Impulse Breakdown Characteristics of Soil-Enhancement Material Mixtures

This paper presents and analyses the results of soil mixed with controlled amount of enhancement material (EM) and water content (WC) filled in a parallel plate test cell, subjected to high impulse currents. Up-and-down tests are carried out to determine the breakdown voltage, U<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">50,</inf> which gives the corresponding electric field, E<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">50</inf> of a range of soil mixtures. From the obtained results, it is found that the impulse impedance, Z<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">imp</inf>, measured at pre-breakdown level decreases with percentage of EM and WC. E<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">50</inf> and time to breakdown, t<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">D</inf> are lower in soil-EM mixtures than that obtained in soil without EM.