numerical simulation. A spacing window dependent on the geometrical parameters was found in which the real part of the refractive index could have a negative value. The one-layer cross-pair pattern proposed in this work can be extended to three-dimensional structures with well-controlled interlayer coupling that will greatly facilitate the fabrication and measurement of negative-index materials in high frequencies.

  12. A cluster of many small holes with negative imaginary surface impedances may generate a negative refraction index

    Science.gov (United States)

    Alsaedi, Ahmed; Ahmad, Bashir; Challa, Durga Prasad; Kirane, Mokhtar; Sini, Mourad

    2016-09-01

    We deal with the scattering of an acoustic medium modeled by an index of refraction $n$ varying in a bounded region $\\Omega$ of $\\mathbb{R}^3$ and equal to unity outside $\\Omega$. This region is perforated with an extremely large number of small holes $D_m$'s of maximum radius $a$, $a0$ and $\\lambda_{m,0}$ being constants and eventually complex numbers. Under some natural conditions on the parameters $\\beta, t$ and $\\lambda_{m,0}$, we characterize the equivalent medium generating, approximately, the same scattered waves as the original perforated acoustic medium. We give an explicit error estimate between the scattered waves generated by the perforated medium and the equivalent one respectively, as $a \\rightarrow 0$. As applications of these results, we discuss the following findings: 1. If we choose negative valued imaginary surface impedance functions, attached to each surface of the holes, then the equivalent medium behaves as a passive acoustic medium only if it is an acoustic metamaterial with index of refraction $\\tilde{n}(x)=-n(x),\\; x \\in \\Omega$ and $\\tilde{n}(x)=1,\\; x \\in \\mathbb{R}^3\\setminus{\\overline{\\Omega}}$. This means that, with this process, we can switch the sign of the index of the refraction from positive to negative values. 2. We can choose the surface impedance functions attached to each surface of the holes so that the equivalent index of refraction $\\tilde{n}$ is $\\tilde{n}(x)=1,\\; x \\in \\mathbb{R}^3$. This means that the region $\\Omega$ modeled by the original index of refraction $n$ is approximately cloaked.

  13. Three-Dimensionally Isotropic Negative Refractive Index Materials from Block Copolymer Self-Assembled Chiral Gyroid Networks

    KAUST Repository

    Hur, Kahyun

    2011-10-17

    Metamaterials are engineered artificial materials that offer new functionalities such as super-resolution imaging and cloaking. Calculations of the photonic properties of three-dimensionally isotropic metamaterials with cubic double gyroid and alternating gyroid morphologies from block copolymer self-assembly are presented.

  14. Mechanical Implementation and Simulation of MoboLab, A Mobile Robot for Inspection of Power Transmission Lines

    OpenAIRE

    Mahmud Saadat Foumani; Mostafa Nayyerloo; Seyyed Mohammad Mehdi Yeganehparast; Alireza Barati

    2008-01-01

    This paper describes the first phase in development of a mobile robot that can navigate aerial power transmission lines completely unattended by human operator. Its ultimate purpose is to automate inspection of power transmission lines and their equipments. The authors have developed a scaled functional model of such a mobile robot with a preliminary simple computer based on-off controller. MoboLab (Mobile Laboratory) navigates a power transmission line between two strain towers. It can maneu...

  15. 75 FR 56051 - Bemidji to Grand Rapids Minnesota 230 kV Transmission Line Project

    Science.gov (United States)

    2010-09-15

    ...) transmission line between the Wilton Substation near Bemidji, Minnesota and the Boswell Substation near Grand... also proposes to modify the Wilton and Boswell substations and construct a new 115 kV breaker station... substation in the Cass Lake, Minnesota area, depending on the route alternative selected for the Project. The...

  16. 76 FR 26183 - Safety Zone; Repair of High Voltage Transmission Lines to Logan International Airport, Saugus...

    Science.gov (United States)

    2011-05-06

    ... to Logan International Airport, Saugus River, Saugus, MA AGENCY: Coast Guard, DHS. ACTION: Temporary... transmission lines to Logan Airport. This safety zone is required to provide for the safety of life on... Lines to Logan International Airport, Saugus River, Saugus, Massachusetts, in the Federal Register...

  17. 76 FR 4575 - Safety Zone; Repair of High Voltage Transmission Lines to Logan International Airport, Saugus...

    Science.gov (United States)

    2011-01-26

    ... to Logan International Airport, Saugus River, Saugus, MA AGENCY: Coast Guard, DHS. ACTION: Notice of... of high voltage transmission lines to Logan Airport. This safety zone is required to provide for the... feed Logan Airport. The safety zone will be enforced immediately before, during, and after the start...

  18. Measuring the complex permittivity tensor of uniaxial biological materials with coplanar waveguide transmission line

    Science.gov (United States)

    A simple and accurate technique is described for measuring the uniaxial permittivity tensor of biological materials with a coplanar waveguide transmission-line configuration. Permittivity tensor results are presented for several chicken and beef fresh meat samples at 2.45 GHz....

  19. Evaluation of Transmission Line Model Structures for Silicide-to-Silicon Specific Contact Resistance Extraction

    NARCIS (Netherlands)

    Stavitski, Natalie; Dal, van Mark J.H.; Lauwers, Anne; Vrancken, Christa; Kovalgin, Alexey Y.; Wolters, Rob A.M.

    2008-01-01

    In order to measure silicide-to-silicon specific contact resistance ρc, transmission line model (TLM) structures were proposed as attractive candidates for embedding in CMOS processes. We optimized TLM structures for nickel silicide and platinum silicide and evaluated them for various doping levels

  20. Efficient design of multituned transmission line NMR probes: the electrical engineering approach.

    Science.gov (United States)

    Frydel, J A; Krzystyniak, M; Pienkowski, D; Pietrzak, M; de Sousa Amadeu, N; Ratajczyk, T; Idzik, K; Gutmann, T; Tietze, D; Voigt, S; Fenn, A; Limbach, H H; Buntkowsky, G

    2011-01-01

    Transmission line-based multi-channel solid state NMR probes have many advantages regarding the cost of construction, number of RF-channels, and achievable RF-power levels. Nevertheless, these probes are only rarely employed in solid state-NMR-labs, mainly owing to the difficult experimental determination of the necessary RF-parameters. Here, the efficient design of multi-channel solid state MAS-NMR probes employing transmission line theory and modern techniques of electrical engineering is presented. As technical realization a five-channel ((1)H, (31)P, (13)C, (2)H and (15)N) probe for operation at 7 Tesla is described. This very cost efficient design goal is a multi port single coil transmission line probe based on the design developed by Schaefer and McKay. The electrical performance of the probe is determined by measuring of Scattering matrix parameters (S-parameters) in particular input/output ports. These parameters are compared to the calculated parameters of the design employing the S-matrix formalism. It is shown that the S-matrix formalism provides an excellent tool for examination of transmission line probes and thus the tool for a rational design of these probes. On the other hand, the resulting design provides excellent electrical performance. From a point of view of Nuclear Magnetic Resonance (NMR), calibration spectra of particular ports (channels) are of great importance. The estimation of the π/2 pulses length for all five NMR channels is presented.

  1. Coupling and corona effects research plan for transmission lines. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bridges, J E; Formanek, V C

    1976-06-01

    Concern has arisen over the possible effects of electric and magnetic fields produced by EHV-UHV transmission lines. Past and ongoing research concerning the electric and magnetic field effects from EHV-UHV transmission lines was reviewed as it pertains to the following areas: (1) electromagnetic interference, (2) acoustic noise, (3) generation of gaseous effluents, and (4) safety considerations of induced voltages and currents. The intent of this review was to identify the short and long range research projects required to address these areas. The research plan identifies and gives priority to twenty programs in corona and coupling effects. In the case of the corona effects, a number of programs were recommended for acoustic noise and electromagnetic interference to delineate improved power line design criteria in terms of social, meteorological, geographical and cost constraints. Only one project is recommended in the case of ozone generation, because the results of comprehensive analyses, laboratory studies and field measurements have demonstrated that power lines do not contribute significant quantities of ozone. In the case of the coupling effects, a number of programs are recommended for HVAC transmission lines to improve the theoretically developed design guidelines by considering practical constraints. For HVDC transmission lines, programs are suggested to engender a better theoretical understanding and practical measurements capability for the coupling mechanisms of the dc electric and magnetic field with nearby objects. The interrelationship of the programs and their role in a long-term research plan is also discussed.

  2. OPTIMIZATION OF TRANSIENT FEEDING TO PARALLEL-PLATE TRANSMISSION LINES FROM COAXIAL LINE

    Institute of Scientific and Technical Information of China (English)

    Tian Chunming; Wang Jianguo; Meng Fenxia; Zhang Maoyu; Ge Debiao

    2001-01-01

    The transient feeding to parallel-plate transmission lines from coaxial line is optimized by using the Finite-Difference Time-Domain (FDTD) method and a simple FDTD feed model. Observing the reflected voltages, this letter presents the optimal feeding position and ratio of width to height for a given input impedance of the coaxial line.

  3. Ground-Wave Propagation Effects on Transmission Lines through Error Images

    Directory of Open Access Journals (Sweden)

    Uribe-Campos Felipe Alejandro

    2014-07-01

    Full Text Available Electromagnetic transient calculation of overhead transmission lines is strongly influenced by the natural resistivity of the ground. This varies from 1-10K (Ω·m depending on several media factors and on the physical composition of the ground. The accuracy on the calculation of a system transient response depends in part in the ground return model, which should consider the line geometry, the electrical resistivity and the frequency dependence of the power source. Up to date, there are only a few reports on the specialized literature about analyzing the effects produced by the presence of an imperfectly conducting ground of transmission lines in a transient state. A broad range analysis of three of the most often used ground-return models for calculating electromagnetic transients of overhead transmission lines is performed in this paper. The behavior of modal propagation in ground is analyzed here into effects of first and second order. Finally, a numerical tool based on relative error images is proposed in this paper as an aid for the analyst engineer to estimate the incurred error by using approximate ground-return models when calculating transients of overhead transmission lines.

  4. Multiwavelet packet entropy and its application in transmission line fault recognition and classification.

    Science.gov (United States)

    Liu, Zhigang; Han, Zhiwei; Zhang, Yang; Zhang, Qiaoge

    2014-11-01

    Multiwavelets possess better properties than traditional wavelets. Multiwavelet packet transformation has more high-frequency information. Spectral entropy can be applied as an analysis index to the complexity or uncertainty of a signal. This paper tries to define four multiwavelet packet entropies to extract the features of different transmission line faults, and uses a radial basis function (RBF) neural network to recognize and classify 10 fault types of power transmission lines. First, the preprocessing and postprocessing problems of multiwavelets are presented. Shannon entropy and Tsallis entropy are introduced, and their difference is discussed. Second, multiwavelet packet energy entropy, time entropy, Shannon singular entropy, and Tsallis singular entropy are defined as the feature extraction methods of transmission line fault signals. Third, the plan of transmission line fault recognition using multiwavelet packet entropies and an RBF neural network is proposed. Finally, the experimental results show that the plan with the four multiwavelet packet energy entropies defined in this paper achieves better performance in fault recognition. The performance with SA4 (symmetric antisymmetric) multiwavelet packet Tsallis singular entropy is the best among the combinations of different multiwavelet packets and the four multiwavelet packet entropies.

  5. Exact Solutions for a Local Fractional DDE Associated with a Nonlinear Transmission Line

    Science.gov (United States)

    Aslan, İsmail

    2016-09-01

    Of recent increasing interest in the area of fractional calculus and nonlinear dynamics are fractional differential-difference equations. This study is devoted to a local fractional differential-difference equation which is related to a nonlinear electrical transmission line. Explicit traveling wave solutions (kink/antikink solitons, singular, periodic, rational) are obtained via the discrete tanh method coupled with the fractional complex transform.

  6. Study of transmission line attenuation in broad band millimeter wave frequency range

    Energy Technology Data Exchange (ETDEWEB)

    Pandya, Hitesh Kumar B. [ITER-India, IPR, Gandhinagar, Gujarat (India); Austin, M. E. [Institute for Fusion Studies, the University of Texas at Austin, Austin, Texas (United States); Ellis, R. F. [Laboratory for Plasma and Fusion Energy Studies, University of Maryland, College Park, Maryland 20742 (United States)

    2013-10-15

    Broad band millimeter wave transmission lines are used in fusion plasma diagnostics such as electron cyclotron emission (ECE), electron cyclotron absorption, reflectometry and interferometry systems. In particular, the ECE diagnostic for ITER will require efficient transmission over an ultra wide band, 100 to 1000 GHz. A circular corrugated waveguide transmission line is a prospective candidate to transmit such wide band with low attenuation. To evaluate this system, experiments of transmission line attenuation were performed and compared with theoretical loss calculations. A millimeter wave Michelson interferometer and a liquid nitrogen black body source are used to perform all the experiments. Atmospheric water vapor lines and continuum absorption within this band are reported. Ohmic attenuation in corrugated waveguide is very low; however, there is Bragg scattering and higher order mode conversion that can cause significant attenuation in this transmission line. The attenuation due to miter bends, gaps, joints, and curvature are estimated. The measured attenuation of 15 m length with seven miter bends and eighteen joints is 1 dB at low frequency (300 GHz) and 10 dB at high frequency (900 GHz), respectively.

  7. Modern Travelling Wave Based Fault Location Techniques for HVDC Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    CHEN Ping; XU Bingyin; LI Jing; GE Yaozhong

    2008-01-01

    The modern travelling wave based fault location principles for transmission lines are ana-lyzed. In order to apply the travelling wave principles to HVDC transmission lines, the special tech-nical problems are studied. Based on this, a fault locating system for HVDC transmission lines is developed. The system can support modern double ended and single ended travelling wave princi-ples simultaneously, and it is composed of three different parts: travelling wave data acquisition and processing system, communication network and PC based master station. In the system, the fault generated transients are induced from the ground leads of the over-voltage suppression ca-pacitors of an HVDC line through specially developed travelling wave couplers.The system was applied to 500 Kv Gezhouba-Nanqiao(Shanghai)HVDC transmission line in China. Some field op- eration experiences are summarized, showing that the system has very high reliability and accu- racy,and the maximum location error is about 3 km(not more than 0.3% of the total line length). Obviously, the application of the system is successful, and the fault location problem has finally been solved completely since the line operation.

  8. Fault Detection and Localization in Transmission Lines with a Static Synchronous Series Compensator

    Directory of Open Access Journals (Sweden)

    REYES-ARCHUNDIA, E.

    2015-08-01

    Full Text Available This paper proposes a fault detection and localization method for power transmission lines with a Static Synchronous Series Compensator (SSSC. The algorithm is based on applying a modal transformation to the current and voltage signals sampled at high frequencies. Then, the wavelet transform is used for calculating the current and voltage traveling waves, avoiding low frequency interference generated by the system and the SSSC. Finally, by using reflectometry principles, straightforward expressions for fault detection and localization in the transmission line are derived. The algorithm performance was tested considering several study cases, where some relevant parameters such as voltage compensation level, fault resistance and fault inception angle are varied. The results indicate that the algorithm can be successfully be used for fault detection and localization in transmission lines compensated with a SSSC. The estimated error in calculating the distance to the fault is smaller than 1% of the transmission line length. The test system is simulated in PSCAD platform and the algorithm is implemented in MATLAB software.

  9. Transient Stability of the Power System with the Exact Long Transmission Line Model

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2012-01-01

    Full Text Available Problem statement: The exact long transmission line model consists of the lump of the series resistance, reactance and shunt capacitance. With the consideration the actual long transmission line model, it causes in the difficulty of deriving the mathematical model. Approach: This study investigates the transient stability of power system with consideration the exact long transmission line model. The concept of two-port network is applied in this study. The generator, transformer and short transmission line are represented by two-port networks. With the combination principles of the series and shunt connection, the mathematical model is achieved in a much simpler way. The proposed method is tested on the sample system and compared on various cases. Results: The first swing of rotor angle curve of the faulted system without the resistance is obviously higher than that of with the resistance whereas the second swing of the faulted system without the resistance is slightly less than that of with the resistance. The critical clearing time of the system with the resistance is better than that of with resistance. Conclusion: It was found from the simulation results that the resistance of the line provides the improvement of the first swing but not for the second swing. It was found from this study that for practical long line, the resistance is very import parameters to determine the critical clearing time of the single machine infinite system whereas shunt capacitance insignificantly affects on the critical clearing time of the single machine infinite bus system.

  10. Design of the ITER Electron Cyclotron Heating and Current Drive Waveguide Transmission Line

    Science.gov (United States)

    Bigelow, T. S.; Rasmussen, D. A.; Shapiro, M. A.; Sirigiri, J. R.; Temkin, R. J.; Grunloh, H.; Koliner, J.

    2007-11-01

    The ITER ECH transmission line system is designed to deliver the power, from twenty-four 1 MW 170 GHz gyrotrons and three 1 MW 127.5 GHz gyrotrons, to the equatorial and upper launchers. The performance requirements, initial design of components and layout between the gyrotrons and the launchers is underway. Similar 63.5 mm ID corrugated waveguide systems have been built and installed on several fusion experiments; however, none have operated at the high frequency and long-pulse required for ITER. Prototype components are being tested at low power to estimate ohmic and mode conversion losses. In order to develop and qualify the ITER components prior to procurement of the full set of 24 transmission lines, a 170 GHz high power test of a complete prototype transmission line is planned. Testing of the transmission line at 1-2 MW can be performed with a modest power (˜0.5 MW) tube with a low loss (10-20%) resonant ring configuration. A 140 GHz long pulse, 400 kW gyrotron will be used in the initial tests and a 170 GHz gyrotron will be used when it becomes available. Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U.S. Dept. of Energy under contract DE-AC05-00OR22725.

  11. Transmission line component testing for the ITER Ion Cyclotron Heating and Current Drive System

    Science.gov (United States)

    Goulding, Richard; Bell, G. L.; Deibele, C. E.; McCarthy, M. P.; Rasmussen, D. A.; Swain, D. W.; Barber, G. C.; Barbier, C. N.; Cambell, I. H.; Moon, R. L.; Pesavento, P. V.; Fredd, E.; Greenough, N.; Kung, C.

    2014-10-01

    High power RF testing is underway to evaluate transmission line components for the ITER Ion Cyclotron Heating and Current Drive System. The transmission line has a characteristic impedance Z0 = 50 Ω and a nominal outer diameter of 305 mm. It is specified to carry up to 6 MW at VSWR = 1.5 for 3600 s pulses, with transient voltages up to 40 kV. The transmission line is actively cooled, with turbulent gas flow (N2) used to transfer heat from the inner to outer conductor, which is water cooled. High voltage and high current testing of components has been performed using resonant lines generating steady state voltages of 35 kV and transient voltages up to 60 kV. A resonant ring, which has operated with circulating power of 6 MW for 1 hr pulses, is being used to test high power, low VSWR operation. Components tested to date include gas barriers, straight sections of various lengths, and 90 degree elbows. Designs tested include gas barriers fabricated from quartz and aluminum nitride, and transmission lines with quartz and alumina inner conductor supports. The latest results will be presented. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.

  12. Lumped Approximation of a Transmission Line with an Alternative Geometric Discretization

    NARCIS (Netherlands)

    Lopezlena, Ricardo; Scherpen, Jacquelien M.A.

    2004-01-01

    An electromagnetic one-dimensional transmission line represented in a distributed port-Hamiltonian form is lumped into a chain of subsystems which preserve the port-Hamiltonian structure with inputs and outputs in collocated form. The procedure is essentially an adaptation of the procedure for discr

  13. Progress on corrugated waveguide components suitable for ITER ECH&CD transmission lines

    Science.gov (United States)

    Olstad, R. A.; Callis, R. W.; Cengher, M.; Doane, J. L.; Gorelov, Y. A.; Grunloh, H. J.; Moeller, C. P.; Murphy, C. J.

