The Development of active capacitive voltage divider based on current transformer with compensation circuit

Abstract

In order to solve the test of the frequency response characteristics of the DC voltage divider, this paper proposed an active voltage divider based on an electronically compensated current transformer. By setting different current transformer primary and secondary turns ratios, the voltage divider ratio could be changed. Through the three-winding design on a single iron core, the active compensation of the current transformer is realized and the linearity of the current transformer is improved obviously. The notch circuit is used to improve the measurement accuracy of the secondary current sampling circuit of the current transformer. Tests indicates that the voltage divider ratio varies with frequency not more than 20ppm, and phase shift is not more than 200μrad within 2500Hz.