Creeping discharge at vegetable-based oil/pressboard interface under rectangular impulse voltage

The behavior of creeping streamer propagating the pressboard surface in vegetable-based oils; PFAE (palm fatty acid ester) oil and CRS (crude rapeseed) oil was studied under the applied rectangular-impulse voltage. The discharge shape, streamer length, discharge current and discharge light have been measured as a function of the voltage and its pulse width. These characteristics are compared with those in mineral oil.