A mixed-integer quadratically-constrained programming model for the distribution system expansion planning

This paper presents a mixed-integer quadratically-constrained programming (MIQCP) model to solve the distribution system expansion planning (DSEP) problem. The DSEP model considers the construction/reinforcement of substations, the construction/reconductoring of circuits, the allocation of fixed capacitors banks and the radial topology modification. As the DSEP problem is a very complex mixed-integer non-linear programming problem, it is convenient to reformulate it like a MIQCP problem; it is demonstrated that the proposed formulation represents the steady-state operation of a radial distribution system. The proposed MIQCP model is a convex formulation, which allows to find the optimal solution using optimization solvers. Test systems of 23 and 54 nodes and one real distribution system of 136 nodes were used to show the efficiency of the proposed model in comparison with other DSEP models available in the specialized literature. (C) 2014 Elsevier Ltd. All rights reserved.

Fast fault section estimation in distribution control centers using adaptive genetic algorithm

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Seleção de motobombas para o setor sucroalcooleiro

This work has the purpose to explain how the sugar and alcohol sector works, detail all the processes which uses pumps and assist in the selection and specification of pumps attached with engines, that will make part in important industry processes in the manufacture of sugar and alcohol. A bibliographic revision about the working of sugar and alcohol sector and about pumps were made to help the analysis of a case. This case had the purpose to analyze the selected pumps that were part of a initial project of an industry which aimed a future expansion. The pumps that were selected to made part of the initial project were over dimensioned and were operating out of the best performance point, making the pumps inefficient because the expansion didn't happened. The solution was to select another pump with bigger performance and less power consumption to have a decrease in the energy consumption and in the operational costs of the industry and using the extra electric energy in the industry or selling it

Geração de energia renovável em residências: aplicação de tecnologias existentes

Due to the high value of the bill that the Brazilian has been paying, one of the most expensive in the world, is becoming increasingly attractive the option for renewable energy in form of distributed micro and minigeneration. In other words, the renewable energy sources are becoming attractive not only because of environmental concerns, but also due to economic issues. This has become even more relevant and concrete after approval of rules by National Agency of Electric Energy (ANEEL) on 4/17/2012 (Normative Resolution n ° 482/2012 of 04/17/2012) aimed at reducing barriers to installation of small distributed generation, including microgeneration, with up to 100 kW of power, and minigeneration, 100 kW to 1 MW. The Normative Resolution n ° 482/2012 creates the Energy Clearing System, which allows consumers to install small generators in its consumer unit and exchange energy with the local distributor. The rule applies to generators that use renewable sources of energy (hydro, solar, biomass, wind and cogeneration qualified). In this context, this paper presents a technical and economic analysis of installing a residential microgenerating plant composed of photovoltaic cells, solar panels and small wind turbines

Analise técnico-econômica de um gaseificador Downdraft e de filtros para limpeza de gás de síntese

The biomass gasification systems have been used for a long time and prove to be a good alternative to the generation of energy problems. This type of management requires a simple installation and maintenance which gives them a high availability. In Biomass project via Call CTEnerg 33/2006-1, funded by the Ministry of Science and Technology - MCT - Brazil, the Group Energy Systems Optimization – GOSE - at FEG - UNESP built and tested two prototypes of gasifiers. These is fed with 25 kg / h of dry wood (chips), and 50 Nm3 / h of air to produce gas at a flow rate of approximately 70 Nm3 / h of wood (syngas) at a temperature approximately 600 ° C. In this work of graduation, studies were conducted on the materials used in both the gasifier as well as cleaning the filter synthesis gases. The system of gas cleaning and conditioning is vital to ensure the life of the Internal Combustion Engine. In this case the studies of different filters for small gasification systems (properties, materials used, characteristics, types, etc.) are very relevant to its use in the prototype of the college campus. Were also performed a technical and economic analysis of a cogeneration system that consists in the combination of the downdraft gasifier studied in this work, an internal combustion engine, two heat exchangers and a SRA (absorption system refrigerator). Were calculated the costs of electricity generation, hot water and cold water. Finally, we analyzed the economic feasibility of the project

Estudo comparativo do desgaste de ferramentas cerâmicas de Al2O3 em relação às de B4C + TiB2

