Výpočet zkratových proudů v trojfázových střídavých soustavách dle EN 60909

Abstract

This bachelor work deals with short-circuit currents in three-phase electric systems, where in the first part are, with which short-circuit failures we may encounter and which impedance components to be calculated, we to attain acceptable results. The second part describes the methods and rules for the calculation of short-circuit currents by valid standard ČSN EN 60909. In the third and fourth part we present calculations of the parameters of the components and examples of calculations of short-circuit currents. In the final section provides a practical calculation short-circuit ratios for VN system an industrial enterprise. The methods used for calculation are symmetrical components and sequential simplification.