Measurement of the Current in 2G HTS Coil With Rogowski Coil in Cryogenic Environment

This paper presents a Rogowski coil that can be used to measure the current in second-generation (2G) high-temperature superconducting (HTS) coils in a cryogenic environments. We describe the key materials involved in building the coil and its structure and then report on experiments that were carried out to assess its potential. To ensure the accuracy of current measurements in cryogenic temperatures, the coil was given a closed and rigid shape and foamed plastic was used to fix a 2G HTS wire in the center of the coil. Silicon nitride ceramic was chosen to build the winding holder because of its thermodynamic stability and mechanical strength in cryogenic environments. The performance of the Rogowski coil was evaluated in a liquid nitrogen bath at 77 K. The results confirmed the stability of the coil and the accuracy of its current measurements, underscoring its viability for 2G HTS applications.