Combined temporary overvoltages due to single-pole short-circuit and Ferranti effect

Abstract

The paper presents the determination of combined temporary overvoltages that appear on healthy phases of long unloaded lines in the event of a single-pole short circuit. For this purpose, theoretical foundations are presented, based on the quasi-static treatment of the problem and the application of symmetrical components, in which original analytical expressions for determining the corresponding coefficients of combined temporary overvoltages are derived. Using these coefficients, the amplitudes of the mentioned combined temporary overvoltages are then very simply calculated. All of the above is also demonstrated on a selected representative example of a transmission line.

Petar Sarajčev

Full Professor | Department of Power Grids and Substations