Numerical Analysis of the Core Dimensions of a Magnetic Fault Current Limiter Assuming a Practical Design and Trial Production

Recently, current suppression devices such as fault current limiters (FCLs) have been required to reduce excessive currents in power distribution lines when the short-circuits occur in the expanding electric power systems, which have high impedance in the fault condition and the low impedance in the normal condition. To realize the required operation, the dc magnetization point of magnetic fault current limiters must be designed to lie in the saturation region under normal conditions. Since a the magnetic FCL is characterized by a dc magnetization point, which depends on the shape of the magnetic core and the magnetic properties, numerical analysis was performed and experimental discussions were held to establish a design procedure for FCLs.