Study of electrical and rheological properties of natural and other oils

This paper deals with the analysis of promising environmentally compatible electrical insulating fluids for electrical engineering. It starts with the overview of the current state of the art and of the latest trends in the use of biodegradable natural oils. In the experimental part, castor oil, linseed oil, sunflower oil and rapeseed oil as well as their components, fatty acid esters, were studied. Dielectric properties were measured using precision LRC meters Agilent 4284A and 4980A including dielectric liquid test fixture Agilent 16452A. Also, Agilent graphical language environment VEE Pro was used for the communication between a PC and Agilent analyzers. Electrical properties of the above-mentioned oils are presented in the frequency domain in the 20 Hz - 1 MHz in the temperature interval 283 K - 363 K; also shown are rheological properties in the 293 K - 363 K temperature range.