Switching Arc Phenomena in Transmission Voltage Level Vacuum Circuit Breakers

Preface
Introduction
Contents
1 High-Current Vacuum Arcs Phenomena at Transmission Voltage Level
	1.1 Introduction
	1.2 Threshold Current of High-Current Anode Mode Formation
		1.2.1 Influence of Dynamic Solid Angle on the Threshold Current
		1.2.2 Influence of Axial Magnetic Field on the Threshold Current
	1.3 Current Density of Anode Spots Subjected to Axial Magnetic Field
		1.3.1 Anode Current Density Distribution in Diffuse Vacuum Arcs
		1.3.2 Anode Spot Current Density
	1.4 Thermal Process of Anode Surface Driven by High-Current Anode Mode Vacuum Arcs
		1.4.1 Anode Erosion Caused by Blowing Effect in High-Current Anode Mode Vacuum Arcs Subjected to Axial Magnetic Field
		1.4.2 Modeling of Anode Erosion Formation by High-Current Anode Mode Vacuum Arcs
		1.4.3 Decay Modes of Anode Surface Temperature After Current Zero in Vacuum Arcs—Experimental Study
		1.4.4 Decay Modes of Anode Surface Temperature After Current Zero in Vacuum Arcs-Impact on Dielectric Recovery Strength
	References
2 Dielectric Recovery Properties After Current Interruption in Vacuum
	2.1 Free Recovery Processes After Diffused Vacuum Arcs Extinction
	2.2 Metal Vapor Density in Current Zero Region
		2.2.1 Cu Vapor Density
		2.2.2 Cr Vapor Density
	2.3 Taylor Cone Initiated on Contact Surface After High-Current Interruptions
	2.4 Dielectric Breakdowns
		2.4.1 Breakdown in Cathode Sheath: Metal Vapor and Residual Plasma
		2.4.2 Particles Induced Late Breakdown
		2.4.3 Mechanical Shocks and Late Breakdowns
	References
3 Vacuum Interrupters at Transmission Voltage Level
	3.1 Vacuum Insulation
		3.1.1 Contact Design Parameters and Lightning Impulse Voltage Breakdown Characteristics Under Large Contact Gaps
		3.1.2 Breakdowns in High Voltage Vacuum Interrupters with Large Contact Gap
		3.1.3 Cathode Arc-Melted Layer and Vacuum Insulation
	3.2 Vacuum Interrupter Contacts
		3.2.1 2/3 Coil-Type Axial Magnetic Field Contact
		3.2.2 Horseshoe-Type Axial Magnetic Field Contact
		3.2.3 Transverse Magnetic Field Contacts Subjected to Axial Magnetic Field
	3.3 X-Radiation for 126 kV Vacuum Interrupters
	References
4 Vacuum Circuit Breakers at Transmission Voltage Level
	4.1 Determination of Opening and Closing Velocities
		4.1.1 Anode Mode Diagram: A Determination of Opening Displacement Curve
		4.1.2 Determination of Opening Velocity Characteristic for a 126 kV Vacuum Interrupter with 2/3 Coil-Type Axial Magnetic Field Contact
		4.1.3 Determination of Opening Velocity Characteristic for a 126 kV Vacuum Interrupters with Horseshoe-Type Bipolar Axial Magnetic Field Contact
		4.1.4 Determination of Closing Velocity for Minimizing Percussion Welding Force
	4.2 Operating Mechanism and Mechanical Reliability
		4.2.1 Opening/Closing Displacement Curve and Spring Type Operating Mechanism Design
		4.2.2 Contacts Impact Phenomena
		4.2.3 Mechanical Endurance of a 126 kV Single-Break Vacuum Circuit Breaker
		4.2.4 Reliability in Closing Operation of Spring Type Operating Mechanism
		4.2.5 A Permanent Magnetic Actuator for 126 kV Vacuum Circuit Breakers
	4.3 Nominal Rated Current and Temperature Rise
	4.4 Type Test of a 126 kV Single-Break Vacuum Circuit Breaker
	References
5 Capacitive Current Switching in Vacuum
	5.1 Prestriking Phenomena and Inrush Current
		5.1.1 Capacitive Current Switching of Vacuum Interrupters and Inrush Currents
		5.1.2 Asymmetrical AC Field Emission Current Characteristics of Vacuum Interrupters Subjected to Inrush Current
		5.1.3 Prestrike Electric Field Characteristics When Making Inrush Current in 40.5 kV Vacuum Interrupters
		5.1.4 Impact of Inrush Current on Field Emission Current and Voltage Distribution for Double Vacuum Interrupters in Series
		5.1.5 Inrush Current Interruption and Contact Gap Breakdown
	5.2 Capacitive Current Switching and Magnetic Field Between Contacts
		5.2.1 Prestrike Inrush Current Arc Behaviors in Vacuum Interrupters Subjected to a Transverse Magnetic Field and an Axial Magnetic Field
		5.2.2 Capacitive Current Switching Performance of Vacuum Interrupters with Three Kinds of Contacts
	5.3 Capacitive Current Switching and Contact Materials
		5.3.1 Inrush Current Prestrike Arc Behaviors of Contact Materials CuCr50/50 and CuW10/90
		5.3.2 Capacitive Current Switching Performance of Vacuum Interrupters with Three Contact Materials
	5.4 High-Frequency High-Voltage Impulse Conditioning and Capacitive Current Switching of Vacuum Interrupters
	5.5 Back-To-Back Capacitor Bank Switching Technology
		5.5.1 An Outdoor Double-Break 40.5 kV Vacuum Circuit Breaker for Back-To-Back Capacitor Bank Switching
		5.5.2 An Indoor 40.5 kV Vacuum Circuit Breaker for Back-To-Back Capacitor Bank Switching
	References