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Dielectrics and Electrical Insulation, IEEE Transactions on

Issue 6 • Date Dec. 2001

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Displaying Results 1 - 25 of 37
  • A self-organizing fuzzy inference system for electric field optimization of HV electrode systems

    Publication Year: 2001 , Page(s): 995 - 1002
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (748 KB) |  | HTML iconHTML  

    Development of efficient methods for optimum design of electrode and insulator contour in a HV apparatus has been an important area of research in the recent past. A self-organizing fuzzy inference system is developed for electrode optimization which is an improved version over traditional iterative approach of optimization and more recent methods employing neural networks. This fuzzy system has been implemented for two practical examples of an axisymmetric single-phase gas-insulated system (GIS) bus termination and a disconnecter switch configuration. Improved electric stress distribution demonstrates the usefulness of the proposed method. A new methodology for automatic generation of the fuzzy rule base from the input-output data set is also proposed in this scheme. This fuzzy system is much simpler and less time consuming to implement compared to other optimization techniques presently available for optimization of HV electrodes. View full abstract»

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  • Author index

    Publication Year: 2001 , Page(s): 1116 - 1126
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    Freely Available from IEEE
  • Subject index

    Publication Year: 2001 , Page(s): 1127 - 1146
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    Freely Available from IEEE
  • Applying a gas mixture containing c-C4F8 as an insulation medium

    Publication Year: 2001 , Page(s): 1075 - 1081
    Cited by:  Papers (18)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (483 KB) |  | HTML iconHTML  

    This paper studies the possibility of applying a gas mixture containing c-C4F8 in the gas insulation of power equipment. Environmental aspects such as global warming potential, ozone depletion potential, recycling loss and toxicity are discussed. Insulation characteristics of gas mixtures such as c-C4F8/N2, c-C4F8/air, and c-C4F8/CO 2 are examined experimentally under a quasi-homogeneous or an inhomogeneous electric field condition. Most of the characteristics are compared with those of SF6/N2, which is now widely studied as the most plausible alternative to pure SF6 for gas insulation. The experimental results, together with the discussion, suggest that gas mixtures containing c-C4F8 are possible substitutes for SF6 and SF6/N2 View full abstract»

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  • Epilogue

    Publication Year: 2001 , Page(s): 857 - 858
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    First Page of the Article
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  • Edge breakdown issues in field emission displays

    Publication Year: 2001 , Page(s): 1025 - 1028
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (362 KB) |  | HTML iconHTML  

    This paper addresses edge breakdown issues in vacuum gap structures similar to field emission displays, both from a theoretical and practical point of view. Several unique solutions have been developed. After using these technologies, the breakdown voltage of a 750 μm plain-vacuum gap formed by two thin-film electrodes was improved from ~16 to ~24 kV for the first run, and ~20 to 28 kV for the conditioned regime. The mechanism of breakdown in a plain vacuum gap is discussed View full abstract»

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  • Fundamental investigations on some transformer liquids under various outdoor conditions

    Publication Year: 2001 , Page(s): 1040 - 1047
    Cited by:  Papers (15)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (730 KB) |  | HTML iconHTML  

    This paper deals with humidity uptake of some transformer liquids and its influence on electrical breakdown. The investigations were performed under some selective outdoor conditions on different insulating liquids, e.g. mineral oil, esters and silicones used in HV transformers. The temperature was set at 23 or 60 °C while the relative air humidity was varied between 20 and 90% to simulate climatic variation. The subject is important in HV transformers with an air breathing system since, even in such transformers where normally the air passes through a dehydrating apparatus with silica gel, a bad run can induce an accident. The scenario considered corresponds to such a defect in the breathing filter system, so that the insulating liquid in the transformer comes into contact with atmospheric humidity. The work presented is in two parts. The first part relates the evolution of the breakdown voltage in terms of the insulating liquid humidity content. The second part describes the evolution of insulating liquid humidity content in terms of surrounding relative air humidity. This evolution is observed during 30 days and the results are discussed regarding the ac electric strength according to International Electrotechnical Commission (IEC) or Verband der Elektrotechnik Elektronik Informationstechnik e.V. (VDE) standards. A correlation between the surrounding relative air humidity, temperature and humidity uptake rate is derived View full abstract»

