Influence of fault type on the optimal location of superconducting fault current limiter in electrical power grid

Abstract

This paper presents a novel approach to determine the optimal location of a resistive superconducting fault current limiter (SFCL) to improve the transient stability of an electric power grid (EPG). The presented method use the angular separation of the rotors of synchronous machines present in the power system to select the optimal location of SFCL. The selection of this optimal location is coordinated with the corresponding optimal resistive value to improve transient stability in case of short-circuit fault. To obtain a global study on the optimal placement of SFCL in case of fault, various types of short-circuits are considered (single phase grounded fault, two phases grounded fault, etc.). To evaluate the effectiveness of the proposed method, the IEEE benchmarked four-machine two-area test system is used to carry out several case studies. It is shown that the optimal location of SFCL as well as its optimal resistance value are not the same for each fault studied. A global analysis of EPG stability is presented in the paper to select only one location of the SFCL in the EPG. Results show that the optimal location of SFCL combined with its optimal resistive value reduces the angular separation of the rotors that improves effectively the stability of the EPG for any type of short-circuit.