Bruno Wanderley França - Academia.edu (original) (raw)

Papers by Bruno Wanderley França

Research paper thumbnail of Fuzzy Adaptive P&O Control for MPPT of a Photovoltaic Module

Journal of Power and Energy Engineering, 2014

In this work a Maximum Power Point Tracker (MPPT) for photovoltaic modules is developed using fuz... more In this work a Maximum Power Point Tracker (MPPT) for photovoltaic modules is developed using fuzzy logic. As it is well known, the output of the photovoltaic module is a non-linear curve which has a unique point of maximum power (MPP) for a given condition of radiation and temperature. When a load is connected to the module, only in very specifics cases, the operation point will coincide with the MPP, for any other conditions the system will not operate with maximum power. Thus MPPT circuits must guarantee that photovoltaic modules operate with its maximum power at most of the time, independently to the radiation and temperature conditions. In order to achieve this objective, in this paper the input variables of the controller are transformed into linguistic variables, which associate with a set of rules results the displacement of the operation point so as to transfer the maximum power from the photovoltaic module to the load.

Research paper thumbnail of An Improved iUPQC Controller to Provide Additional Grid-Voltage Regulation as a STATCOM

IEEE Transactions on Industrial Electronics, 2015

This paper presents an improved controller for the dual topology of the unified power quality con... more This paper presents an improved controller for the dual topology of the unified power quality conditioner (iUPQC) extending its applicability in power-quality compensation, as well as in microgrid applications. By using this controller, beyond the conventional UPQC power quality features, including voltage sag/swell compensation, the iUPQC will also provide reactive power support to regulate not only the load-bus voltage but also the voltage at the grid-side bus. In other words, the iUPQC will work as a static synchronous compensator (STATCOM) at the grid side, while providing also the conventional UPQC compensations at the load or microgrid side. Experimental results are provided to verify the new functionality of the equipment.

Research paper thumbnail of Compensação série como alternativa para o plano de expansão da distribuição

Revista de Tecnologia Aplicada

RESUMO ESTRUTURADO Diante da necessidade de soluções de planejamento do setor elétrico cada vez m... more RESUMO ESTRUTURADO Diante da necessidade de soluções de planejamento do setor elétrico cada vez mais direcionadas ao aproveitamento racional de recursos, alinhado ainda ao crescimento por demanda de energia elétrica que se evidencia nos sistemas de distribuição, este artigo propõe a aplicação de compensação série em um sistema distribuição de energia elétrica de uma concessionária do sudeste brasileiro como alternativa às técnicas convencionais, visando a resolução de criticidades de tensão e otimização de investimentos no circuito. Nesse sentido, o trabalho objetiva fornecer embasamento teórico, apresentar os conceitos relativos ao dimensionamento, além dos requisitos necessários para viabilizar a instalação de capacitores série no setor de distribuição. Por fim, serão demonstrados os resultados obtidos no estudo realizado para um sistema real considerando a inserção de compensação série ao longo de um alimentador de característica rural, através da utilização dos softwares CYMDIST...

Research paper thumbnail of An Enhanced Shunt Active Filter Based on Synchronverter Concept

IEEE Journal of Emerging and Selected Topics in Power Electronics, 2021

This article proposes a shunt active filter (SAF) operating as a Synchronverter to enhance its pe... more This article proposes a shunt active filter (SAF) operating as a Synchronverter to enhance its performance, including the virtual inertia functionality. The SAF behaves as a voltage source with a low-impedance path for harmonic contents. Synchronverter behavior is used together with selective filtering through proportional-resonant controllers to provide selective harmonic filtering of the load current, selective harmonic blocking of the source current, and low-impedance path for nonselected harmonic contents from the load and the source currents. The virtual inertia functionality aims to contribute to frequency stability during power system transients. Besides filtering unbalanced and harmonic contents and compensating for reactive power, the SAF contributes to inertia response during frequency transients. A tuning design method is proposed to ensure stability and proper conditioning of the power-quality issues. The reduced quantity of parameters to be tuned is another advantage of the proposed controller. Simulation and experimental results validate the compensation performance of the SAF.

