Visual investigation of prebreakdown point charge injection into N-hexane by new electrooptical measuring system

New original method and experimental technique for visualisation and optical measurements of two-demensional conductivity distribution in dielectrics under high voltage pulses had been developed. Charge and current sensitivities about 10^-14 C and 10^-12 A respectivly had been obtained. As a result of our development and investigations the existence of prebreakdown point charge injection was established. Obvious connection of discovered injection phenomena with pulse electrical breakdown of nonpolar dielectric liquids was found. General behaviour of point charge injection being observed is seemed to be due to adsorbtion of unimpurities on electrode surfaces. This conclusion is confirmed by evident dependance of point charge injection level from purification degree of studed liquids.