Engineering method for high-voltage substations lightning performance estimation

A computer method for estimating the lightning performance of high-voltage substations is developed and modified for simple engineering applications in the substation design. The main substation element representation and the equivalent circuit choice are suggested. The method is illustrated by the example of a 110 kV substation with a cable entrance. Both shielding failures and lightning strikes to the towers or the earth wires, causing back-flashovers on the incoming overhead lines, are analysed and the best variant of the overvoltage protection suggested.