EFFECT OF WATER CONDUCTIVITY ON ITS PULSE ELECTRIC STRENGTH - Electrical Insulation, 1996., Conference Record of the 1996 IEEE International Symposium on

The dependence of the impulse electrical strength of water on conductivity was investigated in non-uniform electric field point-plate electrode system. The voltage pulses, with the rise time t,=l ps, and time to half-decay tuz= 30 ps, were generated by a Marx bank. Conductivity was varied by the use of different CuSO4 concentrations in distilled water. The voltage and current during the electrical breakdown were recorded by using a pulse voltage divider and current shunt. The dynamic resistance calculated from current and voltage waveforms during electrical breakdown, is also presented. On the basis of these waveforms, the dependencies of the time to breakdown and breakdown voltage on the conductivity for two polarizations of the point electrode are plotted. Investigations made by means of static photography were carried out. It was found that the electrical strength of water depends strongly on the polarity of point electrode and the conductivity of the water. The electrical strength of water decreases, and time to breakdown increases, as water conductivity is increased.