Comparison of real time voltage sag detection based on discrete and continuous wavelet transform in LabVIEW

This paper present the real time voltage sag detection and analysis using discrete and continuous wavelet transform. The real time analysis is carried out in Labview software with the aid of voltage measurement data acquisition module to display the resulting wavelet coefficient corresponding to the acquired voltage signal generated by Chroma Programming. The time delay for the voltage sag detection in both algorithms is evaluated and represent in this paper. The comparison result shows that the implementations of continuous wavelet transform provide better time resolution for the voltage sag event with smaller detection time delay compared to discrete wavelet transform. By using an appropriate data acquisition module and Labview software implementation, execution of continuous wavelet transform in real time voltage sag detection is possible and more accurate especially in electrical system that contains high amount of noise.