Calibration of Rogowski Coils With an Integrator at High Currents

This paper describes the calibration of Rogowski coils with an integrator for current measurement in the current range of up to 30 kA, at mains frequency. A current loop of ten turns with a current of 3 kA was used for calibration. The magnetic field generated in this way differs from the field of one turn placed at the center and passed with a current of 30 kA. The influence of the unevenness of winding and the cross section of the Rogowski coil may cause a calibration error when using a current loop. The difference in the results between using a current loop and one turn, and the measurement uncertainties are given here. Calculations of the mutual inductances of typical Rogowski coils and their uncertainties are presented in the Appendix.