    2012-09-01

    The 2 MW cw requirement for ITER EC transmission lines has led GA to design a number of new and modified components, namely power monitors and polarizers to meet this requirement. In addition, the ITER transmission lines may require sliding joints or bellows to accommodate the thermal expansion of the lines and/or vessel motion. The ex-vessel sections of the EC launchers require double seal waveguides, miter bends and possibly double seal sliding joints to assure tritium retention in this region. GA has developed designs for many of these components and some of them have already been tested at high power at the JAEA RF Test Stand. Thermal analyses of the standard GA power monitor miter bend show that our standard design is suitable for 1 MW cw operation when the H-field is in the plane of the miter bend. For 2 MW cw operation a modified design, which also requires H-plane orientation, has been developed and a prototype has been fabricated and is ready for testing. For long pulse/cw operation, a 2 MW calorimetric miter bend with thermally isolated mirror has been designed and a prototype has been fabricated. Since the mirror is thermally isolated, calorimetry on the mirror cooling water can provide a measure of absorbed power. Such a miter bend, when made in a double seal version, could be useful for monitoring total power at the end of an EC transmission line just before the in-vessel section of an EC launcher. A mode analyzer using an all metal water-cooled beam splitter is being developed for use in measuring in real time the HE11 and higher order mode content or total power in EC transmission lines. Such a high power diagnostic can be very useful in optimizing the alignment of the MOU output into a transmission line and in monitoring the HE11 mode purity at various locations in a transmission line. Prior to making a 63.5 mm 170 GHz version suitable for use on ITER, several prototype 31.75 mm 110 GHz versions have been fabricated and tested at DIII-D. A 170 GHz

  14. Progress on corrugated waveguide components suitable for ITER ECH&CD transmission lines

    Directory of Open Access Journals (Sweden)

    Murphy C.J.

    2012-09-01

    Full Text Available The 2 MW cw requirement for ITER EC transmission lines has led GA to design a number of new and modified components, namely power monitors and polarizers to meet this requirement. In addition, the ITER transmission lines may require sliding joints or bellows to accommodate the thermal expansion of the lines and/or vessel motion. The ex-vessel sections of the EC launchers require double seal waveguides, miter bends and possibly double seal sliding joints to assure tritium retention in this region. GA has developed designs for many of these components and some of them have already been tested at high power at the JAEA RF Test Stand. Thermal analyses of the standard GA power monitor miter bend show that our standard design is suitable for 1 MW cw operation when the H-field is in the plane of the miter bend. For 2 MW cw operation a modified design, which also requires H-plane orientation, has been developed and a prototype has been fabricated and is ready for testing. For long pulse/cw operation, a 2 MW calorimetric miter bend with thermally isolated mirror has been designed and a prototype has been fabricated. Since the mirror is thermally isolated, calorimetry on the mirror cooling water can provide a measure of absorbed power. Such a miter bend, when made in a double seal version, could be useful for monitoring total power at the end of an EC transmission line just before the in-vessel section of an EC launcher. A mode analyzer using an all metal water-cooled beam splitter is being developed for use in measuring in real time the HE11 and higher order mode content or total power in EC transmission lines. Such a high power diagnostic can be very useful in optimizing the alignment of the MOU output into a transmission line and in monitoring the HE11 mode purity at various locations in a transmission line. Prior to making a 63.5 mm 170 GHz version suitable for use on ITER, several prototype 31.75 mm 110 GHz versions have been fabricated and tested at

  15. 76 FR 19744 - Final Tropic to Hatch 138 kV Transmission Line Project Environmental Impact Statement and...

    Science.gov (United States)

    2011-04-08

    ... Forest Service Final Tropic to Hatch 138 kV Transmission Line Project Environmental Impact Statement and Proposed Grand Staircase-Escalante National Monument Management Plan Amendment AGENCY: Forest Service, USDA... Forest, USDA Forest Service, Tropic to Hatch 138kV Transmission Line Project EIS Project Leader, 1789...

  16. Coupling mid-infrared light from a photonic crystal waveguide to metallic transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Blanco-Redondo, Andrea, E-mail: andrea.blanco@tecnalia.com, E-mail: r.hillenbrand@nanogune.eu [ICT-European Software Institute Division, Tecnalia, Ibaizabal Bidea, Ed. 202, 48170 Zamudio, Bizkaia (Spain); Dpto. Electronica y Telecom., E.T.S. Ingeniería Bilbao, UPV/EHU, Alda. Urquijo, 48103 Bilbao, Bizkaia (Spain); Sarriugarte, Paulo [Nanooptics Group, CIC nanoGUNE Consolider, 20018 Donostia–San Sebastian, Gipuzkoa (Spain); Garcia-Adeva, Angel [Dpto. Fisica Aplicada I, E.T.S. Ingeniería de Bilbao, UPV-EHU, Alda. Urquijo, 48103 Bilbao, Bizkaia (Spain); Zubia, Joseba [Dpto. Electronica y Telecom., E.T.S. Ingeniería Bilbao, UPV/EHU, Alda. Urquijo, 48103 Bilbao, Bizkaia (Spain); Hillenbrand, Rainer, E-mail: andrea.blanco@tecnalia.com, E-mail: r.hillenbrand@nanogune.eu [Nanooptics Group, CIC nanoGUNE Consolider, 20018 Donostia–San Sebastian, Gipuzkoa (Spain); IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Bizkaia (Spain)

    2014-01-06

    We propose and theoretically study a hybrid structure consisting of a photonic crystal waveguide (PhC-wg) and a two-wire metallic transmission line (TL), engineered for efficient transfer of mid-infrared (mid-IR) light between them. An efficiency of 32% is obtained for the coupling from the transverse magnetic (TM) photonic mode to the symmetric mode of the TL, with a predicted intensity enhancement factor of 53 at the transmission line surface. The strong coupling is explained by the small phase velocity mismatch and sufficient spatial overlapping between the modes. This hybrid structure could find applications in highly integrated mid-IR photonic-plasmonic devices for biological and gas sensing, among others.

  17. Overlap amplitude and localization properties in aperiodic diluted and non-diluted direct electric transmission lines

    Science.gov (United States)

    Lazo, E.; Castro, C. E.; Cortés-Cortés, F.

    2016-09-01

    In this work we study the relationship existing between the localization properties of the diluted and non-diluted direct electrical transmission lines with the overlap amplitude Cijω = 2 | Iiω Ijω | , where Ijω is the amplitude of the electric current function at jth cell of the transmission line for the state with frequency ω. We distribute two values of inductances LA and LB, according to the generalized aperiodic Thue-Morse m-tupling sequence. We find that the behavior of Ci,jω is directly related to the localization properties of the aperiodic sequences measured by the ξ normalized participation number, the Rq Rényi entropies and the μq moments. In addition, we generalize the scaling relationship for the overlap amplitude Ci,jω, i.e., =(2/N) 2 q.

  18. Comparative analysis of techniques for control of switching overvoltages during transmission lines energization

    Energy Technology Data Exchange (ETDEWEB)

    Mestas, P.; Tavares, M.C. [School of Electrical and Computing Engineering, University of Campinas, PO Box: 6101, 13083-970 Campinas, SP (Brazil)

    2010-01-15

    The energization of long transmission lines can cause high overvoltage stresses not only along the transmission line, but also in the rest of the network. The traditional method of limiting switching overvoltages to acceptable levels is the use of circuit breakers equipped with pre-insertion resistors. The present paper describes a study comparing this traditional method with two other alternatives for the limitation of switching overvoltages during line energization in an actual 500 kV transmission system: the use of metal oxide surge arresters at both line closing of circuit breaker poles. Digital simulations were made with PSCAD/EMTDC software and the degree of shunt compensation is considered as an independent parameter. (author)

  19. Research of Bipolar HVDC Transmission Lines Based on Traveling Wave Differential Protection

    Directory of Open Access Journals (Sweden)

    Baina He

    2013-07-01

    Full Text Available The principle of the traveling wave based differential protection for bipolar HVDC transmission lines is proposed in the paper. Unlike the traditional current differential protection, the quantity of current is replaced by the quantity of the traveling wave for comparison. The traveling wave at the remote end is transferred to the local end for comparison to the local traveling wave. For the bipolar DC transmission lines, the polar-mode (aerial mode traveling waves are employed to establish the discriminative criterion. The ground-mode traveling waves are utilized for faulty line detector for bipolar operation modes. The entire protection scheme is simulated in PSCAD/EMTDC associated with the standard ±500kV HVDC transmission system. The simulation results show that the new protection has the advantages of higher sensitivity, reliability and security. The fault resistance can be coverd by the traveling wave based differential protection reaches to 500 Ohm.    

  20. Fault Locating in HVDC Transmission Lines Using Generalized Regression Neural Network and Random Forest Algorithm

    Directory of Open Access Journals (Sweden)

    M. Farshad

    2013-09-01

    Full Text Available This paper presents a novel method based on machine learning strategies for fault locating in high voltage direct current (HVDC transmission lines. In the proposed fault-location method, only post-fault voltage signals measured at one terminal are used for feature extraction. In this paper, due to high dimension of input feature vectors, two different estimators including the generalized regression neural network (GRNN and the random forest (RF algorithm are examined to find the relation between the features and the fault location. The results of evaluation using training and test patterns obtained by simulating various fault types in a long overhead transmission line with different fault locations, fault resistance and pre-fault current values have indicated the efficiency and the acceptable accuracy of the proposed approach.

  1. submitter Superconducting transmission lines – Sustainable electric energy transfer with higher public acceptance?

    CERN Document Server

    Thomas, Heiko; Chervyakov, Alexander; Stückrad, Stefan; Salmieri, Delia; Rubbia, Carlo

    2016-01-01

    Despite the extensive research and development investments into superconducting science and technology, both at the fundamental and at the applied levels, many benefits of superconducting transmission lines (SCTL) remain unknown to the public and decision makers at large. This paper aims at informing about the progress in this important research field. Superconducting transmission lines have a tremendous size advantage and lower total electrical losses for high capacity transmission plus a number of technological advantages compared to solutions based on standard conductors. This leads to a minimized environmental impact and enables an overall more sustainable transmission of electric energy. One of the direct benefits may be an increased public acceptance due to the low visual impact with a subsequent reduction of approval time. The access of remote renewable energy (RE) sources with high-capacity transmission is rendered possible with superior efficiency. That not only translates into further reducing $CO_2...

  2. Theoretical Analysis of the Characteristic Impedance in Metal-Insulator-Metal Plasmonic Transmission Lines

    CERN Document Server

    Nejati, Hamid

    2013-01-01

    We propose a closed form formulation for the impedance of the Metal-Insulator-Metal (MIM) plasmonic transmission lines by solving the Maxwell's equations. We provide approximations for thin and thick insulator layers sandwiched between metallic layers. In the case of very thin dielectric layer, the surface waves on both interfaces are strongly coupled resulting in an almost linear dependence of the impedance of the plasmonic transmission line on the thickness of the insulator layer. On the other hand, for very thick insulator layer, the impedance does not vary with the insulator layer thickness due to the weak-coupling/decoupling of the surface waves on each metal-insulator interface. We demonstrate the effectiveness of our proposed formulation using two test scenarios, namely, almost zero reflection in Tee-junction and reflection from line discontinuity in the design of Bragg reflectors, where we compare our formulation against previously published results.

  3. Special Problems in Pilot Protections of Transmission Lines Connecting Wind Farms

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    As the penetration of wind power into power grids increases, higher demands are made on the stability and protection of power systems. Unlike traditional synchronous generators, wind turbines are different on the short-circuit and impedance characteristics, thus some problems exist in pilot protections of transmission lines connecting wind farms. When a single-phase fault occurs on a transmission line, the phase selector based on current-difference sudden-change may mistake the single-phase fault for a phase-to-phase fault. This paper studies the impedance characteristics of an asynchronous wind generator, and analyzes the behavior of a fault phase selector under different conditions. Then, the paper explains that inequality between positive and negative branch coefficients is the cause for the mal-operation of the fault phase selector. Finally, some simulations are done in MATLAB to validate analysis results.

  4. Theoretical limit of repeater spacing in an optical transmission line utilizing Raman amplification

    Science.gov (United States)

    Nakashima, T.; Seikai, S.; Nakazawa, M.; Negishi, Y.

    1986-08-01

    The limit of repeater spacing is investigated theoretically for optical transmission lines utilizing stimulated Raman scattering to amplify the signal light. Achievable repeater spacing is numerically estimated on the basis of coupled power equations and measured fiber characteristics for various signal wavelengths and relative index differences. Three types of transmission line configurations are considered, i.e., utilization of forward only, backward only, and bidirectional amplification. In the third case, a transmission distance of more than 400 km is predicted for an input signal light power of 100 microW, a signal wavelength of 1.57 microns, and a pump power of 0.5 W using a fiber with a relative index difference of 1 percent for signal light amplification.

  5. Transmission line design for a power distribution system at 20 kHz for aircraft

    Science.gov (United States)

    Zelby, L. W.; Mathes, J. B.; Shawver, J. W.

    1986-01-01

    A low inductance, low characteristic impedance transmission line was designed for a 20 kHz power distribution system. Several different conductor configurations were considered: strip lines, interdigitated metal ribbons, and standard insulated wires in multiwire configurations (circular and rectangular cylindrical arrangements). The final design was a rectangular arrangement of multiple wires of the same gauge with alternating polarities from wire to wire. This offered the lowest inductance per unit length (on the order of several nanohenries/meter) and the lowest characteristic impedance (on the order of one Ohm). Standard multipin connectors with gold-plated elements were recommended with this transmission line, the junction boxes to be internally connected with flat metal ribbons for low inductance, and the line to be constructed in sections of suitable length. Computer programs for the calculation of inductance of multiwire lines and of capacitances of strip lines were developed.

  6. Synchrophasors-Assisted IPII-Based Intelligent Relaying for Transmission Lines Including UPFC

    Science.gov (United States)

    Jena, Manas Kumar; Samantaray, S. R.

    2015-02-01

    This paper proposes a synchrophasors-assisted intelligent relaying scheme for transmission lines compensated by Unified Power Flow Controller (UPFC). The algorithm uses a new relaying signal termed as imaginary part of integrated impedance (IPII). The synchronized phasor measurements at both ends of the transmission line are used to extract voltage and current phasors from instantaneous voltage and current signals. The voltage and current phasors are utilized to derive IPII of each phase. Further, IPII of each phase is used as input to a data-mining model termed as decision tree (DT) which provides the final relaying decision. The proposed algorithm is validated on real-time digital simulator (RTDS) platform, and the results obtained indicate that the proposed scheme is both dependable and secure in protecting transmission system compensated by UPFC.

  7. Modulational Instability in a Pair of Non-identical Coupled Nonlinear Electrical Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    Eric Tala-Tebue; Aurelien Kenfack-Jiotsa; Marius Hervé Tatchou-Ntemfack; Timoléon Crépin Kofané

    2013-01-01

    In this work,we investigate the dynamics of modulated waves non-identical coupled nonlinear transmission lines.Traditional methods for avoiding mode mixing in identical coupled nonlinear electrical lines consist of adding the same number of linear inductors in each branch.Adding linear inductors in a single line leads to asymmetric coupled nonlinear electrical transmission lines which propagate the signal and the mode mixing.On one hand,the difference between the two lines induced the fission for only one mode of propagation.This fission is influenced by the amplitude of the signal and the amount of the input energy as well; it also narrows the width of the input pulse soliton,leading to a possible increasing of the bit rate.On the other hand,the dissymmetry of the two lines converts the network into a good amplifier for the w_ mode which corresponds to the regime admitting low frequencies.

  8. Advances in fibers and transmission line technology for long haul submarine systems

    Science.gov (United States)

    Peckham, David W.; Kim, Jinkee; Sun, Yi; Lingle, Robert L., Jr.; Levring, Ole

    2007-11-01

    The 7.1-magnitude earthquake on December 26, 2006 in the Strait of Luzon resulted in the failure of several submarine cable systems. Seven of the nine cables that pass through the strait were damaged, disrupting communications to China, Taiwan, Japan, Korea and Singapore. This recent event highlighted the dependence of international communications on submarine fiber optic transmission systems. This paper will review the evolution of optical fiber transmission line technology that has been deployed in the long haul undersea telecommunications network. It will start with a discussion of the chronological evolution of the optical fiber transmission line architecture in section one, then give more detail regarding the technology that is still being deployed today.

  9. Effects of Un-transposed UHV Transmission Line on Fault Analysis of Power Systems

    Institute of Scientific and Technical Information of China (English)

    WANG Anning; CHEN Qing; ZHOU Zhanping

    2008-01-01

    The conventional fault analysis method based on symmetrical components supposes that the three-phase parameters of un-transposed transmission line are symmetrical in case of fault. The errors caused by the method with the symmetrical distributed parameter circuit model as the equivalent circuit of the un-transposed ultra high voltage (UHV) transmission line were studied under both normal operation and fault, and the corresponding problems arising were pointed out. By contrast with electromagnetic transient and power electronics (EMTPE) simulation results with the asymmetrical distributed parameter circuit model of un-transposed line, it is shown that the conventional method cannot show the existence of negative and zero sequences before fault happening and there are many errors on voltage and current after fault happening which are different with fault types. The error ranges of voltage and current are 2.13%-81.13% and -7.82%-86.15%, respectively.

  10. Modeling Delays of Microwave Transistors and Transmission Lines by the 2nd Order Bessel Function

    Directory of Open Access Journals (Sweden)

    K. Ulovec

    2007-04-01

    Full Text Available At present, most of simulation programs can characterize gate delays of microwave transistors. However, the delay is mostly approximated by means of first-order differential equations. In the paper, a more accurate way is suggested which is based on an appropriate second-order differential equation. Concerning the transmission line delay, majority of the simulation programs use both Branin (for lossless lines and LCRG (for lossy lines models. However, the first causes extreme simulation times, and the second causes well-known spurious oscillations in the simulation results. In the paper, an unusual way for modeling the transmission line delay is defined, which is also based on the second-order Bessel function. The proposed model does not create the spurious oscillations and the simulation times are comparable with those obtained with the classical models. Properties of the implementation of the second-order Bessel function are demonstrated by analyses of both digital and analog microwave circuits.

  11. Reduction of radiation loss at small-radius bend using spoof surface plasmon polariton transmission line.

    Science.gov (United States)

    Tang, Wen Xuan; Zhang, Hao Chi; Liu, Jun Feng; Xu, Jie; Cui, Tie Jun

    2017-01-23

    Spoof surface plasmon polariton (SPP) has been realized at low frequencies through corrugated metallic structures. As two-dimensional application, the ultrathin SPP transmission lines (TLs) have been proposed with great potentials for microwave compact circuits due to the strong field confinement and enhancement, as well as controllable dispersive properties. In this paper, we examine the radiation loss at small-radius bend, which may cause severe crosstalk in highly-integrated circuits or systems, for the SPP TLs. We theoretically analyze that the SPP TL has essential merit of low radiation loss, and show better performance of SPP TL than the conventional microstrip line through numerical simulations and experiments. Both simulated and measured results demonstrate that the new type of transmission line can efficiently suppress the radiation loss at small-radius bend, and hence reduce the crosstalk in circuits and systems.

  12. Accurate one-end fault location for overhead transmission lines in interconnected power systems

    Energy Technology Data Exchange (ETDEWEB)

    Eisa, Amir A.A.; Ramar, K. [Faculty of Engineering, Multimedia University, 63100 Cyberjaya (Malaysia)

    2010-06-15

    This paper presents a new one-end fault location method for overhead transmission lines embedded in a general n-bus interconnected power system. High accuracy in fault location is achieved by using both an accurate distributed parameters model for the faulted transmission line, and a two-bus Thevenin equivalent network model for the power system that accurately accounts for its interconnectivity. The method has been tested using transient fault data obtained from PSCAD/EMTDC simulations of an 11-bus interconnected power system. The results obtained indicate that the method is capable of estimating the fault distance with high accuracy for various fault conditions. They also indicate that method is sensitive to errors in the value of the local bus impedance, but is insensitive to errors in the value of the remote bus impedance. (author)

  13. Rolled-up transmission line structure for a radiofrequency integrated circuit (RFIC)

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiuling; Huang, Wen

    2015-04-28

    A rolled-up transmission line structure for a radiofrequency integrated circuit (RFIC) comprises a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis, where the multilayer sheet comprises a conductive pattern layer on a strain-relieved layer. The conductive pattern layer comprises a first conductive film and a second conductive film separated from the first conductive film in a rolling direction. In the rolled configuration, the first conductive film surrounds the longitudinal axis, and the second conductive film surrounds the first conductive film. The first conductive film serves as a signal line and the second conductive film serves as a conductive shield for the rolled-up transmission line structure.

