TC-FLSFCL Provision for Improvement of Distribution System Reliability by TOPSIS based NSGA-II Method

An approach for assignment of the optimal location and tap changer adjustment related to flux-lock type superconducting fault current limiters with tap changer (TC-FLSFCL) is used in this paper by debating the reduction of fault current flowing from each device and enhancement of reliability varying with customer type in a distribution network connected with distribution generation (DG). TC-FLSFCL is a flexible SFCL that it has some preference than previous SFCLs. In this type of SFCL the current limiting characteristics are improved and the fault current limiting level during a fault period can be adjusted by controlling the current in third winding, which also made the magnetic field apply to the high-Tc superconducting (HTSC) element. Three objective functions based on reliability index, reduction of fault current and number of installed TC-FLSFCL is systematized and non-dominated sorting genetic algorithm-II (NSGA-II) style is then formed in searching for best location and tuning of tap changer of TC-FLSFCL to meet the fitness requirements. A decision-making procedure based on technique for order preference by similarity to ideal solution (TOPSIS) is used for finding best compromise solution from the set of Pareto-solutions obtained through NSGA-II. In a distribution network as Bus 4 of Roy Billinton test system (RBTS), comparative analysis of the results obtained from application of the resistive SFCL (RSFCL) and TC-FLSFCL is presented. The results show that optimal placement of TC-FLSFCL than RSFCL can improve reliability index and fault current reduction index with less number