ELECTRIC CONDUCTION PHENOMENA ANDCARRIER MOBILITY BEHAVIOR INDIELECTRIC FLUIDS

Electricconductionphenomena and carrier mobility behaviorin mineralbase electricalinsulatingoil and various kinds of syntheticbase dielectricfluids have been investigatedin the low voltage region and have been compared with our results in these fluids containingvarious kinds of oil-solubleimpurities. It was shown that the impuritiesbring about some ionic conductionin the fluids, and that the carrier mobilitiesof the fluids containingthe impurities not necessarily seem to be governed by Walden's rule, dependingon the types of the fluids and the impurities. In contrast, the fluids with industrialpurities obey the rule. Furthermore,it was suggested that an electric conductionmechanismin the fluids containing the impuritiesseems to be closely related to a carrier mobility mechanism in these fluids. Thus, it appears advisablethat the electricalbehavior of the artificialimpuritiesdissolved in the dielectricfluids shouldbe dealt with apart from that of the natural impurities.