  14. High power testing of water-cooled waveguide for ITER-like ECH transmission lines

    Science.gov (United States)

    Anderson, J. P.; Doane, J. L.; Grunloh, H. J.; O'Neill, R. C.; Ikeda, R.; Oda, Y.; Takahashi, K.; Sakamoto, K.

    2017-05-01

    The results of high power testing of new water-cooled ECH waveguide components for ITER are presented. The components are a precision-coupled 4.2 m waveguide assembly, a short expansion joint, and water-cooled waveguide for gyrotron commissioning. The testing was conducted at the QST Naka Fusion Institute using gyrotron pulses of 450 kW at 170 GHz for 300 s. Analysis shows that the power absorbed per unit length for the various waveguide components are dependent on location in the transmission line with respect to high order mode generators, such as miter bends. Additionally, larger-than-expected reflections from the load led to high absorption levels in the transmission line.

  15. Optical and electrical enhancement of the propagation time in superconducting transmission lines

    CERN Document Server

    Cho, S H

    2000-01-01

    optical pulse energy and current controlled delays in the propagation time of electrical picosecond pulses in YBa sub 2 Cu sub 3 O sub 7 sub - sub x (YBCO) superconducting transmission lines have been investigated by using picosecond optoelectronic techniques. Electrical pulses, generated using silicon-on-sapphire photoconductive switches driven by a mode-locked Nd:YAG pumped dye laser, are propagated on superconducting transmission lines. The lines are patterned in the geometry of a microstrip and illuminated by the frequency-doubled output of an Nd:YAG laser. The measured propagation time shows a squared dependence on the optical pulse energy. For the applied current dependence, the delay through the line is tuned by 16 psec by varying the bias from zero to 190 mA. The results are in good agreement with the Ginzburg-Landau theory for the case of a uniform current density through a thin film.

  16. A Novel Fault Location Algorithm for Double-Circuit Transmission Lines based on Distributed Parameter

    Institute of Scientific and Technical Information of China (English)

    商立群; 施围

    2006-01-01

    A new fault location algorithm for double-circuit transmission lines is described in this paper. The proposed method uses data extracted from two ends of the transmission lines and thus eliminates the effects of the source impedance and the fault resistance. The distributed parameter model and the modal transformation are also employed. Depending on modal transformation, the coupled equations of the lines are converted into decoupled ones. In this way, the mutual coupling effects between adjacent circuits of the lines are eliminated and therefore an accurate fault location can be achieved. The proposed method is tested via digital simulation using EMTP in conjunction with MATLAB. The test results corroborate the high accuracy of the proposed method.

  17. Rényi entropies of electrical transmission lines with Fibonacci distribution of inductances

    Energy Technology Data Exchange (ETDEWEB)

    Lazo, E., E-mail: elazo@uta.cl [Departamento de Física, Facultad de Ciencias, Universidad de Tarapacá, Arica (Chile); Mellado, F. [Departamento de Física, Facultad de Ciencias, Universidad de Tarapacá, Arica (Chile); Escuela Universitaria de Ingeniería Eléctrica-Electrónica, Universidad de Tarapacá, Arica (Chile); Saavedra, E. [Departamento de Física, Facultad de Ciencias, Universidad de Tarapacá, Arica (Chile)

    2012-10-01

    We study classical dual transmission lines with constant capacitances C{sub j}=C{sub 0}, ∀j, when we distribute two inductance values L{sub A} and L{sub B} according to the Fibonacci sequence. Using the electric current function I{sub j}(ω), we study the normalized localization length Λ(ω), the Rényi entropies R{sub m}(ω) and the normalized information length β(ω). We found three kinds of behavior of the I{sub j}(ω) function: localized, extended and intermediate. In addition, it is found that the transmission line with Fibonacci distribution of inductances shows a behavior characteristic of quasi-periodic systems, namely, a self-similar frequency spectrum, where each subband is divided into three subbands, but the number of global subbands is greater than four.

  18. One modified method of characteristics used to analyze the multiconductor transmission lines

    Institute of Scientific and Technical Information of China (English)

    Fu Jiwei; Hou Chaozhen; Dou Lihua

    2006-01-01

    To solve the coupling effect of multiconductor transmission lines excited by external electromagnetic wave, the modified method of characteristics is proposed. The modified method of characteristics which can compute the terminal induced voltages excited by the external electromagnetic wave when the terminal networks or interconnection networks contain the dynamic elements is introduced. The simulation results indicate that the modified method can analyze the terminal induced voltages when the terminal networks or the interconnection networks contain the dynamic elements excited by the external electromagnetic wave. And the results are compared with the results acquired by FDTD method, the two results are completely same. So one effective modified method is implemented to compute the transmission lines.

  19. Minimal inductance for axisymmetric transmission lines with radially dependent anode-cathode gap

    Directory of Open Access Journals (Sweden)

    Eduardo M. Waisman

    2009-09-01

    Full Text Available We extend the variational calculus technique for inductance minimization of constant gap axisymmetric transmission lines (TL, introduced by Hurricane [J. Appl. Phys. 95, 4503 (2004JAPIAU0021-897910.1063/1.1687986], to the case in which the anode-cathode gap is a linear function of the midgap radius. The full analytic optimal midgap solution curve z(r yielding minimum inductance is obtained in terms of a single parameter ρ_{0}, determined numerically by imposing that z(r goes through prescribed end points. The radius of curvature ρ(r of the optimal curve is obtained everywhere the function is defined, even outside of the end point range, and it is shown that a convenient choice is ρ_{0}=ρ(0. The value of the transmission line inductance is calculated by 1D numerical quadrature. A simple numerical technique is introduced for TL with nonlinear radial gap dependence.

  20. Reduction of radiation loss at small-radius bend using spoof surface plasmon polariton transmission line

    Science.gov (United States)

    Tang, Wen Xuan; Zhang, Hao Chi; Liu, Jun Feng; Xu, Jie; Cui, Tie Jun

    2017-01-01

    Spoof surface plasmon polariton (SPP) has been realized at low frequencies through corrugated metallic structures. As two-dimensional application, the ultrathin SPP transmission lines (TLs) have been proposed with great potentials for microwave compact circuits due to the strong field confinement and enhancement, as well as controllable dispersive properties. In this paper, we examine the radiation loss at small-radius bend, which may cause severe crosstalk in highly-integrated circuits or systems, for the SPP TLs. We theoretically analyze that the SPP TL has essential merit of low radiation loss, and show better performance of SPP TL than the conventional microstrip line through numerical simulations and experiments. Both simulated and measured results demonstrate that the new type of transmission line can efficiently suppress the radiation loss at small-radius bend, and hence reduce the crosstalk in circuits and systems. PMID:28112238

  1. Transmission line inversion and synthesis from the point of view of transient response

    Science.gov (United States)

    Sondhi, M. M.

    1972-01-01

    The transmission line inversion problem is applied to the speech communication process. The problem involves acquiring information necessary for synthesis of speech and for making models of the speech production mechanism. Formulation for the problem is derived from an analysis of the human vocal tract functions. It is known that speech sounds are produced by acoustic excitation of the tract by means of quasi-periodic pulses from the vocal cords during vowel sounds and turbulent air flow at various points along the tract during fricative sounds. By assuming plane wave propagation, differential equations are obtained relating the cross sectional area of the tract, the pressure, and the volume velocity. By replacing the pressure factor with a voltage factor and the volume velocity by current, the problem becomes a transmission line problem.

  2. Deflection Determination of Reinforced Concrete Support Poles for Overhead Transmission Lines

    Directory of Open Access Journals (Sweden)

    M. A. Korotkevich

    2011-01-01

    Full Text Available The paper contains values of torque magnification ratio while shifting vertical loads due to horizontal wind forces affecting on supports of overhead transmission lines of 35 kV and higher. These values pertain to various types of unified reinforced concrete conic and cylindrical supports while changing climatic conditions. The values make it possible to exclude rather complicated calculations in respect of support deflection in the case when there is uncertainty in initial data.

  3. A Comparative Parametric Analysis of the Ground Fault Current Distribution on Overhead Transmission Lines

    OpenAIRE

    VINTAN, M.

    2016-01-01

    The ground fault current distribution in an effectively grounded power network is affected by various factors, such as: tower footing impedances, spans lengths, configuration and parameters of overhead ground wires and power conductors, soil resistivity etc. In this paper, we comparatively analyze, using different models, the ground fault current distribution in a single circuit transmission line with one ground wire. A parametric comparative analysis was done in order to stud...

  4. Hydro-Quebec TransEnergie's perspective on overhead transmission line protection against lightning

    Energy Technology Data Exchange (ETDEWEB)

    Dutil, A. [Hydro-Quebec, Montreal, PQ (Canada). TransEnergie Div.

    2006-07-01

    Hydro-Quebec TransEnergie's interest in transmission line surge arresters (TLSA) was discussed. The utility conducted studies regarding the use of TLSAs to reduce outages caused by lightning in overhead transmission lines having voltages of 52 to 330 kV. It was determined that in some cases, TLSA is the only solution to reducing flashover initiated by lightning. This paper presented the results of 4 different TLSA configurations in which the impact of grounding resistance on TLSA performance was examined in an effort to determine the most effective configuration. The study revealed that lightning flashovers could be reduced by 70 per cent by installing 1 TLSA on every 2 poles of a 52 kV transmission line. The TLSA should be mounted on one pole structure and the earth wire on the unprotected poles should be removed. According to several tests conducted at Hydro-Quebec's Institut de Recherche en Electricite du Quebec (IREQ), the energy absorption capability of arresters from 4 different manufacturers proved to be at least 6 kJ/kv. The arresters failure rate was estimated to 3 per cent every time a lightning strike occurred on a transmission line. It was suggested that a 100 km long line with one pole every 60 meters should not have more than one arrester failure per year. The arresters must be installed with a mechanical device that could disconnect a failed unit from the transmission system to avoid a permanent fault on the network. It was concluded that TLSAs are useful in reducing lightning flashovers caused by lightning. However, Hydro-Quebec TransEnergie still has concerns regarding their cost, reliability, impact on line maintenance, testing difficulties in the field, mechanical stress on the conductors, and their ability to withstand dielectric behaviour under ice. tabs., figs.

  5. Marys Lake 69/115-kV transmission line upgrade and substation expansion projects

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    Western Area Power Administration (Western) and the Platte River Power Authority (Platte River) propose to upgrade portions of the existing electric transmission and substation system that serves the Town of Estes Park, Colorado. The existing transmission lines between the Estes Power Plant Switchyard and the Marys Lake Substation include a 115,000 volt (115-kV) line and 69,000 volt (69-kV) line. Approximately one mile is a double-circuit 115/69-kV line on steel lattice structures, and approximately two miles consists of separate single-circuit 115-kV and a 69-kV lines, constructed on wood H-Frame structures. Both lines were constructed in 1951 by the US Bureau of Reclamation. The existing transmission lines are on rights-of-way (ROW) that vary from 75 feet to 120 feet and are owned by Western. There are 48 landowners adjacent to the existing ROW. All of the houses were built adjacent to the existing ROW after the transmission lines were constructed. Upgrading the existing 69-kV transmission line between the Marys Lake Substation and the Estes Power Plant Switchyard to 115-kV and expanding the Marys Lake Substation was identified as the most effective way in which to improve electric service to Estes Park. The primary purpose and need of the proposed project is to improve the reliability of electric service to the Town of Estes Park. Lack of reliability has been a historical concern, and reliability will always be less than desired until physical improvements are made to the electrical facilities serving Estes Park.

  6. Determing the Time Dependence of Electrical Gradients in Railguns using the Transmission Line

    Science.gov (United States)

    2008-09-01

    Phys., 40, 274-283. Feynman , R., Leighton, R., and Sands, M. 1964: The Feynman Lectures in Physics vol II, 3rd ed. Addison Wesley, 238 pp...2) This is similar to the familiar transmission line equation ( Feynman , et al, 1964) relating the gradient of the voltage along a transmission...strong function of time (skin effect) while LX is relatively insensitive to time. We attribute this to fundamental differences in the physics of the

  7. Adaptive Neurofuzzy Inference System-Based Pollution Severity Prediction of Polymeric Insulators in Power Transmission Lines

    OpenAIRE

    C. Muniraj; Chandrasekar, S

    2011-01-01

    This paper presents the prediction of pollution severity of the polymeric insulators used in power transmission lines using adaptive neurofuzzy inference system (ANFIS) model. In this work, laboratory-based pollution performance tests were carried out on 11 kV silicone rubber polymeric insulator under AC voltage at different pollution levels with sodium chloride as a contaminant. Leakage current was measured during the laboratory tests. Time domain and frequency domain characteristics of leak...

  8. Electrostatic force on the rectangular shield wall of a strip transmission line

    Institute of Scientific and Technical Information of China (English)

    向裕民

    2002-01-01

    For a strip transmission line shielded by rectangular walls,the Green's function is helpful to construct the variation expression of the electrostatic energy.Thomson theorem is employed to determine the charge distribution on the strip.The electrostatic force on each side of the rectangular shield wall is achieved by using the principle of virtual work.The results is easy to be obtained by computerized calculation.

  9. Critical parameters affecting the design of high frequency transmission lines in standard CMOS technology

    KAUST Repository

    Al-Attar, Talal

    2017-05-13

    Different structures of transmission lines were designed and fabricated in standard CMOS technology to estimate some critical parameters including the RMS value of the surface roughness and the loss tangent. The input impedances for frequencies up to 50 GHz were modeled and compared with measurements. The results demonstrated a strong correlation between the used model with the proposed coefficients and the measured results, attesting the robustness of the model and the reliability of the incorporated coefficients values.

  10. Electrical and mechanical design criteria for EHV and UHV: overhead transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    The results are presented of a program devoted to the selection of electrical and mechanical design criteria and parameters for overhead power transmission lines for ac systems rated at from 345 to 1100 kV and for dc systems rated at from 600 to 1200 kV. Information is included on the environmental effects, i.e., audible noise and electric fields, of the lines, mechanical and economic requirements, safety, failures, grounding, and lightning protection. (LCL)

  11. Thermal fluctuations in resonant motion of fluxons on a Josephson transmission line: Theory and experiment

    DEFF Research Database (Denmark)

    Jørgensen, E.; Koshelets, V. P.; Monaco, Roberto

    1982-01-01

    The radiation emission from long and narrow Josephson tunnel junctions dc-current biased on zero-field steps has been ascribed to resonant motion of fluxons on the transmission line. Within this dynamic model a theoretical expression for the radiation linewidth is derived from a full statistical ...... treatment of thermal fluctuations in the fluxon velocity. The result appears to be very general and is corroborated by experimental determination of linewidth and frequency of radiation emitted from overlap Nb-I-Pb junctions....

  12. The Effect of R/X Ratio of the Short Transmission Line on Transient Stability

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2012-01-01

    Full Text Available Problem statement: The exact short transmission line model consists of the resistance and reactance. Most of previous researches study the transient stability of single machine infinite bus with neglecting the resistance of the line. Thus the simulation results may not close to the practical system. With the consideration with the actual short line model, it causes difficulty of deriving the mathematical model. Approach: This study investigates the transient stability of power system with consideration of the exact short transmission line model. The concept of two-port network is applied in this study. The generator, transformer and short transmission line are represented by a two-port. With the combination principles of the series and shunt connection, the mathematical model is achieved in a much simpler way. The proposed method is tested on the sample system and compared on various cases. Results: The first swing of rotor angle curve of the faulted system without the resistance is obviously higher than that of with the resistance whereas the second swing of the faulted system, without the resistance, is slightly less than that of with the resistance. The critical clearing time of the system with the resistance is better than that of with resistance. Conclusion: It was found in this study that the resistance of the transmission line should be included for investigating the transient stability of the power system. The resistance of the line provides the better results of the critical clearing time of the system but it provides the negative effect on damping improvement.

  13. Improved Fault Classification in Series Compensated Transmission Line: Comparative Evaluation of Chebyshev Neural Network Training Algorithms.

    Science.gov (United States)

    Vyas, Bhargav Y; Das, Biswarup; Maheshwari, Rudra Prakash

    2016-08-01

    This paper presents the Chebyshev neural network (ChNN) as an improved artificial intelligence technique for power system protection studies and examines the performances of two ChNN learning algorithms for fault classification of series compensated transmission line. The training algorithms are least-square Levenberg-Marquardt (LSLM) and recursive least-square algorithm with forgetting factor (RLSFF). The performances of these algorithms are assessed based on their generalization capability in relating the fault current parameters with an event of fault in the transmission line. The proposed algorithm is fast in response as it utilizes postfault samples of three phase currents measured at the relaying end corresponding to half-cycle duration only. After being trained with only a small part of the generated fault data, the algorithms have been tested over a large number of fault cases with wide variation of system and fault parameters. Based on the studies carried out in this paper, it has been found that although the RLSFF algorithm is faster for training the ChNN in the fault classification application for series compensated transmission lines, the LSLM algorithm has the best accuracy in testing. The results prove that the proposed ChNN-based method is accurate, fast, easy to design, and immune to the level of compensations. Thus, it is suitable for digital relaying applications.

  14. Lightning Protection Performance Assessment of Transmission Line Based on ATP model Automatic Generation

    Directory of Open Access Journals (Sweden)

    Luo Hanwu

    2016-01-01

    Full Text Available This paper presents a novel method to solve the initial lightning breakdown current by combing ATP and MATLAB simulation software effectively, with the aims to evaluate the lightning protection performance of transmission line. Firstly, the executable ATP simulation model is generated automatically according to the required information such as power source parameters, tower parameters, overhead line parameters, grounding resistance and lightning current parameters, etc. through an interface program coded by MATLAB. Then, the data are extracted from the generated LIS files which can be obtained by executing the ATP simulation model, the occurrence of transmission lie breakdown can be determined by the relative data in LIS file. The lightning current amplitude should be reduced when the breakdown occurs, and vice the verse. Thus the initial lightning breakdown current of a transmission line with given parameters can be determined accurately by continuously changing the lightning current amplitude, which is realized by a loop computing algorithm that is coded by MATLAB software. The method proposed in this paper can generate the ATP simulation program automatically, and facilitates the lightning protection performance assessment of transmission line.

  15. Assessment of surge arrester failure rate and application studies in Hellenic high voltage transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Christodoulou, C.A.; Fotis, G.P.; Gonos, I.F.; Stathopulos, I.A. [National Technical University of Athens, School of Electrical and Computer Engineering, High Voltage Laboratory, 9 Iroon Politechniou St., Zografou Campus, 157 80 Athens (Greece); Ekonomou, L. [A.S.PE.T.E. - School of Pedagogical and Technological Education, Department of Electrical Engineering Educators, N. Heraklion, 141 21 Athens (Greece)

    2010-02-15

    The use of transmission line surge arresters to improve the lightning performance of transmission lines is becoming more common. Especially in areas with high soil resistivity and ground flash density, surge arresters constitute the most effective protection mean. In this paper a methodology for assessing the surge arrester failure rate based on the electrogeometrical model is presented. Critical currents that exceed arresters rated energy stress were estimated by the use of a simulation tool. The methodology is applied on operating Hellenic transmission lines of 150 kV. Several case studies are analyzed by installing surge arresters on different intervals, in relation to the region's tower footing resistance and the ground flash density. The obtained results are compared with real records of outage rate showing the effectiveness of the surge arresters in the reduction of the recorded failure rate. The presented methodology can be proved valuable to the studies of electric power systems designers intending in a more effective lightning protection, reducing the operational costs and providing continuity of service. (author)

  16. A Pilot Directional Protection for HVDC Transmission Line Based on Relative Entropy of Wavelet Energy

    Directory of Open Access Journals (Sweden)

    Sheng Lin

    2015-07-01

    Full Text Available On the basis of analyzing high-voltage direct current (HVDC transmission system and its fault superimposed circuit, the direction of the fault components of the voltage and the current measured at one end of transmission line is certified to be different for internal faults and external faults. As an estimate of the differences between two signals, relative entropy is an effective parameter for recognizing transient signals in HVDC transmission lines. In this paper, the relative entropy of wavelet energy is applied to distinguish internal fault from external fault. For internal faults, the directions of fault components of voltage and current are opposite at the two ends of the transmission line, indicating a huge difference of wavelet energy relative entropy; for external faults, the directions are identical, indicating a small difference. The simulation results based on PSCAD/EMTDC show that the proposed pilot protection system acts accurately for faults under different conditions, and its performance is not affected by fault type, fault location, fault resistance and noise.

