juan balestero | Universidade Estadual Paulista "Júlio de Mesquita Filho" (original) (raw)

Papers by juan balestero

International Journal of Electronics, Aug 25, 2015

ABSTRACT It is well known that there is an increasing demand for bidirectional DC–DC converters f... more ABSTRACT It is well known that there is an increasing demand for bidirectional DC–DC converters for applications that range from renewable energy sources to electric vehicles. Within this context, this work proposes novel DC–DC converter topologies that use the three-state switching cell (3SSC), whose well-known advantages over conventional existing structures are ability to operate at high current levels, while current sharing is maintained by a high frequency transformer; reduction of cost and dimensions of magnetics; improved distribution of losses, with consequent increase of global efficiency and reduction of cost associated to the need of semiconductors with lower current ratings. Three distinct topologies can be derived from the 3SSC: one DC–DC converter with reversible current characteristic able to operate in the first and second quadrants; one DC–DC converter with reversible voltage characteristic able to operate in the first and third quadrants and one DC–DC converter with reversible current and voltage characteristics able to operate in four quadrants. Only the topology with bidirectional current characteristic is analysed in detail in terms of the operating stages in both nonoverlapping and overlapping modes, while the design procedure of the power stage elements is obtained. In order to validate the theoretical assumptions, an experimental prototype is also implemented, so that relevant issues can be properly discussed.

Eletrônica de Potência, Feb 1, 2013

This work presents the detailed analysis of the dc-dc nonisolated buck converter based on the thr... more This work presents the detailed analysis of the dc-dc nonisolated buck converter based on the threestate switching cell operating in overlapping mode, which occurs when the duty cycle of the active switches is higher than 0.5. Only part of the load power is processed by the active switches due to the use of the autotransformer, thus reducing the peak current through the switches to half of the load current, as higher power levels can then be achieved by the proposed topology. The volume of reactive elements i.e. inductors and capacitors is also decreased since the ripple frequency of the output voltage is twice the switching frequency. Due to the intrinsic characteristics of the topology, total losses are distributed among all semiconductors. Another advantage of this converter is the reduced region for discontinuous conduction mode when compared to the conventional buck converter as demonstrated by the static gain plot. Besides, the input current is continuous and the ripple current is reduced, what is not verified in the classical buck converter. The theoretical approach is detailed through qualitative and quantitative analyses, design procedure, and a comparison with similar topologies. Finally, an experimental prototype rated at 1 kW is implemented, while the main experimental results are presented and adequately discussed to clearly identify its claimed advantages.

IEEE Transactions on Power Electronics, 2013

ABSTRACT

IEEE Transactions on Industrial Electronics, Mar 1, 2012

The need for solid-state ac-dc converters to improve power quality in terms of power factor corre... more The need for solid-state ac-dc converters to improve power quality in terms of power factor correction, reduced total harmonic distortion at input ac mains, and precisely regulated dc output has motivated the investigation of several topologies based on classical converters such as buck, boost, and buck-boost converters. Boost converters operating in continuous-conduction mode have become particularly popular because reduced electro-

Eletrônica de Potência, May 1, 2012

This paper introduces a bridgeless boost converter based on the three-state switching cell for PF... more This paper introduces a bridgeless boost converter based on the three-state switching cell for PFC (power factor correction) applications, whose distinct advantages are reduced conduction losses with the use of magnetic elements with minimized size, weight, and volume. The approach also employs the principle of interleaved converters, as it can be extended to a generic number of legs per winding of the autotransformers and high power levels. The theoretical analysis of the proposed converter is developed, while a comparison with the conventional boost converter is also performed. An experimental prototype rated at 1 kW is implemented to validate the proposal, as relevant issues regarding the novel converter are discussed. 1 I. INTRODUCTION

The representation of transmission lines in modal domain is widely known. However, there is nothi... more The representation of transmission lines in modal domain is widely known. However, there is nothing in the literature regarding the behavior of loads in the modal domain connected to the receiver of a transmission line. In this article we will show how the transmission lines are represented in the modal domain, considering the presence of connected loads in their terminals. The results show that balanced loads with or without mutual coupling can be represented in the modal domain as uncoupled single-phase loads that are connected at the receiving terminal of each line propagation mode. When it comes to unbalanced loads it is found that they are also represented by single phase loads. However, in the case of unbalanced loads, there is a coupling between these single-phase loads. The study allows the understanding of how transmission lines with loads are represented, in the modal domain, in software that performs simulations of electromagnetic transients in electrical power systems (A...

