Abstract
Evaluation system for calibrating Rogowski coiI(RC) up to primary current of 40,000 A have been established. The system consists of 40,000 A AC high current source, current transformer(CT) comparator, standard CT, RC under test, voltage to current convertor(VCC), buffer and CT burden. An AC high current is applied to the primary windings of both the standard CT and the RC under test, and then the CT comparator measures the ratio error and the phase displacement by comparing the secondary current of the standard CT with output current of VCC. For testing of RC, we have evaluated two RCs under test of primary current ranges of 0 A ${\sim}$ 2,000 A and 0 A ${\sim}$ 40,000 A with the accuracy class of 1 %. The extended uncertainty is 0.02 % ${\sim}$ 0.23 % for ratio error and 0.29 min ${\sim}$ 1.93 min for phase displacement in the primary current ranges of 10 ${\sim}$ 40,000 A.