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  • Dielectric studies of PVDF crystallization. Application to in-situ monitoring in injection molding

    Publication Year: 2001 , Page(s): 911 - 916
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (596 KB) |  | HTML iconHTML  

    In recent years, experimental techniques based on microdielectrometry have presented an attractive and increasing interest for continuous monitoring in a nondestructive way of the advancement of thermoset resin reactions under cure. A new application of this technique has been carried out also for in situ monitoring of thermoplastic crystallization. Therefore, a dynamic rheometer equipped with a dielectric cell, as well as an instrumented slit die, were designed. The crystallization process is depicted by a conductivity drop as well as by the occurrence of a maximum in the real permittivity. The decrease of the specific conductivity results from a modification of the conductive paths whereas the increase in permittivity is due to an interfacial polarization phenomenon between the amorphous phase and the growing crystalline entities. As a second step of development, microdielectrometry has been applied for in situ monitoring of the crystallization of thermoplastics during an injection molding process. The electric sensors were located at the walls of the mold cavity so that an analysis of bulk dielectric properties during the filling, post-filling and the cooling phases could be performed. The dielectric method detailed herein provides a new non-invasive technique and could be applied to a closed-loop control of the injection molding process View full abstract»

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  • Study of space charge accumulation in polyolefins submitted to ac stress

    Publication Year: 2001 , Page(s): 972 - 984
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1205 KB) |  | HTML iconHTML  

    The aim of the present study was to follow space charge formation under ac field (50 Hz) in polyolefins. The thermal step method was used, and charge accumulation was observed in crosslinked polyethylene (XLPE), very low density polyethylene (VLDPE), isotactic polypropylene (PP) and a PE /PP copolymer, the temperature varying from 45 to 90°C. It was found that the amount of charge accumulated under ac conditions may reach a maximum value at a given temperature, while the highest space charge was found in the polyolefin with the lowest crystallinity ratio. The conduction current characteristics of XLPE specimens show the existence of traps in the polymer at a level deeper than the potential barrier electrode/dielectric, explaining the accumulation of injected charge in the material. The injection and conduction mechanisms observed were interpreted by Schottky and Poole-Frenkel processes and used to explain the maximum accumulation of charge occurring at certain temperatures View full abstract»

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  • Charge carrier trapping in a one-dimensional system

    Publication Year: 2001 , Page(s): 1007 - 1010
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (293 KB) |  | HTML iconHTML  

    Theoretical models for one-dimensional structures, consisting of traps and recombination centers, are considered. The kinetics of trapping and recombination is studied numerically, especially in the case of thermal relaxation phenomena such as thermoluminescence (TL) and thermally stimulated current (TSC). Some peculiarities of TL and TSC are shown, which result from specific spatial arrangement of traps. The possibility of occurrence of an additional 'displacement' peak on TL and TSC measurement curves is predicted. Possible consequences for experimental studies of TL and TSC are discussed View full abstract»

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  • Influence of frequency on water tree growth in various test cells

    Publication Year: 2001 , Page(s): 1082 - 1087
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (500 KB) |  | HTML iconHTML  

    It is well known that water treeing in polyethylene (PE) is sensitive to frequency, but there is not yet a reliable analytic model describing this empirical observation. We show from existing published data that the length L of water trees grown in the laboratory under one given ionic solution varies linearly when plotted as log L vs. log N1 where N is the number of field cycles. This relation is nearly independent of the applied field, suggesting a fatigue-like process. Ion concentration has only a slight influence on watertree length, especially after long aging. It was observed also that field aging and thermal aging reduce the watertree length. Some authors have suggested that there is an upper frequency limit above which water treeing would be independent of frequency. We have observed that the relationship log L vs. log N deviates from its linear behavior between 30 and 445 kHz. More work is needed to define more precisely the upper frequency limit. This means that accelerated aging for watertree degradation could be done at high frequency and results could then be translated reliably to power frequency. Finally, the fact that all experimental data obtained with one given ion obey the same relation regardless of types of the test cells indicates that results obtained with one given cell can be compared directly to those obtained with any other cell. Practical considerations also are discussed briefly View full abstract»