International Journal of Electronics, 2015

ABSTRACT It is well known that there is an increasing demand for bidirectional DC–DC converters f... more ABSTRACT It is well known that there is an increasing demand for bidirectional DC–DC converters for applications that range from renewable energy sources to electric vehicles. Within this context, this work proposes novel DC–DC converter topologies that use the three-state switching cell (3SSC), whose well-known advantages over conventional existing structures are ability to operate at high current levels, while current sharing is maintained by a high frequency transformer; reduction of cost and dimensions of magnetics; improved distribution of losses, with consequent increase of global efficiency and reduction of cost associated to the need of semiconductors with lower current ratings. Three distinct topologies can be derived from the 3SSC: one DC–DC converter with reversible current characteristic able to operate in the first and second quadrants; one DC–DC converter with reversible voltage characteristic able to operate in the first and third quadrants and one DC–DC converter with reversible current and voltage characteristics able to operate in four quadrants. Only the topology with bidirectional current characteristic is analysed in detail in terms of the operating stages in both nonoverlapping and overlapping modes, while the design procedure of the power stage elements is obtained. In order to validate the theoretical assumptions, an experimental prototype is also implemented, so that relevant issues can be properly discussed.

IEEE Transactions on Power Electronics, 2013

ABSTRACT

IEEE Transactions on Industrial Electronics, 2012

The need for solid-state ac-dc converters to improve power quality in terms of power factor corre... more The need for solid-state ac-dc converters to improve power quality in terms of power factor correction, reduced total harmonic distortion at input ac mains, and precisely regulated dc output has motivated the investigation of several topologies based on classical converters such as buck, boost, and buck-boost converters. Boost converters operating in continuous-conduction mode have become particularly popular because reduced electro-

IEEE Access

This work presents a transmission line model for simulating electromagnetic transients directly i... more This work presents a transmission line model for simulating electromagnetic transients directly in the time domain. For this purpose, the exact equivalent π-circuit is used, which represents the line taking into account its distributed and frequency-dependent parameters. The admittances that constitute the exact equivalent π-circuit are approximated by rational functions using the vector fitting technique. Then, for each admittance, an electrical circuit is synthesized, consisting of an association of discrete elements (resistors, inductors, and capacitors) aiming at modeling the transmission line, thus allowing its use in any circuit simulation software and the eventual connection of nonlinear elements. From the simulation results, it is reasonable to state that the proposed model is a feasible representation, which aggregates the same features of the exact equivalent π-circuit directly in the time domain, not only in steady state, but mainly during transients and also without the need for using convolutions, as well as inverse Laplace or Fourier transforms. INDEX TERMS Electromagnetic transients, transmission line model, time-domain analysis, vector fitting.

International Journal of Electronics, 2013

ABSTRACT

Eletrônica de Potência, 2013

This work presents the detailed analysis of the dc-dc nonisolated buck converter based on the thr... more This work presents the detailed analysis of the dc-dc nonisolated buck converter based on the threestate switching cell operating in overlapping mode, which occurs when the duty cycle of the active switches is higher than 0.5. Only part of the load power is processed by the active switches due to the use of the autotransformer, thus reducing the peak current through the switches to half of the load current, as higher power levels can then be achieved by the proposed topology. The volume of reactive elements i.e. inductors and capacitors is also decreased since the ripple frequency of the output voltage is twice the switching frequency. Due to the intrinsic characteristics of the topology, total losses are distributed among all semiconductors. Another advantage of this converter is the reduced region for discontinuous conduction mode when compared to the conventional buck converter as demonstrated by the static gain plot. Besides, the input current is continuous and the ripple current is reduced, what is not verified in the classical buck converter. The theoretical approach is detailed through qualitative and quantitative analyses, design procedure, and a comparison with similar topologies. Finally, an experimental prototype rated at 1 kW is implemented, while the main experimental results are presented and adequately discussed to clearly identify its claimed advantages.

