Correction of saturated current from measurement current transformer

Abstract

The suggested study presents an easy and effective way to compensate for the distorted secondary current of measurement-type current transformers (CTs). The suggested compensating algorithm is based on estimating the magnetising current from a Fröhlich hysteresis approach. The efficiency of the proposed technique was first proved using computer simulations. The prototype compensating device was then tested in a laboratory environment using a 5/1A, 10VA, C0,5 measurement-type CT. The proposed compensation algorithm is dependent on CT burden and X/R ratio of the line where CT is connected. The outcomes of the study demonstrate that the technique is able to reconstruct the secondary current with an acceptable error and can be applied to any measurement-type CT regardless of its size and winding topology. © The Institution of Engineering and Technology 2013.