The AC breakdown voltage measurement of an evaporative coolant under two-phase-flow condition and its statistical analysis with weibull distribution and normal distribution

As some fluorocarbons have the nonflammability and high electrical strength, they could be used not only as coolant, but also as insulating materials. In order to obtain the AC breakdown voltage of some fluorocarbons under two-phase- flow condition, special experimental equipment was designed and fabricated. Using a plane-plane electrode with a gap length of 3 mm, the test was carried out and the result was analyzed statistically. The analysis demonstrated that both the Weibull and Normal distribution match the result quite well. The more the data samples are, the better the statistical distributions will match. Under the condition of a small quantity of samples, it´s better to prefer Normal distribution because of the less error it has. Meanwhile, the Weibull distribution matches the sample better under the circumstances of a large quantity of samples.