中文摘要：

ZHOU Yuanxiang was born in Fujian Province, China in 1966. He received the B.S. ,M.S. and Ph.D. degrees from Tsinghua University, China ,and Akita University, Japan in 1988, 1991 and 1999,respectively. From 1999 to 2000, he did research in NIRE, AIST, Japan as a NEDO t~llow. Now he is a professor of Tsinghua University and Deputy Secretary-general of China Electrotechnical Society. His interests include organic and inorganic dielectrics, high voltage and insulation technol-ogy, electrical equipment and onsite detection and diagnosis. ZHANG Ling was born in Fujian Province, China in 1987. He received the B.S. degree from Tsinghua University, China in 2010. He is now a Ph.D. candidate in High Voltage Laboratory of Departroent of Electrical Engineering in Tsinghua Universi- ty. His research field is space charge phenomenon in insulation materials, nanodielectrics and PEA technique. SHA Yanchao was bom in Zhangjiakou city, Hebei Province, China in 1985. He received the B.S. degree in electrical engineering from Chongqing University, China in 2009. He is currently pursuing the Ph.D. degree in Tsinghua University, Beijing, China. His interests include dielectric insulation and partial discharge in transformer insulation system. He is an IET member. TIAN Jihuan was born in Shanxi Province, China in 1981. He received the B.S. degree in 2004 .And he obtained the M.S. and Ph.D. degrees fi＇om Tsinghua University, China in 2009. He has done a post-doc research in High Voltage Laboratory in the Department of Electrical Engineering in Tsinghua Univer- sity, China. His research inte~sts include computational electromagnetics and fluid dynamics, degradation, breakdown and space charge phenomenon in dielectric insulating materials.