Document Type : Research Article
In this paper, the impacts of installing superconducting fault current limiter (SFCL)in radial and loop power distribution system are evaluated to improve voltage sag in both cases of with and without distributed generations (DG). Among various SFCLs, the hybrid type with a superconducting element in parallel with a current limiting reactor (CLR) is selected. This is more effective than resistor-type SFCLs because it reduces the burden on the superconducting element, ac losses and cost in distribution system. According to SFCLs impedance and their locations in power system, voltage sag will be improved by reducing the fault current. In this paper, SFCLs with various arrangement and CLR magnitudes are installed in distribution system and improving the voltage sags on different buses are examined according to fault position. Area of severity (AOS) method and expected annual sag frequency (ESF) are used to analyze the voltage sag. The results show that installing SFCL can improve the voltage sags as well as fault current reduction in radial and loop distribution systems.