Time-Domain Analysis of Protection Systems - Assessing the Behavior of Overcurrent Function of Harmonic Filters During Energizations

This paper evaluates the behavior of harmonic filters subjected to overcurrents during energization. Statistical studies were carried out in ATPDraw considering different techniques to estimate the magnitude of inrush currents, one based on a true RMS estimator and another based on a 60-Hz Fourier filter phasor estimator. The results show that the theoretical limits of the currents used as reference to the overcurrent protection settings presented in literature were consistently defined in the evaluated cases, but that the selection of the decay time could be improved.