A multifunctional real-time power quality monitoring system using Stockwell transform

The proliferation of power electronic devices in the power sector has intensified the power quality (PQ) issues. Identification of these PQ issues is one of the most important steps for their effective elimination. Hence, development of a real-time (hardware) PQ monitoring system is of great research interest. This study proposes a multifunctional real-time (hardware) PQ monitoring system using Stockwell transform (S-transform). The proposed system is designed and implemented in LabVIEW environment, which can display the real-time fast Fourier transform plots, root-mean-square values, harmonic components, values of total harmonic distortion and three-dimensional plots of S-transform of the three-phase voltages. Main contribution of this study is the real-time detection and classification of different PQ disturbances which even a layman can understand through visual displays to ascertain the quality of supply, unlike other PQ analysers available commercially that require some technical expertise.