Influence of burden of current transformer (IEC Standard) on the high frequency current measurement

This paper presents the influence of burdens on the accuracy of current transformer (CT) at wide frequency range. Various types of burdens are used in this investigation. Analysis of the experiment results show that if the value of burden is fixed at 50 Hz in the calculation, the ratio error of CT is practically within the limits of IEC standard, only at 50 Hz. Unfortunately, the ratio errors increase drastically with increasing frequency in this case. If the value of burden is changed with frequency in the calculation, the ratio error is acceptable for all frequency up to 1 kHz. The resistive burden is also investigated. The results show that the ratio error of CT is practically in accordance with IEC standard, if and only if there are insignificant impedance of wire between the CT and the measuring device.