  17. Bias-field controlled phasing and power combination of gyromagnetic nonlinear transmission lines.

    Science.gov (United States)

    Reale, D V; Bragg, J-W B; Gonsalves, N R; Johnson, J M; Neuber, A A; Dickens, J C; Mankowski, J J

    2014-05-01

    Gyromagnetic Nonlinear Transmission Lines (NLTLs) generate microwaves through the damped gyromagnetic precession of the magnetic moments in ferrimagnetic material, and are thus utilized as compact, solid-state, frequency agile, high power microwave (HPM) sources. The output frequency of a NLTL can be adjusted by control of the externally applied bias field and incident voltage pulse without physical alteration to the structure of the device. This property provides a frequency tuning capability not seen in many conventional e-beam based HPM sources. The NLTLs developed and tested are mesoband sources capable of generating MW power levels in the L, S, and C bands of the microwave spectrum. For an individual NLTL the output power at a given frequency is determined by several factors including the intrinsic properties of the ferrimagnetic material and the transmission line structure. Hence, if higher power levels are to be achieved, it is necessary to combine the outputs of multiple NLTLs. This can be accomplished in free space using antennas or in a transmission line via a power combiner. Using a bias-field controlled delay, a transient, high voltage, coaxial, three port, power combiner was designed and tested. Experimental results are compared with the results of a transient COMSOL simulation to evaluate combiner performance.

  18. Multivariable time series prediction for the icing process on overhead power transmission line.

    Science.gov (United States)

    Li, Peng; Zhao, Na; Zhou, Donghua; Cao, Min; Li, Jingjie; Shi, Xinling

    2014-01-01

    The design of monitoring and predictive alarm systems is necessary for successful overhead power transmission line icing. Given the characteristics of complexity, nonlinearity, and fitfulness in the line icing process, a model based on a multivariable time series is presented here to predict the icing load of a transmission line. In this model, the time effects of micrometeorology parameters for the icing process have been analyzed. The phase-space reconstruction theory and machine learning method were then applied to establish the prediction model, which fully utilized the history of multivariable time series data in local monitoring systems to represent the mapping relationship between icing load and micrometeorology factors. Relevant to the characteristic of fitfulness in line icing, the simulations were carried out during the same icing process or different process to test the model's prediction precision and robustness. According to the simulation results for the Tao-Luo-Xiong Transmission Line, this model demonstrates a good accuracy of prediction in different process, if the prediction length is less than two hours, and would be helpful for power grid departments when deciding to take action in advance to address potential icing disasters.

  19. Study on galloping behavior of iced eight bundle conductor transmission lines

    Science.gov (United States)

    Zhou, Linshu; Yan, Bo; Zhang, Liang; Zhou, Song

    2016-02-01

    Wind tunnel test was carried out to obtain the aerodynamic coefficients of an eight bundle conductor accreted with crescent-shaped ice. A user-defined cable element with torsional degree of freedom is developed in ABAQUS software to capture the torsional deformation of the iced conductors during galloping. By means of the user-defined cable element, different damping ratios in in-plane, out-of-plane and torsional directions of the conductors can be defined and the aerodynamic forces varying with their motion status can be exerted on the conductors conveniently when ABAQUS is used to simulate galloping of transmission lines. A wind tunnel test to model galloping of an iced eight bundle conductor segment was carried out, and the validity of the numerical simulation method is demonstrated by the agreement of the galloping orbit of the bundle conductor segment model recorded in the test and that by the numerical simulation. Furthermore, galloping behavior, including dynamic responses, galloping orbits, frequencies, vibration modes and amplitudes, of typical iced eight bundle conductor transmission lines in the cases of different span lengths, initial tensions in sub-conductors, wind velocities, angles of wind attack and damping ratios is studied, and the galloping behavior of the lines with internal resonance conditions is discussed. The obtained results may provide a fundamental tool for the development of anti-galloping techniques of eight bundle conductor transmission lines.

  20. Design and fabrication of the high-power RF transmission line into the PEFP linac tunnel

    Science.gov (United States)

    Seol, Kyung-Tae; Kwon, Hyeok-Jung; Kim, Han-Sung; Cho, Yong-Sub

    2012-07-01

    The 100-MeV proton linear accelerator (linac) for the Proton Engineering Frontier Project (PEFP) has been developed and will be installed at the Gyeong-ju site. For the linac, a total of 11 sets of RF systems are required, and the waveguide layout was fixed to install high-power RF (HPRF) systems. One of the important interfaces with the building construction is the high-power radio-frequency (HPRF) transmission line embedded in the tunnel, which is used to transmit 1-MW RF power to each cavity in the tunnel. The waveguide section penetrating into the linac tunnel was designed with a bending structure for radiation shielding, and the dependence of its voltage standing-wave ratio (VSWR) on the chamfer length of the bending was calculated. The HPRF transmission line was fabricated into a piece of waveguide to prevent moisture and any foreign debris inside the 2.5-m thick concrete block. Air leakage was checked with a pressure of 0.25 psig of nitrogen gas, and a maximum VSWR of 1.196 was obtained by measuring the vector reflection coefficients with the quarter-wave transmission section. In this paper, the design and the fabrication of the HPRF transmission line into the PEFP linac tunnel are presented.

  1. Symmetry-Related Electromagnetic Properties of Resonator-Loaded Transmission Lines and Applications

    Directory of Open Access Journals (Sweden)

    Jordi Naqui

    2015-05-01

    Full Text Available This paper reviews the recent progress in the analysis and applications of the symmetry-related electromagnetic properties of transmission lines loaded with symmetric configurations of resonant elements. It will be shown that the transmission characteristics of these reactively loaded lines can be controlled by the relative orientation between the line and the resonant elements. Two main types of loaded lines are considered: (i resonance-based structures; and (ii frequency-splitting structures. In resonance-based transmission lines, a line is loaded with a single resonant (and symmetric element. For a perfectly symmetric structure, the line is transparent if the line and resonator exhibit symmetry planes of different electromagnetic nature (electric or magnetic wall, whereas the line exhibits a notch (resonance in the transmission coefficient if the symmetry planes behave as either electric or magnetic walls (symmetric configuration, or if symmetry is broken. In frequency-splitting lines, paired resonators are typically loaded to the transmission line; the structure exhibits a single notch for the symmetric configuration, whereas generally two split notches appear when symmetry is disrupted. Applications of these structures include microwave sensors (e.g., contactless sensors of spatial variables, selective mode suppressors (of application in common-mode suppressed differential lines, for instance and spectral signature barcodes, among others.

  2. Detection, location, and classification of downed conductors in series-compensated transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Elanien, A.E.B.; Elshatshat, R.; Salama, M.M.A. [Waterloo Univ., ON (Canada); Malik, N. [King Saud Univ., Riyadh (Saudi Arabia)

    2010-07-01

    High impedance faults (HIFs) can occur when the broken conductors of high voltage power transmission lines come into contact with trees or other structures. HIFs typically generate low fault currents that are less, or only slightly higher than normal load currents, and cannot be detected by regular over-current relays. Traditional impedance-based methods of locating HIFs can result in inaccuracies because of the nonlinear behaviour of series capacitor protection arrangements as well as the rapidly changing characteristics of circuit impedances during faults. This study presented an algorithm designed to protect transmission lines against HIFs. The discrete wavelet transform (DWT) method was used to extract the high frequency transients contained in fault currents in order to detect and classify faults. Fault location was conducted using the travelling waves theory. The DWT was used to record the arrival times of the waves at both ends of the transmission line. Simulations conducted to validate the method confirmed that the algorithm was both accurate and reliable. 10 refs., 2 tabs., 12 figs.

  3. Numerical analysis on aeolian vibration of transmission lines with Stockbridge dampers

    Institute of Scientific and Technical Information of China (English)

    LI Li; KONG De-yi; LONG Xiao-hong; FANG Qin-han

    2008-01-01

    We used computational fluid dynamics (CFD) and mode superposition method instead of the energy balance method to compute transmission line aeolian vibrations induced by the Karman vortex. Firstly, we obtained the wind power inputs using CFD theory. The result is effective for aeolian vibration analyses compared with the power which were measured in wind tunnel tests. Then a new aeolian excitation was derived using the wind power equivalent principle, and the aeolian vibration distribution along transmission lines and the wind power input obtained by CFD can be account. Secondly, we formulated the motion equation of a conductor-damper system and derived a semi-analytial solution using the mode superposition method. The Stockbridge-type dampers attached were simplified to the forces transmitted by the clamps. Finally, the semi-analytical solution can be solved by iterative methods. Taking a 1 000 kV Ultra High Voltage transmission line as an example, we analyzed the line with and without dampers by the semi-analytical solution. Compared with the results which were computed by the energy balance method, the semi-analytical solution is precise enogh for aeolian vibration analyses. Besides, we also analyzed the influence of damper position and quantity.

  4. Alleviation SSR and Low Frequency Power Oscillations in Series Compensated Transmission Line using SVC Supplementary Controllers

    Science.gov (United States)

    Kumar, Sanjiv; Kumar, Narendra

    2016-07-01

    In this work, supplementary sub-synchronous damping controllers (SSDC) are proposed for damping sub-synchronous oscillations in power systems with series compensated transmission lines. Series compensation have extensively been used as effective means of increasing the power transfer capability of a transmission lines and improving transient stability limits of power systems. Series compensation with transmission lines may cause sub-synchronous resonance (SSR). The eigenvalue investigation tool is used to ascertain the existence of SSR. It is shown that the addition of supplementary controller is able to stabilize all unstable modes for T-network model. Eigenvalue investigation and time domain transient simulation of detailed nonlinear system are considered to investigate the performance of the controllers. The efficacies of the suggested supplementary controllers are compared on the IEEE first benchmark model for computer simulations of SSR by means of time domain simulation in Matlab/Simulink environment. Supplementary SSDC are considered in order to compare effectiveness of SSDC during higher loading in alleviating the small signal stability problem.

  5. [Study on effects of bioelectric parameters of rats in electromagnetic radiation of HV transmission line].

    Science.gov (United States)

    Zhang, Anying; Pang, Xiaofeng; Yuan, Ping

    2007-02-01

    With the development of economy and coming of information era, the chance of exposure to electromagnetic fields with various frequencies has been increased for every human. The effects of electromagnetic radiattion on human being's health are versatile. To study the effects of bioelctronic parameters of rats in the electromagnetic radiations of HV transmission line, EEG, ECG and CMAP were measured in rats exposed to simulating high-voltage transmission line electromagnetic radiation for over one year. Brain tissues were studied by Fourier transform infrared spectroscopy. The results showed that no significant difference between exposed group and control group in EEG; however the FT-infrared spectra of brain tissues were different; the ECG of the exposed animals was considerably altered. Significant slowing of heart rate was observed in those rates exposed to EMFs; the latent period of CMAP in exposed group were not different compared with those of control group however there was a significant difference in wave amplitude of CMAP between the exposed group and control group. All results indicated that there must be some effects on bioelectric parameters of rats exposed to electromagnetic radiation of high-voltage transmission line for a long time.

  6. A Novel Transient Fault Current Sensor Based on the PCB Rogowski Coil for Overhead Transmission Lines.

    Science.gov (United States)

    Liu, Yadong; Xie, Xiaolei; Hu, Yue; Qian, Yong; Sheng, Gehao; Jiang, Xiuchen

    2016-05-21

    The accurate detection of high-frequency transient fault currents in overhead transmission lines is the basis of malfunction detection and diagnosis. This paper proposes a novel differential winding printed circuit board (PCB) Rogowski coil for the detection of transient fault currents in overhead transmission lines. The interference mechanism of the sensor surrounding the overhead transmission line is analyzed and the guideline for the interference elimination is obtained, and then a differential winding printed circuit board (PCB) Rogowski coil is proposed, where the branch and return line of the PCB coil were designed to be strictly symmetrical by using a joining structure of two semi-rings and collinear twisted pair differential windings in each semi-ring. A serial test is conducted, including the frequency response, linearity, and anti-interference performance as well as a comparison with commercial sensors. Results show that a PCB Rogowski coil has good linearity and resistance to various external magnetic field interferences, thus enabling it to be widely applied in fault-current-collecting devices.

  7. Accurate characterization and modeling of transmission lines for GaAs MMIC's

    Science.gov (United States)

    Finlay, Hugh J.; Jansen, Rolf H.; Jenkins, John A.; Eddison, Ian G.

    1988-06-01

    The authors discuss computer-aided design (CAD) tools together with high-accuracy microwave measurements to realize improved design data for GaAs monolithic microwave integrated circuits (MMICs). In particular, a combined theoretical and experimental approach to the generation of an accurate design database for transmission lines on GaAs MMICs is presented. The theoretical approach is based on an improved transmission-line theory which is part of the spectral-domain hybrid-mode computer program MCLINE. The benefit of this approach in the design of multidielectric-media transmission lines is described. The program was designed to include loss mechanisms in all dielectric layers and to include conductor and surface roughness loss contributions. As an example, using GaAs ring resonator techniques covering 2 to 24 GHz, accuracies in effective dielectric constant and loss of 1 percent and 15 percent respectively, are presented. By combining theoretical and experimental techniques, a generalized MMIC microstrip design database is outlined.

  8. Alleviation SSR and Low Frequency Power Oscillations in Series Compensated Transmission Line using SVC Supplementary Controllers

    Science.gov (United States)

    Kumar, Sanjiv; Kumar, Narendra

    2017-06-01

    In this work, supplementary sub-synchronous damping controllers (SSDC) are proposed for damping sub-synchronous oscillations in power systems with series compensated transmission lines. Series compensation have extensively been used as effective means of increasing the power transfer capability of a transmission lines and improving transient stability limits of power systems. Series compensation with transmission lines may cause sub-synchronous resonance (SSR). The eigenvalue investigation tool is used to ascertain the existence of SSR. It is shown that the addition of supplementary controller is able to stabilize all unstable modes for T-network model. Eigenvalue investigation and time domain transient simulation of detailed nonlinear system are considered to investigate the performance of the controllers. The efficacies of the suggested supplementary controllers are compared on the IEEE first benchmark model for computer simulations of SSR by means of time domain simulation in Matlab/Simulink environment. Supplementary SSDC are considered in order to compare effectiveness of SSDC during higher loading in alleviating the small signal stability problem.

  9. Application Research on Drag Reduced Conductors for Electric Power Transmission Lines in Strong Wind Areas

    Directory of Open Access Journals (Sweden)

    Li Dong Qing

    2016-01-01

    Full Text Available The breeze vibration duration of conductors is long, the vibration amplitude is strong and the frequency range is wide for electric power transmission lines in strong wind areas, which seriously affects the safe and stable operation of transmission lines. There are two design schemes of conductors which can achieve the purpose of reducing wind-induced disaster. One is enhancing the structural strength of conductors to withstand wind load, but the investment is enormous and the effect is limited. The other is developing drag reduced conductors to reduce wind load by changing conductor structure. This paper started from application feasibility analysis of drag reduced conductors and designed four drag reduced conductors by structure optimization of the conventional aluminium conductor steel reinforced JL/G1A-630/45-45/7, denoted as DFY630/45(45°-R3.5, DFY630/45(60°-R3.5, DFY630/45(45°–R3.2 and DFY630/45(60°-R3.2, respectively. The wind tunnel test was performed and the wind resistance coefficients in unit length of five conductors were compared. Result showed that the wind resistance coefficients in unit length of four drag reduced conductors were obviously lower than that of the conventional conductor. By controlling the manufacturing process, popularization and application of drag reduced conductors for transmission lines in strong wind areas can be realized.

  10. CAD model for circuit parameters of superconducting-based hybrid planar transmission lines

    Energy Technology Data Exchange (ETDEWEB)

    Mohebbi, Hamid Reza; Hamed Majedi, A, E-mail: hmohebbi@maxwell.uwaterloo.c, E-mail: ahmajedi@maxwell.uwaterloo.c [Integrated Quantum Optoelectronics Lab (IQOL), Department of ECE, Institute for Quantum Computing (IQC), University of Waterloo, Waterloo, N2L 3G1 (Canada)

    2009-12-15

    Using the concept of surface impedance associated with a superconductor or normal conductor's plate, we extend the CAD (computer aided design) formalisms on modeling and simulation of superconducting and normal transmission lines (STL and NTL) in order to include hybrid transmission lines (HTL). STL and NTL are entirely made of superconductor or normal conductor materials, respectively. In this paper, HTL refers to a planar transmission line (TL) such as parallel plate (PPTL), microstrip ({mu}TL) and coplanar waveguide (CPW) whose ground plate is superconducting and whose top/center strip is a normal conductor or vice versa. We develop and present a set of closed-form equations in a tidy and succinct form for each configuration (STL, NTL and HTL) for widely-used planar TLs (PPTL, {mu}TL and CPW). They can be easily implemented in a systematic way by the user for the purpose of fast TL design. The results obtained with this CAD tool are compared with previously reported results in the literature, and good agreement is observed.

  11. Propagation and localization of quantum dot emission along a gap-plasmonic transmission line.

    Science.gov (United States)

    Castro-Lopez, M; Manjavacas, A; García de Abajo, J; van Hulst, N F

    2015-11-16

    Plasmonic transmission lines have great potential to serve as direct interconnects between nanoscale light spots. The guiding of gap plasmons in the slot between adjacent nanowire pairs provides improved propagation of surface plasmon polaritons while keeping strong light confinement. Yet propagation is fundamentally limited by losses in the metal. Here we show a workaround operation of the gap-plasmon transmission line, exploiting both gap and external modes present in the structure. Interference between these modes allows us to take advantage of the larger propagation distance of the external mode while preserving the high confinement of the gap mode, resulting in nanoscale confinement of the optical field over a longer distance. The performance of the gap-plasmon transmission line is probed experimentally by recording the propagation of quantum dots luminescence over distances of more than 4 μm. We observe a 35% increase in the effective propagation length of this multimode system compared to the theoretical limit for a pure gap mode. The applicability of this simple method to nanofabricated structures is theoretically confirmed and offers a realistic way to combine longer propagation distances with lateral plasmon confinement for far field nanoscale interconnects.

  12. A Novel Transient Fault Current Sensor Based on the PCB Rogowski Coil for Overhead Transmission Lines

    Directory of Open Access Journals (Sweden)

    Yadong Liu

    2016-05-01

    Full Text Available The accurate detection of high-frequency transient fault currents in overhead transmission lines is the basis of malfunction detection and diagnosis. This paper proposes a novel differential winding printed circuit board (PCB Rogowski coil for the detection of transient fault currents in overhead transmission lines. The interference mechanism of the sensor surrounding the overhead transmission line is analyzed and the guideline for the interference elimination is obtained, and then a differential winding printed circuit board (PCB Rogowski coil is proposed, where the branch and return line of the PCB coil were designed to be strictly symmetrical by using a joining structure of two semi-rings and collinear twisted pair differential windings in each semi-ring. A serial test is conducted, including the frequency response, linearity, and anti-interference performance as well as a comparison with commercial sensors. Results show that a PCB Rogowski coil has good linearity and resistance to various external magnetic field interferences, thus enabling it to be widely applied in fault-current-collecting devices.

