Low-cost power quality monitor based on a PC

Abstract

This paper presents the development of a low-cost digital system useful for power quality monitoring and power management. Voltage and current measurements are made through Hall-effect sensors connected to a standard data acquisition board, and the applications were programmed in LabVIEW™, running on Windows in a regular PC. The system acquires data continuously, and stores in files the events that result from anomalies detected in the monitored power system. Several parameters related to power quality and power management can be analyzed through 6 different applications, named: "Scope and THD", "Strip Chart", "Wave Shape", "Sags and Swells", "Classical Values" and "p-q Theory". The acquired information can be visualized in tables and/or in charts. It is also possible to generate reports in HTML format. These reports can be sent directly to a printer, embedded in other software applications, or accessed through the Internet, using a web browser. The potential of the developed system is shown, namely the advantages of virtual instrumentation, regarding to flexibility, cost and performance, in the scope of power quality monitoring and power management.

Power Supply Quality Analysis Using S-Transform and SVM Classifier

“…(d) 4 F is the mean value of TmA-plot. (e) 5 F distinguishes voltage sag and interruption by searching the number of peaks in the time-frequency plot.…”

“…In 1996, Stockwell proposed a better approach called S-Transform (ST), which has a hybrid property of STFT and WT. Not only being immune to noise, but also ST utilizes a variable window length and preserves phase information during the decomposition with the application of the FT kernel [5].…”

Sistema Digital de Bajo Coste para la Monitorización de la Calidad de Energía Eléctrica

“…1, se muestra un diagrama con la arquitectura del sistema desarrollado (Batista et al, 2003). El software del sistema de monitorización ha sido desarrollado entorno de programación gráfi-ca LabVIEW (de la National Instruments).…”

Low-Cost Power Harmonics Analyzer of Nonlinear Loads Based on FPGA

“…Some PQ monitoring systems presented in literature are based on PC [5][6][7][8] where the operative system limits real-time measurements. The remaining works are DSP-PC based systems [9-15] that inevitably depend on a computer for signals acquisition, processing of all captured data or the GUI (Graphical User Interface) development; consequently, being non-standalone instruments.…”

“…Optionally, it sends captured voltage and current signals as well as the magnitude and phase of harmonics through a serial interface RS-232 for detailed analysis or data logging tasks. All these functions are performed on-line and inside a single chip, contrary to cited works in literature [5][6][7][8][9][10][11][12][13][14][15]. Thanks to the low-cost FPGA implementation approach, most of industries can acquire it to analyze in a continuous way their electric facilities, not only for momentary and periodic monitoring due to high cost of commercial products [16].…”