Polyurethane Barrier Surface Tracking Test Results

This paper documents the testing results of the ZR prototype 600-kV mini-Marx trigger generator (MTG) and polyurethane barrier samples from four suppliers. Our goal was to qualify alternative suppliers as future sources of the dielectric interface barriers. The approach was to raise the electric fields on the polyurethane/water interface until surface tracks, or flashovers, occurred and compare the hold-off performance of the different samples. The maximum field stresses exceeded 120 kV/cm. This also provided us the opportunity to evaluate the new MTG packaging and container. One conclusion from this effort is that we did not distinguish any significant differences between the samples, and we can pronounce them all as equally qualified with respect to their electrical performance under these test conditions.