Fluxo de potência trifásico probabilístico para redes de distribuição usando o método de estimação por pontos

In this paper the point estimation method is applied to solve the probabilistic power flow problem for unbalanced three-phase distribution systems. Through the implementation of this method the probability distribution functions of voltages (magnitude and angle) as well as the active and reactive power flows in the branches of the distribution system are determined. Two different approaches of the point estimation method are presented (2m and 2m+1 point schemes). In order to test the proposed methodology, the IEEE 34 and 123 bus test systems are used. The results obtained with both schemes are compared with the ones obtained by a Monte Carlo Simulation (MCS).

Speed estimation for induction motor using neural networks method

This work presents an alternative approach based on neural network method in order to estimate speed of induction motors, using the measurement of primary variables such as voltage and current. Induction motors are very common in many sectors of the industry and assume an important role in the national energy policy. The nowadays methodologies, which are used in diagnosis, condition monitoring and dimensioning of these motors, are based on measure of the speed variable. However, the direct measure of this variable compromises the system control and starting circuit of an electric machinery, reducing its robustness and increasing the implementation costs. Simulation results and experimental data are presented to validate the proposed approach. © 2003-2012 IEEE.

Decoupled reference generator for shunt active filters using the conservative power theory

Based on the framework of the Conservative Power Theory (CPT), this paper proposes some compensation strategies for shunt current compensators. CPT current decompositions result in several current-related terms associated with specific load characteristics, such as power consumption, energy storage, unbalances and load nonlinearities. These current components are decoupled (orthogonal) from each other and are used here to define different compensation strategies, which can be selective in minimizing particular effects of disturbing loads. Compensation strategies for single- and three-phase four-wire circuits are also considered. Simulated and experimental results are described to validate the possibilities and performance of the proposed strategies. © 2013 Brazilian Society for Automatics - SBA.

Desempeño de tanques decantadores de sólidos en un sistema de recirculación para producción de tilapia

To compare the removal efficiency of solids, turbidity and apparent color between a conventional and a column settling tanks in a recirculating aquaculture system (RAS) for tilapia farming. Materials and methods. Tilapia with a stocking density between 30 and 33 kg/m3 were cultured in a RAS consisting of a water level control box, PVC piping system, three plastic tanks for culture, conventional horizontal flow settling tank (Con.ST), column vertical flow settling tank (Col.ST), three phase fluidized bed reactor, oxygen transfer reactor, air compressor, air blower, centrifugal pump. The Con.ST operated at a volume of 1.4 m3 and hydraulic retention time (HRT) of 2.94 h; and was drained weekly for washing and sludge collection, representing a 55%discharge of system water volume. The Col.ST operated with a volume of 0.30 m3 and HRT of 0.553 h. Three daily partial draining operations were executed, representing a discharge of 50% of the system volume. Results. The mean solids removal efficiencies were: 34.01 and 44.44%for total solids; 64.45 and 71.71% for suspended solids; 21.10 and 45.65% volatile solids; 65.51% and 62.79% for turbidity; and 56.37 and 50.91% for apparent color, respectively for Con.ST and Col.ST. Conclusions. The two settling devices are useful on removal of the studied parameters and presented similar performance on turbidity and apparent color removal; however, the Col.ST was more efficient than Con.ST for solids removal, requires less space, less volume and requires less discharge water volume, displaying feasibility for its use on RAS.

Desenvolvimento e implementação de um sistema de controle de posição e velocidade de uma esteira transportadora usando inversor de frequência e microcontrolador

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Implementação de um controle digital para o compensador regenerativo de potência ativa

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Uma proposta de desenvolvimento de laboratório remoto de automação e acionamento de máquinas elétricas para uso didático, utilizando software open source

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Detecção e classificação de faltas de alta impedância em sistemas elétricos de potência usando lógica Fuzzy

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Proposta de diagnóstico para uso, instalação e descarte de transformadores de distribuição recuperados

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Um procedimento de estimação de parâmetros de linhas de transmissão baseado na teoria de decomposição modal

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Metodologia de projeto cooperativo para condicionadores de qualidade de energia

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Representação modal alternativa de linhas de transmissão trifásicas simétricas não idealmente transpostas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Aplicações da teoria da potência complexa instantânea no cálculo das grandezas de Buchholz-Goodhue

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Planejamento e projeto de circuitos secundários de distribuição de energia elétrica por meio de algoritmo busca tabu

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estimação dos parâmetros de linha de transmissão a partir de um segmento de linha discretizado

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)