Comparative analysis for reactive energy measurement methodologies, under non-sinusoidal conditions in three-phase four-wire circuits

This paper presents some methodologies for reactive energy measurement, considering three modern power theories that are suitable for three-phase four-wire non-sinusoidal and unbalanced circuits. The theories were applied in some profiles collected in electrical distribution systems which have real characteristics for voltages and currents measured by commercial reactive energy meters. The experimental results are presented in order to analyze the accuracy of the methodologies, considering the standard IEEE 1459-2010 as a reference. Finally, for additional comparisons, the theories will be confronted with the modern Yokogawa WT3000 energy meter and three samples of a commercial energy meter through an experimental setup. © 2011 IEEE.

An analysis of Generalized Symmetrical Components in non sinusoidal three phase systems

This paper presents the study of the so called Generalized Symmetrical Components, proposed by Tenti et. al. to the analysis of unbalanced periodic non sinusoidal three phase systems. As a result, it was possible to establish a proper relationship between such of generalized symmetrical components and Fortescue symmetrical components to the harmonic frequencies that compose a generic periodic non sinusoidal three phase system. © 2011 IEEE.

A comparative study of MPPT strategies and a novel singlephase integrated buck-boost inverter for small wind energy conversion systems

This paper presents the analysis of some usual MPPT (Maximum Power Point Tracking) strategies intended for small wind energy conversion (up to 1kW) based on permanent magnet synchronous generators (PMSG), considering the stand-alone application for a novel buck-boost integrated inverter. Each MPPT method is analytically introduced and then it is simulated using MatLab/Simulink considering standard conditions of wind and also commercially available turbines and generators. The extracted power in each case is compared with the maximum available power, so the tracking factor is calculated for each method. Thus, the focus is on the application to improve the efficiency of stand-alone wind energy conversion systems (WECS) with battery chargers and AC load supplied by inverter. Therefore, for this purpose a novel single phase buck-boost integrated inverter is introduced. Finally, the main experimental results for the introduced inverter are presented. © 2011 IEEE.

Tri-state Space Vector Modulation for Three-phase integrated inverters

The aim of this work is to present a modified Space Vector Modulation (SVM) suitable for Tri-state Three-phase inverters. A standard SVM algorithm and the Tri-state PWM (Pulse Width Modulation) are presented and their concept are mixed into the novel SVM. The proposed SVM is applied to a three-phase tri-state integrated Boost inverter, intended to Photovoltaic Energy Applications. The main features for this novel SVM are validated through simulations and also by experimental tests. The obtained results prove the feasibility of the proposal. © 2011 IEEE.

Three-phase tri-state integrated boost inverter with special space vector and dq0 control

This paper presents a three-phase integrated inverter suitable for stand-alone and grid-connected applications. Furthermore, the utilization of the special features of the tri-state coupled with the new space vector modulation allows the converter to present an attractive degree of freedom for the designing of the controllers. Additionally, the control is derived through dq0 transformation, all the system is described and interesting simulation results are available to confirm the proposal. © 2012 IEEE.

Utilização de redes neurais recorrentes na caracterização de cargas não lineares em sistemas elétricos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos das distorções harmônicas (tensões e correntes) e desequilíbrios (tensões) em medidores eletrônicos trifásicos de energia elétrica ativa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Supressor eletromagnético de componentes harmônicas de sequência zero

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise e aplicação de compensação reativa em redes secundária de distribuição com cargas não lineares

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Um sistema eletrônico de 2kW para emulação/simulação experimental da característica estática de saída, tensão (versus) corrente, de sistemas de geração com células combustível tipo PEM

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise experimental de erros de medição de energia elétrica ativa em medidores eletromagnéticos tipo indução, sujeitos a distorções harmônicas de correntes e tensões, em sistemas equilibrados e desequilibrados

Pós-graduação em Engenharia Elétrica - FEIS

Inversores integrados monofásicos aplicados em sistemas fotovoltaicos com conexão à rede de distribuição de energia elétrica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Controle flexível para conversores monofásicos conectados a sistemas elétricos distorcidos de baixa tensão

This paper presents a technique to add flexibility in the control of power electronic converters. The power converter can function as an active power filter, as a local power source interface or perform both functions i. e. mitigate current disturbances and inject power into the grid simultaneously, configuring it as a multifunctional device. The main goal is to extract the full capability of the grid connected power electronic converter to achieve maximum benefits. To achieve this goal, the orthogonal current decomposition of the Conservative Power Theory is used. Each orthogonal current component is weighted by means of different compensation factors (k_i), which are set instantaneously and independently, in any percentage by means of the load performance factors (λ_i), providing an online flexibility in relation to compensation objectives. Finally, to validate the effectiveness and performance the proposed approach, simulations and experimental results are presented.

Transformer Operation at Deep Saturation: Model and Parameter Determination

This paper proposes a model that adequately describes the operation of the transformer at deep saturation, suitable for power-electronics applications, and a method for determining its parameters. Simulation and experimental results are presented to confirm the validity of the model and the method.

Internal Model Principle: extension to the switching case and applications

This thesis deals with a novel control approach based on the extension of the well-known Internal Model Principle to the case of periodic switched linear exosystems. This extension, inspired by power electronics applications, aims to provide an effective design method to robustly achieve the asymptotic tracking of periodic references with an infinite number of harmonics. In the first part of the thesis the basic components of the novel control scheme are described and preliminary results on stabilization are provided. In the second part, advanced control methods for two applications coming from the world high energy physics are presented.