Sensitivity Analysis of Breakdown Voltage Calculations for Liquid Nitrogen

Liquid nitrogen is applicable as coolant and insulation for high-temperature superconductors and offers a more economical alternative to liquid helium. For failure prevention, knowledge of the electrical withstand capability is required, which can be acquired through experiments. These experiments showed that there are a lot of influence factors on the breakdown voltage. Experiments conducted at this institute, covering some of these influences, have been already presented in several other works. These experiments, combined with the available scientific literature, led to the evolution of practically oriented formulas to calculate the breakdown voltage in liquid nitrogen with and without gas bubbles. In this paper, the evolution of the aforementioned formulas is presented in addition to an explanation of their respective background. Furthermore, possible influences on the breakdown voltage found in the formulas are emphasized. Then, the degree of effect that these influences have on the calculated breakdown voltages is calculated and presented. Finally, a ranking of these parameters is given, as assistance to check experimental conditions and to evaluate theoretical results.