Normal 0 21 false false false MicrosoftInternetExplorer4 Este artigo descreve o desenvolvimento d... more Normal 0 21 false false false MicrosoftInternetExplorer4 Este artigo descreve o desenvolvimento de um sistema para otimizar a operacao de sistemas de geracao fotovoltaicos, cuja potencia de saida em uma carga variavel e o parâmetro a ser otimizado. Levando isto em conta, este trabalho, realizado no Instituo Federal de Santa Catarina, Campus Chapeco, apresenta a implementacao de um conversor de busca do ponto de maxima potencia na carga-teste, podendo servir como ponto de partida para uma futura implementacao de um inversor para paineis fotovoltaicos. Sao apresentados resultados de testes iniciais com o algoritmo desenvolvido, avaliando as respostas do mesmo frente as variacoes apresentadas. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-paginati...

Eletrônica de Potência, May 1, 2012

This paper introduces a bridgeless boost converter based on the three-state switching cell for PF... more This paper introduces a bridgeless boost converter based on the three-state switching cell for PFC (power factor correction) applications, whose distinct advantages are reduced conduction losses with the use of magnetic elements with minimized size, weight, and volume. The approach also employs the principle of interleaved converters, as it can be extended to a generic number of legs per winding of the autotransformers and high power levels. The theoretical analysis of the proposed converter is developed, while a comparison with the conventional boost converter is also performed. An experimental prototype rated at 1 kW is implemented to validate the proposal, as relevant issues regarding the novel converter are discussed. 1 I. INTRODUCTION

IEEE Transactions on Industrial Electronics, 2012

The need for solid-state ac-dc converters to improve power quality in terms of power factor corre... more The need for solid-state ac-dc converters to improve power quality in terms of power factor correction, reduced total harmonic distortion at input ac mains, and precisely regulated dc output has motivated the investigation of several topologies based on classical converters such as buck, boost, and buck-boost converters. Boost converters operating in continuous-conduction mode have become particularly popular because reduced electromagnetic interference levels result from their utilization. Within this context, this paper introduces a bridgeless boost converter based on a three-state switching cell (3SSC), whose distinct advantages are reduced conduction losses with the use of magnetic elements with minimized size, weight, and volume. The approach also employs the principle of interleaved converters, as it can be extended to a generic number of legs per winding of the autotransformers and high power levels. A literature review of boost converters based on the 3SSC is initially prese...

International Journal of Electronics, Aug 25, 2015

ABSTRACT It is well known that there is an increasing demand for bidirectional DC–DC converters f... more ABSTRACT It is well known that there is an increasing demand for bidirectional DC–DC converters for applications that range from renewable energy sources to electric vehicles. Within this context, this work proposes novel DC–DC converter topologies that use the three-state switching cell (3SSC), whose well-known advantages over conventional existing structures are ability to operate at high current levels, while current sharing is maintained by a high frequency transformer; reduction of cost and dimensions of magnetics; improved distribution of losses, with consequent increase of global efficiency and reduction of cost associated to the need of semiconductors with lower current ratings. Three distinct topologies can be derived from the 3SSC: one DC–DC converter with reversible current characteristic able to operate in the first and second quadrants; one DC–DC converter with reversible voltage characteristic able to operate in the first and third quadrants and one DC–DC converter with reversible current and voltage characteristics able to operate in four quadrants. Only the topology with bidirectional current characteristic is analysed in detail in terms of the operating stages in both nonoverlapping and overlapping modes, while the design procedure of the power stage elements is obtained. In order to validate the theoretical assumptions, an experimental prototype is also implemented, so that relevant issues can be properly discussed.

Eletrônica de Potência, Feb 1, 2013

This work presents the detailed analysis of the dc-dc nonisolated buck converter based on the thr... more This work presents the detailed analysis of the dc-dc nonisolated buck converter based on the threestate switching cell operating in overlapping mode, which occurs when the duty cycle of the active switches is higher than 0.5. Only part of the load power is processed by the active switches due to the use of the autotransformer, thus reducing the peak current through the switches to half of the load current, as higher power levels can then be achieved by the proposed topology. The volume of reactive elements i.e. inductors and capacitors is also decreased since the ripple frequency of the output voltage is twice the switching frequency. Due to the intrinsic characteristics of the topology, total losses are distributed among all semiconductors. Another advantage of this converter is the reduced region for discontinuous conduction mode when compared to the conventional buck converter as demonstrated by the static gain plot. Besides, the input current is continuous and the ripple current is reduced, what is not verified in the classical buck converter. The theoretical approach is detailed through qualitative and quantitative analyses, design procedure, and a comparison with similar topologies. Finally, an experimental prototype rated at 1 kW is implemented, while the main experimental results are presented and adequately discussed to clearly identify its claimed advantages.

