Demercil S Oliveira - Academia.edu (original) (raw)
Papers by Demercil S Oliveira
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This paper presents the development of an interleaved bidirectional DC-DC converter with single-p... more This paper presents the development of an interleaved bidirectional DC-DC converter with single-phase high-frequency isolation associated with two different pulse width modulations (PWM), one for each power flow direction. The converter stages analysis, DC voltage gains expressions, and voltage/current stresses in CCM are presented. The proposed converter advantages are new modulation, the current ripple frequency and voltage in two ports is four times higher than the switching frequency, volume and weight reduction of passive elements, and balanced current distribution between the legs. Besides, the single-phase transformer that provides galvanic isolation between the DC bus and the battery or supercapacitor. An experimental prototype is implemented in the laboratory to validate the mathematical and theoretical analysis for both energy flow senses under the test conditions at converter-rated power 2.5kW, Low voltage side 180V, and high voltage side 380V.
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This paper presents a new three-port dc-dc high voltage gain boost converter based on the bidirec... more This paper presents a new three-port dc-dc high voltage gain boost converter based on the bidirectional version of the three-state switching cell for battery charging using photovoltaic (PV) modules in a single conversion stage. The presented converter is able to supply a 200-V dc link using a battery bank and a PV array and, depending on the solar irradiance level, it is also possible to charge the batteries by using a single-stage approach. Moreover, all switches of the converter are able to operate under zero voltage switching (ZVS) condition over a wide operation range. The static gain and experimental results on a 500-W laboratory prototype are presented in order to support the theoretical assumptions.
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PESC record, Jun 1, 2008
In this paper a soft-switching interleaved boost converter with high voltage gain is presented. T... more In this paper a soft-switching interleaved boost converter with high voltage gain is presented. The high voltage gain converter is far suitable for applications where a high step-up voltage is required, as in some renewable energy systems, which use, for example, photovoltaic panels and/or fuel cells. Besides, in order to guarantee small switching losses and, consequently, a high efficiency, a non- dissipative soft-switching cell with auxiliary commutation circuit is used. Thus, a large step-up voltage, low switching stress, small switching losses, and high efficiency are expected from this topology. In order to verify its effectiveness, experimental waveforms from the high voltage gain converter operating with hard-switching and soft-switching are compared. Also, waveforms from the soft-switching cell are presented and analyzed. Theoretical analysis, operation principle and topology details are also presented and studied.
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IEEE Transactions on Circuits and Systems II: Express Briefs, 2022
This brief addresses an overall circuit model to represent a novel generalized cascaded full-brid... more This brief addresses an overall circuit model to represent a novel generalized cascaded full-bridge (GCF) converter. The synthesis methodology of the GCF converter uses full-bridge sub-modules (SMs) combined with the interleaving and cascading concepts. The time-dependent equations represented in terms of current and voltage magnitudes are obtained. Thus, it is possible to derive a comprehensive control system approach from the model. An improved control strategy provides power balancing while using the circulating current to balance the dc-link voltages and ensuring proper current sharing. A small-scale laboratory prototype of a static synchronous compensator (STATCOM) rated at 2.2 kVA/311 V validates the theoretical assumptions and statements.
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2019 IEEE 15th Brazilian Power Electronics Conference and 5th IEEE Southern Power Electronics Conference (COBEP/SPEC), 2019
This paper proposes a multi-port, single-phase ac-dc converter with high frequency isolation and ... more This paper proposes a multi-port, single-phase ac-dc converter with high frequency isolation and bidirectional power flow capability, which is suitable for distributed generation, interconnecting various sources and loads, and controlling the power flow between them in an integrated conversion stage. Three-state switching cells and interleaved converters are employed in order to achieve high power processing capability. In order to verify the feasibility of this topology, it is presented the principle of operation, theoretical analysis, control strategy and simulation waveforms. Some experimental results are presented for a 1 kW laboratory prototype under construction.