  13. Application of Six-Sequence Fault Components in Fault Location for Joint Parallel Transmission Line

    Institute of Scientific and Technical Information of China (English)

    FAN Chunju; CAI Huarong; YU Weiyong

    2005-01-01

    A new fault location method based on six-sequence fault components was developed for parallel lines based on the fault analysis of a joint parallel transmission line. In the six-sequence fault network, the ratio of the root-mean square value of the fault current from two terminals is the function of the line impedance, the system impedance, and the fault distance away from the buses. A fault location equation is given to relate these factors. For extremely long transmission lines, the distributed capacitance is divided by the fault point and allocated to the two terminals of the transmission line in a lumped parameter to eliminate the influence of the distributed capacitance on the location accuracy. There is no limit on fault type and synchronization of the sampling data. Simulation results show that the location accuracy is high with an average error about 2%, and it is not influenced by factors such as the load current, the operating mode of the power system, or the fault resistance.

  14. Backpropagation Neural Network Modeling for Fault Location in Transmission Line 150 kV

    Directory of Open Access Journals (Sweden)

    Azriyenni Narwan

    2014-03-01

    Full Text Available In this topic research was provided about the backpropagation neural network to detect fault location in transmission line 150 kV between substation to substation. The distance relay is one of the good protective device and safety devices that often used on transmission line 150 kV. The disturbances in power system are used distance relay protection equipment in the transmission line. However, it needs more increasing large load and network systems are increasing complex. The protection system use the digital control, in order to avoid the error calculation of the distance relay impedance settings and spent time will be more efficient. Then backpropagation neural network is a computational model that uses the training process that can be used to solve the problem of work limitations of distance protection relays. The backpropagation neural network does not have limitations cause of the impedance range setting. If the output gives the wrong result, so the correct of the weights can be minimized and also the response of galat, the backpropagation neural network is expected to be closer to the correct value. In the end, backpropagation neural network modeling is expected to detect the fault location and identify operational output current circuit breaker was tripped it. The tests are performance with interconnected system 150 kV of Riau Region.

  15. Corona noise model of high-voltage AC transmission lines and engineering applications

    Institute of Scientific and Technical Information of China (English)

    Wu Jiuhui; Di Zelong

    2013-01-01

    In order to predict the levels of corona noise from high-voltage alternating current (AC) transmission lines,the mechanism of corona noise and the corresponding theoretical prediction model are investigated.On the basis of Drude model,the motion of positive and negative ions produced by high-voltage corona is analyzed,and the mechanism of corona noise is discovered.The theoretical prediction model is put forward by using Kirchhoff formula,which is verified by the well agreement between our result and others',considering the case of three-phase single lines.Moreover,the calculation results show that for both single and bundled lines,the sound pressure level of the typical frequency,i.e.twice the power frequency,attenuates slowly and leads to an obviously interferential phenomenon near the transmission lines,but the level of the bundled lines is smaller than that of the single ones under the same transmission voltage.Based on the mechanism of corona noise and the prediction model,it is obvious that bundled lines and/or increased line radius can be adopted to reduce corona noise in the practical engineering applications effectively.This model can also provide a theoretical guidance for the high-volt-age AC transmission line design.

  16. Volumetric Virtual Environments

    Institute of Scientific and Technical Information of China (English)

    HE Taosong

    2000-01-01

    Driven by fast development of both virtual reality and volume visualization, we discuss some critical techniques towards building a volumetric VR system, specifically the modeling, rendering, and manipulations of a volumetric scene.Techniques such as voxel-based object simplification, accelerated volume rendering,fast stereo volume rendering, and volumetric "collision detection" are introduced and improved, with the idea of demonstrating the possibilities and potential benefits of incorporating volumetric models into VR systems.

  17. Environmental Assessment of the Gering-Stegall 115-kV Transmission Line Consolidation Project, Scotts Bluff County, Nebraska

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    The Department of Energy (DOE), Western Area Power Administration (Western) proposes to consolidate segments of two transmission lines near the Gering Substation in Gering, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska. The transmission lines are both located in Scotts Bluff County, Nebraska, within the city of Gering. Presently, there are three parallel 115-kilovolt (kV) transmission lines on separate rights-of-way (ROW) that terminate at the Gering Substation. The project would include dismantling the Archer-Gering wood-pole transmission line and rebuilding the remaining two lines on single-pole steel double circuit structures. The project would consolidate the Gering-Stegall North and Gering-Stegall South 115-kV transmission lines on to one ROW for a 1.33-mile segment between the Gering Substation and a point west of the Gering Landfill. All existing wood-pole H-frame structures would be removed, and the Gering-Stegall North and South ROWs abandoned. Western is responsible for the design, construction, operation, and maintenance of the line. Western prepared an environmental assessment (EA) that analyzed the potential environmental impacts of the proposed construction, operation, and maintenance of the 115-kV transmission line consolidation. Based on the analyses in the EA, the DOE finds that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act of 1969 (NEPA).

  18. Analysis on Lighting Withstand Characteristics of Polymeric ZnO Surge Arrester for Transmission Line against Lightning Overvoltages

    Energy Technology Data Exchange (ETDEWEB)

    Han, S.W.; Cho, H.G. [Korea Electrotechnology Research Institute, Changwon (Korea); He, J.L. [Tsinghua University, Beijing (Switzerland)

    2000-02-01

    The purpose of this study is to discuss the lightning withstand levels (LWLs) of two 110 kV transmission lines before and after line arresters made with polymeric housing are installed on the towers, the lightning discharging currents through arresters and lightning energies absorbed by line arresters. The LWLs can be highly increased by installing line arresters on the transmission line towers in parallel with the insulator strings. It is not problem that the polymeric ZnO surge arresters are used in transmission lines to limit lightning overvoltages. (author). 9 refs., 11 figs., 1 tab.

  19. Position Measurements with Micro-Channel Plates and Transmission lines using Pico-second Timing and Waveform Analysis

    CERN Document Server

    Adamsa, Bernhard; Bogdan, Mircea; Byrum, Karen; Genat, Jean-Francois C; Grabas, Herve; Frisch, Henry J; Kim, Heejong; Heintz, Mary K; Natoli, Tyler; Northrop, Richard; Oberla, Eric; Meehan, Samuel; May, Edward N; Stanek, Robert; Tang, Fukun; Varner, Gary; Yurtsev, Eugene

    2009-01-01

    The anodes of Micro-Channel Plate devices are coupled to fast transmission lines in order to reduce the number of electronics readout channels, and can provide two-dimension position measurements using two-ends delay timing. Tests with a laser and digital waveform analysis show that resolutions of a few hundreds of microns along the transmission line can be reached taking advantage of a few pico-second timing estimation. This technique is planned to be used in Micro-channel Plate devices integrating the transmission lines as anodes.

  20. The quantum Kirchhoff equation and quantum current and energy spectrum of a homogeneous mesoscopic dissipation transmission line

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    On the basis of quantization of charge, the loop equations of quantum circuits are investigated by using the Heisenberg motion equation for a mesoscopic dissipation transmission line. On the supposition that the system has a symmetry under translation in charge space, the quantum current and the quantum energy spectrum in the mesoscopic transmission line are given by solving their eigenvalue equations. Results show that the quantum current and the quantum energy spectrum are not only related to the parameters of the transmission line, but also dependent on the quantized character of the charge obviously.

  1. Transmission Lines or Poles, Electric, Locations of Transmission lines for our reference. Engineering accurate data available from Sunflower Electric., Published in 2003, 1:24000 (1in=2000ft) scale, Prairie Land Electric COOP, Inc..

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Field Observation information as of...

  2. Estimation of Switching Overvoltages on Transmission Lines Using Neuro-Fuzzy Method

    Directory of Open Access Journals (Sweden)

    Reza Shariatinasab

    2012-11-01

    Full Text Available Insulation failure caused by switching overvoltages (SOVs is one of the main sources of transmission lines’ outage, specially, on voltage levels of 345 kV and above. Therefore, the estimation of SOVs is vital in order to control and/or to reduce the switching–related outages. Due to the stochastic behavior of some of the parameters affecting on SOVs, the study of this phenomenon should be carried out based on a statistical study of the switching. Also, in the case of surge arrester installation on the transmission lines, depending on the location of arrester, voltage profile on line is changed and all the simulation should be performed for each new location of arresters, separately. One can conclude that this procedure is complex and time consuming. In this paper, a fuzzy based meta-model is presented which is be able to estimate the switching surge flashover rate (SSFOR, the maximum value of SOVs on the network and the location where the maximum overvoltage takes place. In the proposed meta model, the effect of altitude on SSFOR and the magnitude of SOVs is considered. This meta-model can be used, directly, for planning the insulation level of transmission lines in order to meet a certain number of outages and locating arresters on the region/nodes of the network of weak operation against SOVs. It is also possible to utilize the proposed meta model, indirectly, for assigning the optimal location of any specified set of arresters on the network without simulating of real network by a transient software, e.g. EMTP/ATP draw. The presented meta model can also be used in the operating stage to decide on the sequence of energizing and re-energizing of different transmission lines connected to the substations with the aim of reducing of maximum SOVs.

  3. UAV-Based Oblique Photogrammetry for Outdoor Data Acquisition and Offsite Visual Inspection of Transmission Line

    Directory of Open Access Journals (Sweden)

    San Jiang

    2017-03-01

    Full Text Available Regular inspection of transmission lines is an essential work, which has been implemented by either labor intensive or very expensive approaches. 3D reconstruction could be an alternative solution to satisfy the need for accurate and low cost inspection. This paper exploits the use of an unmanned aerial vehicle (UAV for outdoor data acquisition and conducts accuracy assessment tests to explore potential usage for offsite inspection of transmission lines. Firstly, an oblique photogrammetric system, integrating with a cheap double-camera imaging system, an onboard dual-frequency GNSS (Global Navigation Satellite System receiver and a ground master GNSS station in fixed position, is designed to acquire images with ground resolutions better than 3 cm. Secondly, an image orientation method, considering oblique imaging geometry of the dual-camera system, is applied to detect enough tie-points to construct stable image connection in both along-track and across-track directions. To achieve the best geo-referencing accuracy and evaluate model measurement precision, signalized ground control points (GCPs and model key points have been surveyed. Finally, accuracy assessment tests, including absolute orientation precision and relative model precision, have been conducted with different GCP configurations. Experiments show that images captured by the designed photogrammetric system contain enough information of power pylons from different viewpoints. Quantitative assessment demonstrates that, with fewer GCPs for image orientation, the absolute and relative accuracies of image orientation and model measurement are better than 0.3 and 0.2 m, respectively. For regular inspection of transmission lines, the proposed solution can to some extent be an alternative method with competitive accuracy, lower operational complexity and considerable gains in economic cost.

  4. Estimating magnetic fields of homes near transmission lines in the California Power Line Study.

    Science.gov (United States)

    Vergara, Ximena P; Kavet, Robert; Crespi, Catherine M; Hooper, Chris; Silva, J Michael; Kheifets, Leeka

    2015-07-01

    The California Power Line Study is a case-control study investigating the relation between residences near transmission lines and risk of childhood leukemia. It includes 5788 childhood leukemia cases and 5788 matched primary controls born between 1986 and 2007. We describe the methodology for estimating magnetic fields at study residences as well as for characterizing sources of uncertainty in these estimates. Birth residences of study subjects were geocoded and their distances to transmission lines were ascertained. 302 residences were deemed sufficiently close to transmission lines to have non-zero magnetic fields attributable to the lines. These residences were visited and detailed data, describing the physical configuration and dimensions of the lines contributing to the magnetic field at the residence, were collected. Phasing, loading, and directional load flow data for years of birth and diagnosis for each subject as well as for the day of site visit were obtained from utilities when available; when yearly average load for a particular year was not available, extrapolated values based on expert knowledge and prediction models were obtained. These data were used to estimate the magnetic fields at the center, closest and farthest point of each residence. We found good correlation between calculated fields and spot measurements of fields taken on site during visits. Our modeling strategies yielded similar calculated field estimates, and they were in high agreement with utility extrapolations. Phasing was known for over 90% of the lines. Important sources of uncertainty included a lack of information on the precise location of residences located within apartment buildings or other complexes. Our findings suggest that we were able to achieve high specificity in exposure assessment, which is essential for examining the association between distance to or magnetic fields from power lines and childhood leukemia risk.

  5. Final environmental assessment: Los Reales 115 kV transmission line alternative routes

    Energy Technology Data Exchange (ETDEWEB)

    1989-10-01

    The Central Arizona Project (CAP) was authorized as a part of the Colorado River Basin Project Act (Public Law 90-537) on September 30, 1968. The primary purpose of the CAP is to furnish water for agricultural, municipal, and industrial uses in central and southern Arizona, and western New Mexico. Due to its magnitude, the CAP is divided into several major features serving separate but interrelated functions. The Tucson Aqueduct Phase B pumping plants were designed and constructed to operate on a looped power system. The entire looped power system, including two switching stations and connecting 115-kv transmission lines, was identified in the FEIS and approved for construction in the Secretary of Interior's Record of Decision dated September 24, 1985. The loop begins in the vicinity of the Twin Peaks Pumping Plant -- the northernmost Phase B pumping station, at the Rattlesnake Switching Station. All of the looped power system has been constructed with the exception of the switching station and portion of transmission line proposed to be constructed in this project. Without construction of this final portion of the looped power system, the Phase B pumping plants will not be able to operate normally without negatively affecting nearby power sources. The CAP will also not be able to provide the reliability necessary for municipal water systems dependent upon CAP water. The purpose of this EA is to describe impacts that would result from relocating the Los Reales 115-kV transmission line, and possibly the switching station, originally identified in the FEIS. It should be mentioned the Department of Energy will complete a separate NEPA review.

  6. Deicing of medium voltage power transmission lines by Joule heating method

    Energy Technology Data Exchange (ETDEWEB)

    Farokhi, S.; Vahidi, B. [Amirkabir Univ. of Technology, Tehran (Iran, Islamic Republic of). Electrical Engineering Dept.

    2005-07-01

    A Joule heating method for the de-icing of overhead transmission lines was presented. The combined use of short circuits and reduced voltage was introduced as as effective method for the de-icing of sub-transmission lines of a utility in Iran. The method is able to melt ice in a short period of time. The required electrical current and the time needed for melting the ice as a function of wind speed, air temperature and ice thickness was determined by using a finite difference heat transfer model which considered the heat flux terms. An algorithm of the application method was proposed using the finite difference heat transfer model and considering steady state radial heat conduction. The required time for melting the accumulated ice on overhead transmission lines for different values of line current and climatic conditions was calculated. In the proposed method, after disconnecting the end of the line, a 3 phase short circuit was applied and accumulated ice was melted because of Joule losses. The main restrictions to the method were the current rating of facilities, and source capacity. After a consideration of these restrictions, instead of feeding the line by rated voltage, a voltage with a value of about 20 to 40 per cent of its rated voltage was applied and a short circuit on the end of the line should be made. The algorithm was made by collecting the data for the power system, disconnecting both ends of the line from the system and applying required changes on loads. transformers calculated from the load flow of the system. The line was fed with the reduced voltage by connecting the line to a lower level voltage. A case study of the method was presented. 10 refs., 1 tab., 4 figs.

  7. Analysis of the ITER low field side reflectometer transmission line system.

    Science.gov (United States)

    Hanson, G R; Wilgen, J B; Bigelow, T S; Diem, S J; Biewer, T M

    2010-10-01

    A critical issue in the design of the ITER low field side reflectometer is the transmission line (TL) system. A TL connects each launcher to a diagnostic instrument. Each TL will typically consist of ∼42 m of corrugated waveguide and up to ten miter bends. Important issues for the performance of the TL system are mode conversion and reflections. Minimizing these issues are critical to minimizing standing waves and phase errors. The performance of TL system is analyzed and recommendations are given.

  8. Impacts of transmission lines on birds in flight: proceedings of a workshop

    Science.gov (United States)

    Avery, Michael L.

    1978-01-01

    Progress to alleviate the national and world energy problem will come as individual issues are identified and acceptable solutions implemented. One of the specific issues to emerge in the last few years in the United States is the impact of electric power transmission lines on birds in flight. Therefore, the National Power Plant Team, Office of Biological Services, U.S. Fish and Wildlife Service, requested Oak Ridge Associated Universities (ORAU) to organized and convene a workshop of knowledgeable experts to examine this issue and options for dealing with it. The participants are listed at the end of this report.

  9. Examination of Height of Transmission Line and Lightning Striking Distance concerning Lightning Shielding Effect Prediction

    Science.gov (United States)

    Sakata, Tadashi; Yamamoto, Kazuo; Sekioka, Shozo; Yokoyama, Shigeru

    We examined the lightning frequency reported by Eriksson and the lightning current distribution shown in IEC 62305-1. The lightning striking coefficient is assumed to be related to height of structures. The lightning current distribution to ground which was applicable to the electro-geometric model is estimated. Using the assumption of lightning striking distance coefficient and the estimated lightning current distribution, we calculated the lightning frequency and the lightning current distribution, concerning lightning shielding effect in transmission lines. The calculation results of the lightning frequency and the lightning current distributions were compared with the observation results, and agree satisfactorily with them.

  10. Analytical Formulation for Electromagnetic Leakage Field to Transmission Line Coupling through Covered Apertures of Multiple Enclosures

    Directory of Open Access Journals (Sweden)

    Jianhong Hao

    2017-01-01

    Full Text Available An efficient analytical model has been developed for predicting the electromagnetic leakage field coupling with a lossless two-conductor transmission line (TL through covered apertures of multiple enclosures. The analytical results have been successfully compared with those from the full-wave simulation software CST over a broad frequency range. The analytical model can be employed to analyze the effect of different factors including the position and the direction of the electric dipole, the conductivity of the conductive sheet, the quantity of the aperture, and the direction of the TL on the induced currents. Besides, it can also deal with apertures in multiple sides of the enclosures.

  11. Research on Line Patrol Strategy of 110kV Transmission Line after Lightning Strike

    Directory of Open Access Journals (Sweden)

    Li Mingjun

    2016-01-01

    Full Text Available Lightning faults occupy in the majority of instantaneous fault and reclosing can usually be successful, so power supply can be restored without immediate patrol in many cases. Firstly, this paper introduces the lightning fault positioning and identifying method. Then test electrical performance of insulators after lightning strike from 110kV lines. Data shows that lightning strike has little effect on the electric performance of insulator. Finally, illustrating disposal process of the 110 kV transmission line after lightning fault, certifying that the power supply reliability be ensured without line patrol.

  12. Sidney-North Yuma 230-kV Transmission Line Project, Colorado and Nebraska

    Energy Technology Data Exchange (ETDEWEB)

    1991-06-01

    This report describes the need for a 230-kV overhead transmission line to supply power from Sidney, Nebraska to eastern Colorado. The alternative scenario compared to construction of the line is No Action. Rejected alternatives include underground lines and different routing paths, with a possible extension to the Sterling area. Both scenarios are evaluated for environmental effects, cost, and consequences for the eastern Colorado region. The proposed route is determined to be the environmentally preferred choice. 120 refs., 6 figs., 13 tabs. (MHB)

  13. Numerical analysis of ionized fields associated with HVDC transmission lines including effect of wind

    Energy Technology Data Exchange (ETDEWEB)

    Li, X.

    1998-12-31

    The effects of corona discharge on the conductor surface of HVDC power transmission lines were studied. Corona discharges generate ion flow and can cause power losses and environmental concerns. Solving the problem of the ion flow field is difficult because of its nonlinearity and the effect of wind. The following two numerical algorithms were presented which address the problem associated with strong wind or bundled lines: (1) the finite element method (FEM) based optimization algorithm, and (2) the upwind FVM based relaxation algorithm. Both were successfully tested on a coaxial cylindrical configuration and on a unipolar line model in the presence of wind.