Research paper thumbnail of A review of superconducting fault current limiters compared with other proven technologies

Research paper thumbnail of Novel Design of a Hybrid Superconducting Fault Current Limiter with Controlled Solid-State Device

Journal of Microwaves, Optoelectronics and Electromagnetic Applications, 2021

Fault current limiters are essential devices used to protect the power system and its equipment a... more Fault current limiters are essential devices used to protect the power system and its equipment against high levels of fault current, which are growing up due to the increase of new power sources. This paper proposes a novel design of a Hybrid Superconducting Fault Current Limiter (Hybrid SFCL), which is composed basically by thyristors in series with a superconducting element. This branch is connected in parallel to an air-core reactor, which improves limitation and ensures the safe operation of the superconductor element. Another advantage of this topology is the use of the voltage drop in the superconductor as an input parameter to the controller. This voltage is used to detect the fault, which avoids the need for a current sensor and, consequently, reduces the manufacturing costs. In this work, the PSCAD/EMTDC software was employed to modeling the Hybrid SFCL and the 2G superconducting tape, which was modeled considering the thermal-electrical analysis. The results show that the fault current is efficiently limited, and the developed controller strategy has shown a relatively good performance. Furthermore, the proposed system guarantees a fast recovery time, in the order of 500 ms, which is a good advantage when compared to the conventional resistive SFCL.

Research paper thumbnail of Energy Efficiency Study for the Distribution System Using Low Voltage Transformer Under Harmonic Conditions

Anais do Simpósio Brasileiro de Sistemas Elétricos 2020, 2020

In Brazil, technical energy losses in power distribution systems are determined by power flow stu... more In Brazil, technical energy losses in power distribution systems are determined by power flow studies considering medium and low voltage systems, according to ANEEL recommendations, presented in PRODIST Module 7. These technical losses occur due to physical phenomena and are intrinsically associated with the energy distribution process. However, standards currently do not consider energy losses from harmonic components generated by nonlinear loads, which represent almost all the loads present in electrical systems worldwide. Thus, this paper aims to analyze the operation of a low voltage transformer under harmonic current conditions and to evaluate not only the operation temperature of the equipment, but also to verify the energy losses in it. This test is performed on a laboratory platform and the results are experimental using an adjustable three-phase source and a 3kVA three-phase transformer.

Research paper thumbnail of A New Immersion and Invariance Control and Stable Deep Learning Fuzzy Approach for Power/Voltage Control Problem

IEEE Access, 2021

Background: The use of renewable energies is extended due to their valuable features such as abun... more Background: The use of renewable energies is extended due to their valuable features such as abundant and clarity. The microgrids that include the renewable energies are widely used in various applications such as power supplying of remote areas, increasing the network reliability, reducing the greenhouse gas emission, reducing the consumption demand, eliminating the consumption peaks, and so on. But, energy management in the these systems in an challenging problem. Because, there are some natural perturbations such as variation output load, grid-side faults and changes of irradiation and temperature. Aim and Objective: The problem is to design a controller to regulate the output voltage/energy under aforementioned disturbances. Methods: The paper presents a new approach for energy management in Photovoltaic (PV)/Battery/Fuel Cells (FC) systems. The uncertainties are compensated by the new optimization rules based on Immersion and Invariance (I&I) theorem and proposed deep learning type-2 fuzzy logic compensator (T2FLC). The objective function of T2FLC is to minimize the tracking error in presence of perturbations. The adaptation rules are derived such that the I&I stabilization criterions are satisfied. Both rules and fuzzy sets (FSs) of T2FLCs are optimized by guaranteed stability rules to tackle the effect of perturbations and estimation errors. Results and Discussion: It is shown that a well voltage/energy regulation performance is achieved under variation of temperature, suddenly changes of load and variation of irradiation. A comparison with similar controllers demonstrates the superiority of the suggested approach. Conclusion: The suggested regulator do not depend on the mathematical models, and results in good accuracy under difficult conditions, then it can be used in various applications.

Research paper thumbnail of Impacto de Harmônicos e Filtros Passivos em Simulações de Desempenho Dinâmico de Conversores com Capacitores de Comutação

Anais da XIV Conferência Brasileira sobre Qualidade da Energia Elétrica, 2021

Research paper thumbnail of Ferramenta de desenvolvimento para estudos em redes de distribuição ativas

Diferencas entre o codigo computacional utilizado para o controle de equipamentos eletronicos de ... more Diferencas entre o codigo computacional utilizado para o controle de equipamentos eletronicos de Redes de Distribuicao Ativas (RDA) simulados e o codigo embarcado para o controle dos equipamentos reais podem criar discrepâncias entre os resultados obtidos nas duas etapas. Foi desenvolvido um conjunto de bibliotecas na linguagem C de programacao para o controle de inversores trifasicos com portabilidade entre diferentes plataformas de processamento que evita a refatoracao de codigo, reduzindo o tempo de desenvolvimento de software e as diferencas entre codigo de simulacao e codigo embarcado. As bibliotecas foram empregadas em um microcontrolador da Texas TMS320F28379D e no software de simulacao PSIM para demonstrar a eficacia da ferramenta e comparar de resultados.

