Methodology for identification of weather sensitive component of electrical load using Empirical Mode Decomposition Technique

Abstract

The expansion planning and operation of all three sectors, generation, transmission and distribution, of power system essentially require load forecasting. Weather conditions have significant impacts on forecasted load, especially short-term and mid-term. A momentous portion of the electrical energy is consumed, especially in cold or hot countries, to mitigate the impact of weather on the daily life of human society. The objective of this thesis is to develop a methodology to identifY the component of electrical demand generated due to the weather. Usually, weather dependent component of load is identified by fitting appropriate non-linear curve to the scatter plot of we~iher- . load model. This technique some times shows lower correlation with weather variables ....,-. .,}. So far, empirical mode decomposition (EMD) technique is used for nOIse suppression of speech signal and biomedical signal processing in the field of Electrical and Electronic Engineering. Electrical load has, to some extent, similarity with speech and biomedical signal. So, like other non-stationary time series signal, electrical load can be decomposed using EMD technique. In this thesis, a methodology has been developed to identifY the weather sensitive component of electrical load using empirical mode decomposition (EMD) technique. In this thesis, EMD technique is used to decompose the load into several components. The characteristic features of each. decomposed component of load are compared with the weather pattern, especially the variation characteristics of temperature and humidity. The characteristics of different combination of different components of load are also compared with that of weather variables. The correlation between load component or that of combination and weather component is evaluated. From the degree of correlation the weather sensitive components of loads is identified. The proposed methodology is applied to the historical load of Bangladesh Power System (BPS). The temperature and humidity data of Bangladesh for the corresponding duration are considered in this process of load decomposition. The proposed methodology is validated by comparing the results obtained through this technique with those obtained using the conventional technique. The accuracy of results is also verified. The developed methodology is applied to the peak loads and the hourly loads of Bangladesh Power System to disintegrate them into weather sensitive portion and nonweather sensitive portion and interesting observations are made.