Due to the high value of the bill that the Brazilian has been paying, one of the most expensive in the world, is becoming increasingly attractive the option for renewable energy in form of distributed micro and minigeneration. In other words, the renewable energy sources are becoming attractive not only because of environmental concerns, but also due to economic issues. This has become even more relevant and concrete after approval of rules by National Agency of Electric Energy (ANEEL) on 4/17/2012 (Normative Resolution n ° 482/2012 of 04/17/2012) aimed at reducing barriers to installation of small distributed generation, including microgeneration, with up to 100 kW of power, and minigeneration, 100 kW to 1 MW. The Normative Resolution n ° 482/2012 creates the Energy Clearing System, which allows consumers to install small generators in its consumer unit and exchange energy with the local distributor. The rule applies to generators that use renewable sources of energy (hydro, solar, biomass, wind and cogeneration qualified). In this context, this paper presents a technical and economic analysis of installing a residential microgenerating plant composed of photovoltaic cells, solar panels and small wind turbines

Sistema fotovoltaico interligado á rede eletrica no Campus da UNESP-FEG Guaratinguetá

Solar energy can be considered the largest source of energy available on earth and has attracted in recent decades, attention and interest for its rational use. The use of energy sources in a sustainable manner is essential to the survival of future generations, due to the scarcity of natural resources and their exploitation in a disorderly way. Studies related to the applications of renewable sources becomes then relevant, given its great importance as regards the conscious use of resources provided by nature, with the least possible impact on it. The present study presents an evaluation of generation potential and feasibility of implementing a solar photovoltaic connected to the grid and connected to the roofs of some buildings of the Faculty of Engineering of Guaratinguetá - FEG, to supply the demand of electric energy consumption on campus and attempting to inject a possible surplus power generation in local power grid, increasing network capacity and reducing peak loads

Técnicas de energia elétrica sustentável aplicadas em edificações

One of the majors concerns in society today is to decrease the environmental impact caused by human activities and natural resource exploration. From this need to be more careful with the environment arose, in the field of civil construction, the term sustainable building. Projects that use natural resources rationally, without ceasing to bring comfort and functionality for customers, are becoming more a reality. This paper presents the share of electric energy in a sustainable building, with the analysis of the available renewable energies used in a project, presentation of new constructive techniques and technologies that are constantly emerging to achieve greater energy efficiency, with an appropriate use of energy received, also a decrease of the energy consumed by some devices present in a residence or business

Comercialização de energia elétrica no Brasil

How companies can sell their surplus production capacity of electric power in Brazil? This work was developed from the question presented and focusing on clarification of procedures to enter the Brazilian electricity market by providing basic guidelines based on resolutions by National Agency of Electric Energy, National System Operator procedures and rules of the Assembly of Electric Energy Commercialization. It features subsidy to companies that fit this profile to evaluate the possibility to sell their surplus electricity. The general aim was to analyze the procedures and the necessary steps to make this sale happen. Was developed through a literature review where an overview of the Brazilian electric sector and a case study of a company that has excess capacity of electricity, but doesn’t make its marketing. Resulted in the expected clarification as well as the incentive for companies through the information presented, the entry in this trade since power is still crucial to the country's economic growth and ensure its availability in quantity demanded is a challenge of the utmost importance for satisfactory results are achieved economic development contributing to the progress of our society

Projeto e implantação de pequena central de geração hidrelétrica: análise de caso

The objective of this work is to study the implantation feasibility of a small hydropower system in a rural area in Guaratinguetá. Due to its location and accessibility, and the costs involved in extending the public distribution line to the property it could turn become viable the construction of an individual electric generation system. As alternatives, a solar photovoltaic system and combustion engine-electric generator systems were considered. However, the existence of a small river inside the property, the construction of a micro hydropower plant was taken into account. The choice of the micro power hydropower plant was determined by the owner and was based on the costs. The topographic and hydrological profiles as well as the geometrical characteristics of the system, including the civil infrastructure needed and the more adequate turbine, were determined. Finally, the cost spreadsheet was set and the results were compared with those calculated for the extension of the available public distribution system

Estudo de impacto de ações de eficiência energética em instalações elétricas residenciais

This paper addresses methods of reducing the electric energy consumption on residences by the means of constructive measures and replacement of electric devices. Analyzing their impacts on residential and national level based on data issued by IBGE (Brazilian Institute of Geography and Statistics) and PROCEL (National Program for Electricity Conservation).

Análise de conversor multipulso utilizando transformador com culatra intermediária

Pós-graduação em Engenharia Elétrica - FEIS

Alocação de modem PLC utilizando SNR em uma rede elétrica de baixa tensão

Pós-graduação em Engenharia Elétrica - FEIS

Planejamento de reativos em sistemas elétricos de potência multi-área através de modelos estocásticos

Pós-graduação em Engenharia Elétrica - FEIS

Caracterização da cinza de bagaço de cana-de-açúcar e aplicação no solo

Pós-graduação em Agronomia (Ciência do Solo) - FCAV