Research paper thumbnail of Hardware-in-the-Loop para desenvolvimento de Software embarcado em DSPs utilizando ambiente PSCAD/EMTDC

O numero de equipamentos controlados por microcontroladores cresce a medida que aumenta a disponi... more O numero de equipamentos controlados por microcontroladores cresce a medida que aumenta a disponibilidade do uso desses...

Research paper thumbnail of Ferroresonance evaluation on capacitor voltage transformers

Electrical Engineering, 2020

Ferroresonance has been a widely studied area in the last few decades due to the nonlinear behavi... more Ferroresonance has been a widely studied area in the last few decades due to the nonlinear behavior and power quality problems it presents. Some power quality problems related to the ferroresonance phenomenon are sustained overvoltage and overcurrent and maintained levels of waveform distortions. The phenomenon can lead to the dielectric breakdown of electrical equipment, thermal problems, and misoperation of protective relays. It can present itself in a circuit that involves a nonlinear inductance associated with capacitance and low losses. This paper analyzes the ferroresonance test in a capacitor voltage transformer through Simulink ® simulation. It divided a cycle of a sine wave into 72 different points to apply controlled short-circuits in the secondary terminal of the transformer. The aim is to study the relationship between the time when a short-circuit is applied, and the peak voltage of the first positive half-cycle after the short-circuit is removed. Therefore, the worst-case scenario of the short-circuit application was verified. Results demonstrate that there is a most critical situation during short-circuits at the CVT's secondary terminals.

Research paper thumbnail of Sliding Droop Control For Distributed Generation In Microgrids

Eletrônica de Potência, 2017

Research paper thumbnail of Sliding Droop Control For Distributed Generation In Microgrids

Eletrônica de Potência, 2017

This paper proposes a fully autonomous controller that slides the droop curves of a Static Synchr... more This paper proposes a fully autonomous controller that slides the droop curves of a Static Synchronous Generator, avoiding the need of hierarchical controllers to perform power sharing and frequency and voltage regulation. The aim of this controller is to enhance the primary controller in order to perform additional functionalities in a similar way as those performed in a secondary control level hierarchy, avoiding the need of a communication-system and without mischaracterizing the primary behavior as a virtual synchronous machine. The proposed seamless controller is still compatible with conventional communication-systems, and can receive inputs from hierarchical controllers. In grid-connected microgrids, distributed generation (DG) units perform active-power supply and adequate voltage regulation, whereas the system frequency is imposed by the grid. Contrarily, in islanded microgrids, DG units have to perform activepower sharing between all units, reactive-power sharing, as well as to ensure adequate frequency control and voltage regulation. When static droop curves are employed, power dispatch planning along with coordinated set of DG units is required to achieve accurate active-power sharing. This drawback is mitigated with the proposed fully autonomous controller. Simulation results were obtained in a microgrid scenario to demonstrate the effective approach for power sharing. Experimental results are also presented.

Research paper thumbnail of Technical and Operational Analysis of Fault Current Limiters

Eletrônica de Potência, 2020

Resumo-O aumento da demanda de energia elétrica e o crescimento da geração distribuída levam ao a... more Resumo-O aumento da demanda de energia elétrica e o crescimento da geração distribuída levam ao aumento da corrente de curto-circuito nas subestações. A maioria das subestações brasileiras, por exemplo, foram projetada décadas atrás, portanto seus equipamentos podem não suportar os novos níveis de corrente de curtocircuito. Para proteger os equipamentos instalados ou evitar altos custos de investimento na sua substituição destes, é possível instalar limitadores de corrente de curto-circuito. Este trabalho apresenta uma avaliação de duas topologias de limitadores através de análises dos aspectos técnicos e operacionais. Protótipos de pequena escala são empregados para entender melhor essas análises. As topologias estudadas são denominadas indutor série chaveado e circuito ressonante. A corrente de curto-circuito teve uma redução para a topologia indutor série chaveado de 69,7% e 72,6% para a topologia ressonante.

