Design criteria for experiments to measure the breakdown voltage of insulating gases in uniform electric fields

Round robin breakdown experiments in (quasi)uniform electric fields have been performed in 7 different laboratories for air, HFO1234ze(E)/N2 (20 %/80 %), and SF6 as example gases. The experiments are supported and discussed with an extended literature review of gas-physical phenomena and constructional setup parameters influencing the results. The goals are to investigate a) the influence of certain experimental parameters on the outcome and scatter of breakdown measurements and b) to define suitable and practical setups for breakdown experiments and evaluation methods for the main experiments of Cigré working group D1.67 investigating new non-SF6 insulating gases and gas mixtures. The final recommendation is to use polished plane-plane Rogowski electrodes with a spacing of 5 mm in a self-supporting PEEK frame, and an AC voltage rate of rise around 0.1 kV/s. The value of this study goes beyond the work of the working group D1.67 and serves as basic recommendation for all groups performing breakdown experiments in gaseous insulation systems.