Evaluation of commercial current transformer comparator by using precise standard capacitors and resistors

We have developed a method for calibrating both ratio error and phase displacement of current transformer (CT) comparator by using the precise standard capacitors and resistors. The calibration method was applied to commercial CT comparator under test. The calibration points cover the ratio error range of 0 ~ ±10 % and phase displacement ranges of 0 ~ ±7.5 crad. We can evaluate CT comparator by comparing the calculated errors with the measured errors. Finally we have estimated uncertainty of our method.