Research paper thumbnail of Robust Model Predictive Rotor Current Control of a DFIG Connected to a Distorted and Unbalanced Grid Driven by a Direct Matrix Converter

IEEE Transactions on Sustainable Energy, 2018

The DFIG has been widely used in the wind power industry due to its technical advantages. However... more The DFIG has been widely used in the wind power industry due to its technical advantages. However, current researches are being developed aiming at overcoming some of its drawbacks concerning reliability, efficiency and power quality. Since the wind farms are usually located at remote places, connected to weak grids, high reliability is required and some power quality issues deserve attention. This paper proposes a lowcomplexity, robust control of a DFIG driven by a direct matrix converter based on a model predictive rotor current control. The matrix converter is interesting due to the absence of the bulky and sensitive dc-link capacitors, leading to higher reliability. The predictive control is used to perform speed regulation. Moreover, this combination of converter and straightforward control is proven to be a robust technique that naturally compensates for stator current issues, which arises due to a low-power-quality grid voltage. Besides, a linear model of the proposed system is presented in order to be possible to use the linear-control-theory tools to execute the system control design. A processor-in-the-loop simulation is employed to validate the proposed control.

Research paper thumbnail of Projeto e Aplica��o de Filtros LCL+RC em Inversores Conectados � Rede

Proceedings XXII Congresso Brasileiro de Autom�tica, 2018

Research paper thumbnail of Opendss Modeling for Steady-State Analysis of Distributed Generation Control Techniques

Proceedings XXII Congresso Brasileiro de Autom�tica, 2018

O objetivo principal deste artigo e modelar na analise estatica os controladores de geracao em mi... more O objetivo principal deste artigo e modelar na analise estatica os controladores de geracao em microrredes atraves da simulacao no OPENDSS. Esses controladores foram projetados anteriormente em simuladores de transitorios de sistema de energia, como PSCAD / EMTDC, que permitem a analise de regime dinâmico com um certo nivel de custo computacional. Desta forma, a modelagem no OPENDSS deve reproduzir fielmente o desempenho estavel desses controladores para que o simulador possa ser usado para investigar altas penetracoes da geracao distribuida com custos computacionais relativamente reduzidos. Para este fim, inicialmente os esforcos se concentraram em determinar uma microrede a ser implementada; para em seguida, poder, atraves da analise estatica no OpenDSS, comparar os resultados, os quais confirmarao aqueles obtidos na analise dinâmica do controlador Sliding Droop, que permitira obter conclusoes do estado da rede em regime permanente antes de executar as simulacoes dinâmicas. Os resultados em regime permanente obtidos pela abordagem proposta foram validados pela simulacao dinâmica. Portanto a metodologia proposta neste artigo e promissora para analises de microrredes isoladas o controle Sliding Droop.

Research paper thumbnail of Design and computational modeling of fault current limiter topologies

The increase in demand for electric power and the insertion of a distributed generation led to th... more The increase in demand for electric power and the insertion of a distributed generation led to the rise of the short-circuit current in substations. Most of these Brazilian substations were designed decades ago, because of that their equipment may not support the new short-circuit current levels. To protect the installed equipment and avoid excessive costs replacing old devices, it is possible to install Fault Current Limiters (FCLs). This document is a report from an R&D project that evaluated FCL topologies considering real parameters in simulation from used equipment, concluding that the selected FCL topologies accomplished their technical objective. However, before implementing these topologies in the distribution system, one should consider the technical and economic feasibility of using semiconductor switching devices.

Research paper thumbnail of Detailed modelling and analysis of digital mho distance relay with single-pole operation

Acta Polytechnica, 2021

This paper introduces a methodology for modelling a digital admittance-type distance relay using ... more This paper introduces a methodology for modelling a digital admittance-type distance relay using PSCAD/EMTDC. The proposed distance relay was tested in a simulation of the Brazilian power grid with predetermined fault scenarios. The goal of this paper is to make a detailed evaluation of the mho distance relay. The main aspects include the correct operation of the distance relay, fault resistance effects on the mho characteristics, and the fault detection time of this relay. A new approach to analyse the fault detection time is presented, considering several simulated fault scenarios. The results demonstrate that the fault resistance influences the fault detection time and severely affects the distance relay’s general performance. The fault detection time is not constant. It varies within a time interval, considering different fault types, fault locations, and fault resistances. The confidence interval calculation provides a detailed range of the fault detection time, considering its...

