Studies on mixing and separation of multiple insulation fault UHF partial signals in GIS
Xiaoxiao Zhao · 2017
In order to explore the mixing characteristics of UHF partial discharge (PD) signals in GIS, the mixing characteristics of UHF signals in GIS are studied by antenna theory and electromagnetic field simulation software (XFDTD). Theoretical analysis and simulation results show that convolution is the basic relationship between PD current signal and single UHF PD signal. PD mixing signal is linear and instantaneous mixing of single PD signal. They are also linear and convolution of PD current signal. The reverse process of those mixing modes is also discussed based on blind source separation and find out that it is an over-complete blind source separation problem to obtain single UHF PD signal from mixed one, what's more, it can be approximated to conventional blind source separation when the layout of UHF sensors are very compact.