A Contribution for Characterizing Measured Three-Phase Unbalanced Voltage Sags Algorithm

This paper addresses the problem of characterizing voltage sags from measured three-phase voltages. A new algorithm based on three-phase voltage magnitudes and their phase angles is proposed in this paper. This new algorithm is named the three- phase three-angle algorithm (TP-TA). The proposed algorithm is compared with the well known symmetrical component (S-C) and the six-phase (S-P) algorithms defined to identify voltage sags type C and D. Numerical examples and recorded voltages were used to validate the proposed algorithm and compared with the other two, yielding better results for the TP-TA algorithm.