Modeling of the transient behavior of a resistive type high Tc fault current limiter

The potential distribution in electrical equipment during transient excitation is an important criterion for the design of the insulation. Transients in electric power networks can be caused by lightning strikes, disconnecting operations or system disturbances. In this work the transient behavior of a resistive superconducting fault current limiter (SFCL) based on Bi-2212 tubes, which are connected in series, has been modeled. The SFCL will be used in a 10 kV bus tie of a German utility. A lumped network model of the limiter has been developed and implemented in PSpice to investigate the transient behavior. The model includes inductive- and capacitive coupling, respectively. An AC analysis is performed to obtain the frequencies which will cause the highest overvoltages between the windings of the limiter. Furthermore a lightning impulse voltage and a lightning stroke current are applied to the limiter to investigate its transient behavior. A simplification of the model is performed to reduce the computing time. Both models are compared and a good agreement of the results is obtained.