Performance Improvement of a Measurement Station for Superconducting Cable Test

A fully digital system, improving measurements flexibility, integrator drift, and current control of superconducting transformers for cable test, is proposed. The system is based on a high-performance integration of Rogowski coil signal and a flexible direct control of the current into the secondary windings. This allows state-of-the-art performance to be overcome by means of out-of-the-shelf components: on a full-scale of 32 kA, current measurement resolution of 1 A, stability below 0.25 Amin-1, and controller ripple less than 50 ppm. The system effectiveness has been demonstrated experimentally on the superconducting transformer of the Facility for the Research of Superconducting Cables at the European Organization for Nuclear Research (CERN).