Abstract：The kA level wideband AC high current calibration system is introduced to stress the calibration of AC high current with a maximum range of 2 kA and frequency of 50 Hz~1 kHz. To ensure the integrity of the AC high current traceability chain, the calibration method of compensated AC current ratio standard has been studied. A set of AC current ratio calibration devices that can cover ratios up to 1000:1 and frequencies up to 1 kHz has been developed, solving the key issue of non-power frequency current ratio standard traceability. Related tests have been conducted to verify the reliability of the quantity transmission of the AC current ratio self-calibration system. Through the establishment of wideband AC high current calibration system, calibration experiments were conducted on the tested AC high current source. It was verified that the expanded uncertainty of the system is about 2.4×10-4, which could meet the calibration requirements of most wideband AC high current devices.
2025, Vol. 46 