Research paper thumbnail of Fuzzy Adaptive P&O Control for MPPT of a Photovoltaic Module

Journal of Power and Energy Engineering, 2014

In this work a Maximum Power Point Tracker (MPPT) for photovoltaic modules is developed using fuz... more In this work a Maximum Power Point Tracker (MPPT) for photovoltaic modules is developed using fuzzy logic. As it is well known, the output of the photovoltaic module is a non-linear curve which has a unique point of maximum power (MPP) for a given condition of radiation and temperature. When a load is connected to the module, only in very specifics cases, the operation point will coincide with the MPP, for any other conditions the system will not operate with maximum power. Thus MPPT circuits must guarantee that photovoltaic modules operate with its maximum power at most of the time, independently to the radiation and temperature conditions. In order to achieve this objective, in this paper the input variables of the controller are transformed into linguistic variables, which associate with a set of rules results the displacement of the operation point so as to transfer the maximum power from the photovoltaic module to the load.

Research paper thumbnail of An Improved iUPQC Controller to Provide Additional Grid-Voltage Regulation as a STATCOM

IEEE Transactions on Industrial Electronics, 2015

This paper presents an improved controller for the dual topology of the unified power quality con... more This paper presents an improved controller for the dual topology of the unified power quality conditioner (iUPQC) extending its applicability in power-quality compensation, as well as in microgrid applications. By using this controller, beyond the conventional UPQC power quality features, including voltage sag/swell compensation, the iUPQC will also provide reactive power support to regulate not only the load-bus voltage but also the voltage at the grid-side bus. In other words, the iUPQC will work as a static synchronous compensator (STATCOM) at the grid side, while providing also the conventional UPQC compensations at the load or microgrid side. Experimental results are provided to verify the new functionality of the equipment.

Research paper thumbnail of Compensação série como alternativa para o plano de expansão da distribuição

Revista de Tecnologia Aplicada

RESUMO ESTRUTURADO Diante da necessidade de soluções de planejamento do setor elétrico cada vez m... more RESUMO ESTRUTURADO Diante da necessidade de soluções de planejamento do setor elétrico cada vez mais direcionadas ao aproveitamento racional de recursos, alinhado ainda ao crescimento por demanda de energia elétrica que se evidencia nos sistemas de distribuição, este artigo propõe a aplicação de compensação série em um sistema distribuição de energia elétrica de uma concessionária do sudeste brasileiro como alternativa às técnicas convencionais, visando a resolução de criticidades de tensão e otimização de investimentos no circuito. Nesse sentido, o trabalho objetiva fornecer embasamento teórico, apresentar os conceitos relativos ao dimensionamento, além dos requisitos necessários para viabilizar a instalação de capacitores série no setor de distribuição. Por fim, serão demonstrados os resultados obtidos no estudo realizado para um sistema real considerando a inserção de compensação série ao longo de um alimentador de característica rural, através da utilização dos softwares CYMDIST...

Research paper thumbnail of An Enhanced Shunt Active Filter Based on Synchronverter Concept

IEEE Journal of Emerging and Selected Topics in Power Electronics, 2021

This article proposes a shunt active filter (SAF) operating as a Synchronverter to enhance its pe... more This article proposes a shunt active filter (SAF) operating as a Synchronverter to enhance its performance, including the virtual inertia functionality. The SAF behaves as a voltage source with a low-impedance path for harmonic contents. Synchronverter behavior is used together with selective filtering through proportional-resonant controllers to provide selective harmonic filtering of the load current, selective harmonic blocking of the source current, and low-impedance path for nonselected harmonic contents from the load and the source currents. The virtual inertia functionality aims to contribute to frequency stability during power system transients. Besides filtering unbalanced and harmonic contents and compensating for reactive power, the SAF contributes to inertia response during frequency transients. A tuning design method is proposed to ensure stability and proper conditioning of the power-quality issues. The reduced quantity of parameters to be tuned is another advantage of the proposed controller. Simulation and experimental results validate the compensation performance of the SAF.

