Abstract :
Summary form only given, as follows. Electrification, which occurs in transformers due to the entertainment of electrical double layer charge from the recirculatory flow of the oil over internal insulating pressboard surfaces, is simulated in an apparatus consisting of two coaxial cylinders. Pressboard covers these cylinders, while oil fills the gap between them. The inner cylinder is rotated which results in a turbulent flow in the oil region and measurements such as oil charge density, inner to outer open circuit cylinder potential difference, and inner to outer cylinder short circuit current are taken. Comparisons are made between fresh and aged oil for various transient and constant flow rates, temperatures, moisture levels, and applied AC/DC voltage stresses
Keywords :
Couette flow; ageing; flow; short-circuit currents; static electrification; transformer oil; turbulence; Couette flow; aged oil; applied AC/DC voltage stresses; coaxial cylinders; constant flow rate; electrical double layer charge; electrification; inner to outer cylinder short circuit current; inner to outer open circuit cylinder potential difference; internal insulating pressboard surfaces; moisture level; oil charge density; oil filled gap; recirculatory oil flow; transformer oil; transient flow rate; turbulent flow; Aging; Charge measurement; Circuit simulation; Coaxial components; Current measurement; Density measurement; Dielectrics and electrical insulation; Oil insulation; Petroleum; Power transformer insulation;