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  • Elemental strain and trapped space charge in thermoelectrical aging of insulating materials. Part 1: Elemental strain under thermo-electrical-mechanical stress

    Publication Year: 2001 , Page(s): 959 - 965
    Cited by:  Papers (17)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (665 KB) |  | HTML iconHTML  

    The life model proposed previously by the authors ascribes electrothermal aging to the formation and/or enlargement of nanovoids driven by electromechanical energy stored in local concentrations of space charge. In the previous work, the strain associated with the mechanical stress produced by the space charge center was derived using a macroscopic stress-strain relationship. For chain conformation changes on the molecular scale, these macroscopic concepts may no longer be valid. In this paper, we have investigated the possibility that the local strain is an elemental property of the polymer morphology, as suggested by molecular quantum mechanical calculations. The elemental strain has been related to the bulk modulus through the elemental volume of the affected chain section and the number density of contributing centers. In this way an upper bound has been obtained for the elemental strain as a function of these variables. Under the assumption that the charge concentrations are formed by charges trapped in nanovoids, estimates have been obtained for the smallest magnitude of the local field that is able to initiate aging, and these estimates have been correlated with the maximum number of electronic charges that such a void may trap. By doing so, a connection is found between the aging model and experimental space charge densities. This connection is the subject of Part 2 of this paper View full abstract»

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  • Diagnostic dielectric spectroscopy methods applied to water-treed cable

    Publication Year: 2001 , Page(s): 917 - 920
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (282 KB) |  | HTML iconHTML  

    Considerable effort has gone into developing polymer formulations and cable designs to minimize failures through water tree growth. However, diagnostic techniques still are required to enable the estimation of the level of damage present within a service cable. This paper reports on progress regarding the application of dielectric spectroscopy to cable diagnostics. A 40 kV, crosslinked polyethylene (XLPE) insulated coaxial cable was used as a model power cable. Sample lengths were immersed in a potassium chloride solution and some of these were subjected to AC electrical stress. After an 8 week duration, a high density of tress was found in the electrically stressed cable. Dielectric spectra have been measured for both sample types in the frequency range of 10-5 to 105 Hz. Insertion loss measurements were also carried out in the frequency range of 3×10 5 to 3×109 Hz. From both types of measurement, it was possible to distinguish between the cables containing water trees and those that were free from water tree structures. These approaches could therefore be developed in order to provide diagnostics for the detection of water tree damage in electrical power cables View full abstract»

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  • Electrical characterization of SiOx and SiNx prepared by PECVD technique on In0.53Ga0.47As

    Publication Year: 2001 , Page(s): 1011 - 1015
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    We have analyzed the electrical properties of both SiOx on InGaAs and SiNx on InGaAs, by utilizing a metal-insulator-semiconductor (MIS) structure. For improving film or interface quality, both oxide and nitride samples underwent furnace annealing (FA) in hydrogen at various temperatures. From the leakage current and capacitance characterization, we found that the electrical properties of the nitride samples such as leakage current, injected charges, and interface trap density are improved by FA, while on the contrary, the properties of the oxide samples are slightly deteriorated. The optimum annealing temperature for nitride samples is in the temperature range of ~400 to 450°C. Also, by secondary ion mass spectroscopy (SIMS) analysis, we provide evidence of inter-diffusion occurring in the oxide samples after annealing View full abstract»

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  • SEM-mirror methods and application to insulator characterization

    Publication Year: 2001 , Page(s): 942 - 952
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1184 KB) |  | HTML iconHTML  

