000000016 001__ 16
000000016 037__ $$aENY-ARTICLE-2008-014
000000016 041__ $$aeng
000000016 088__ $$aRZ I07/04/I-008
000000016 100__ $$aLobos, T$$uWroclaw University of Technology, Poland
000000016 245__ $$aTime-frequency analysis of non-stationary signals in power systems
000000016 260__ $$c2005-01-29
000000016 300__ $$a4p
000000016 500__ $$aEighth IEE International Conference on Developments in Power System Protection. Amsterdam, 5-8 April 2004. Vol. 1. London: IEE 2004 pp. 68-71
000000016 520__ $$aRepresentation of signals in time and frequency domain has been of interest in signal processing areas for many years, especially taking in the limelight time-varying non-stationary signals. The standard method for study time-varying signals is short-time Fourier transform (STFT) that is based on the assumption that for a shorttime basis signal can he considered as stationary. The spectrogram utilizes a short-time window whose length is chosen so that over the length of the window signal is stationary. Then, the Fourier transform of this windowed signal is calculated to obtain the energy distribution along the frequency direction at the time corresponding to the canter of the window. The crucial drawback of this method is that the length of the window is related to the frequency resolution. Increasing the window length leads to improving frequency resolution hut it means that the nonstationarities occumng during this interval will he smeared in time and frequency. This inherent relationship between time and frequency resolution becomes more important when one is dealing with signals whose frequency content is changing rapidly, Baraniuk (l),Choi and Williams (2).
000000016 700__ $$aRezmer, J$$uWroclaw University of Technology, Poland
000000016 700__ $$aSikorski, T$$uWroclaw University of Technology, Poland
000000016 700__ $$aSchegner, P$$uTechnical University of Dresden, Germany
000000016 8560_ $$fzbigniew.leonowicz@pwr.wroc.pl
000000016 8564_ $$uhttp://zet10.ipee.pwr.wroc.pl/record/16/files/$$zAccess to Fulltext
000000016 909CO $$ooai:zet10.pwr.wroc.pl:16$$pglobal
000000016 980__ $$aARTICLE