Flow-induced electrification and partial discharge measurements in energized transformer duct structures

Physical models which are representative of the materials, construction, and dimensions of power transformer duct structures have been fabricated for both core- and shell-form designs. Electrification characteristics have been documented as a function of the parameters of practical interest and the results obtained have the general character of those found in earlier studies. However, partial discharges have only been detected under worst-case conditions for the blocking structure associated with the shell-form configurations which generate more charge than the corresponding conditions in the core-form construction. The studies have quantified electrification in realistic models characteristic of actual transformers and could be used as a guide to provide estimates of charge levels in energized transformer structures