I. Introduction
Research into pulsed electrical breakdown in liquid applies to many fields including energy storage [1], [2], high-voltage switching [3], [4], and high-voltage insulation [5]. Notably, polar liquids have large dielectric constants and high dielectric strength [6], [7], which allow temporary electrical energy storage at high energy densities. Measurements of the dielectric strength (breakdown voltage) of polar liquids have focused on water [8] and mixtures of water with glycol [5]. For water, particularly, an empirical equation for the electrical breakdown field, which takes the pulse duration and the electrode area into account was established by Martin [9] \begin{equation*}F_{\pm}=\alpha K_{\pm}A^{n\pm}\tau^{-1/3}\tag{1}\end{equation*} where is the breakdown field in MV/cm, is a constant related to the electrode geometry, is the electrode area in cm 2, within 90% of the peak electric field. and are polarity con-stants, given by , and . in microseconds is the effective time and is defined as the duration for which the voltage reaches 63 % of its maximum value. It was found this formula can hold for pulse durations down to 200 ns when the pin electrode is cathode. However, when the pin electrode is an anode, Martin's formula needs to be adjusted for the values of the polarity constants (from 0.23 to 0.34) and (from −0.058 to −0.09) [10]. For a point-plane electrode configuration, where the point electrode area is not a significant factor, was found to have a dependence [11].