    The SEM mirror method (SEMM) is a nondestructive technique developed for insulators characterization. It provides measurements on the charge trapping ability under high electric field with a spatial resolution down to 1 μm. SEMM consists of experimental measurements, ground current and minor plot, and a simulation part using Monte Carlo calculations. The mirror plot gives information on the trapped charge distribution at an equilibrium state. Many experimental results on different kind of materials, e.g. polymers, ceramics, single crystals, have shown that the mirror plot is useful to study insulators properties. But, the charge distribution deduced from the experimental minor plot is not unique and more information about charge buildup is needed to reduce the set of solutions. More recently, the ground current measurement during the injection phase gave complementary results on the charge trapping rate. Under specific conditions, peaks of electron emission occur during injection which have been associated with a local flashover. This result clearly shows that SEMM is able to study insulators under high field stress close to the breakdown strength. To understand the mirror experiments, a more complete simulation of the injection phase is needed. This can be achieved through Monte Carlo simulation of the electron-matter interactions by taking into account charge trapping and detrapping processes under high field. Using these three complementary approaches, it is possible to get a better understanding of charge trapping and detrapping processes in insulators under high electric field with a fine spatial resolution View full abstract»

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  • Discharge energy and dc tracking resistance of organic insulating materials

    Publication Year: 2001 , Page(s): 897 - 901
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (390 KB) |  | HTML iconHTML  

    As an evaluation test method for surface insulation degradation of organic insulating materials, the tracking test method is described in IEC Publ.112 as a safe and reliable evaluation. This publication has now been applied to the material selection. Due to the fact that the experimental values of the comparative tracking index (CTI), have wide variations, problems in reliability testing are abundant. In this paper, the correlation is investigated between discharge energy and tracking resistance of organic insulating materials. The test method resembles the IEC Publ.112 method, but with the application of dc voltages. The number of drops to tracking failure was measured with samples of paper based phenolic laminate, polybutylene terephthalate and epoxy resin. Discharge currents were detected when discharge occurred on the sample surface. A Gaussian wavelet analysis was applied to show energy levels of discharge currents. It was found that the tendency of discharge energy on organic insulating materials corresponded to the CTI of dc tracking resistance, and the results were an improvement on the IEC Publ.112 method for grading materials. The tracking resistance of organic insulating materials could be deduced from the discharge energy View full abstract»

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  • Comparison of dielectric properties determined from a computational approach and experiment for anisotropic and periodic heterostructures

    Publication Year: 2001 , Page(s): 921 - 929
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (817 KB) |  | HTML iconHTML  

    The physics of heterostructures is among the forefront problems in materials science. Composite materials also are attractive from the point of view of technological applications such as current-limiting thermistors, radar absorbers, and electromagnetic shields, because they exhibit a variety of interesting mechanical, electric and magnetic properties with the advantage of much reduced cost and weight. To quantify the dielectric response of anisotropic and periodic heterostructures, consisting of two-component composites arranged in a regular simple cubic lattice, in the quasistatic approximation we use an exact numerical technique which is based on a boundary integral equations solution of the Laplace equation which is solved by using the field calculation package PHI3D. 'Exact' means that the correct properties are computed for the given microstructure and choice of individual component properties because all internal electric multipole interactions contributing to the polarization of the material medium are taken into account. The main goal of this work was to confront these numerical calculations with experimental data. Measurements of the effective complex permittivity were carried out in samples composed of identical aligned inclusions, in the form of circular cylinders, embedded in a polymer matrix and filled either by de-ionized water or air. We test our numerical data for two specific examples, i.e. the parallel and perpendicular orientation of the electric field vector with respect to the principal axis of the circular cylinders. Of particular importance is that our numerical simulation captures reasonably well the observed trend in the experimental data over a wide range of volume fraction of inclusions. The experimental results roughly indicate a significant decrease in the permittivity in the x-y plane over that of the z axis, for inclusions containing de-ionized water, while no anisotropy effect is found for inclusions With air. However, there are quantitative differences between the experiment and calculations. These differences were tentatively ascribed to limitations in the experimental model, i.e. finite size, and air bubbles due to ill-controlled filling of the cylindrical inclusions View full abstract»