  14. Determining the Time Dependence of Electrical Gradients in Railguns Using the Transmission Line Model

    Science.gov (United States)

    2008-12-01

    The Feynman Lectures in Physics vol II, 3rd ed. Addison Wesley, 238 pp. Kerrisk, J.F., 1981: Current Distribution and Inductance Calculations for...sides of Eq. (1) gives: ∂V(x,t) /∂x = - LX (t)di(t)/dt-2RX(t)i(t) (2) This is similar to the familiar transmission line equation ( Feynman ...relatively insensitive to time. We attribute this to fundamental differences in the physics of the two processes. The IR voltages are a function of the

  15. Electromagnetic Field Interaction With Transmission Lines From Classical Theory to HF Radiation Effects

    CERN Document Server

    Tkachenko, Sergey V

    2008-01-01

    The evaluation of the electromagnetic field coupling to transmission lines is an important problem in electromagnetic compatibility. The unabated increase in the operating frequency of electronic products and the emergence of sources of disturbances with higher frequency content (such as High Power Microwave and Ultra-Wide Band systems) have led to a breakdown of the TL approximation's basic assumptions for a number of applications. In the last decade or so, the generalization of the TL theory to take into account high frequency effects has emerged as an important topic of study in electromagn

  16. TWO APPROACHES TO CALCULATION OF SPLIT PHASE DANCING OF OVERHEAD ELECTRICAL TRANSMISSION LINE

    Directory of Open Access Journals (Sweden)

    I. I. Sergey

    2005-01-01

    Full Text Available The paper shows two approaches to mathematical modeling of split phase dancing of overhead electrical transmission line. The first approach is based on calculative method when a phase is in the shape of flexible elastic thread connected with rigid rods. The phase is represented with equivalent wire in the second approach. Principle of mechanics relations has been used to set combined boundary problem of split phase dynamics. Two packets of computer programs for calculation of split phase dancing of overhead (electric power line have been set up and tested.

  17. Optimal Placement of Unified Power Flow Controllers : An Approach to Maximize the Loadability of Transmission Lines

    Directory of Open Access Journals (Sweden)

    S. T. Jaya Christa

    2006-06-01

    Full Text Available This paper deals with the optimal location and parameters of Unified Power Flow Controllers (UPFCs in electrical power systems, using particle swarm optimization (PSO. The objective is to maximize the transmission system loadability subject to the transmission line capacity limits and specified bus voltage levels. Using the proposed method, the location of UPFCs and their parameters are optimized simultaneously. PSO is used to solve the above non-linear programming problem for better accuracy. The proposed approach is examined and tested on IEEE 30-bus system and IEEE 118-bus system. The results obtained are quite promising for the power system operation environment

  18. Design and Manufacture of the RF Power Supply and RF Transmission Line for SANAEM Project Prometheus

    CERN Document Server

    Turemen, G; Unel, G; Alacakir, A

    2015-01-01

    A 1-5 MeV proton beamline is being built by the Turkish Atomic Energy Authority in collaboration with a number of graduate students from different universities. The most important aspect of the project, is to acquire the design ability and manufacturing capability of all the components locally. SPP will be an accelerator and beam diagnostics test facility and it will also serve the detector development community with its low beam current. This paper discusses the design and construction of the RF power supply and the RF transmission line components such as its waveguide converters and its circulator.

  19. Simulating Entanglement Dynamics of Singlet-Triplet Qubits Coupled to a Classical Transmission Line Resonator

    Science.gov (United States)

    Wolfe, Michael; Kestner, Jason

    Electrons confined in lateral quantum dots are promising candidates for scalable quantum bits. Particularly, singlet-triplet qubits can entangle electrostatically and offer long coherence times due to their weak interactions with the environment. However, fast two-qubit operations are challenging. We examine the dynamics of singlet triplet qubits capacitively coupled to a classical transmission line resonator driven near resonance. We numerically simulate the dynamics of the von Neumann entanglement entropy and investigate parameters of the coupling element that optimizes the operation time for the qubit.

  20. Nonlinear properties of the lattice network-based nonlinear CRLH transmission lines

    Institute of Scientific and Technical Information of China (English)

    王正斌; 吴昭质; 高超

    2015-01-01

    The nonlinear properties of lattice network-based (LNB) composite right-/left-handed transmission lines (CRLH TLs) with nonlinear capacitors are experimentally investigated. Harmonic generation, subharmonic generation, and parametric excitation are clearly observed in an unbalanced LNB CRLH TL separately. While the balanced design of the novel nonlinear TL shows that the subharmonic generation and parametric processes can be suppressed, and almost the same power level of the higher harmonics can be achieved over a wide bandwidth range, which are difficult to find in the conventional CRLH TLs.

  1. Serial Failure Diagnosis of a Transmission Line Protection Relaying System by Petri Nets

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    With the development of large-scale complicated modern power systems, the requirement for the associatedprotection scheme tends to be more stringent and its combination more complex. However, it is very difficult to figureout the factors of failure of such systems. This paper proposes a Petri net model of a transmission line protectionrelaying system, including three types of relays as well as an automatic re-closing device, and shows how to diagnoseserial failure of the system by analyzing invariant sets of the model. Furthermore, it gives four basic types of failuresequences and its execution is much more intuitive and effective than the traditional method.

  2. Design and optimization of the PBFA 2 vacuum interface and transmission lines for light ion fusion

    Science.gov (United States)

    McDaniel, D. B.; Stinnett, R. W.; Gray, E. W.

    1985-03-01

    The PBFA II vacuum insulator was originally designed for optimum coupling to a proton ion diode with minimum inductance. In July 1983 it was decided that lithium ions at 30 MeV would be the baseline for PBFA II. This requires the use of plasma opening switches (POS) and vacuum inductor to reach 30 MV. To achieve this, the vacuum magnetically insulated transmission lines had to be redesigned as an inductive energy store. To gain optimum coupling to this vacuum inductors, the output impedance of the water section was increased by the use of a water-dielectric transformer. The calculations leading to the final design will be discussed.

  3. Negative Group Velocity Pulse Propagation Through a Left-Handed Transmission Line

    CERN Document Server

    Jiang, Rong; Miao, Jing-Yuan; Liu, Xin-Meng

    2015-01-01

    In this paper, the microwave pulse propagation transferred through a left-handed transmission line using Complementary Omega-Like Structures (COLS) loaded was studied. There was a stop band in transmission from 5.6GHz to 6.1GHz, and the anomalous dispersion was causes in this band. Negative group velocity corresponds to the case in which the peak of the pulse exited before the peak of the incident pulse had entered the sample. The negative group velocity reached (-0.27c~-1.85c).

  4. Modeling of Multilayer Transmission Lines for High-Speed Digital Interconnects

    Directory of Open Access Journals (Sweden)

    Sarhan M. Musa,

    2015-08-01

    Full Text Available In this paper, we consider the finite element modeling of multilayer transmission lines for high-speed digital interconnects. We mainly focused on the modeling of the transmission structures with both cases of symmetric and asymmetric geometries. We specifically designed asymmetric coupled microstrips and four-line symmetric coupled microstrips with a two-layer substrate. We computed the capacitance matrix for asymmetric coupled microstrips and the capacitance, inductance, and impedance matrices for four-line symmetric coupled microstrips on a two-layer substrate. We also provide the potential distribution spectrums of the models and their meshing analysis.

  5. Accurate Modeling of Multilayer Transmission Lines for High-Speed Digital Interconnects

    Directory of Open Access Journals (Sweden)

    Sarhan M. Musa

    2014-03-01

    Full Text Available In this paper, we consider the finite element modeling of multilayer transmission lines for high-speed digital interconnects. We mainly focused on the modeling of the transmission structures with both cases of symmetric and asymmetric geometries. We specifically designed asymmetric coupled microstrips and four-line symmetric coupled microstrips with a two-layer substrate. We computed the capacitance matrix for asymmetric coupled microstrips and the capacitance, and inductance matrices for four-line symmetric coupled microstrips on a twolayer substrate. We also provide the potential distribution spectrums of the models.

  6. Broadband Impedance Transformer Based on Asymmetric Coupled Transmission Lines in Nonhomogeneous Medium

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Krozer, Viktor; Meincke, Peter

    2007-01-01

    A new broadband quarter-wavelength impedance transformer based on an asymmetric coupled line section is presented. The bandwidth of the coupled line transformer is extended with the help of an interconnecting transmission line. An analytical model for the transformer is developed. The analysis...... of the structure reveals that a fractional bandwidth of more than 100% at –20 dB reflection level can be achieved with such a structure. An experimental transformer circuit has been designed, fabricated and tested. Theoretical and experimental results are fair agreement and confirm the established theory...

  7. Transmission Lines or Poles, Electric, upl line, Published in 2005, 1:24000 (1in=2000ft) scale, Iron County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2005. It is...

  8. Transmission Lines or Poles, Electric, Underground Electric Lines, Published in unknown, North Georgia College and State University.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, was produced all or in part from Field Survey/GPS information as of unknown. It is described as 'Underground...

  9. Transmission Lines or Poles, Electric, transfrm, Published in 2005, 1:24000 (1in=2000ft) scale, Iron County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2005. It is...

  10. Transmission Lines or Poles, Electric, Utahpowerlines, Published in 2005, 1:24000 (1in=2000ft) scale, Carbon County GIS.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2005. It is...

  11. A new model for induced voltage calculations in power transmission lines; Novo modelo para calculo de tensao induzida em LT's

    Energy Technology Data Exchange (ETDEWEB)

    Silveira, Fernando Henrique; Schroeder, Marco Aurelio de O.; Visacro Filho, Silverio; Soares Junior, Amilton [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Lightning Research Center - Nucleo de Desenvolvimento Cientifico e Tecnologico em Descargas Atmosfericas]. E-mail: lrc@cpdee.ufmg.br

    2001-07-01

    In this document the authors present the previous results of accomplished simulations through a brand new model to calculate the induced voltage by atmospheric discharges on power transmission lines. Through geometric data variation from the transmission line and discharge parameters, it is executed a sensibility analysis concerning to the relevant factors in order to define the levels of induced voltage in the transmission line. Finally, the work aims to evaluate this phenomenon importance in connection with 138 kv transmission lines.

  12. A General Equation Derived by Field Theory for the Use of Uniform Transmission Line with Mutual Inductance

    Institute of Scientific and Technical Information of China (English)

    HONGQingquan; WANGJiancheng; CHENShennian

    2004-01-01

    Beginning with 2 independent equations in integral form derived from Maxwell equation, a most general equation is inferred for the use of uniform transmission line where mutual inductance exists between two conductors in all different line segments of unit lengths;and moreover, the formulas of the magnitude of parameters are given for the use of line segments of unit length on uniform transmission line. A method of field theory is thus offered for analyzing distributed parameter circuit.

  13. Microwave properties of monolithic Y-Ba-Cu-O transmission line devices fabricated by the laser-writing patterning technique

    Energy Technology Data Exchange (ETDEWEB)

    Maung, W.N.; Butler, D.P. [Southern Methodist Univ., Dallas, TX (United States). Electrical Engineering Dept.; Xiong, W. [Univ. of Rochester, NY (United States). Dept. of Electrical Engineering; Kula, W.; Sobolewski, R. [Univ. of Rochester, NY (United States). Dept. of Electrical Engineering]|[Polish Academy of Sciences, Warszawa (Poland). Inst. of Physics

    1994-12-31

    The authors report on the microwave characteristics of coplanar strip transmission line devices fabricated in epitaxial YBaCuO thin films deposited on LaAlO{sub 3} substrates using the novel laser-writing patterning technique. This technique uses laser heating to selectively anneal regions of an oxygen depleted YBaCuO thin film to form local superconducting phases. In this manner, superconductive coplanar strip transmission line structures surrounded by the semiconducting YBaCuO phase were patterned with no photomasks, surface contamination or edge degradation. The propagation characteristics of transmission line devices were measured with a HP8510 network analyzer from 1 to 20 GHz. At 300 K, the transmission line circuits displayed poor transmission characteristics due to the high conductivity of the semiconducting phase and small conductivity enhancement of the oxygenated regions. As the circuits were cooled below 89 K, the {Tc} of the superconducting phase, the measured S{sub 21} was near 0 dB indicating little attenuation along the high quality transmission lines. Q-factors as high as 5,000 were measured from coplanar strip transmission line resonator circuits at 6 GHz and 24 K.

  14. Transmission Lines or Poles, Electric, Electricity Transmission Lines; electran; Major above ground high voltage electrical transmission lines as shown on USGS 7.5 minute topo quads and/or as confirmed through identification of visible right of way cuts on digital orthophotgraphy., Published in 2001, 1:4800 (1in=400ft) scale, State of Rhode Island and Providence Plantations.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Orthoimagery information as of 2001. It...

  15. Support vector machine based fault classification and location of a long transmission line

    Directory of Open Access Journals (Sweden)

    Papia Ray

    2016-09-01

    Full Text Available This paper investigates support vector machine based fault type and distance estimation scheme in a long transmission line. The planned technique uses post fault single cycle current waveform and pre-processing of the samples is done by wavelet packet transform. Energy and entropy are obtained from the decomposed coefficients and feature matrix is prepared. Then the redundant features from the matrix are taken out by the forward feature selection method and normalized. Test and train data are developed by taking into consideration variables of a simulation situation like fault type, resistance path, inception angle, and distance. In this paper 10 different types of short circuit fault are analyzed. The test data are examined by support vector machine whose parameters are optimized by particle swarm optimization method. The anticipated method is checked on a 400 kV, 300 km long transmission line with voltage source at both the ends. Two cases were examined with the proposed method. The first one is fault very near to both the source end (front and rear and the second one is support vector machine with and without optimized parameter. Simulation result indicates that the anticipated method for fault classification gives high accuracy (99.21% and least fault distance estimation error (0.29%.

  16. Transmission line of 1MV in natural parks. Environmental survey relating to the construction

    Energy Technology Data Exchange (ETDEWEB)

    Uesugi, Tetsuro (Environmental Agency, Tokyo (Japan))

    1989-03-31

    Tokyo Electric Power Co., Ltd.(TEPCO) determined to construct a new transmission line of 1MV and 250km long from a power station facing the Japan Sea (Niigata Pref.) to the Pacific Ocean side(Yamanashi Pref.). It is realistically difficult to construct the transmission line, avoiding perfectly the natural park regions located in the middle part of the Main Island, and therefore many kinds of environmental survey were carried out from the beginning of the plan to minimize hindrances to these natural parks. The Environment Agency summarized the outline to use as the reference to similar constructions. Following surveys or assessments were conducted: planning assessment to minimize influences on natural parks in the route selecting stage; executing assessment to evaluate influences of concrete constructing contents such as tower locations and scale, etc. on the natural environment; fundamental survey to grasp outline of the natural parks or maintaining countermeasures carried out before or parallel to these assessments; and finally survey during the construction and the subsequent surveys until the suitable time after the completion to check the influence. 2 figs., 4 tabs.

  17. Analysis of transmission lines loaded with pairs of coupled resonant elements and application to sensors

    Energy Technology Data Exchange (ETDEWEB)

    Naqui, J.; Su, L., E-mail: lijuan.suri.su@gmail.com; Mata, J.; Martín, F., E-mail: Ferran.Martin@uab.es

    2015-06-01

    This paper is focused on the analysis of transmission lines loaded with pairs of magnetically coupled resonators. We have considered two different structures: (i) a microstrip line loaded with pairs of stepped impedance resonators (SIRs), and (ii) a coplanar waveguide (CPW) transmission line loaded with pairs of split ring resonators (SRRs). In both cases, the line exhibits a single resonance frequency (transmission zero) if the resonators are identical (symmetric structure with regard to the line axis), and this resonance is different to the one of the line loaded with a single resonator due to inter-resonator coupling. If the structures are asymmetric, inter-resonator coupling enhances the distance between the two split resonance frequencies that arise. In spite that the considered lines and loading resonators are very different and are described by different lumped element equivalent circuit models, the phenomenology associated to the effects of coupling is exactly the same, and the resonance frequencies are given by identical expressions. The reported lumped element circuit models of both structures are validated by comparing the circuit simulations with extracted parameters with both electromagnetic simulations and experimental data. These structures can be useful for the implementation of microwave sensors based on symmetry properties. - Highlights: • Magnetic-coupling between resonant elements affects transmission properties. • Inter-resonant coupling enhances the distance of two resonant frequencies. • The structures are useful for sensors and comparators, etc.

  18. On-chip sub-terahertz surface plasmon polariton transmission lines in CMOS.

    Science.gov (United States)

    Liang, Yuan; Yu, Hao; Zhang, Hao Chi; Yang, Chang; Cui, Tie Jun

    2015-10-08

    A low-loss and low-crosstalk surface-wave transmission line (T-line) is demonstrated at sub-THz in CMOS. By introducing periodical sub-wavelength structures onto the metal transmission line, surface plasmon polaritons (SPP) are excited and propagate signals via a strongly localized surface wave. Two coupled SPP T-lines and two quasi-TEM T-lines are both fabricated on-chip, each with a separation distance of 2.4 μm using standard 65 nm CMOS technology. Measurement results show that the SPP T-lines achieve wideband reflection coefficient lower than -14 dB and crosstalk ratio better than -24 dB, which is 19 dB lower on average than the traditional T-lines from 220 GHz to 325 GHz. The demonstrated compact and wideband SPP T-lines have shown great potential for future realization of highly dense on-chip sub-THz communications in CMOS.

  19. Calculation Model for the Propagation of Audible Noise from High Voltage Transmission Lines

    Institute of Scientific and Technical Information of China (English)

    LI Xuebao; CUI Xiang; LU Tiebing; HE Jiamei

    2013-01-01

    Audible noise from high voltage transmission lines' corona discharge has become one of the decisive factors affecting design of high voltage transmission lines,thus it is very important to study the spatial propagation characteristics of audible noise for its accurate prediction.A calculation model for the propagation of audible noise is presented in this paper,which is based on the basic equation of the sound wave and can involve the influences of the atmosphere absorption and ground effects.The effects of different ground impedances and the atmospheric attenuation on the distribution of sound pressure level are discussed in this paper.The results show that the atmospheric absorption may increase the attenuation of the audible noise,and the ground surface affects both the amplitude and phase of the sound.The spatial distribution fluctuates considering the ground effects.The atmospheric attenuation and the ground effect are closely related to the frequency of the noise.In the frequency range of the audible noise,the influence of atmospheric attenuation on the spatial propagation characteristics is more obvious in high frequency while ground has significant influences in low frequency.

  20. A hybrid Boundary Element Unstructured Transmission-line (BEUT) method for accurate 2D electromagnetic simulation

    Science.gov (United States)

    Simmons, Daniel; Cools, Kristof; Sewell, Phillip

    2016-11-01

    Time domain electromagnetic simulation tools have the ability to model transient, wide-band applications, and non-linear problems. The Boundary Element Method (BEM) and the Transmission Line Modeling (TLM) method are both well established numerical techniques for simulating time-varying electromagnetic fields. The former surface based method can accurately describe outwardly radiating fields from piecewise uniform objects and efficiently deals with large domains filled with homogeneous media. The latter volume based method can describe inhomogeneous and non-linear media and has been proven to be unconditionally stable. Furthermore, the Unstructured TLM (UTLM) enables modelling of geometrically complex objects by using triangular meshes which removes staircasing and unnecessary extensions of the simulation domain. The hybridization of BEM and UTLM which is described in this paper is named the Boundary Element Unstructured Transmission-line (BEUT) method. It incorporates the advantages of both methods. The theory and derivation of the 2D BEUT method is described in this paper, along with any relevant implementation details. The method is corroborated by studying its correctness and efficiency compared to the traditional UTLM method when applied to complex problems such as the transmission through a system of Luneburg lenses and the modelling of antenna radomes for use in wireless communications.

  1. Inductive intrinsic localized modes in a one-dimensional nonlinear electric transmission line

    Science.gov (United States)

    Sato, M.; Mukaide, T.; Nakaguchi, T.; Sievers, A. J.

