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We reported the fabrication and analysis of the reactor for matrix-type superconducting fault current limiters (SFCLs). Reactors take a role of inducting magnetic field to superconductors in reactors and bypassing partial fault currents to themselves. Superconductors used in this work were YBCO thin films deposited on 5.08 cm diameter Al 2 O 3 substrates. Also, reactors with a diameter of 90 mm and a length of 230 mm were fabricated. Then, we constructed the matrix-type SFCLs with a reactor which consists of a trigger part and current limiting parts. Experimental results are reported in terms of the characteristics of fault current in superconductors and reactors, and distribution of the fault power between them.

In this work, we report the recovery characteristics of matrix-type superconducting fault current limiters (MFCL). To do this, we constructed three-phase MFCLs with 1 × 3 structures by using 9 superconducting elements. Also we constructed resistive-type SFCL without a reactor for inducing magnetic field for the purpose of comparison. Superconductors used in this work were YBCO thin film deposited on 2 inch diameter sapphire substrates. It was etched in meander line in order to achieve sufficient resistance when a fault occurs. Resistive-type SFCLs used the same superconductors of MFCLs and all experiments for both SFCLs were performed under the same experimental condition. We confirmed that recovery characteristics of MFCL were shorter and more balanced than those of resistive-type SFCLs under diverse experimental conditions.

We analysed the characteristics of the single, double and triple lines-to-ground fault of matrix type SFCLs (MFCL) with reactors for magnetic field. We compared characteristics of our MFCLs with those of resistive type SFCLs without reactors under the same experimental conditions. The magnitude of a limited fault current of MFCLs with a reactor according to fault voltages showed similar patterns directly after a fault. Also, the current limiting characteristics of MFCLs according to turn numbers of reactors showed similar patterns directly after a fault. However, the limitation of fault currents after 3 cycles showed a tendency to increase with increasing applying voltages. Our MFCLs had balanced patterns of limited currents between the R, S, and T phases. However unbalanced patterns of limited currents were observed in case of resistive-type SFCLs. It was because of unbalanced quenches between superconducting elements in resistive-type SFCLs and each phase. We reported the experimental results in terms of the properties of quenches, patterns of limited currents and limited voltages in the R, S and T phase systems.