Partial discharge multispectral detection in air with a SiPM-based sensor

Partial discharge (PD) is one of the reasons for the insulation deterioration in power equipment. As an intrinsic PD characterization method, optical detection is always just employed as a tool for laboratory study. With the development of solid-state photosensitive semiconductor device, it provides the possibility for implanting tiny photosensitive devices within the power equipment. In this paper, a SiPM-based PD light detector was designed for power supply and eliciting signal from SiPM. In order to compare the SiPM with other traditional PD detection methods, a synchronous PD measurement system was built to detect PD in optical and electrical method simultaneously. In addition, the PD light signals at different spectrum were detected by adding filters on the surface of SiPM. The results show that that SiPM has the same PD detection ability as that of high frequency current transformer (HFCT) and photomultiplier tube (PMT). There are some differences in the proportions of spectral components obtained by SiPM for different insulation defects, which provides an insight for insulation status evaluation.