    2016-07-01

    The experimental properties of intrinsic localized modes (ILMs) have long been compared with theoretical dynamical lattice models that make use of nonlinear onsite and/or nearest-neighbor intersite potentials. Here it is shown for a one-dimensional lumped electrical transmission line that a nonlinear inductive component in an otherwise linear parallel capacitor lattice makes possible a new kind of ILM outside the plane wave spectrum. To simplify the analysis, the nonlinear inductive current equations are transformed to flux transmission line equations with analog onsite hard potential nonlinearities. Approximate analytic results compare favorably with those obtained from a driven damped lattice model and with eigenvalue simulations. For this mono-element lattice, ILMs above the top of the plane wave spectrum are the result. We find that the current ILM is spatially compressed relative to the corresponding flux ILM. Finally, this study makes the connection between the dynamics of mass and force constant defects in the harmonic lattice and ILMs in a strongly anharmonic lattice.

  2. Active Power Flow Optimization of Industrial Power Supply with Regard to the Transmission Line Conductor Heating

    Directory of Open Access Journals (Sweden)

    Leyzgold D.Yu.

    2015-04-01

    Full Text Available This article studies the problem of the transmission line conductor heating effect on the active power flows optimization in the local segment of industrial power supply. The purpose is to determine the optimal generation rating of the distributed power sources, in which the power flow values will correspond to the minimum active power losses in the power supply. The timeliness is the need to define the most appropriate rated power values of distributed sources which will be connected to current industrial power supply. Basing on the model of active power flow optimization, authors formulate the description of the nonlinear transportation problem considering the active power losses depending on the transmission line conductor heating. Authors proposed a new approach to the heating model parameters definition based on allowable current loads and nominal parameters of conductors as part of the optimization problem. Analysis of study results showed that, despite the relatively small active power losses reduction to the tune 0,45% due to accounting of the conductors heating effect for the present configuration of power supply, there are significant fluctuations in the required generation rating in nodes of the network to 9,32% within seasonal changes in the outer air temperature. This fact should be taken into account when selecting the optimum power of distributed generation systems, as exemplified by an arbitrary network configuration.

  3. Common raven occurrence in relation to energy transmission line corridors transiting human-altered sagebrush steppe

    Science.gov (United States)

    Coates, Peter S.; Howe, Kristy B.; Casazza, Michael L.; Delehanty, David J.

    2014-01-01

    Energy-related infrastructure and other human enterprises within sagebrush steppe of the American West often results in changes that promote common raven (Corvus corax; hereafter, raven) populations. Ravens, a generalist predator capable of behavioral innovation, present a threat to many species of conservation concern. We evaluate the effects of detailed features of an altered landscape on the probability of raven occurrence using extensive raven survey (n= 1045) and mapping data from southern Idaho, USA. We found nonlinear relationships between raven occurrence and distances to transmission lines, roads, and facilities. Most importantly, raven occurrence was greater with presence of transmission lines up to 2.2 km from the corridor.We further explain variation in raven occurrence along anthropogenic features based on the amount of non-native vegetation and cover type edge, such that ravens select fragmented sagebrush stands with patchy, exotic vegetative introgression. Raven occurrence also increased with greater length of edge formed by the contact of big sagebrush (Artemisia tridentate spp.) with non-native vegetation cover types. In consideration of increasing alteration of sagebrush steppe, these findings will be useful for planning energy transmission corridor placement and other management activities where conservation of sagebrush obligate species is a priority.

  4. Data-Mining-Based Intelligent Differential Relaying for Transmission Lines Including UPFC and Wind Farms.

    Science.gov (United States)

    Jena, Manas Kumar; Samantaray, Subhransu Ranjan

    2016-01-01

    This paper presents a data-mining-based intelligent differential relaying scheme for transmission lines, including flexible ac transmission system device, such as unified power flow controller (UPFC) and wind farms. Initially, the current and voltage signals are processed through extended Kalman filter phasor measurement unit for phasor estimation, and 21 potential features are computed at both ends of the line. Once the features are extracted at both ends, the corresponding differential features are derived. These differential features are fed to a data-mining model known as decision tree (DT) to provide the final relaying decision. The proposed technique has been extensively tested for single-circuit transmission line, including UPFC and wind farms with in-feed, double-circuit line with UPFC on one line and wind farm as one of the substations with wide variations in operating parameters. The test results obtained from simulation as well as in real-time digital simulator testing indicate that the DT-based intelligent differential relaying scheme is highly reliable and accurate with a response time of 2.25 cycles from the fault inception.

  5. Cryogenic Fiber Optic Sensors for Superconducting Magnets and Power Transmission Lines in High Energy Physics Applications

    CERN Document Server

    AUTHOR|(CDS)2081689; Bajko, Marta

    In the framework of the Luminosity upgrade of the Large Hadron Collider (HL - LHC), a remarkable R&D effort is now ongoing at the European Organization for Nuclear Research (CERN) in order to develop a new generation of accelerator magnets and superconducting power transmission lines. The magnet technology will be based on Nb3Sn enabling to operate in the 11 - 13 T range. In parallel, in order to preserve the power converters from the increasing radiation level, high power transmission lines are foreseen to feed the magnets from free - radiation zones. These will be based on high temperature superconductors cooled down with helium gas in the range 5 - 30 K. The new technologies will require advanced design and fabrication approaches as well as adapted instrumentation for monitoring both the R&D phase and operation. Resistive sensors have been used so far for voltage, temperature and strain monitoring but their integration still suffers from the number of electrical wires and the complex compensation o...

  6. Canby Area Service Project substation and associated transmission line. Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)

    1992-02-01

    Bonneville Power Administration (BPA) provides power to Surprise Valley Electrification Corporation (SVEC) in Modoc County, California. BPA uses PacificCorp`s substation and transmission facilities between Alturas and Canby, California to transfer power to SVEC`s Canby Substation. In the next year, SVEC expects increased industrial, agricultural, and residential electric loads on their 69-kV transmission system south of Canby. SVEC`s substation can accommodate only about 10 percent of the expected additional electric load. BPA`s proposed action is intended to meet SVEC`s increasing electric load. BPA proposes to meet SVEC`s increasing energy load by tapping into BPA`s existing BPA Malin-Warner 230-kV transmission line, and building an 7.9-mile transmission line to a new BPA substation. BPA proposes to build the new substation next to the west side of SVEC`s Canby Substation (Figure 1). This new substation will allow SVEC to move the additional power over their existing transmission or distribution lines. This report is the environmental assessment of the potential impact of the proposed project. The assessment determined that no ``environmental impact statement`` is not required.

  7. Dynamic simulation and experimental study of inspection robot for high-voltage transmission-line

    Institute of Scientific and Technical Information of China (English)

    XIAO Xiao-hui; WU Gong-ping; DU E; SHI Tie-lin

    2005-01-01

    A mobile robot developed by Wuhan University for full-path hotline inspection on 220 kV transmission lines was presented. With 4 rotating joints and 2 translational ones, such robot is capable of traveling along non-obstacle straight-line segment and surmounting straight-line segment obstacles as well as transferring between two spans automatically. Lagrange's equations were utilized to derive dynamic equations of all the links, including items of inertia, coupling inertia, Coriolis acceleration, centripetal acceleration and gravity. And a dynamic response experiment on elemental motions of robot prototype's travelling along non-obstacle straight-line segment and surmounting obstacles was performed on 220 kV 1∶1 simulative overhanging transmission-line in laboratory. In addition, dynamic numerical simulation was conducted in the corresponding condition. Comparison and analysis on results of experiment and numerical simulation have validated theoretical model and simulation resolution. Therefore, the dynamic model formed hereunder can be used for the study of robot control.

  8. Influence of Meteorological Parameters on Electromagnetic Environment of UHVDC Transmission Line Under High Altitude Condition

    Institute of Scientific and Technical Information of China (English)

    LIU Lei; LI Min; LI Ruihai; YU Zhanqing; LIUZhihong; LIU Xiangshi

    2012-01-01

    Measuring the electromagnetic (EM) environment parameters of a transmission line in bad weather conditions (such as rain, wind, etc. ) is difficult for technical staff. In the National Engineering Laboratory for UHV Technology (Kunming), a test line was completed for EM environment tests. An automated EM environment testing system was installed under the line, the rad{o interference (RI), audible noise (AN), resultant electric field strength (E0), and ion current density (Js) at ground level were measured under all weather conditions within a voltage range from ±800 kV to ± 1 000 kV over two years. Based on the measurement results, the influence of meteorological parameters on the EM environment of the transmission line was studied. When the HR increases from 40 % to 80%, the RI, AN, E0, Js would have different degrees of attenuation. The RI on a rainy day is 3 dB lower than that of a sunny day, while the Js gets a sharp increase with the same weather condition change. In addition, AN and E0 are greatly influenced by wind speed: with increasing wind speed, E0 decreases and AN becomes unstable.

  9. Voltage Stability of Long Transmission Line Equipped with a Thyristor Controlled Series Capacitor

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2012-01-01

    Full Text Available Problem statement: Power-Voltage curve provides very important information for voltage stability analysis. The exact long transmission line model consists of the resistance and the reactance. The resistance causes in the active line loss. It is not easy task to achieve the power-voltage curve characteristics of power system with the exact long line model equipeed with a Thyristor Controlled Series Capacitor (TCSC. Approach: This study applies the concept of the Newton-Raphson method to iteratively solve the nonlinear power flow equations. The Power-Voltage (P-V curve charateristic of the system without line loss and with line loss are plotted and compared on various cases. Results: It is found from the study that the resistance of the line obviously provides the negative effects on the voltage stability. The line loss causes in the decrement of the critical point. In addition, it is found that the leading power factor can increase the critical point of P-V curve. Conclusion: The exact long line model should be considered for voltage stability analysis of the system with the long transmission line.

  10. Voltage Stability of Medium Transmission Line Equipped with a Thyristor Controlled Series Capacitor

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2012-01-01

    Full Text Available Problem statement: Power-Voltage curve provides very important information for voltage stability analysis. The exact medium transmission line model consists of the resistance and the reactance. The resistance causes in the active line loss. It is not an easy task to achieve the power-voltage curve characteristics of power system with the exact medium line model equipped with a. Thyristor Controlled Series Capacitor (TCSC. Approach: This study applies the concept of the Newton-Raphson method to iteratively solve the nonlinear power flow equations. The Power-Voltage (P-V curve characteristic of the system without line loss and with line loss are plotted and compared with various cases. Results: It is found from the study that the resistance of the line obviously provides the negative effects on the voltage stability. The line loss causes in the decrement of the critical point. In addition, it is found that the leading power factor can increase the critical point of P-V curve. Conclusion: The exact medium line model should be considered for voltage stability analysis of the system with the medium transmission line.

  11. Power-Voltage Characteristics of Power System with the Long Transmission Line

    Directory of Open Access Journals (Sweden)

    Prechanon Kumkratug

    2012-01-01

    Full Text Available Problem statement: Power- Voltage curve provides very important information for voltage stability analysis. The exact long transmission line model consists of the resistance and the reactance. The resistance causes in the active line loss. It is not easy task to achieve the power-voltage curve characteristics of power system with the exact long line model. Approach: This study applies the concept of the Newton-Raphson method to iteratively solve the nonlinear power flow equations. The Power-Voltage (P-V curve characteristic of the system without line loss and with line loss are plotted and compared on various cases. Results: It is found from the study that the resistance of the line obviously provides the negative effects on the voltage stability. The line loss causes in the decrement of the critical point. In addition, it is found that the leading power factor can increase the critical point of P-V curve. Conclusion: The exact long line model should be considered for voltage stability analysis of the system with the long transmission line.

  12. Fiber Bragg Grating Sensor for Fault Detection in Radial and Network Transmission Lines

    Directory of Open Access Journals (Sweden)

    Mehdi Shadaram

    2010-10-01

    Full Text Available In this paper, a fiber optic based sensor capable of fault detection in both radial and network overhead transmission power line systems is investigated. Bragg wavelength shift is used to measure the fault current and detect fault in power systems. Magnetic fields generated by currents in the overhead transmission lines cause a strain in magnetostrictive material which is then detected by Fiber Bragg Grating (FBG. The Fiber Bragg interrogator senses the reflected FBG signals, and the Bragg wavelength shift is calculated and the signals are processed. A broadband light source in the control room scans the shift in the reflected signal. Any surge in the magnetic field relates to an increased fault current at a certain location. Also, fault location can be precisely defined with an artificial neural network (ANN algorithm. This algorithm can be easily coordinated with other protective devices. It is shown that the faults in the overhead transmission line cause a detectable wavelength shift on the reflected signal of FBG and can be used to detect and classify different kind of faults. The proposed method has been extensively tested by simulation and results confirm that the proposed scheme is able to detect different kinds of fault in both radial and network system.

  13. Component development for the ITER Ion Cyclotron Heating and Current Drive Transmission Line and Matching System

    Science.gov (United States)

    Goulding, R. H.; McCarthy, M. P.; Rasmussen, D. A.; Swain, D. W.; Barber, G. C.; Barbier, C. N.; Cambell, I. H.; Gray, S. L.; Moon, R. L.; Pesavento, P. V.; Sanabria, R. M.; Fredd, E.; Greenough, N.

    2013-10-01

    The transmission line and matching network for the ITER Ion Cyclotron Heating and Current Drive System feeds two equatorial launchers, each with 24 phased current straps combined into groups of three, and each designed to couple up to 20 MW into ELMy H-mode plasmas in the frequency range 40-55 MHz, for pulse lengths up to 3600 s. The network includes > 1 km of 50 Ohm 300 mm diameter transmission line carrying up to 6 MW net power per line at VSWR = 1.5. In addition, there are 8 power splitters, 32 hybrid phase shifters incorporating 64 tuning stubs, 32 additional tuning stubs, and 36 vacuum capacitors, which are configured to provide pre-matching in the port cell region adjacent to the antenna, final matching, decoupling of mutual inductances between antenna elements, and passive ELM resilience. The development and design of the various system components will be discussed. High power tests of components have begun, and the latest results will be presented. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.

  14. Mode Conversion Losses in Expansion Units for ITER ECH Transmission Lines

    Science.gov (United States)

    Schaub, S. C.; Shapiro, M. A.; Temkin, R. J.; Hanson, G. R.

    2016-01-01

    The ITER electron cyclotron heating transmission lines will consist of 63.5-mm-diameter corrugated waveguides, each carrying 1 MW of 170 GHz microwaves. These transmission lines must include expansion units to accommodate expansion and contraction along the path from the gyrotron microwave sources to the tokamak. A numerical mode matching code has been developed to calculate power losses due to mode conversion of the operating mode, HE11, to higher order modes as a result of the radial discontinuities in a sliding joint. Two expansion unit designs were evaluated, a simple gap expansion unit and a more complex tapered expansion unit. The gap expansion unit demonstrated loss that oscillated rapidly with expansion length, due to trapped modes within the unit. The tapered expansion unit has been shown to effectively suppress these trapped modes at the expense of increased fabrication complexity. In a gap expansion unit, for a waveguide step size of 2.5 mm, loss can be kept below 0.1 % to a maximum expansion length of 17 mm. Expansion units without corrugation on interior walls were also evaluated. Expansion units that lack corrugations are found to increase mode trapping within the units, though not beyond useful application. The mode matching code developed in this paper was also used to estimate mode conversion loss in vacuum pumpouts for the ECH lines; the estimated loss was found to be negligibly small.

  15. A transmission line model for propagation in elliptical core optical fibers

    Energy Technology Data Exchange (ETDEWEB)

    Georgantzos, E.; Boucouvalas, A. C. [Department of Telecommunications and Informatics, University of Peloponnese, Karaiskaki 70, 221 00, Tripoli Greece (Greece); Papageorgiou, C. [Department of Electrical Engineering, National technical University of Athens, Iroon Politechniou 9, Kaisariani, 16121, Athens (Greece)

    2015-12-31

    The calculation of mode propagation constants of elliptical core fibers has been the purpose of extended research leading to many notable methods, with the classic step index solution based on Mathieu functions. This paper seeks to derive a new innovative method for the determination of mode propagation constants in single mode fibers with elliptic core by modeling the elliptical fiber as a series of connected coupled transmission line elements. We develop a matrix formulation of the transmission line and the resonance of the circuits is used to calculate the mode propagation constants. The technique, used with success in the case of cylindrical fibers, is now being extended for the case of fibers with elliptical cross section. The advantage of this approach is that it is very well suited to be able to calculate the mode dispersion of arbitrary refractive index profile elliptical waveguides. The analysis begins with the deployment Maxwell’s equations adjusted for elliptical coordinates. Further algebraic analysis leads to a set of equations where we are faced with the appearance of harmonics. Taking into consideration predefined fixed number of harmonics simplifies the problem and enables the use of the resonant circuits approach. According to each case, programs have been created in Matlab, providing with a series of results (mode propagation constants) that are further compared with corresponding results from the ready known Mathieu functions method.

  16. Canby Area Service Project : Substation and Associated Transmission Line : Environmental Assessment.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1992-02-01

    Bonneville Power Administration (BPA) provides power to Surprise Valley Electrification Corporation (SVEC) in Modoc County, California. BPA uses PacificCorp's substation and transmission facilities between Alturas and Canby, California to transfer power to SVEC's Canby Substation. In the next year, SVEC expects increased industrial, agricultural, and residential electric loads on their 69-kV transmission system south of Canby. SVEC's substation can accommodate only about 10 percent of the expected additional electric load. BPA's proposed action is intended to meet SVEC's increasing electric load. BPA proposes to meet SVEC's increasing energy load by tapping into BPA's existing BPA Malin-Warner 230-kV transmission line, and building an 7.9-mile transmission line to a new BPA substation. BPA proposes to build the new substation next to the west side of SVEC's Canby Substation (Figure 1). This new substation will allow SVEC to move the additional power over their existing transmission or distribution lines. This report is the environmental assessment of the potential impact of the proposed project. The assessment determined that no environmental impact statement'' is not required.

  17. Experimental research on mechanical properties of high voltage transmission lines after the simulated wildfires

    Directory of Open Access Journals (Sweden)

    Wang Tianzheng

    2015-01-01

    Full Text Available In order to determine whether the mechanical performance after the fires of high voltage transmission lines meets the requirements of normal use, this article simulates the wildfire, and does the mechanical performance experiment of high voltage transmission lines(HVT lines after the simulated wildfires. The experiment studied the breaking force and elongation of each layer of 500kv HVT lines after the simulated wildfire. Experimental results show that, after fires, each layer of single aluminum wires of 500kv HVT lines have low breaking force which can be decreased obviously to half of that of new lines. For the steel core, decrease of breaking force is not obvious than aluminum wires, and with the increasing degree of wildfires, it increases gradually to a maximum of 35% of new steel lines’ breaking force. After wildfires, aluminum lines’ resistance ability of deformation decreases significantly, and its plastic deformation increases obviously during uniaxial tension. The steel core has little plastic deformation, and layers of aluminum become fluffy after fires. Therefore, the steel core main bearing load after wildfires.

  18. A novel structure of transmission line pulse transformer with mutually coupled windings.

    Science.gov (United States)

    Yu, Binxiong; Su, Jiancang; Li, Rui; Zhao, Liang; Zhang, Xibo; Wang, Junjie

    2014-03-01

    A novel structure of transmission line transformer (TLT) with mutually coupled windings is described in this paper. All transmission lines except the first stage of the transformer are wound on a common ferrite core for the TLT with this structure. A referral method was introduced to analyze the TLT with this structure, and an analytic expression of the step response was derived. It is shown that a TLT with this structure has a significantly slower droop rate than a TLT with other winding structures and the number of ferrite cores needed is largely reduced. A four-stage TLT with this structure was developed, whose input and output impedance were 4.2 Ω and 67.7 Ω, respectively. A frequency response test of the TLT was carried out. The test results showed that pulse response time of the TLT is several nanoseconds. The TLT described in this paper has the potential to be used as a rectangle pulse transformer with very fast response time.

