A High Accuracy Live-line Calibrator for Current Transformer in power Distribution Network

Abstract

The traditional current transformer calibrator for distribution network does not meet the requirements of live-line calibration due to functional and structural reasons. In order to improve the calibration accuracy and solve the problem of live-line calibration, a high-precision clamp-type current transformer was selected as the standard sensor, and impedance adjustment circuit was applied to realize the compensation of current transformer ratio error and angle error; an innovative AD acquisition and data processing program was used to effectively reduce the error during signal conditioning; the calibrator can directly measure the current signal of the current transformer to realize the live line calibration of the current transformer of the distribution network. The test results show that the accuracy of the current transformer calibrator can reach 0.05% without power interruption, which improves the efficiency of on-site calibrator and reduces the loss caused by the current transformer calibration.