Research paper thumbnail of A review of superconducting fault current limiters compared with other proven technologies

Research paper thumbnail of Novel Design of a Hybrid Superconducting Fault Current Limiter with Controlled Solid-State Device

Journal of Microwaves, Optoelectronics and Electromagnetic Applications, 2021

Fault current limiters are essential devices used to protect the power system and its equipment a... more Fault current limiters are essential devices used to protect the power system and its equipment against high levels of fault current, which are growing up due to the increase of new power sources. This paper proposes a novel design of a Hybrid Superconducting Fault Current Limiter (Hybrid SFCL), which is composed basically by thyristors in series with a superconducting element. This branch is connected in parallel to an air-core reactor, which improves limitation and ensures the safe operation of the superconductor element. Another advantage of this topology is the use of the voltage drop in the superconductor as an input parameter to the controller. This voltage is used to detect the fault, which avoids the need for a current sensor and, consequently, reduces the manufacturing costs. In this work, the PSCAD/EMTDC software was employed to modeling the Hybrid SFCL and the 2G superconducting tape, which was modeled considering the thermal-electrical analysis. The results show that the fault current is efficiently limited, and the developed controller strategy has shown a relatively good performance. Furthermore, the proposed system guarantees a fast recovery time, in the order of 500 ms, which is a good advantage when compared to the conventional resistive SFCL.

Research paper thumbnail of Energy Efficiency Study for the Distribution System Using Low Voltage Transformer Under Harmonic Conditions

Anais do Simpósio Brasileiro de Sistemas Elétricos 2020, 2020

In Brazil, technical energy losses in power distribution systems are determined by power flow stu... more In Brazil, technical energy losses in power distribution systems are determined by power flow studies considering medium and low voltage systems, according to ANEEL recommendations, presented in PRODIST Module 7. These technical losses occur due to physical phenomena and are intrinsically associated with the energy distribution process. However, standards currently do not consider energy losses from harmonic components generated by nonlinear loads, which represent almost all the loads present in electrical systems worldwide. Thus, this paper aims to analyze the operation of a low voltage transformer under harmonic current conditions and to evaluate not only the operation temperature of the equipment, but also to verify the energy losses in it. This test is performed on a laboratory platform and the results are experimental using an adjustable three-phase source and a 3kVA three-phase transformer.

Research paper thumbnail of A New Immersion and Invariance Control and Stable Deep Learning Fuzzy Approach for Power/Voltage Control Problem

IEEE Access, 2021

Background: The use of renewable energies is extended due to their valuable features such as abun... more Background: The use of renewable energies is extended due to their valuable features such as abundant and clarity. The microgrids that include the renewable energies are widely used in various applications such as power supplying of remote areas, increasing the network reliability, reducing the greenhouse gas emission, reducing the consumption demand, eliminating the consumption peaks, and so on. But, energy management in the these systems in an challenging problem. Because, there are some natural perturbations such as variation output load, grid-side faults and changes of irradiation and temperature. Aim and Objective: The problem is to design a controller to regulate the output voltage/energy under aforementioned disturbances. Methods: The paper presents a new approach for energy management in Photovoltaic (PV)/Battery/Fuel Cells (FC) systems. The uncertainties are compensated by the new optimization rules based on Immersion and Invariance (I&I) theorem and proposed deep learning type-2 fuzzy logic compensator (T2FLC). The objective function of T2FLC is to minimize the tracking error in presence of perturbations. The adaptation rules are derived such that the I&I stabilization criterions are satisfied. Both rules and fuzzy sets (FSs) of T2FLCs are optimized by guaranteed stability rules to tackle the effect of perturbations and estimation errors. Results and Discussion: It is shown that a well voltage/energy regulation performance is achieved under variation of temperature, suddenly changes of load and variation of irradiation. A comparison with similar controllers demonstrates the superiority of the suggested approach. Conclusion: The suggested regulator do not depend on the mathematical models, and results in good accuracy under difficult conditions, then it can be used in various applications.

Research paper thumbnail of Impacto de Harmônicos e Filtros Passivos em Simulações de Desempenho Dinâmico de Conversores com Capacitores de Comutação

Anais da XIV Conferência Brasileira sobre Qualidade da Energia Elétrica, 2021

Research paper thumbnail of Ferramenta de desenvolvimento para estudos em redes de distribuição ativas

Diferencas entre o codigo computacional utilizado para o controle de equipamentos eletronicos de ... more Diferencas entre o codigo computacional utilizado para o controle de equipamentos eletronicos de Redes de Distribuicao Ativas (RDA) simulados e o codigo embarcado para o controle dos equipamentos reais podem criar discrepâncias entre os resultados obtidos nas duas etapas. Foi desenvolvido um conjunto de bibliotecas na linguagem C de programacao para o controle de inversores trifasicos com portabilidade entre diferentes plataformas de processamento que evita a refatoracao de codigo, reduzindo o tempo de desenvolvimento de software e as diferencas entre codigo de simulacao e codigo embarcado. As bibliotecas foram empregadas em um microcontrolador da Texas TMS320F28379D e no software de simulacao PSIM para demonstrar a eficacia da ferramenta e comparar de resultados.

