Last edited by Musar
Friday, May 1, 2020 | History

3 edition of Characteristics of Streamer Discharges in Air and Along Insulating Surfaces found in the catalog.

Characteristics of Streamer Discharges in Air and Along Insulating Surfaces

Lan Gao

Characteristics of Streamer Discharges in Air and Along Insulating Surfaces

  • 376 Want to read
  • 8 Currently reading

Published by Uppsala Universitet .
Written in English

    Subjects:
  • Electronics - General,
  • Physics,
  • Science,
  • Science/Mathematics

  • Edition Notes

    SeriesComprehensive Summaries of Uppsala Dissertations, 514
    The Physical Object
    FormatPaperback
    ID Numbers
    Open LibraryOL12854201M
    ISBN 10915544668X
    ISBN 109789155446680

    This charge begins to migrate upward through buildings, trees and people into the air. When this upward rising positive charge – an upward leader or streamer – meets with the leader in the air above the surface, a conductive path is completed. Electrons surge along . Aeration tank-turbulence, color, and amount of surface foam and scum Influent-color and level of inflow Secondary clarifier-effluent clear or turbid, type of solids on surface, and influent When the lab data varies widely from one day to the next, which items should be checked Lab procedures for errors Sampling location Time samples were collected. the gases CO 2, N 2 and dry air are examined as possible substitutes for SF 6 at pressure range from to 1 MPa. Their behaviour under AC and LI stresses is investigated. The study compares the breakdown characteristics of these gases and their mixtures in case of clean boundary surfaces as well as for the particle contaminated. Gas-insulated switchgear (GIS) is a common electrical equipment, which uses sulfur hexafluoride (SF6) as insulating medium instead of traditional air. It has good reliability and flexibility. However, GIS may have internal defects and partial discharge (PD) is then induced. PD will cause great harm to GIS and power system. Therefore, it is of great importance to study the intrinsic Cited by: 2.


Share this book
You might also like
Malarial mimicry

Malarial mimicry

The Underground.

The Underground.

manual for manpower accounting in higher education

manual for manpower accounting in higher education

Urban public transit needs, State of Florida, 1971-1990.

Urban public transit needs, State of Florida, 1971-1990.

Maximum wave heights and critical water depths for irregular waves in the surf zone

Maximum wave heights and critical water depths for irregular waves in the surf zone

Beaumarchais: plagiarist and innovator

Beaumarchais: plagiarist and innovator

Writing

Writing

Watch and clock making

Watch and clock making

three part Harvard business review symposium on Businesses need for bright young people

three part Harvard business review symposium on Businesses need for bright young people

Hungary

Hungary

Evaluation of a subunit vaccine to infectious hematopoietic necrosis virus

Evaluation of a subunit vaccine to infectious hematopoietic necrosis virus

Forty Hadiths

Forty Hadiths

My dear Timothy

My dear Timothy

Gaye affair

Gaye affair

Across Five Aprils

Across Five Aprils

Characteristics of Streamer Discharges in Air and Along Insulating Surfaces by Lan Gao Download PDF EPUB FB2

Parameters concerning the propagation of streamer discharges in air and along insulator surfaces are thus of importance for understanding the way in which the streamer characteristics can be influenced. The studies reported in this thesis were made on streamer discharges in air and over insulating surfaces at atmospheric by: 6.

Download Citation | Characteristics of streamer discharges in air and along insulating surfaces | Power quality is dependent on the dielectric properties of the insulators used throughout the Author: Lan Gao.

streamer discharges propagating along insulating surfaces, the results of these studies made it possible to separate and quantify the effects of the dielectric constant and the surface properties on the streamer discharges.

In the third phase a comprehensive computer algorithm was developed to simulate 3-dimensional propagation of positive streamer discharges in air and along dielectric surfaces. This paper reviews the main contributions of the CIGELE research team to the dynamics of streamer discharges along ice surfaces.

These investigations were mainly performed under lightning impulse voltage, in atmospheric air. High-speed streak photography techniques were used to observe the streamers propagating between a rod-plane configuration half-submerged in ice : Masoud Farzaneh, Issouf Fofana.

discharge characteristics such as shape and amplitude of the discharge current, the streamer zone length and structure depend on the permittivity of the barrier, its thickness, its surface state and its position relative to the needle electrode.

With a closer position the influence of the barrier is more. It is shown that streamer discharges may develop in different modes depending upon particular conditions and are capable of propagating along solid surfaces in the direction transverse to the.

Propagation Characteristics of Surface Discharge under Impulse Application Voltage Introduction Flashover on insulator surface in air at atmospheric pressure occurs as a sequence of several processes that leads to the formation of a plasma channel which bridges the electrode gap. With the help of Lichtenberg figure technique, the two different stages of surface discharge -- corona streamer and gliding arc, can be distinguished on the analogy model of conductor-plane.

Typical pictures are shown in Fig. 2 (a) and Fig. 2 (b). Fig.2(a). The Lichtenberg figure with corona : W.D. Wang, C.R. The photo shows electric discharges in air at an insulating surface.