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2018 13th IEEE International Conference on Industry Applications (INDUSCON), 2018
This paper presents an interleaved two-switch Flyback converter operating in discontinuous conduc... more This paper presents an interleaved two-switch Flyback converter operating in discontinuous conduction mode (DCM) for On-line Uninterruptable Power Supply (UPS) applications, capable of providing power factor correction (PFC) to a single-phase rectifier. It has as advantages: high power factor, balanced voltage and current shared through the semiconductors, which provides higher power processing, and a simple voltage control strategy. For the closed-loop control design, all parameters of the proposed converter are referred to the transformer primary side in order to obtain an equivalent non-isolated Buck-Boost converter, whose transfer functions are already consolidated in the technical literature. To verify the operation of the proposed topology, simulation results are provided with the following specifications: mains voltage input 220 V +/- 20% and frequency of 60 Hz, 250 V output voltage and output power rated at 1 kW.
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International audienc
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2018 IEEE Applied Power Electronics Conference and Exposition (APEC), 2018
This paper proposes the use of the three-phase single-stage bidirectional ac-dc converter with hi... more This paper proposes the use of the three-phase single-stage bidirectional ac-dc converter with high frequency isolation as a multiport power converter. The presented topology is suitable for the new concept of distributed generation, or smart-grids, interconnecting various sources and loads, controlling the power flow between them, with only one converter. The phase-shift angle between the primary and secondary side controls the power flow of the converter which is based on the three-phase version of the dual active bridge and associated with the three-state-switching cell. Therefore, a center tap is used in the secondary windings as well as a modified modulation in order to avoid the low frequency content in the third port.
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2018 13th IEEE International Conference on Industry Applications (INDUSCON), 2018
This paper presents a multi-port, single-phase isolated converter applied to residential microgen... more This paper presents a multi-port, single-phase isolated converter applied to residential microgeneration, employing one ac port and multiple dc ones. The proposed system consists of solar photovoltaic (PV) modules, a battery bank, and two full-bridge converters working as a single integrated structure. A strategy is also proposed aiming at improved utilization of the ac utility grid through the power flow control between the electronic converter ports, which is performed according to some system parameters such as power levels generated by the PV modules and weather conditions. In order to achieve high power processing capability with low losses at high frequency, three-state switching cells and interleaved converters are employed. The main characteristics and operating stages regarding the system are introduced. Simulation results are presented to validate the control strategy, while the rms ac voltage is 220 V (60 Hz) and the voltages across the dc are 400 V, 96 V and 48 V, considering that the switching frequency is 50 kHz and the rated power is 1500 W.
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IEEE Transactions on Industrial Electronics, 2021
This work investigates a generalized cascaded full-bridge (GCF) concept, which uses a full-bridge... more This work investigates a generalized cascaded full-bridge (GCF) concept, which uses a full-bridge converter as a basic submodule, combined with the interleaving and cascading techniques. When compared with the traditional cascaded full-bridge (CFB) converter, the GCF topologies present the advantages of reduced current and voltage stresses on the semiconductors, and flexible design. Thereby, the resulting structures become an alternative solution for high-power applications involving high current and high voltage levels. The generalized analysis involving design guidelines for the synthesis of each topology, the system model, and possible modulation strategies are described in detail. A comparative study with the CFB-based topologies shows that the introduced structures are capable of achieving improved performance in terms of reduced losses in the power semiconductors and lower device count. A small-scale laboratory prototype of a static synchronous compensator rated at 2.2 kVA/311 V is implemented to validate the design assumptions considering the steady-state and transient performances.
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Bookmarks Related papers MentionsView impact
Iet Power Electronics, 2015
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IEEE Transactions on Power Electronics, 2014
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IEEE Transactions on Power Electronics, Aug 1, 2011
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Conference proceedings, Feb 1, 2008
ABSTRACT
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ABSTRACT
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IEEE Transactions on Industry Applications, Sep 1, 2018
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IEEE Transactions on Power Electronics, Nov 1, 2010
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International Journal of Circuit Theory and Applications, Apr 19, 2023
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
This paper presents the development of an interleaved bidirectional DC-DC converter with single-p... more This paper presents the development of an interleaved bidirectional DC-DC converter with single-phase high-frequency isolation associated with two different pulse width modulations (PWM), one for each power flow direction. The converter stages analysis, DC voltage gains expressions, and voltage/current stresses in CCM are presented. The proposed converter advantages are new modulation, the current ripple frequency and voltage in two ports is four times higher than the switching frequency, volume and weight reduction of passive elements, and balanced current distribution between the legs. Besides, the single-phase transformer that provides galvanic isolation between the DC bus and the battery or supercapacitor. An experimental prototype is implemented in the laboratory to validate the mathematical and theoretical analysis for both energy flow senses under the test conditions at converter-rated power 2.5kW, Low voltage side 180V, and high voltage side 380V.
