Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Localized Spectral Analysis of Fluctuating Power Generation from Solar Energy Systems | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2007 Article ID 80919 8 pages doi 2007 80919 Research Article Localized Spectral Analysis of Fluctuating Power Generation from Solar Energy Systems Achim Woyte 1 Ronnie Belmans 2 and Johan Nijs2 3 1 3E sa Rue du Canal 61 1000 Brussels Belgium 2 Departement Elektrotechniek Katholieke Universiteit Leuven KasteelparkArenberg 10 3001 Leuven Belgium 3 Photovoltech sa Grijpenlaan 18 3300 Tienen Belgium Received 27 April 2006 Revised 20 December 2006 Accepted 23 December 2006 Recommended by Alexander Mamishev Fluctuations in solar irradiance are a serious obstacle for the future large-scale application of photovoltaics. Occurring regularly with the passage of clouds they can cause unexpected power variations and introduce voltage dips to the power distribution system. This paper proposes the treatment of such fluctuating time series as realizations of a stochastic locally stationary wavelet process. Its local spectral density can be estimated from empirical data by means of wavelet periodograms. The wavelet approach allows the analysis of the amplitude of fluctuations per characteristic scale hence persistence of the fluctuation. Furthermore conclusions can be drawn on the frequency of occurrence of fluctuations of different scale. This localized spectral analysis was applied to empirical data of two successive years. The approach is especially useful for network planning and load management of power distribution systems containing a high density of photovoltaic generation units. Copyright 2007 Achim Woyte et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. INTRODUCTION Most applications of wavelet decomposition in the field of electrical power engineering concern the analysis of load profiles 1 2 the electrical
