Electric conduction phenomena and carrier mobility behavior in dielectric fluid with dissolved impurities

Electric conduction phenomena and carrier mobility behavior in mineral base electrical insulating oil and various synthetic base dielectric fluids have been investigated in the low voltage region and compared with the data for these fluids containing such impurities as antioxidant, W/0 type surface active agent, etc. It was shown that the carrier mobility of fluids with industrial purity seems to obey Walden´s rule while the fluids with artificial impurities show some ionic conduction behavior and their carrier mobilities seem not necessarily governed by Walden´s rule, depending on the type of the fluids and the impurities. Thus, it would appear advisable that the electrical behavior of the artificial impurities in the dielectric fluids should be dealt with apart from that of the natural impuritiy.