IEEE Transactions on Power Electronics, 2013

ABSTRACT

IEEE Transactions on Industrial Electronics, Mar 1, 2012

The need for solid-state ac-dc converters to improve power quality in terms of power factor corre... more The need for solid-state ac-dc converters to improve power quality in terms of power factor correction, reduced total harmonic distortion at input ac mains, and precisely regulated dc output has motivated the investigation of several topologies based on classical converters such as buck, boost, and buck-boost converters. Boost converters operating in continuous-conduction mode have become particularly popular because reduced electro-

Eletrônica de Potência, May 1, 2012

This paper introduces a bridgeless boost converter based on the three-state switching cell for PF... more This paper introduces a bridgeless boost converter based on the three-state switching cell for PFC (power factor correction) applications, whose distinct advantages are reduced conduction losses with the use of magnetic elements with minimized size, weight, and volume. The approach also employs the principle of interleaved converters, as it can be extended to a generic number of legs per winding of the autotransformers and high power levels. The theoretical analysis of the proposed converter is developed, while a comparison with the conventional boost converter is also performed. An experimental prototype rated at 1 kW is implemented to validate the proposal, as relevant issues regarding the novel converter are discussed. 1 I. INTRODUCTION

The representation of transmission lines in modal domain is widely known. However, there is nothi... more The representation of transmission lines in modal domain is widely known. However, there is nothing in the literature regarding the behavior of loads in the modal domain connected to the receiver of a transmission line. In this article we will show how the transmission lines are represented in the modal domain, considering the presence of connected loads in their terminals. The results show that balanced loads with or without mutual coupling can be represented in the modal domain as uncoupled single-phase loads that are connected at the receiving terminal of each line propagation mode. When it comes to unbalanced loads it is found that they are also represented by single phase loads. However, in the case of unbalanced loads, there is a coupling between these single-phase loads. The study allows the understanding of how transmission lines with loads are represented, in the modal domain, in software that performs simulations of electromagnetic transients in electrical power systems (A...

International Journal of Electronics, 2015

ABSTRACT It is well known that there is an increasing demand for bidirectional DC–DC converters f... more ABSTRACT It is well known that there is an increasing demand for bidirectional DC–DC converters for applications that range from renewable energy sources to electric vehicles. Within this context, this work proposes novel DC–DC converter topologies that use the three-state switching cell (3SSC), whose well-known advantages over conventional existing structures are ability to operate at high current levels, while current sharing is maintained by a high frequency transformer; reduction of cost and dimensions of magnetics; improved distribution of losses, with consequent increase of global efficiency and reduction of cost associated to the need of semiconductors with lower current ratings. Three distinct topologies can be derived from the 3SSC: one DC–DC converter with reversible current characteristic able to operate in the first and second quadrants; one DC–DC converter with reversible voltage characteristic able to operate in the first and third quadrants and one DC–DC converter with reversible current and voltage characteristics able to operate in four quadrants. Only the topology with bidirectional current characteristic is analysed in detail in terms of the operating stages in both nonoverlapping and overlapping modes, while the design procedure of the power stage elements is obtained. In order to validate the theoretical assumptions, an experimental prototype is also implemented, so that relevant issues can be properly discussed.

IEEE Transactions on Power Electronics, 2013

ABSTRACT

IEEE Transactions on Industrial Electronics, 2012

The need for solid-state ac-dc converters to improve power quality in terms of power factor corre... more The need for solid-state ac-dc converters to improve power quality in terms of power factor correction, reduced total harmonic distortion at input ac mains, and precisely regulated dc output has motivated the investigation of several topologies based on classical converters such as buck, boost, and buck-boost converters. Boost converters operating in continuous-conduction mode have become particularly popular because reduced electro-

