Insulation Performance and Electrical Field Sensitivity Properties of HFO-1336mzz(E)/CO2: A New Eco-friendly Gas Insulating Medium

This paper investigates the AC insulation properties and explores the influence of electric field inhomogeneity on the breakdown voltage of HFO-1336mzz(E)/CO
2
gas mixture. The electrical field sensitivity of HFO-1336mzz(E)/CO
2
and SF
6
is further compared. It is found that the insulation performance of HFO-1336mzz(E)/CO
2
mixture with 25–30% HFO-1336mzz(E) can reach up to 75-85% of SF
6
under the quasi-uniform electric field and there is a favorable positive synergistic effect between HFO-1336mzz(E) and CO
2
. The breakdown voltage of HFO-1336mzz(E)/CO
2
gas mixture demonstrates a “hump” effect with gas pressure under the highly non-uniform electric field and its sensitivity to the electric field inhomogeneity is significantly lower than that of SF
6
. The insulation performance of HFO-1336mzz(E)/CO
2
with HFO-1336mzz(E) content higher than 20% reaches 0.99–1.05 times that of SF
6
under highly non-uniform electric field. The AC breakdown voltage of HFO-1336mzz(E)/CO
2
gas mixture and SF
6
decreases first and then increases with the electric field inhomogeneity (f), demonstrating a “U-shaped” like curve and finally tends to be stable. The related results of this paper systematically reveal the AC insulation properties of HFO-1336mzz(E)/CO
2
gas mixture and provide an important reference for its engineering application.