The Study of VFTO Distribution in the Insulation System of IOCT Used in Traction Network
Zhonghuan Su,
Longfu Luo,
Jun Liu,
Zhongxiang Li,
Hu Luo,
Haonan Bai
Affiliations
Zhonghuan Su
College of Electrical and Information Engineering, Hunan University, Changsha 410000, China
Longfu Luo
College of Electrical and Information Engineering, Hunan University, Changsha 410000, China
Jun Liu
College of Electrical and Information Engineering, Hunan University, Changsha 410000, China
Zhongxiang Li
College of Electrical and Information Engineering, Hunan University, Changsha 410000, China
Hu Luo
College of Electrical and Information Engineering, Hunan University, Changsha 410000, China
Haonan Bai
Key Laboratory of Special Motors and High Voltage Electrical Appliances, Ministry of Education Shenyang University of Technology, Shenyang 110870, China
The FDS (Frequency-domain Dielectric Spectroscopy) of oil-immersed insulation paper, and semi-conductive paper with different moisture content, has been measured. The data measured are fitted as a function of frequency and moisture content using the amendatory Cole–Cole model utilizing the least square technique. Then, the broadband MTL model of the insulation system of IOCT (Inverted-type Oil-immersed Current Transformer) is established considering the capacitive electrodes thin layer, and the distribution parameters consider the moisture and frequency dependence. A new method for VFTO (Very Fast Transient Overvoltage) distribution calculation of insulation systems is proposed.
