EM - Escola de Minas
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6
Notícias
A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.
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3 resultados
Resultados da Pesquisa
Item A self-adaptive evolutionary fuzzy model for load forecasting problems on smart grid environment.(2016) Coelho, Vitor Nazário; Coelho, Igor Machado; Coelho, Bruno Nazário; Reis, Agnaldo José da Rocha; Enayatifar, Rasul; Souza, Marcone Jamilson Freitas; Guimarães, Frederico GadelhaThe importance of load forecasting has been increasing lately and improving the use of energy resources remains a great challenge. The amount of data collected from Microgrid (MG) systems is growing while systems are becoming more sensitive, depending on small changes in the daily routine. The need for flexible and adaptive models has been increased for dealing with these problems. In this paper, a novel hybrid evolutionary fuzzy model with parameter optimization is proposed. Since finding optimal values for the fuzzy rules and weights is a highly combinatorial task, the parameter optimization of the model is tackled by a bio-inspired optimizer, so-called GES, which stems from a combination between two heuristic approaches, namely the Evolution Strategies and the GRASP procedure. Real data from electric utilities extracted from the literature are used to validate the proposed methodology. Computational results show that the proposed framework is suitable for short-term forecasting over microgrids and large-grids, being able to accurately predict data in short computational time. Compared to other hybrid model from the literature, our hybrid metaheuristic model obtained better forecasts for load forecasting in aMG scenario, reporting solutions with low variability of its forecasting errors.Item NeuroDem - a neural network based short term demand forecaster.(2001) Silva, Alexandre Pinto Alves da; Rodrigues, Ubiratan de Paula; Reis, Agnaldo José da Rocha; Moulin, Luciano SouzaThe application of Neural Network (NN) based Short-Term Load Forecasting (STLF) has developed to sophisticated practical systems over the years. However, the question of how to maximize the generalization ability of such machines, together with the choice of architecture, activation functions, training set data and size, etc. makes up a huge number of possible combinations for the final NN design, whose optimal solution has not been figured yet. This paper describes a STLF system (NeuroDem) which has been used by Brazilian electric utilities for 3 years. It uses a non-parametric model based on a linear model coupled with a polynomial network, identified by pruninglgrowing mechanisms. NeuroDem has special features of data pre-processing and confidence intervals calculations, which are also described. Results of load forecasts are presented for one year with forecasting horizons from 15 min. to 168 hours ahead.Item Aplicação da transformada wavelet discreta na previsão de carga a curto prazo via redes neurais.(2004) Reis, Agnaldo José da Rocha; Silva, Alexandre Pinto Alves daThe importance of short-termload forecasting has been in-creasing lately. With deregulation and competition, energy price forecasting has become a big business. Bus-loadfore-castingis essential to feed analytical methods utilized for de- termining energy prices. The variability and non-stationarity of loads are be coming worse due to the dynamics of energy prices. Besides, the number of nodal loads to be predicted does notal low frequent interventions from load forecasting experts. More autonomous load predictors are needed in the new competitive scenario. This paper proposes novel wavelet transform-based technique for short-term load fore-casting via neural networks. Its main goal is to develop more robust load forecasters. Two whole years of load data from a North-American electric utility has been used in order to test The proposed methodology