Time-Frequency Analysis and Feature Extraction of UHF Partial Discharge Signal by Using Cumulative Energy Technique
Ultra high frequency (UHF) measurement gradually become a recognized partial discharge (PD) detection approach, and is widely used in condition monitoring of high voltage equipment such as GIS and transformer. In general, insulation condition diagnostic is performed by interpreting PRPD patterns and UHF signals characteristics. This paper presents the time-frequency analysis and feature extraction procedure of UHF PD signal by using cumulative energy technique.
Four types of typical defect models in GIS are designed, and their UHF signals are detected with a high sampling rate instrument. The cumulative energy (CE) in time and frequency domain are adopted to analyze the difference between UHF signals of various defects. The characteristic parameters including width, sharpness and gravity are extracted from the CE to represent the main features of UHF signal. A PD signal separation procedure by clustering the extracted features with fuzzy maximum likelihood algorithm is presented, and its effectiveness is examined with multiple PD source measurement experiments.
About Keynote Speaker
Guan-Jun ZHANG (M’02) was born in Shandong Province, China, in October 1970. He received the B.S., M.S. and Ph.D. degrees in electrical engineering from Xi’an Jiaotong University (XJTU), Xi’an, China, in 1991, 1994 and 2001, respectively.
From July 1994, he worked as a Teacher Assistant with the State Key Laboratory of Electrical Insulation and Power Equipment and the School of Electrical Engineering at XJTU, and since June 2004, he has been a full Professor with XJTU. From October 1998 to September 1999, he was a Visiting Researcher with Tokyo Institute of Technology, Tokyo, Japan, engaged in electroluminescence and discharge phenomena of solid insulating materials. From August 2006 to February 2007, he was a Senior Visiting Fellow with Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ, US, engaged in secondary electron emission characteristic and plasma simulation. From August to October 2008, he was a Japan Society for the Promotion of Science (JSPS) Fellow with Saitama University, Japan, engaged in flashover physics in vacuum. His current research interests concentrate on high voltage insulation and discharge phenomena, especially dielectric response phenomena and condition maintenance of oil-paper insulation system, surface discharge and flashover across solid insulation, low temperature plasma and biomedical applications.
He has published more than 150 journal articles and conference papers and 12 Chinese patents. He received 2003 China National Top 100 Excellent Doctoral Dissertation Award, 2004 China New Century Excellent Talents in University, 2006 China Fok Ying Tong Research Award for University Young Teachers, 2008 IEEE Chatterton Young Investigator Award of 23rd International Symposium on Discharges and Electrical Insulation in Vacuum (ISDEIV), 2011 Distinguished Young Scholar of National Natural Science Foundation of China (NSFC), and other awards and prizes from Chinese Government.
He has served as the international advisory committee member, program committee member, secretary, section chair/co-chair for IEEE DEIS and other conferences for more than ten times, such as CMD, ISEIM, ICPADM and ACED, etc.