The Statistical Distribution of Values of Breakdown Voltage for An Air Gap

摘要

An analysis of 30,000 measurements of breakdown voltage on a spark gap removed from a surge diverter shows there to be a linear relation between normal probability and the logarithm of the excess of the applied voltage over a critical voltage. This linearity extended over more than six standard deviations. A statisticcal model is derived which agrees well with the experimental findings and which is investigated further to show that the physical parameter of the breakdown process in air which controls the scatter of test results is the rate of change of the first Townsend coefficient with field.