Multifunction Power Quality Monitoring System

In this paper a new power quality monitoring (PQM) system for detection and classification of power quality voltage disturbances is presented. The implementation of the proposed PQM system in a graphical user interface (GUI) is also presented. The wavelet transform (WT) is used for de-noising and detection of the disturbances on power voltage line. Detected disturbances are separated using binary morphology feature extraction and classified according to the PQ disturbances definitions. The classification process is based on the disturbances knowledge base of the expert system. The considered PQ disturbances are: voltage sag, voltage swell, interruption, transient, voltage drop, noise and harmonics. The disturbances characteristics are considered according to IEEE standard 1159 1995. Also other characteristics as RMS value, frequency, time localization, duration and amplitude are considered. The proposed approach was implemented in Matlab and a GUI was created for easily controlling and automating classification of PQ disturbances. The proposed system consists of two GUI windows one for data simulation and acquisition and the second for the de-noising, detection and classification of simulated or acquired PQ disturbances. With the proposed GUI system it is possible to automatically classify simulated and measured PQ disturbances on power voltage line.