Research paper thumbnail of Hardware-in-the-Loop para desenvolvimento de Software embarcado em DSPs utilizando ambiente PSCAD/EMTDC

O numero de equipamentos controlados por microcontroladores cresce a medida que aumenta a disponi... more O numero de equipamentos controlados por microcontroladores cresce a medida que aumenta a disponibilidade do uso desses...

Research paper thumbnail of Ferroresonance evaluation on capacitor voltage transformers

Electrical Engineering, 2020

Ferroresonance has been a widely studied area in the last few decades due to the nonlinear behavi... more Ferroresonance has been a widely studied area in the last few decades due to the nonlinear behavior and power quality problems it presents. Some power quality problems related to the ferroresonance phenomenon are sustained overvoltage and overcurrent and maintained levels of waveform distortions. The phenomenon can lead to the dielectric breakdown of electrical equipment, thermal problems, and misoperation of protective relays. It can present itself in a circuit that involves a nonlinear inductance associated with capacitance and low losses. This paper analyzes the ferroresonance test in a capacitor voltage transformer through Simulink ® simulation. It divided a cycle of a sine wave into 72 different points to apply controlled short-circuits in the secondary terminal of the transformer. The aim is to study the relationship between the time when a short-circuit is applied, and the peak voltage of the first positive half-cycle after the short-circuit is removed. Therefore, the worst-case scenario of the short-circuit application was verified. Results demonstrate that there is a most critical situation during short-circuits at the CVT's secondary terminals.

Research paper thumbnail of Sliding Droop Control For Distributed Generation In Microgrids

Eletrônica de Potência, 2017

Research paper thumbnail of Sliding Droop Control For Distributed Generation In Microgrids

Eletrônica de Potência, 2017

This paper proposes a fully autonomous controller that slides the droop curves of a Static Synchr... more This paper proposes a fully autonomous controller that slides the droop curves of a Static Synchronous Generator, avoiding the need of hierarchical controllers to perform power sharing and frequency and voltage regulation. The aim of this controller is to enhance the primary controller in order to perform additional functionalities in a similar way as those performed in a secondary control level hierarchy, avoiding the need of a communication-system and without mischaracterizing the primary behavior as a virtual synchronous machine. The proposed seamless controller is still compatible with conventional communication-systems, and can receive inputs from hierarchical controllers. In grid-connected microgrids, distributed generation (DG) units perform active-power supply and adequate voltage regulation, whereas the system frequency is imposed by the grid. Contrarily, in islanded microgrids, DG units have to perform activepower sharing between all units, reactive-power sharing, as well as to ensure adequate frequency control and voltage regulation. When static droop curves are employed, power dispatch planning along with coordinated set of DG units is required to achieve accurate active-power sharing. This drawback is mitigated with the proposed fully autonomous controller. Simulation results were obtained in a microgrid scenario to demonstrate the effective approach for power sharing. Experimental results are also presented.

Research paper thumbnail of Technical and Operational Analysis of Fault Current Limiters

Eletrônica de Potência, 2020

Resumo-O aumento da demanda de energia elétrica e o crescimento da geração distribuída levam ao a... more Resumo-O aumento da demanda de energia elétrica e o crescimento da geração distribuída levam ao aumento da corrente de curto-circuito nas subestações. A maioria das subestações brasileiras, por exemplo, foram projetada décadas atrás, portanto seus equipamentos podem não suportar os novos níveis de corrente de curtocircuito. Para proteger os equipamentos instalados ou evitar altos custos de investimento na sua substituição destes, é possível instalar limitadores de corrente de curto-circuito. Este trabalho apresenta uma avaliação de duas topologias de limitadores através de análises dos aspectos técnicos e operacionais. Protótipos de pequena escala são empregados para entender melhor essas análises. As topologias estudadas são denominadas indutor série chaveado e circuito ressonante. A corrente de curto-circuito teve uma redução para a topologia indutor série chaveado de 69,7% e 72,6% para a topologia ressonante.