Bookmarks Related papers MentionsView impact
This paper presents a new three-port dc-dc high voltage gain boost converter based on the bidirec... more This paper presents a new three-port dc-dc high voltage gain boost converter based on the bidirectional version of the three-state switching cell for battery charging using photovoltaic (PV) modules in a single conversion stage. The presented converter is able to supply a 200-V dc link using a battery bank and a PV array and, depending on the solar irradiance level, it is also possible to charge the batteries by using a single-stage approach. Moreover, all switches of the converter are able to operate under zero voltage switching (ZVS) condition over a wide operation range. The static gain and experimental results on a 500-W laboratory prototype are presented in order to support the theoretical assumptions.
Bookmarks Related papers MentionsView impact
PESC record, Jun 1, 2008
In this paper a soft-switching interleaved boost converter with high voltage gain is presented. T... more In this paper a soft-switching interleaved boost converter with high voltage gain is presented. The high voltage gain converter is far suitable for applications where a high step-up voltage is required, as in some renewable energy systems, which use, for example, photovoltaic panels and/or fuel cells. Besides, in order to guarantee small switching losses and, consequently, a high efficiency, a non- dissipative soft-switching cell with auxiliary commutation circuit is used. Thus, a large step-up voltage, low switching stress, small switching losses, and high efficiency are expected from this topology. In order to verify its effectiveness, experimental waveforms from the high voltage gain converter operating with hard-switching and soft-switching are compared. Also, waveforms from the soft-switching cell are presented and analyzed. Theoretical analysis, operation principle and topology details are also presented and studied.
Bookmarks Related papers MentionsView impact
IEEE Transactions on Circuits and Systems II: Express Briefs, 2022
This brief addresses an overall circuit model to represent a novel generalized cascaded full-brid... more This brief addresses an overall circuit model to represent a novel generalized cascaded full-bridge (GCF) converter. The synthesis methodology of the GCF converter uses full-bridge sub-modules (SMs) combined with the interleaving and cascading concepts. The time-dependent equations represented in terms of current and voltage magnitudes are obtained. Thus, it is possible to derive a comprehensive control system approach from the model. An improved control strategy provides power balancing while using the circulating current to balance the dc-link voltages and ensuring proper current sharing. A small-scale laboratory prototype of a static synchronous compensator (STATCOM) rated at 2.2 kVA/311 V validates the theoretical assumptions and statements.
Bookmarks Related papers MentionsView impact
2019 IEEE 15th Brazilian Power Electronics Conference and 5th IEEE Southern Power Electronics Conference (COBEP/SPEC), 2019
This paper proposes a multi-port, single-phase ac-dc converter with high frequency isolation and ... more This paper proposes a multi-port, single-phase ac-dc converter with high frequency isolation and bidirectional power flow capability, which is suitable for distributed generation, interconnecting various sources and loads, and controlling the power flow between them in an integrated conversion stage. Three-state switching cells and interleaved converters are employed in order to achieve high power processing capability. In order to verify the feasibility of this topology, it is presented the principle of operation, theoretical analysis, control strategy and simulation waveforms. Some experimental results are presented for a 1 kW laboratory prototype under construction.
