RESEARCH OF TRANSFORMER MAIN INSULATION DESIGN RULES

Kappeler research performed more than 50 years ago is widely used for HV transformers insulation design. Even though the original experiment was done for oil ducts width from 0.5 to 6 mm, the results have been extrapolated to ducts up to 100 and more mm without detailed publication that would confirm the validity of this extrapolation. This paper presents the experiment that aims to expand Kappeler research to oil duct width up to 30 mm. Model setup also allows creepage and barriers effect testing up to 30 mm