Voltage Distribution Research on Flux-Coupling-Type SFCL

The level of short circuit current in power system is increasing rapidly, and flux-coupling superconducting fault current limiter based on paralleled superconducting windings can effectively limit short-circuit current by the increased impedance after decoupling of the windings. The superconducting winding with high coupling factor is the core component of this SFCL, and the voltage distribution of windings may be uneven depending on the winding type and operating condition. This could affect the quenching of superconducting windings, and even endanger the insulation. In this paper, the voltage distribution of pancake-winding and layer-winding is theoretically analyzed, then simulations considering different operating conditions were carried out, and two prototypes were processed and the experiment results are in accordance with simulation to some degree.