Non‐electrical Methods for PD Measurement

Abstract

This chapter deals with non-electrical methods of partial discharge (PD) detection. Optical PD detection is one of the most challenging PD measurement techniques, which may reveal the long time-unknown complex mechanism of discharge. The optical PD detection is based on the detection of the light generated due to ionization, excitation, and recombination process during the existence of discharge. PD activity generates electromagnetic waves, acoustic waves, current PD pulses, and byproducts. There are two techniques used for the detection of Acoustic Emission (AE) PD signals: by hand-held AE PD receiver, and by instrument-based AE detection. Various types of acoustic noise occur during AE PD measurement, mainly low-frequency background noise. PD activity generates various types of measurable signals, including the chemical byproducts. These byproducts have a strong tendency to dissolve in the liquid insulation present or react with a catalyst to form a corrosive gas.