Gaseous Dielectrics

Gaseous Dielectrics V presents the proceedings of the Fifth International Symposium on Gaseous Dielectrics, held in Knoxville, Tennessee on May 3-7, 1987. This book discusses the effective coupling between basic and applied research and technology achieved in this area.

Organized into 12 chapters, this book begins with an overview of the status of theoretical calculations of excitation and ionization coefficients for electrons. This text then provides an extensive investigation into different phases of discharge development in electronegative gases. Other chapters consider the use of sulfur hexafluoride as a dielectric medium in rail systems and gas circuit breakers. This book reviews as well the primary requirements for a successful gas analysis program, with emphasis on measurement and interpretation methods. The final chapter deals with the progress in dielectric quality assurance of gas insulated substations (GIS), which has resulted from improved scientific knowledge of significant phenomena.

This book is a valuable resource for electrical and electronics engineers.

Contenu

Chapter 1: Basic Physics of Gaseous Dielectrics
Excitation and Ionization Coefficients
Discussion
Laser-Enhanced Electron Attachment and Its Possible Application for Optical Switching
Discussion
Galvanooptical Measurement of Photodetachment from Negative Ion Swarms in Oxygen
Discussion
Electron Collision Cross Sections for C2F6 and N2O
Discussion
A Macroscopic Model of Electron Swarm Motion in Non-Equilibrium Regions
Non-Equilibrium Description of Electrons in a Gas Influenced by Space-Time Varying Electric Fields
Temperature Dependent Electron Transport and Rate Coefficient Studies for e-Beam-Sustained Diffuse Gas Discharge Switching
Time Dependent Conductivity Studies of Electron Thermalisation in Simple Gases
Chapter 2: Basic Mechanisms
Breakdown Mechanisms in Electronegative Gases
Discussion
Predischarge Development in N2 and SF6 at High Gas Pressures
Discussion
Effect of Temperature on the Uniform Field Breakdown Strength of Electronegative Gases
Discussion
The Influence of Thermal Ionization on Electrical Breakdown
Discussion
Contribution to a Unified Theory of the Leader Processes
Discussion
Mechanism of a Short Gap Breakdown
Experimental Investigation of the Streamer to Leader Transition in SF6 Under Negative Polarity
Modeling of Leader Branching in Electronegative Gases
The Leader Inception Characteristics in Positive Sphere-Plane Air Gaps
Velocity Measurements in Mixtures of SF6 and N2 in Non-Uniform Field Gaps Under Positive Impulse Voltage
Chapter 3: Gas Decomposition/Reacnons/Toxicity
Decomposition of SF6 by Arc Discharge and the Determination of tne Reaction Product S2F10
Discussion
Corona-Induced Decomposition of Dielectric Gases
Discussion
Investigations of the Toxicological Action of Spark-Decomposed SF6 in Mammalian Cells
Discussion
Degradation of the Dielectric Properties of SF6 Due to the Presence of Gaseous Impurities; Deviations of the "Paschen's Law" at High Pressures for Positive Polarity
Discussion
The Influence of Impurities on the Dielectric Strength of SF6 for Positive Polarity; The Nature of Initiatory Electrons
Formation and Stability of SF5 and S2F10
SOF4 Production in Spark Breakdown of SF6/O2 Mixtures
Assay of SF6 and Spark-Decomposed SF6 for Mutagenic Activity in the CHO/HGPRT Mammalian Cell System
Chapter 4: Diagnostics/Field Probes
Gas Analysis as a Diagnostic Tool for Gas-Insulated Equipment
Discussion
On the Possibility of Diagnostics of GCB and GIS by Gas Chromatography
Discussion
On the Electrostatics of Probe Measurements of Surface Charge Densities
Discussion
Measurement of Accumulated Charge on Dielectric Surfaces with an Electrostatic Probe
