State Key Lab for Electrical Insulation and Apparatus;
Xi'an Jiaotong University;
Xi'an 710049;
China School of Electrical and Information Engineering;
Hunan University;
Changsha 410082;
China;
State Key Lab for Electrical Insulation and Apparatus;
Xi'an Jiaotong University;
Xi'an 710049;
China;
School of Electrical and Information Engineering;
Hunan University;
Changsha 410082;
China;
Technische Universitat Darmstadt;
64283 Darmstadt;
Germany;
Dept. of Electrical Engineering and Computer Science;
University of Manitoba;
Winnipeg;
Canada;