Optical Partial Discharge Diagnosis in SF6 Gas-Insulated System With SiPM-Based Sensor Array

This paper aims to promote optical partial discharge (PD) detection from laboratory scale to practical application for sulfur hexafluoride (SF
₆
)-insulated power equipment. First, a micro silicon photomultiplier (SiPM)-based PD sensor is evaluated for detecting PDs in SF
₆
gas and is proven to have the equivalent properties with pulse current acquisition and vacuum photomultiplier tube in terms of the signal-to-noise ratio, pulse resolution, and linearity. Then, a double-spectral PD sensor based on SiPM is first proposed and developed to realize a more specific PD diagnosis. It is demonstrated that by using the double-spectral PD sensor not only stochastic PD patterns can be obtained for PD recognition, but PD severity can be estimated as well.