Short Circuit Current Analysis of Additional Load on Common Auxiliaries Bus of Nuclear Power Plants using ETAP

This paper presents an evaluation of a case study for load flow and short circuit analysis of a 5 MWe load addition to a nuclear power plant’s common auxiliaries’ bus. The purpose of this study is to especially simulate the behaviour of short-circuit current and find its magnitude with and without the proposed additional load connection. The simulation is carried out using the electrical transient analyzer program (ETAP). Load flow results show that the busbar voltage is reduced from 97.03% to 95.89% due to the proposed additional load connection. The short circuit current is increased from 42.8988 kA to 45.2396 kA due to the proposed additional load connection. That is very close to the rated short circuit capacity (50 kA) of circuit breakers. Which may compromise the design margin.