(Photo: Geir Mogen) The test object is a plate of insulating material (usually mm thick) placed on top of a disc-shaped ground electrode. A high voltage electrode is placed just above the test object (1 to 2 mm). When energized, the surface of the test object is subjected.

STUDY OF THE ELECTRICAL FLASHOVER OF AN INSULATING SURFACE POLLUTED BY AN ALTERNATING CURRENT DISCHARGE A. Smaili 1 D. Mahi 2 B. Zegnini 2 1 Département de Génie Electrique - Université Abderrahmane Ibn Khaldoun de Tiaret- Algérie 2 Laboratoire d'étude et développement des matériaux semi conducteurs et diélectriques, Département de GénieFile Size: 82KB.

the pure air gap discharge, and the latter refers to the gas discharge along a solid surface. Breakdown and flashover are collectively referred as discharge.

The gas discharge will only. cause a temporary loss of the insulation. Experiments on the surface discharge were described in the literature ([1], [2]). The surface discharge can slide on low-conductivity material (PTFE, PMMA, ceramics, polycarbonate) and conductors (water, ice, earth, ).

These and intermediate variants can be presented with simple scheme (see Size: KB. Basic opto-electrical characteristics of a single micro-discharge generated in a surface DBD reactor with a coplanar electrode arrangement were studied with nanosecond time resolution.

The discharge electrode geometry based on machinable glass–ceramic was optimized in orderCited by: Abstract—Dielectric barrier discharge (DBD) is the electrical discharge between the electrodes in the presence of an insulating barrier. In this study, double-layered solid dielectric barriers and plane-plane electrode system are used to examine the DC discharge characteristics of air File Size: KB.

This paper presents a peculiar-surface discharge characteristic in the presence of particle around an epoxy surface. Surface discharge experiments were conducted to measure partial discharge (V P) and surface flashover voltage (V F) with particle locations from the epoxy surface in atmospheric : Dong Young Lim, Seung Wook Jee, Sungwoo Bae, Young Kil Choi.

Breakdown in electronegative gases, time lags for breakdown, streamer theory of breakdown in gases, Paschen’s law, Breakdown in non-uniform field and corona discharges, Post breakdown phenomena and applications, practical considerations in using gases for insulation.

where C D = is the capacitance of the dielectric layers; C G = is the capacitance of the air gap and R is the equivalent resistance of the DBD discharge. Here A is the electrodes area, d is the thickness of the dielectric layer, k is the dielectric constant and x is the discharge gap width.

In surface DBD, if the voltage in the discharge space V p keeps rising, more microdischarges are produced at new locations along the edge of the exposed electrode and the discharge area is Cited by: 9. 2 SF 6 insulation systems and their monitoring + Show details-Hide details p. 37 –76 (40) This chapter reviews the basic ionisation processes which occur in SF 6, the streamer mechanism which controls breakdown under relatively uniform field conditions, and the influence of electrode surface roughness on breakdown at high characteristics of the partial discharges (corona.

surfaces and discharge processes, especially, the develop-ment of pre-discharge phenomena like streamers on in-Ž.

sulating surfaces. These processes, which always precede the actual flashover, are initiated when the applied volt-age in the system is approaching the critical breakdown value. Streamer discharges have been studied extensively, both theoretically and experimentally.

However, the mecha. Types of coronas and corona conduction corona discharge is, by definition, a gas discharge where the geometry confines the gas ionizing.

processes to high-field ionization region(s) around the. Two-dimensional numerical simulations of streamer development in a surface dielectric barrier discharge excited by a voltage pulse with a duration of 30–50 ns in atmospheric air show that the streamer propagation velocity is mainly governed by the velocity of potential diffusion along streamer channels.

The calculated streamer length substantially exceeds the experimentally observed one due Cited by: pollutants, surface modifications [1], lightings, and plasma displays [2]. Non-thermal plasma can be established at atmospheric pressure by using the dielectric barrier discharge (DBD) which consists of a dielectric layer in contact with either one of a pair of electrodes.

The electrical discharge characteristics of the DBD are dependent on several. The book is written for students as well as for teachers and researchers in the field of High Voltage and Insulation Engineering. It is based on the advance level courses conducted at TU Dresden, Germany and Indian Institute of Technology Kanpur, India.

The book has a novel approach describing the fundamental concept of field dependent behavior of dielectrics subjected to high voltage. Faculty of Engineering at Shoubra High Voltage Engineering (1) Electrical Engineering DepartmentE. Page 1 Of 10 CHAPTER 4 insulator surfaces leading to gradual breakdown along the surface of the insulator.

failure also occurs due to partial discharges which are brought about in the air pockets inside the insulation.

This File Size: KB. Streamer theory predicts the development of a spark discharge directly from a single avalanche. The space charge produced in the avalanche causes sufficient distortion of the electric field that those free electrons move towards the avalanche head and in so doing generate further avalanches in a process that rapidly becomes cumulative.

