Vacuum circuit breakers are widely used in distribution power systems for their advantages such as maintenance free and eco-friendly. Nowadays, most circuit breakers used at transmission voltage level are SF6 circuit breakers, but the SF6 they emit is one of the six greenhouse gases defined in Kyoto Protocol. Therefore, the development of transmission voltage level vacuum circuit breaker can help the environment. The switching arc phenomena in transmission voltage level vacuum circuit breakers are key issues to explore. This book focuses on the high-current vacuum arcs phenomena at transmission voltage level, especially on the anode spot phenomena, which significantly influence the success or failure of the short circuit current interruption. Then, it addresses the dielectric recovery property in current interruption. Next it explains how to determine the closing/opening displacement curve of transmission voltage level vacuum circuit breakers based on the vacuum arc phenomena. After that, it explains how to determine key design parameters for vacuum interrupters and vacuum circuit breakers at transmission voltage level. At the end, the most challenging issue for vacuum circuit breakers, capacitive switching in vacuum, is addressed. The contents of this book will benefit researchers and engineers in the field of power engineering, especially in the field of power circuit breakers and power switching technology. 

Zhiyuan Liu is a professor in Xi'an Jiaotong University, Xi'an, China. He is a senior member of IEEE. He received the B. Sci. and M. Sci. degrees in electrical engineering from Shenyang University of Technology, Shenyang, China in 1994 and 1997 respectively. He received the Ph.D degree in electrical engineering from Xi'an Jiaotong University, Xi'an, China in 2001. He held the post of Postdoctoral in Xi'an Jiaotong University from 2003 to 2005.He worked for global research center Shanghai of General Electric company from 2001 to 2002. Since 2003, he has been working in state key laboratory of electrical insulation and power equipment, department of electrical engineering, Xi'an Jiaotong University, Xi'an, China. He is primarily involved with research on vacuum arc theory and development of transmission voltage level vacuum circuit breakers. He has coauthored 2 books in Chinese and he published over 200 technical papers. He holds more than 30 Chinese patents and 1 US patent.He is a member of the current zero club. He was a member of CIGRE working group A3.27 "The impact of the application of vacuum switchgear at transmission voltages" and he was a member of CIGRE working group JWG A3/B4.34 "Technical requirements and specifications of state-of-the-art DC switching equipment". He is a member of CIGRE working group A3.38 "Shunt Capacitor Switching in Distribution and Transmission Systems: Verification by Tests and Performance in Service".

High-Current Vacuum Arcs Phenomena at Transmission Voltage Level.- Dielectric Recovery Properties after Current Interruption in Vacuum.- Closing/Opening Displacement Curve of Transmission Voltage Level Vacuum Circuit Breakers.- Vacuum Interrupters at Transmission Voltage Level.- Vacuum Circuit Breakers at Transmission Voltage Level.- Capacitive Switching in Vacuum.