Optical Detection of Partial Discharges Under Fast Rising Square Voltages in Dielectric Liquids

Partial discharge (PD) measurement of an insulation system is widely used as a diagnostic tool for the quality control high voltage apparatuses. In ac, conventional method PD detection well established. However, under square voltages such those generated across power electronic converters, cannot discriminate between PDs and switching transients. this context, paper demonstrates fast-rising by deploying photomultiplier tube. For this, experimental set-up generating unipolar (USV) waveforms developed, dV/dt in range 10-100 kV/μs. The device test (DUT) comprises needle-barrier plane configuration immersed dielectric liquids. Barriers differing permittivity thicknesses are chosen to with two types liquids, assess varying conditions. results thus obtained show lower partial inception (PDIV) USV than bipolar ac same DUT specimen. phase-resolved (PR) patterns exhibit higher occurrence during rising falling front waveform. Experimental demonstrate relevance PMT detector exhibiting