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  • Thermal step method for space charge measurements under applied dc field

    Publication Year: 2001 , Page(s): 985 - 994
    Cited by:  Papers (14)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (856 KB) |  | HTML iconHTML  

    The thermal step method (TSM) is a nondestructive technique which measures the distribution of the electric field and space charge density across solid insulating materials. This work first reviews the principle and the basic equations of the TSM when used on a short circuited flat insulating structure (film or plate). An evolution of the method, which allows the determination of space charge distribution in an insulator while submitted to an external dc field, is then described. The fundamentals, the experimental setup and the validation of this technique on flat samples and on power cables are presented and discussed View full abstract»

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  • Loss and recovery of hydrophobicity and surface energy of HTV silicone rubber

    Publication Year: 2001 , Page(s): 1088 - 1097
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (867 KB) |  | HTML iconHTML  

    The loss of surface hydrophobicity of high temperature vulcanized (HTV) silicone rubber (SIR) due to immersion in saline solutions (0.005 to 100 mS/cm) has been studied as a function of immersion time (0 to 576 h) and temperature (0 to 98°C). The subsequent recovery of the hydrophobicity in air is determined also. The loss and recovery of the hydrophobicity is correlated with the absorption of water during immersion and its subsequent desorption in air. The hydrophobicity is determined by measuring the static contact angle θ between the tangent to a droplet of distilled water and the horizontal HTV-SIR surface. The surface energies γS, γSD and γSH of HTV-SIR, the energy of adhesion WSL and the surface tension γSL of water to HTV-SIR were determined as a function of time of immersion (loss of hydrophobicity), the time of recovery of hydrophobicity and the contact angle of water. For virgin HTV-SIR at 24.5±3.5°C the surface energies were determined to be γS=31.6 mJ/m2, γSD=28.5 mJ/m2, γ SH=3.1 mJ/m2, WSL=61.4 mJ/m2 and γSL=43.0 J/m2. These values are in reasonable agreement with the literature View full abstract»

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  • Streamer/leaders from a metallic particle between parallel plane electrodes in transformer oil

    Publication Year: 2001 , Page(s): 1054 - 1063
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1112 KB) |  | HTML iconHTML  

    Prebreakdown channels initiated at, and propagating from, an electrically floating wire particle located between two parallel electrodes under impulse voltage have been studied. The propagation characteristics do to some degree resemble what has been found in point to plane gaps. Channels will, when they meet a barrier or an electrode covering perpendicular to the field, stop and spread out on the surface leaving charge that may form Lichtenberg figures. Charge measurements and registration of the size of Lichtenberg figures do support a capacitance based model of the propagation View full abstract»

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  • Particles in GIS characterization from acoustic signatures

    Publication Year: 2001 , Page(s): 1064 - 1074
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (925 KB) |  | HTML iconHTML  

    Acoustic techniques are accepted generally for diagnostics of gas-insulated systems (GIS). This paper addresses the problem of risk assessment of moving particles. The main part of the paper gives a general understanding of internal particle movement and excitation of external acoustic signals, leading to signature analysis and simple calculation of characteristics such as mass and length of the particle, and its elevation height in a GIS duct. This is supported by experimental studies of acoustic and electric signals from moving particles. It is shown how partial discharge (PD) at a particle reduces the jumping tendency, and how discharges with time will change when the shape of the particle changes. Experiments on sensor sensitivity and on the coefficient of restitution also have been carried out. The signature analysis and given formulas constitute a good tool for discriminating between harmless and harmful particles, as well as offering a tool for better understanding the particle movement View full abstract»

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  • Elemental strain and trapped space charge in thermoelectrical aging of insulating materials: life modeling

    Publication Year: 2001 , Page(s): 966 - 971
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (462 KB) |  | HTML iconHTML  

