Abstract: When Rogowski coils are used to measure the time-domain waveforms of lightning currents flowing down tall column towers, the coils must have large inside radius and high current capability, then the low-frequency distortion caused in the measurement can be corrected. However, the most commonly used Rogowski coil cannot fulfill all of these. Therefore, this paper presents a large Rogowski coil with a flexible belt-like nonmagnetic core. Large inductance is obtained by increasing the turns of the coil, which makes the coil have self-integrating capability and reduces the difficulty of additional integration. At the mean time, the coil would not work in nonlinear and saturation ranges as the core is nonmagnetic.The calibration results show that this coil has a good self-integrating performanc