Fluorocarbon liquid dielectric at DC-stresses

Abstract

Preliminary results of studies of DC action on some perfluorocarbon liquids show that these liquids have low conductivity under strong field, sufficiently high electric strength, and the possibility of electric field measurement using a simple electrooptic technique. Other features such as non-flammability and non-toxicity give additional advantages in the application of perfluorocarbon liquids as liquid electric insulation in electrotechnical devices. Specifically, results are presented on the I-V dependence and electric field measurement for perfluoro-3-ethylamine. Electric field was measured by the Kerr effect in a system including a laser, a modulator, a cell between cross polarizers, and a photomultiplier. The linear dependence of the photocurrent square root on the squared voltage in a wide range makes it possible to determine the Kerr constant for liquid dielectric and to draw a conclusion about insignificant distortion of electric field due to space charge.<>