    On the basis of the new concept of elemental strain, used to describe a possible aging process occurring in polymeric materials, the expression for the life model, already proposed in a previous paper, must be modified, taking into account the possibility that the local strain is an elemental property of the polymer morphology, as suggested by molecular quantum calculations. By doing so, a connection can be established between the life model and space charge densities as revealed by experiments. The derivation of this new model and the correlation with analytical measurements is the subject of this paper. Applying this connection to electrical aging and space charge data for the same crosslinked polyethylene (XLPE) material has resulted in a set of material factors that we have demonstrated are both consistent with experiments and also produce physically feasible space charge fields that are capable of driving the proposed aging mechanism to the extent required View full abstract»

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  • Current-field and conductivity-field characteristics of thin layers: the predictions of the Bottger-Bryksin model

    Publication Year: 2001 , Page(s): 1003 - 1006
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (286 KB) |  | HTML iconHTML  

    Phonon-assisted hopping of electrons between spatially distinct locations is one of the basic transport mechanisms in solids. In the present contribution compare the current-field, and differential conductivity-field characteristics, calculated within the Bottger-Bryksin model applied to thin layers with spatially nonuniform distributions S(x) of hopping centers. In particular, we consider exponential and bi-exponential spatial distributions of centers, i.e. S(x) ∝ exp(-x/D), and S(x) -∝[exp(-x/D) + exp(-(L x)/D)], where L is the layer thickness, and D the distribution parameter. Although the model allows the calculations for both on-diagonal (energetic) and off-diagonal (positional) disorder, here we discuss only the case of discrete energy level of hopping centers. We show that the Bottger-Bryksin model predicts a strong 'tapping' effect in the case, where the surface densities of hopping centers at both contacts differ significantly. In such cases wide field intervals of negative differential conductivity are expected View full abstract»

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  • Positive streamer discharges along insulating surfaces

    Publication Year: 2001 , Page(s): 902 - 910
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (840 KB) |  | HTML iconHTML  

    By measuring the currents associated with the streamer discharge along silicone rubber surfaces, parameters of streamer propagation such as the minimum field of streamer crossing, the field of stable streamer propagation, the mean velocity and the streamer charge distribution have been analyzed and compared to the streamer discharge in air alone. Clear differences were observed in the measured currents for the individual surfaces at low background fields (285 kV/m). For higher fields the streamer crosses the gap almost independently of the surface type. The minimum streamer field was found to be slightly increased compared to air. The field of stable streamer propagation also was higher than in air. It is ~ 570 kV/m, larger than that of the streamer discharge in air (~ 500), under the same conditions. The streamer speed was found slightly increased in the presence of the silicone rubber surface and the distinction between the individual surfaces was modest. A discussion on possible mechanisms for the observed differences in the streamer speed and currents with and without the insulator surfaces is presented. The net positive charge of the streamer along an insulating surface seems to be distributed along the streamer channel rather than localized in the front part of the channel as the case for the streamer in air View full abstract»

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  • Dielectric windows for UHF partial discharge detection

    Publication Year: 2001 , Page(s): 953 - 958
    Cited by:  Papers (36)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (582 KB) |  | HTML iconHTML  

    Increasing the permittivity of the propagation medium inside a hollow tube lowers its cut-off frequency, allowing it to transmit a wider range of signal frequencies. This principle is applied to the design of dielectric windows that can be used to facilitate partial discharge (PD) detection at ultra high frequency (UHF) in a HV metalclad plant such as gas-insulated substation (GIS), power transformers and circuit breakers. External UHF couplers mounted on such windows can be removed or replaced without compromising the integrity of the insulation system. By increasing the signal power level incident on a window-mounted external UHF coupler, higher sensitivity to PD can be achieved. The problem is analyzed using waveguide theory and, using GIS as an example, improvements of ≈6 dB are demonstrated by means of coupler sensitivity measurements and experiments using PD sources View full abstract»

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Aims & Scope

IEEE Transactions on Dielectrics and Electrical Insulation contains topics concerned with dielectric phenomena and measurements with development and characterization of gaseous, vacuum, liquid and solid electrical insulating materials and systems.

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Reuben Hackam