Propagation analysis of electromagnetic wave radiated by partial discharge in single phase and three phase 150 kV Gas Insulated Switchgear

Gas Insulated Switchgear (GIS) has high reliability. However, partial discharge (PD) may occur. PD may lead the insulation breakdown. It is needed to detect PD before breakdown occurs. PD emits electromagnetic (EM) wave. UHF detection method is the most effective method to detect PD induced EM wave in GIS. The characteristics of EM wave propagating through GIS are needed to optimize sensor position for partial discharge detection. This paper discusses the propagation of PD induced EM wave in single phase and three phase 150 kV GIS. The difference between single phase and three phase GIS cause different electromagnetic wave propagation characteristic in GIS. By knowing the difference, UHF sensor settings can be determine. The simulation results show that single phase GIS has higher transmission rate, voltage intensity, and dominant frequency spectra than three phase GIS.