Signal Analysis of Partial Discharge Defects in SF6 and C4F7N/CO2 Mixture

As the demand for power equipment using environmentally friendly gas increases, it is necessary to study the partial discharge (PD) under environmentally friendly gas conditions. Recently, the C
4
F
7
N/CO
2
mixture has attracted attention as an environmentally friendly gas to replace SF
6
gas. Traditional partial discharge analysis has been mainly pattern analysis based on phase-magnitude data. In this paper, the occurrence patterns are compared by phase-pulse number distribution and phase-maximum magnitude distribution based on phase-magnitude data under corona and surface discharge conditions. Similarities and differences are presented by comparing the shape and frequency band of the PD pulses measured by the sensor.