Concept for the calibration of the Rogowski coil system of the Wendelstein 7-X stellarator

•Conversion factors of the Rogowski coils at W7-X were calculated from geometry data.•A concept was developed to calibrate the coils for high frequency dampening.•A current source to deliver 1kA at frequencies up to 1kHz is being developed. While the low frequency part of the response of the Rogowski coils mounted in the stellarator Wendelstein 7-X has been calculated, the high frequency part is planned to be calibrated by means of an actively applied current. In a staged approach different conductors have been designed to be mounted inside the plasma vessel and an AC current of 1kA is foreseen to be driven through them at frequencies up to 1kHz to simulate the plasma current.