Discussion
The Effect of Humidity on Space Charge Growth in Short Air Gaps
Laser Probing of Air Gaps Under AC Conditions
Chapter 5: Gases/Mixtures for GIS Transformers and Circuit Breakers
Predicting the Breakdown Strength of Mixtures from Basic Data
Discussion
The Dielectric Strength of Dichlorotetrafluoroethane (1,2-C2Cl2F4) Determined in a Combined Swarm/Breakdown Study
Discussion
The Influence of Gaseous Admixtures to SF6 on the Corona Stabilized Regime at AC and at Positive Impulse Voltage
Discussion
Nonuniform Field Corona and Breakdown Characteristics of SF6/Freon Mixtures
Discussion
Effect of a Trichlorotrifluoroethane Vapor Additive on Dielectric Strength of SF6 Gas
Measurement of the Figure of Merit M for Several Perfluorocarbon Gases
Breakdown Voltage Measurement of Some Vapor-Mist Dielectrics
Chapter 6: Gaseous Media for Discharge Chemistry and Etching/Coron
Gaseous Media for Plasma Chemistry and Etching
Discussion
Practical Implications of Dry Plasma Processing
Discussion
Important Considerations for Optimizing Production Rates in RF Discharge Chemistry
Discussion
Negative DC Corona Discharge in SF6 for Highly Divergent Fields
Discussion
Calculation of Corona Onset Voltage with Space Charge Effect
DC Corona Control in Coaxial Gas Insulating Systems
Chapter 7: Gas Engineering for Pulsed Power and Switching
Gas Engineering for Pulsed Power and Switching
Discussion
Penning Ionization Ternary Gas Mixtures for Diffuse Discharge Opening Switches
Discussion
Gas Mixtures for Spark Gap Closing Switches with Emphasis on Efficiency of Operation
Discussion
The Influence of Transverse Magnetic Fields on Glow Discharges in He/SF6 Gas Mixtures
Discussion
Analysis of the Cathode Fall of Glow Discharges in a He/SF6 Gas Mixture
Gas Engineering Studies for High Pressure Self-Sustained Diffuse Discharge Closing Switches
Diffuse Discharges in High-Pressure Mixtures of c-C4F8 and He
Chapter 8: Gas Breakdown Under Steep-Fronted Voltages
Statistical Breakdown Process in SF6 and Breakdown Voltage Calculations
Discussion
Formative Time Lags in SF6-N2 Gas Mixtures for Different Field Distribution
Discussion
Voltage-Time Characteristics of Impulse Breakdown in SF6 Gas
Discussion
Spacer Flashover Time Lags in SF6 Under Fast-Front Impulse Voltages
Discussion
Breakdown Volt-Time Characteristics in SF6 Mixtures for a Coaxial Cylinder Gap
Effect of Field Divergence on the Lightning Impulse Breakdown of Rod-Plane Gaps in N2/SF6 Mixtures
Free Particle Initiated Breakdown of SF6 Under Voltages of Different Time Dependence
Chapter 9: New Developments in Gas-Insulated Equipment/Gas Handling
Development of ±500 kV HVDC Gas-Insulated Switchgears
Discussion
A Manufacturer's Experience in the Cyclic Use of SF6 Gas
Discussion
Volt-Time Curves of Disconnector-Generated Fast Transients inside GIS
Discussion
Insulation Characteristics of Separate Cooling Sheet Winding-Type Gas-Insulated Transformer
Discussion
Recovery Strength of SF6-Insulated Gaps Stressed by Double Lighting Impulse Voltages
Conduction Currents in Gas-Insulated Switchgear for Low Level DC Stress
Effects of Electrode Surface Roughness on Dark Current and Switching Impulse Breakdown Voltage in Compressed SF6 Gas
Mixing Rates and Diffusion of Various Gases and Moisture into SF6
Chapter 10: Gas/Insulator Interface/Flashover
Surface Changes Induced by Low Kinetic Energy Products from Corona Discharge on Epoxy Resin in Air
Discussion
Avalanches Near a Dielectric Spacer in Nitrogen Gas
Discussion
Measurement of the Temporal Decay of Charges on Insulator Surfaces
Discussion
Effect of Ribs on Surface Discharge in SF6 Gas
Discussion
Application of ESCA in GIS Spacer Surface Analysis
Discussion
Study of the Charge Build-Up on Dielectrics Submitted to Corona Discharge a…