Theory of a field-limiting dielectric

This paper investigates the power frequency properties of a dielectric for which the conductivity is an exponential function of the electric field. Oil-paper constitutes the best known example of such a system. The properties of such a system are revealed through rigorous solution of Poisson´s equation, which facilitates accurate estimates of current and power densities. The analysis indicates that the expression for limiting field determined from circuit theory is approximately correct and that a dielectric with an appropriate exponential dependance of conductivity on electric field might be defect tolerant, i.e., the resistivity could change with field in a manner which would not allow dangerously high fields