Analysis of current loads arresters installed at towers of overhead lines

摘要

Laws of the distribution of amplitudes of lightning currents broken through in wires of overhead lines (OL) under a direct lightning stroke in a system 《wire-ropes-ground》 are obtained. It is shown that both mathematical expectation of lightning current surge amplitudes and their square deviations are reduced approximately twice with account taken of the lightning leader channel orientation. That made it possible to obtain nonoverstated evaluations of current loads in arresters and values of energy absorbed in completing varistors. So, the current loads in arresters installed at towers OL 330-750 kV of various constructions accounted 25-50 kV (without taking into account lightning leader channel orientation 65-75 kA).