Using Hybrid Type SFCL to Limit the Surge Current Caused by Closing Loop Operation in Distribution System

Abstract

Owing to the scale of power distribution system’s continuously expanding, the closing loop operation is usually needed to meet the demand for the reliability of power supply. However, during the course of this operation, a larger AC surge current with 4~5 times of normal value will be induced, and the surge current can cause the equipped over-current protection take action incorrectly. In this paper, a hybrid type superconducting fault current limiter (SFCL) is suggested to installing into the distribution system, which will take action to inhibit the closing-loop transient surge current by using current-limiting impedance during the transient process. Furthermore, the simulation model of a typical distribution network with the hybrid type SFCL is built through PSCAD/EMTDC software. From the simulation results, it is verified that the suggested hybrid type SFCL can obviously reduce the surge current and improve the power system’s operational stability.