Suggesting A New Method For Reaching An Ppropriate Passive Filter Design For Harmonic Reduction Based On Wavelet Transform
Regarding the increasing importance ofpower electronicdevices application in industry and different harmonic problems, this research aims to present a new method based on wavelet transform, through which passive filters for harmonicreduction is designed.Furthermore, as a representation for harmonic sources, HVDC system, which has many applications in industry, is chosen. Despiteother researches which have been done for harmonic detection, this time we know that 3rd,5th, 7th, 11th, 13th and 24th (as a high orderharmonic) harmonics exist.But it is tried to use harmonic detection for reducing them through appropriate passive filter design. Finally, we show that the proposed method works better thantraditional methods for passive filter design due to simplicity, and the capability of combining wavelet transform with computational methods. Results show that the proposed method can significantly reduce harmonics in several steps throughdecomposing a signal into its components. Also using a scalogram of signals before and after final passive filter design, confirms the authenticity of this method.
Index Terms- Multi-Resolution, Decomposition, Passive Filter for Harmonic Reduction, HarmonicDetection, Wavelet Transform, HVDC System