Real-time implementation of wavelet transforms for electrical power quality applications

This paper presents a real-time implementation of wavelet transforms for detection and analysis of power quality disturbances in power systems. The paper describes the method used for the implementation of the discrete or packet wavelet transforms in a virtual measurement instrument. The system developed allows the selection of the mother wavelet, the sampling frequency and the decomposition tree to be used for the analysis. Depending on the type of power quality disturbance to be analyzed and the frequency band of interest, a partial wavelet decomposition tree can be implemented, improving the performance of the method proposed and enabling its use as a protection scheme in power systems.