Using high-temperature superconducting tapes to improve the generation of high-voltage pulses

Abstract
This paper explores the integration of high-temperature superconducting tapes to improve the performance of Vector Inversion Generators (VIG), a family of compact and lightweight high-voltage pulse generators. In this work, our existing theoretical model of Vector Inversion Generators is updated to capture the impact of AC losses associated with superconducting tapes. Then, a first-ever experimental campaign on superconducting VIGs is conducted. The results confirm a voltage boost enabled by High-Temperature Superconducting (HTS) tapes, provided the substrate is non-ferromagnetic. Based on the validated model, the performance of VIGs with longer HTS tapes is projected, revealing that the boost in VIG performance achieved by reducing losses resulting from the use of superconducting material is more pronounced when the tape length is increased. Nevertheless, the use of superconducting tapes to improve the performance of VIGs is inherently limited in input voltage because of the non-linear behaviour of AC losses, which can cause the losses associated with HTS tapes to become higher than the ohmic losses of copper tapes. As a consequence, to improve the performance of VIGs for increased values of input voltage, one can either use HTS tapes with higher critical currents, use methods to reduce AC losses - such as filamentisation or striation of coated conductors -, or investigate other methods to enhance VIG performances, such as lower inductance switch designs.