Surge phenomena on non-homogeneous transmission line and parameters of transformer for the interconnection.

The paper deals with surge phenomena on transmission lines consisting of two parts overhead line and cable. The case of the overhead line supplied by the voltage source and connected to the cable via the transformer is considered. The parameters of transformer for the interconnection were found by comparing of used calculation method with results of measurements. This transformer with such defined parameters is integrated for solution of the whole problem. The load of cable line can be modelled by resistance, capacitance, inductance or any combination of them. The propagation of surge wave caused by the lightning stroke along the overhead line in any point is observed. The problem of distance between the position of the transformer and the point of lightning stroke is investigated and is solved numerically in the time domain. The efficiency and correctness of the used method is shown by an illustrative example.