The initiation and propagation of discharge in the air gap and along the ice surface were observed, and the discharge propagation velocities at different stages were recorded. These studies have revealed, beyond the main discharge, the presence of luminous spots which determine the path of discharge and accelerate its by: “tiny arc” along the insulation surface can be represented by partial discharge activity.

Figure 5 illustrates the failure mode of deteriorated insulation related to the intensity of partial discharge measurements. Figure 6 illustrates a circuit breaker bushing which as progressive tracking highlighted for presentation purposes.

High Voltage aims to attract original research papers and review articles. The scope encompasses high-voltage power engineering and high voltage applications, including experimental, computational (simulation and modelling) and theoretical studies. High Voltage is a fully open access journal co-published with CEPRI (the China Electric Power.

The book begins by describing the insulating and arcing characteristics of SF6, followed by an introduction to the gas dielectrics performance of SF6 gas mixtures with buffer gases.

The latest findings on new environmentally friendly insulating gases are described in detail, and suggestions for practical application are also : Springer-Verlag Berlin Heidelberg. Applications.

The properties and effects of electric discharges are useful over a wide range of magnitudes. Tiny pulses of current are used to detect ionizing radiation in a Geiger–Müller tube.A low steady current can be used to illustrate the spectrum of gases in a gas-filled tube.A neon lamp is an example of a gas-discharge lamp, useful both for illumination and as a voltage regulator.

The characteristics of breakdown voltages against the position of floating metallic particles in atmospheric air are investigated experimentally to provide fundamental parameters determining the breakdown voltage in the presence of floating objects around high voltage power apparatus by an air insulation.

Insulation and Breakdown In Gases Ionisation and Avalanche Formation Townsend and Streamer Breakdown Paschen Law: Gas Type Breakdown Along Insulator Inhomogeneous Fields, Pulsed Voltages, Corona Insulating Liquids Solid Insulation Breakdown types, Surface tracking, Pa rtial discharges, Polarisation, tan.

multi-streamer electrode geometry, however, is problematic Figure 2. Image of discharge showing electrodes and spatial ROI, fitted around typical µm streamer width near HV anode. forlaser-baseddiagnostics,especiallyforpointmeasurements, and thus the electrodes were modified to a point-to-plane geometry for the purposes of these File Size: 1MB.

@article{osti_, title = {Study of the homogeneity of the current distribution in a dielectric barrier discharge in air by means of a segmented electrode}, author = {Malashin, M. V., E-mail: [email protected] and Moshkunov, S. and Khomich, V. Yu.}, abstractNote = {The current distribution in a dielectric barrier discharge in atmospheric-pressure air at a natural humidity of 40–60%.

Formation of Streamer Discharges from an Isolated Ionization Column at Subbreakdown Conditions Ningyu Liu,* Burcu Kosar, Samaneh Sadighi, Joseph R. Dwyer, and Hamid K. Rassoul Department of Physics and Space Sciences, Florida Institute of Technology, Melbourne, FloridaUSA (Received 12 June ; published 10 July )Cited by: ns.

The second discharge is also spreading on the surface of the second dielectric layer and its front is located at r= cm at ns. The third positive streamer, with a high electron density of cm 3 in the head (x cm), (Fig.1) propagates from the second dielectric surface in the direction of the.

The streamer discharges are effectively used for biological and chemical cleaning of air and water. Uniform streamer discharges were obtained in water at pulsed electric loading.

The volume of these discharges exceeds cm 3 and the energy delivered to the discharge reached 40– J depending on the applied voltage. The reliable and durable reactor for water treatment by pulsed streamer Cited by: v CONTENTS PREFACE xi ACKNOWLEDGMENTS xv CHAPTER 1 INTRODUCTION 1 Electric Charge and Discharge 2 Electric and Magnetic Fields and Electromagnetics 3 Dielectric and Electrical Insulation 5 Electrical Breakdown 5 Global Breakdown 6 Local Breakdown 6 Corona, Streamer and Aurora 6 Capacitance and Capacitor 8 Stray Capacitance 9.

The dielectric breakdown strength of dry air, at Standard Temperature and Pressure (STP), between spherical electrodes is approximately 33 kV/cm. This is only as a rough guide, since the actual breakdown voltage is highly dependent upon the electrode shape and size.

Strong electric fields (from high voltages applied to small or pointed conductors) often produce violet-colored corona discharges. The book begins by describing the insulating and arcing characteristics of SF6, followed by an introduction to the gas dielectrics performance of SF6 gas mixtures with buffer gases.

The latest findings on new environmentally friendly insulating gases are described in detail, and suggestions for practical application are also provided.3/5(1).PhD on streamer discharge development over dielectric surfaces.

The works included designing and organizing experimental procedures, buying and installing the necessary equipment, conducting the experiments, registering various characteristics of the discharge itself and the surrounding : Ph.D.

(Eindhoven University of .Yuriy Serdyuk conducts research mainly focusing on phenomena in electric insulating materials exposed to strong electric fields.

These include processes associated with transport of electric charges in gaseous, liquid and solid insulating media as well as in their compositions and through interfaces between them.