Research and application of electric power signal filter based on wavelet multi-resolution technology

In signal collection process, useful signal usually mixes noise interference such as white noise, which usually causing error in computer analyzing and processing. At present, normal de-noising method includes hardware and software. This paper uses wavelet transformation software method, which realizing noise de-noising to electronic power signal. In wavelet analysis, suitable of threshold function selection defines signal de-noising effect directly. This paper adopts Matlab simulation, carrying out serial kinds of different wavelet basis selection, and adopting different threshold function, which getting different signal de-noising effect. This paper uses db24 wavelet and adopt heursure rule to complete electronic power signal´s decomposition and reconstruction by Matlab software. From simulation we can see, wavelet filter and de-noising method is superior to other method in some non-stable signal process.