Research paper thumbnail of Robust Model Predictive Rotor Current Control of a DFIG Connected to a Distorted and Unbalanced Grid Driven by a Direct Matrix Converter

IEEE Transactions on Sustainable Energy, 2018

The DFIG has been widely used in the wind power industry due to its technical advantages. However... more The DFIG has been widely used in the wind power industry due to its technical advantages. However, current researches are being developed aiming at overcoming some of its drawbacks concerning reliability, efficiency and power quality. Since the wind farms are usually located at remote places, connected to weak grids, high reliability is required and some power quality issues deserve attention. This paper proposes a lowcomplexity, robust control of a DFIG driven by a direct matrix converter based on a model predictive rotor current control. The matrix converter is interesting due to the absence of the bulky and sensitive dc-link capacitors, leading to higher reliability. The predictive control is used to perform speed regulation. Moreover, this combination of converter and straightforward control is proven to be a robust technique that naturally compensates for stator current issues, which arises due to a low-power-quality grid voltage. Besides, a linear model of the proposed system is presented in order to be possible to use the linear-control-theory tools to execute the system control design. A processor-in-the-loop simulation is employed to validate the proposed control.

Research paper thumbnail of Projeto e Aplica��o de Filtros LCL+RC em Inversores Conectados � Rede

Proceedings XXII Congresso Brasileiro de Autom�tica, 2018

Research paper thumbnail of Opendss Modeling for Steady-State Analysis of Distributed Generation Control Techniques

Proceedings XXII Congresso Brasileiro de Autom�tica, 2018

O objetivo principal deste artigo e modelar na analise estatica os controladores de geracao em mi... more O objetivo principal deste artigo e modelar na analise estatica os controladores de geracao em microrredes atraves da simulacao no OPENDSS. Esses controladores foram projetados anteriormente em simuladores de transitorios de sistema de energia, como PSCAD / EMTDC, que permitem a analise de regime dinâmico com um certo nivel de custo computacional. Desta forma, a modelagem no OPENDSS deve reproduzir fielmente o desempenho estavel desses controladores para que o simulador possa ser usado para investigar altas penetracoes da geracao distribuida com custos computacionais relativamente reduzidos. Para este fim, inicialmente os esforcos se concentraram em determinar uma microrede a ser implementada; para em seguida, poder, atraves da analise estatica no OpenDSS, comparar os resultados, os quais confirmarao aqueles obtidos na analise dinâmica do controlador Sliding Droop, que permitira obter conclusoes do estado da rede em regime permanente antes de executar as simulacoes dinâmicas. Os resultados em regime permanente obtidos pela abordagem proposta foram validados pela simulacao dinâmica. Portanto a metodologia proposta neste artigo e promissora para analises de microrredes isoladas o controle Sliding Droop.

Research paper thumbnail of Design and computational modeling of fault current limiter topologies

The increase in demand for electric power and the insertion of a distributed generation led to th... more The increase in demand for electric power and the insertion of a distributed generation led to the rise of the short-circuit current in substations. Most of these Brazilian substations were designed decades ago, because of that their equipment may not support the new short-circuit current levels. To protect the installed equipment and avoid excessive costs replacing old devices, it is possible to install Fault Current Limiters (FCLs). This document is a report from an R&D project that evaluated FCL topologies considering real parameters in simulation from used equipment, concluding that the selected FCL topologies accomplished their technical objective. However, before implementing these topologies in the distribution system, one should consider the technical and economic feasibility of using semiconductor switching devices.

Research paper thumbnail of Detailed modelling and analysis of digital mho distance relay with single-pole operation

Acta Polytechnica, 2021

This paper introduces a methodology for modelling a digital admittance-type distance relay using ... more This paper introduces a methodology for modelling a digital admittance-type distance relay using PSCAD/EMTDC. The proposed distance relay was tested in a simulation of the Brazilian power grid with predetermined fault scenarios. The goal of this paper is to make a detailed evaluation of the mho distance relay. The main aspects include the correct operation of the distance relay, fault resistance effects on the mho characteristics, and the fault detection time of this relay. A new approach to analyse the fault detection time is presented, considering several simulated fault scenarios. The results demonstrate that the fault resistance influences the fault detection time and severely affects the distance relay’s general performance. The fault detection time is not constant. It varies within a time interval, considering different fault types, fault locations, and fault resistances. The confidence interval calculation provides a detailed range of the fault detection time, considering its...