Numerical Modeling of Partial Discharge in a Void Cavity Within High-Voltage Cable Insulation

Abstract

Partial discharge (PD) in the void cavity inside the insulation of the high-voltage (HV) cable is one of the critical problems. This article describes an approach to investigate the spatial distribution of plasma species related to PD dynamics in an ellipsoid void. The plasma dynamics of this type of discharge has been simulated using a self-consistent 2-D model. The ellipsoid void has the longest diameter of 1.5 mm and the shortest diameter of 0.4 mm and it is located at 6.8 mm from the center of the HV. The results show that there are two current pulses during each cycle of the applied voltage. The current pulses were obtained at the ends of the ellipse. The results of the spatial distribution for the charged species showing that both O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> and O <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-</sup> are a dominated species. The simulation results revealed, in later PD processes, the N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> and O <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-</sup> start to concentrate at the concave surface of the ellipsoid ends of the void.