Detection and wavelet analysis of acoustic emission signal from partial discharge captured by multimode optical fiber and piezoelectric sensors in insulation oil

High-voltage transformer is the most critical and expensive component in a power system network in order to ensure the stability of the system. Partial discharge (PD) detection is a technique widely used for high voltage equipment insulation condition monitoring and assessment. In this paper, the characteristics of two acoustic sensors multimode fiber optical (FO) and piezoelectric (PZT) sensor have been successfully explored and monitor the condition of high voltage equipment insulation. Both the sensors were placed in an oil tank in which optical breakdown was produced by neodymium-doped yttrium aluminum garnet (Nd:YAG) laser (1064 nm) device. The optical signal of light source was linked by a photodetector which was also connected with multimode fiber (MMF) by means of a fiber optical adapter. The data obtained by both sensors were then analyzed in time and frequency domain.