A Study of a New Lightning Progression Model

Abstract

Lightning is one of the most important reasons for proper insulation design of power transmission apparatus. It has been known that lightning progression features in winter and summer seasons differ in the occurrence process and a scale and so on. There are unknown lightning parameters though a lot of records of lightning observation were obtained up to this time.
This report deals with a new lightning progression model and the estimation methods of the various parameters of the lightning phenomena quantitatively based on the data of long gap tests and lightning observations. The new progression model is applicable to not only winter lightning but also summer lightning, and the values of various parameters such as the charge density of a stepped leader, the leader development velocity, the time interval between steps, the time-to-discharge of first stroke, the final striking distance and so on are estimated by a new calculation method. The new model is useful for a computer simulation of lightning progression and development of a new lightning shielding theory.