Bookmarks Related papers MentionsView impact
2018 13th IEEE International Conference on Industry Applications (INDUSCON), 2018
This paper presents an interleaved two-switch Flyback converter operating in discontinuous conduc... more This paper presents an interleaved two-switch Flyback converter operating in discontinuous conduction mode (DCM) for On-line Uninterruptable Power Supply (UPS) applications, capable of providing power factor correction (PFC) to a single-phase rectifier. It has as advantages: high power factor, balanced voltage and current shared through the semiconductors, which provides higher power processing, and a simple voltage control strategy. For the closed-loop control design, all parameters of the proposed converter are referred to the transformer primary side in order to obtain an equivalent non-isolated Buck-Boost converter, whose transfer functions are already consolidated in the technical literature. To verify the operation of the proposed topology, simulation results are provided with the following specifications: mains voltage input 220 V +/- 20% and frequency of 60 Hz, 250 V output voltage and output power rated at 1 kW.
Bookmarks Related papers MentionsView impact
International audienc
Bookmarks Related papers MentionsView impact
2018 IEEE Applied Power Electronics Conference and Exposition (APEC), 2018
This paper proposes the use of the three-phase single-stage bidirectional ac-dc converter with hi... more This paper proposes the use of the three-phase single-stage bidirectional ac-dc converter with high frequency isolation as a multiport power converter. The presented topology is suitable for the new concept of distributed generation, or smart-grids, interconnecting various sources and loads, controlling the power flow between them, with only one converter. The phase-shift angle between the primary and secondary side controls the power flow of the converter which is based on the three-phase version of the dual active bridge and associated with the three-state-switching cell. Therefore, a center tap is used in the secondary windings as well as a modified modulation in order to avoid the low frequency content in the third port.
Bookmarks Related papers MentionsView impact
2018 13th IEEE International Conference on Industry Applications (INDUSCON), 2018
This paper presents a multi-port, single-phase isolated converter applied to residential microgen... more This paper presents a multi-port, single-phase isolated converter applied to residential microgeneration, employing one ac port and multiple dc ones. The proposed system consists of solar photovoltaic (PV) modules, a battery bank, and two full-bridge converters working as a single integrated structure. A strategy is also proposed aiming at improved utilization of the ac utility grid through the power flow control between the electronic converter ports, which is performed according to some system parameters such as power levels generated by the PV modules and weather conditions. In order to achieve high power processing capability with low losses at high frequency, three-state switching cells and interleaved converters are employed. The main characteristics and operating stages regarding the system are introduced. Simulation results are presented to validate the control strategy, while the rms ac voltage is 220 V (60 Hz) and the voltages across the dc are 400 V, 96 V and 48 V, considering that the switching frequency is 50 kHz and the rated power is 1500 W.
Bookmarks Related papers MentionsView impact
IEEE Transactions on Industrial Electronics, 2021
This work investigates a generalized cascaded full-bridge (GCF) concept, which uses a full-bridge... more This work investigates a generalized cascaded full-bridge (GCF) concept, which uses a full-bridge converter as a basic submodule, combined with the interleaving and cascading techniques. When compared with the traditional cascaded full-bridge (CFB) converter, the GCF topologies present the advantages of reduced current and voltage stresses on the semiconductors, and flexible design. Thereby, the resulting structures become an alternative solution for high-power applications involving high current and high voltage levels. The generalized analysis involving design guidelines for the synthesis of each topology, the system model, and possible modulation strategies are described in detail. A comparative study with the CFB-based topologies shows that the introduced structures are capable of achieving improved performance in terms of reduced losses in the power semiconductors and lower device count. A small-scale laboratory prototype of a static synchronous compensator rated at 2.2 kVA/311 V is implemented to validate the design assumptions considering the steady-state and transient performances.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Iet Power Electronics, 2015
Bookmarks Related papers MentionsView impact
IEEE Transactions on Power Electronics, 2014
Bookmarks Related papers MentionsView impact
IEEE Transactions on Power Electronics, Aug 1, 2011
Bookmarks Related papers MentionsView impact
Conference proceedings, Feb 1, 2008
ABSTRACT
Bookmarks Related papers MentionsView impact
ABSTRACT
Bookmarks Related papers MentionsView impact
IEEE Transactions on Industry Applications, Sep 1, 2018
Bookmarks Related papers MentionsView impact
IEEE Transactions on Power Electronics, Nov 1, 2010
Bookmarks Related papers MentionsView impact
International Journal of Circuit Theory and Applications, Apr 19, 2023
Bookmarks Related papers MentionsView impact