Wavelet representation of voltage flicker |
| |
Affiliation: | 1. Department of Transplantation, Mayo Clinic, Jacksonville, FL 32224, USA;2. Florida State University, Tallahassee, FL 32306, USA;3. Department of Molecular and Translational Medicine, University of Brescia, Brescia 25133, Italy;4. Department of Nanomedicine, Houston Methodist Research Institute, Houston, TX 77030, USA;5. Department of Medicine, Weill Cornell Medicine, New York, NY 10065, USA;6. Department of Cancer Biology, Mayo Clinic, Jacksonville, FL 32224, USA;7. Division of Hematology/Oncology, Mayo Clinic Cancer Center, Mayo Clinic Florida, Jacksonville, FL 32224, USA;8. Department of Physiology and Biomedical Engineering, Mayo Clinic, Jacksonville, FL 32224, USA |
| |
Abstract: | Voltage flicker can be considered as a voltage magnitude modulated signal with a frequency ranging from 0.5 to 30 Hz. Wavelet transform is a powerful tool to analyze this kind of nonstationary, wide-range frequency signal. The wavelet representation of voltage flicker signal is presented in this paper. The proposed scheme is implemented in three steps. Firstly, a low-pass demodulation filter is designed to find the magnitude of 60 Hz component. Accordingly, a high degree of accuracy may be achieved and the effect of the transient, harmonics and white noise may be eliminated. Secondly, a multiresolution analysis (MRA) scheme that is an orthonormal wavelet transform, can then be applied to decompose the demodulated signal into several components according to the scales. Components at high scale can be considered as white noise, while components at the low scale represent the voltage fluctuation. The smooth version left by the MRA scheme represents the DC component. Finally, the voltage flicker level can be estimated by the wavelet coefficients at different scales, which give the time and frequency information. Numerical examples are also presented in this paper to show the efficiency of the proposed scheme. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|