Relation between pulse generating phase and that of the adjacent pulse at tree discharge

Time series data of typical tree type discharges are analyzed from the viewpoint of whether a discharge pulse phase affects the next discharge pulse phase. Contrary to an expectation from the Whitehead model, there seem to be no mutual relationship between a pulse phase and the next pulse phase. On the other hand, the average phase of a discharge pulse group in a half cycle has a slight tendency to affect that in the next half cycle. The time series information of practical tree discharges are analyzed by using test data of a 66-kV cross-linked polyethylene cable with an artificial defect.