Temperature dependent equivalent circuit of a magnetic-shield type SFCL

In order to investigate the reciprocal interaction between a SFCL and the Power System an equivalent circuit of the device needs to be introduced in a power system simulator. In this paper the equivalent circuit of a magnetic shield type SFCL, consisting of two coupled electric and thermal networks, is obtained starting from the integral formulation of the coupled electromagnetic-thermal problem inside the device. The numeric waveforms of current and voltage across an SFCL during a fault are calculated and compared with the experimental ones.