IEEE Access

This work presents a transmission line model for simulating electromagnetic transients directly i... more This work presents a transmission line model for simulating electromagnetic transients directly in the time domain. For this purpose, the exact equivalent π-circuit is used, which represents the line taking into account its distributed and frequency-dependent parameters. The admittances that constitute the exact equivalent π-circuit are approximated by rational functions using the vector fitting technique. Then, for each admittance, an electrical circuit is synthesized, consisting of an association of discrete elements (resistors, inductors, and capacitors) aiming at modeling the transmission line, thus allowing its use in any circuit simulation software and the eventual connection of nonlinear elements. From the simulation results, it is reasonable to state that the proposed model is a feasible representation, which aggregates the same features of the exact equivalent π-circuit directly in the time domain, not only in steady state, but mainly during transients and also without the need for using convolutions, as well as inverse Laplace or Fourier transforms. INDEX TERMS Electromagnetic transients, transmission line model, time-domain analysis, vector fitting.

International Journal of Electronics, 2013

ABSTRACT

Eletrônica de Potência, 2013

This work presents the detailed analysis of the dc-dc nonisolated buck converter based on the thr... more This work presents the detailed analysis of the dc-dc nonisolated buck converter based on the threestate switching cell operating in overlapping mode, which occurs when the duty cycle of the active switches is higher than 0.5. Only part of the load power is processed by the active switches due to the use of the autotransformer, thus reducing the peak current through the switches to half of the load current, as higher power levels can then be achieved by the proposed topology. The volume of reactive elements i.e. inductors and capacitors is also decreased since the ripple frequency of the output voltage is twice the switching frequency. Due to the intrinsic characteristics of the topology, total losses are distributed among all semiconductors. Another advantage of this converter is the reduced region for discontinuous conduction mode when compared to the conventional buck converter as demonstrated by the static gain plot. Besides, the input current is continuous and the ripple current is reduced, what is not verified in the classical buck converter. The theoretical approach is detailed through qualitative and quantitative analyses, design procedure, and a comparison with similar topologies. Finally, an experimental prototype rated at 1 kW is implemented, while the main experimental results are presented and adequately discussed to clearly identify its claimed advantages.

Normal 0 21 false false false MicrosoftInternetExplorer4 Este artigo descreve o desenvolvimento d... more Normal 0 21 false false false MicrosoftInternetExplorer4 Este artigo descreve o desenvolvimento de um sistema para otimizar a operacao de sistemas de geracao fotovoltaicos, cuja potencia de saida em uma carga variavel e o parâmetro a ser otimizado. Levando isto em conta, este trabalho, realizado no Instituo Federal de Santa Catarina, Campus Chapeco, apresenta a implementacao de um conversor de busca do ponto de maxima potencia na carga-teste, podendo servir como ponto de partida para uma futura implementacao de um inversor para paineis fotovoltaicos. Sao apresentados resultados de testes iniciais com o algoritmo desenvolvido, avaliando as respostas do mesmo frente as variacoes apresentadas. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-paginati...

Eletrônica de Potência, May 1, 2012

This paper introduces a bridgeless boost converter based on the three-state switching cell for PF... more This paper introduces a bridgeless boost converter based on the three-state switching cell for PFC (power factor correction) applications, whose distinct advantages are reduced conduction losses with the use of magnetic elements with minimized size, weight, and volume. The approach also employs the principle of interleaved converters, as it can be extended to a generic number of legs per winding of the autotransformers and high power levels. The theoretical analysis of the proposed converter is developed, while a comparison with the conventional boost converter is also performed. An experimental prototype rated at 1 kW is implemented to validate the proposal, as relevant issues regarding the novel converter are discussed. 1 I. INTRODUCTION

IEEE Transactions on Industrial Electronics, 2012

The need for solid-state ac-dc converters to improve power quality in terms of power factor corre... more The need for solid-state ac-dc converters to improve power quality in terms of power factor correction, reduced total harmonic distortion at input ac mains, and precisely regulated dc output has motivated the investigation of several topologies based on classical converters such as buck, boost, and buck-boost converters. Boost converters operating in continuous-conduction mode have become particularly popular because reduced electromagnetic interference levels result from their utilization. Within this context, this paper introduces a bridgeless boost converter based on a three-state switching cell (3SSC), whose distinct advantages are reduced conduction losses with the use of magnetic elements with minimized size, weight, and volume. The approach also employs the principle of interleaved converters, as it can be extended to a generic number of legs per winding of the autotransformers and high power levels. A literature review of boost converters based on the 3SSC is initially prese...