  19. Power cables and transmission lines. A special issue; Kabels en lijnen. Special

    Energy Technology Data Exchange (ETDEWEB)

    Franken, B. [Vakgroep Electrische Energiesystemen, Technische Universiteit Eindhoven, Eindhoven (Netherlands); Hendriks Boers, M.H.A.J.; Bloemhof, G.A.; Pultrum, E.; Van der Wey, A.H.; Cremers, R. [KEMA Transport en Distributie, Arnhem (Netherlands); Rogier, J. [Dienst Methoden - Technische Assistentie, Departement Netten, Tractebel, Brussels (Belgium); Wiersma, J.A. [Regionale Energiemaatschappij Utrecht REMU, Utrecht (Netherlands); Birkhoelzer, W.A.; Lommen, P.P.C. [MEGA Limburg, Maastricht (Netherlands); Van Oirsouw, P. [KEMA Procesautomatisering en Informatietechnologie, Arnhem (Netherlands); Emous, K. [ed.

    1996-10-01

    In 8 articles several aspects with regard to cables and lines, applied in the electric power industry, are discussed. In the first article attention is paid to a new detection method for weak spots in cables. In the second article it is discussed that loading cables in a power distribution network more heavily has an impact on the reliability of the power supply. In article three the reliability of systems to protect the network against power failures is dealt with. The concept of a KEMA-developed computer program (PRORANK or Protection Reliability Analysis KEMA) is described and illustrated by two case studies. In article four the activities of CIGRE to realize a standard format for a database to maintaine and manage above-ground transmission lines are outlined. In article five the most important results and conclusions of a CIGRE working group on high-voltage cables and high-voltage lines are summarized. In the sixth article the developments with regard to discharge measurements for the diagnosis of cables are discussed, as well as the option of distributed optical measurement in high-voltage transmission cables. In article seven the so-called Power-Donut{sup TM} system is described by which the conductor temperature in high-voltage transmission lines can be determined. In the last article a KEMA-developed computer program (GAIA) for safety grounding analysis is discussed

  20. Growth and yield of winter wheat (Triticum aestivum L.) and corn (Zea mays L.) near a high voltage transmission line.

    Science.gov (United States)

    Soja, G; Kunsch, B; Gerzabek, M; Reichenauer, T; Soja, A-M; Rippar, G; Bolhàr-Nordenkampf, H R

    2003-02-01

    The objective of this study was to determine the effects of an electromagnetic field from a high voltage transmission line on the yield of agricultural crops cultivated underneath and near the transmission line. For 5 years, experiments with winter wheat and corn were carried out near the 380 kV transmission line Dürnrohr (Austria)-Slavetice (Czech Republic). Different field strengths were tested by planting the crops at different distances from the transmission line. The plants were grown in experimental plots (1.77 m2), aligned to equal electric field strengths, and were cultivated according to standard agricultural practice. The soil for all plots was homogenized layer-specifically to a depth of 0.5 m to guarantee uniform soil conditions in the plant root environment. The soil was sampled annually for determinations of carbon content and the behavior of microbial biomass. During development of the vegetation, samples were collected at regular intervals for growth rate analyses. At physiological maturity, the plots (n = 8) were harvested for grain and straw yield determinations. The average electric and magnetic field strengths at four distances from the transmission line (nominal distances: 40, 14, 8, and 2 m) were between 0.2 and 4.0 kV/m and between 0.4 and 4.5 micro T, respectively. No effect of the field exposures on soil microbial biomass could be detected. The wheat grain yields were 7% higher (average of 5 years) in the plots with the lowest field exposure than in the plots nearer to the transmission line (P plants were more pronounced in years with drought episodes during grain filling than in humid years. No significant yield differences were found for corn yields. The extent of the yield variations attributed to the distance from the transmission line was small compared to the observed annual variations in climatic or soil specific site characteristics. Copyright 2003 Wiley-Liss, Inc.

  1. Electrostatic trapping and in situ detection of Rydberg atoms above chip-based transmission lines

    Science.gov (United States)

    Lancuba, P.; Hogan, S. D.

    2016-04-01

    Beams of helium atoms in Rydberg-Stark states with principal quantum number n = 48 and electric dipole moments of 4600 D have been decelerated from a mean initial longitudinal speed of 2000 m s-1 to zero velocity in the laboratory-fixed frame-of-reference in the continuously moving electric traps of a transmission-line decelerator. In this process accelerations up to -1.3× {10}7 m s-2 were applied, and changes in kinetic energy of {{Δ }}{E}{kin}=1.3× {10}-20 J ({{Δ }}{E}{kin}/e=83 meV) per atom were achieved. Guided and decelerated atoms, and those confined in stationary electrostatic traps, were detected in situ by pulsed electric field ionisation. The results of numerical calculations of particle trajectories within the decelerator have been used to characterise the observed deceleration efficiencies, and aid in the interpretation of the experimental data.

  2. A Comparative Parametric Analysis of the Ground Fault Current Distribution on Overhead Transmission Lines

    Directory of Open Access Journals (Sweden)

    VINTAN, M.

    2016-02-01

    Full Text Available The ground fault current distribution in an effectively grounded power network is affected by various factors, such as: tower footing impedances, spans lengths, configuration and parameters of overhead ground wires and power conductors, soil resistivity etc. In this paper, we comparatively analyze, using different models, the ground fault current distribution in a single circuit transmission line with one ground wire. A parametric comparative analysis was done in order to study the effects of the non-uniformity of the towers footing impedances, number of power lines spans, soil resistivity, grounding systems resistances of the terminal substations etc., on the ground fault current distribution. There are presented some useful qualitative and quantitative results obtained through a complex dedicated developed MATLAB 7.0 program.

  3. A Suspended Stripline Frequency Tripler Using a Left-Handed Nonlinear Transmission Line

    Directory of Open Access Journals (Sweden)

    In Bok Kim

    2015-01-01

    Full Text Available A suspended stripline frequency tripler using a left-handed nonlinear transmission line (LH NLTL is presented. The proposed tripler using the LH NLTL is composed of a series of varactor diodes, shunt inductances, and a high-pass filter implemented with suspended stripline (SSL. An ultrawideband microstrip-to-suspended stripline transition is also utilized. The fabricated LH NLTL provides the minimum insertion loss of 1.7 dB and the maximum insertion loss of 4.7 dB for a wide frequency band from 2.6 to 18 GHz. As a tripler, the measured minimum third harmonic conversion loss is 15.3 dB at an input frequency of 2.4 GHz and typically 17 dB from 2 to 3.1 GHz.

  4. Adaptive Neurofuzzy Inference System-Based Pollution Severity Prediction of Polymeric Insulators in Power Transmission Lines

    Directory of Open Access Journals (Sweden)

    C. Muniraj

    2011-01-01

    Full Text Available This paper presents the prediction of pollution severity of the polymeric insulators used in power transmission lines using adaptive neurofuzzy inference system (ANFIS model. In this work, laboratory-based pollution performance tests were carried out on 11 kV silicone rubber polymeric insulator under AC voltage at different pollution levels with sodium chloride as a contaminant. Leakage current was measured during the laboratory tests. Time domain and frequency domain characteristics of leakage current, such as mean value, maximum value, standard deviation, and total harmonics distortion (THD, have been extracted, which jointly describe the pollution severity of the polymeric insulator surface. Leakage current characteristics are used as the inputs of ANFIS model. The pollution severity index “equivalent salt deposit density” (ESDD is used as the output of the proposed model. Results of the research can give sufficient prewarning time before pollution flashover and help in the condition based maintenance (CBM chart preparation.

  5. Regional analysis assessment of landslide hazard and zoning map for transmission line route selection using GIS

    Science.gov (United States)

    Baharuddin, I. N. Z.; Omar, R. C.; Usman, F.; Mejan, M. A.; Abd Halim, M. K.; Zainol, M. A.; Zulkarnain, M. S.

    2013-06-01

    The stability of ground as foundation for infrastructure development is always associated with geology and geomorphology aspects. Failure to carefully analyze these aspects may induce ground instability such subsidence and landslide which eventually can cause catastrophe to the infrastructure i.e. instability of transmission tower. However, in some cases such as the study area this is unavoidable. A GIS system for analysis of route was favoured to perform optimal route predictions based selection by incorporating multiple influence factors into its analysis by incorporating the Landslide Hazard Map (LHM) that was produced on basis of slope map, aspect map, land use map and geological map with the help of ArcGIS using weighted overlay method. Based on LHM it is safe to conclude that the proposed route for Ulu Jelai- Neggiri-Lebir-LILO transmission line has very low risk in term of landslides.

  6. Numerical Calculation of Transient Thermal Characteristics in Gas-Insulated Transmission Lines

    Directory of Open Access Journals (Sweden)

    Hongtao Li

    2013-11-01

    Full Text Available For further knowledge of the thermal characteristics in gas-insulated transmission lines (GILs installed above ground, a finite-element model coupling fluid field and thermal field is established, in which the corresponding assumptions and boundary conditions are given.  Transient temperature rise processes of the GIL under the conditions of variable ambient temperature, wind velocity and solar radiation are respectively investigated. Equivalent surface convective heat transfer coefficient and heat flux boundary conditions are updated in the analysis process. Unlike the traditional finite element methods (FEM, the variability of the thermal properties with temperature is considered. The calculation results are validated by the tests results reported in the literature. The conclusion provides method and theory basis for the knowledge of transient temperature rise characteristics of GILs in open environment.

  7. Thermal Analysis in Gas Insulated Transmission Lines Using an Improved Finite-Element Model

    Directory of Open Access Journals (Sweden)

    Ling LI

    2013-01-01

    Full Text Available  In this paper, an improved finite element (FE model is proposed to investigate the temperature distribution in gas insulated transmission lines (GILs. The solution of joule losses in eddy current field analysis is indirectly coupled into fluid and thermal fields. As is different from the traditional methods, the surrounding air of the GIL is involved in the model to avoid constant convective heat transfer coefficient, thus multiple species transport technique is employed to deal with the problem of two fluid types in a single model. In addition, the temperature dependent electrical and thermal properties of the materials are considered. The steady-state and transient thermal analysis of the GIL are performed separately with the improved model. The corresponding temperature distributions are compared with experimental results reported in the literature.

  8. Multiband Slot-Based Dual Composite Right/Left-Handed Transmission Line

    Directory of Open Access Journals (Sweden)

    E. Abdo-Sanchez

    2012-10-01

    Full Text Available A dual Composite Right-/Left-Handed Transmission Line (CRLH TL implementation that presents multiband behaviour is proposed in this contribution. The artificial TL is realized by loading a host microstrip line with alternate rectangular stubs and slots. The required series and shunt immittances are respectively provided by the slot and the stub. Due to the distributed nature of these immittances, the resultant phase response presents theoretically infinite RH and LH alternate bands, thus being appropriate for multiband applications. The design methodology is described with the help of a proposed TLs-based equivalent circuit and highlights the simplicity for balance condition. Full wave simulated results of the dispersion characteristics and frequency response of a unit-cell and a three-cells structure are presented.

  9. Evaluating the CDM-Robustness of the input buffer with very fast transmission line pulse

    Science.gov (United States)

    Kao, Tzu-Cheng; Lee, Jian-Hsing; Hung, Chung-Yu; Lien, Chen-Hsin; Su, Hung-Der

    2015-02-01

    In this paper, a scheme for how to utilize VFTLP (very fast transmission line pulse) data to design an input buffer circuit for CDM (charged-device model) ESD protection is reported. The impedance of the ESD device under VFTLP stress is nearly 120 Ω at the beginning of turn-on transient, and decreases with time toward 10 Ω prior to the voltage falling below 0 V. In this work, the fact that the dynamic-characteristic impedance of the ESD device under VFTLP testing is independent of the stress current is found. Since both VFTLP zapping and the CDM are nanosecond events, the dynamic-characteristic impedance of the ESD device can be used to evaluate the CDM threshold voltage of the input buffer based on the equivalent and simplified RLC circuit.

  10. A summary of the results of the CEA transmission line performance survey

    Energy Technology Data Exchange (ETDEWEB)

    Gelineau, P. [Canadian Electricity Association, Montreal, PQ (Canada)

    2006-07-01

    In an effort to gather information on forced power outages, the Canadian Electricity Association conducted a survey using its Equipment Reliability Information System (ERIS). The survey covered elements such as transmission equipment reliability in terms of transmission lines, cables, transformer banks, circuit breakers, synchronous compensators, static compensators, shunt reactor banks, shunt capacitor banks, and series capacitor banks. The survey provided details regarding the cause of failure, design information, and an in-depth analysis of statistics regarding the number of outages, frequency, total time, mean duration, median duration, and availability. The survey revealed that the primary causes of outages were defective equipment, adverse weather, adverse environment, system conditions, human error, and foreign interference. tabs., figs.

  11. Semi-flexible gas-insulated transmission line using sandwiched discs for intermittent flexing joints

    Energy Technology Data Exchange (ETDEWEB)

    Kommineni, Prasad R. (Westboro, MA)

    1983-02-15

    A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by the use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements are formed by sandwiching together, by fusing, a pair of thin hollow discs which are fixedly secured to both the main conductor sections and the conductor hub section.

  12. Semi-flexible gas-insulated transmission line using sandwiched discs for intermittent flexing joints

    Energy Technology Data Exchange (ETDEWEB)

    Kommineni, P.R.

    1983-02-15

    A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by the use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements are formed by sandwiching together, by fusing, a pair of thin hollow discs which are fixedly secured to both the main conductor sections and the conductor hub section. 4 figs.

  13. Experimental research on Ku-band magnetically insulated transmission line oscillator

    Science.gov (United States)

    Jiang, Tao; Zhang, Jiande; He, Juntao; Li, Zhiqiang; Ling, Junpu

    2015-10-01

    An improved Ku-band magnetically insulated transmission line oscillator is proposed and investigated experimentally. In the particle-in-cell simulation, the Ku-band MILO generates the microwave with a power of 1.62 GW and a frequency of 13 GHz at the input voltage of 474 kV. The device is fabricated based on the simulation results, and an experiment system is designed. In the preliminary experiments, output microwave with frequency of 13.02 GHz, power of 150 MW, and pulse width of 17 ns is generated, under the diode voltage of 450 kV. Analysis on the experiment results shows that plasma produced due to the large current hitting to the outside of the collection tank is the essential cause for the low amplitude of the microwave power and short pulse width.

  14. Performance evaluation of a lossy transmission lines based diode detector at cryogenic temperature

    Science.gov (United States)

    Villa, E.; Aja, B.; de la Fuente, L.; Artal, E.

    2016-01-01

    This work is focused on the design, fabrication, and performance analysis of a square-law Schottky diode detector based on lossy transmission lines working under cryogenic temperature (15 K). The design analysis of a microwave detector, based on a planar gallium-arsenide low effective Schottky barrier height diode, is reported, which is aimed for achieving large input return loss as well as flat sensitivity versus frequency. The designed circuit demonstrates good sensitivity, as well as a good return loss in a wide bandwidth at Ka-band, at both room (300 K) and cryogenic (15 K) temperatures. A good sensitivity of 1000 mV/mW and input return loss better than 12 dB have been achieved when it works as a zero-bias Schottky diode detector at room temperature, increasing the sensitivity up to a minimum of 2200 mV/mW, with the need of a DC bias current, at cryogenic temperature.

  15. Modeling and Simulation Analysis of Power Frequency Electric Field of UHV AC Transmission Line

    Directory of Open Access Journals (Sweden)

    Chen Han

    2015-02-01

    Full Text Available In order to study the power frequency electric field of UHV AC transmission lines, this paper which models and calculates using boundary element method simulates various factors influencing the distribution of the power frequency electric field, such as the conductor arrangement, the over-ground height, the split spacing and the sub conductor radius. Different influence of various factors on the electric field distribution will be presented. In a single loop, using VVV triangular arrangement is the most secure way; in a dual loop, the electric field intensity using reverse phase sequence is weaker than that using positive phase sequence. Elevating the over-ground height and reducing the conductor split spacing will both weaken the electric field intensity, while the change of sub conductor radius can hardly cause any difference. These conclusions are important for electric power company to detect circuit.

  16. Gain compensated symmetric loaded transmission line exhibiting bidirectional negative group delay

    Science.gov (United States)

    Bridges, Greg E.; Kandic, Miodrag

    2012-12-01

    A one-dimensional medium capable of bidirectional lossless negative group delay electromagnetic wave propagation is described. The medium is implemented as a microwave circuit comprising two symmetric resonator-loaded transmission lines, with active gain compensation and coupled through power combiners. We experimentally demonstrate the circuit is conditionally stable and is capable of lossless transmission of a finite bandwidth pulse in both directions. A measured group delay of -600 ps with a gain of 1.12 dB in both directions is achieved for a Gaussian pulse with a bandwidth of 14 MHz modulated at a frequency of 280 MHz (NGD-bandwidth-product of 0.0084). This circuit demonstrates the possibility of constructing a one-dimensional spatial void.

  17. Extension of Pierce model to multiple transmission lines interacting with an electron beam

    CERN Document Server

    Tamma, Venkata Ananth

    2013-01-01

    A possible route towards achieving high power microwave devices is through the use of novel slow-wave structures employing multiple coupled transmission lines (MTLs) whose behavior when coupled to electron beams have not been sufficiently explored. We present the extension of the one-dimensional linearized Pierce theory to MTLs coupled to a single electron beam. We develop multiple formalisms to calculate the k-{\\omega} dispersion relation of the system and find that the existence of a growing wave solution is always guaranteed if the electron propagation constant is larger than or equal to the largest propagation constant of the MTL system. We verify our findings with illustrative examples which bring to light unique properties of the system in which growing waves were found to exist within finite bands of the electron propagation constant and discuss possible approach to improve the gain. By treating the beam-MTL interaction as distributed dependent current generators in the MTL, we derive relations charact...

  18. Accurate fault location algorithm on power transmission lines with use of two-end unsynchronized measurements

    Directory of Open Access Journals (Sweden)

    Mohamed Dine

    2012-01-01

    Full Text Available This paper presents a new approach to fault location on power transmission lines. This approach uses two-end unsynchronised measurements of the line and benefits from the advantages of digital technology and numerical relaying, which are available today and can easily be applied for off-line analysis. The approach is to modify the apparent impedance method using a very simple first-order formula. The new method is independent of fault resistance, source impedances and pre-fault currents. In addition, the data volume communicated between relays is sufficiently small enough to be transmitted easily using a digital protection channel. The proposed approach is tested via digital simulation using MATLand the applied test results corroborate the superior performance of the proposed approach.

  19. Electrostatic trapping and in situ detection of Rydberg atoms above chip-based transmission lines

    CERN Document Server

    Lancuba, P

    2016-01-01

    Beams of helium atoms in Rydberg-Stark states with principal quantum number $n=48$ and electric dipole moments of 4600~D have been decelerated from a mean initial longitudinal speed of 2000~m/s to zero velocity in the laboratory-fixed frame-of-reference in the continuously moving electric traps of a transmission-line decelerator. In this process accelerations up to $-1.3\\times10^{7}$~m/s$^2$ were applied, and changes in kinetic energy of $\\Delta E_{\\mathrm{kin}}=1.3\\times10^{-20}$~J ($\\Delta E_{\\mathrm{kin}}/e = 83$~meV) per atom were achieved. Guided and decelerated atoms, and those confined in stationary electrostatic traps, were detected in situ by pulsed electric field ionisation. The results of numerical calculations of particle trajectories within the decelerator have been used to characterise the observed deceleration efficiencies, and aid in the interpretation of the experimental data.

  20. Scalable wideband equivalent circuit model for silicon-based on-chip transmission lines

    Science.gov (United States)

    Wang, Hansheng; He, Weiliang; Zhang, Minghui; Tanh, Lu

    2017-06-01

    A scalable wideband equivalent circuit model of silicon-based on-chip transmission lines is presented in this paper along with an efficient analytical parameter extraction method based on improved characteristic function approach, including a relevant equation to reduce the deviation caused by approximation. The model consists of both series and shunt lumped elements and accounts for high-order parasitic effects. The equivalent circuit model is derived and verified to recover the frequency-dependent parameters at a range from direct current to 50 GHz accurately. The scalability of the model is proved by comparing simulated and measured scattering parameters with the method of cascade, attaining excellent results based on samples made from CMOS 0.13 and 0.18 μm process. Project supported by National Natural Science Foundation of China (No. 61674036).