An Adaptive mimic filter — Based algorithm for the detections of CT saturations

An adaptive mimic filter-based algorithm for detecting the saturation of current transformers (CTs) has been presented and implemented in this paper. First, an adaptive method was developed for obtaining the line impedance of a digital mimic filter. The variations of the obtained line impedance were then used to detect the CT saturations. By using the proposed algorithm, the saturation period of a current waveform can be accurately detected. This paper finally utilized the MATLAB/SIMULINK software and a DSP-based environment to verify the proposed algorithm. Test results show the proposed algorithm can accurately detect the CT saturations.