EPE Association: EPE 2021 - Resonant Converters

EPE 2021 - Resonant Converters
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2021 ECCE Europe - Conference > EPE 2021 - Topic 02: Power Converter Topologies and Design > EPE 2021 - Resonant Converters

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   Analysis and Design of a Single-Phase Half-Bridge Rectifier/Inverter with an Active Resonant DC Bus Voltage balancer
By Zoran MILETIC [View]
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Abstract: This paper presents the analysis and design of the single-phase half bridge rectifier with an active voltage DC bus balancer (ARVB). Impact of the power ripple on the DC bus of the ordinary rectifier/inverter and the rectifier/inverter with the ARVB is examined. It will be shown that with the ARVB, the volume and size of the DC bus; hence the converter can be significantly reduced, since the ARVB eliminates fundamental and the most significant component of the DC bus current.

   Frequency-Doubler Modulation for Reduced Junction Temperatures for LLC Resonant Converters Operated in Half-Bridge Configuration
By Philipp REHLAENDER [View]
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Abstract: LLC resonant converters are typically unsuitable to be applied for wide voltage-transfer ratio applications. With a full-bridge inverter, however, they can be operated in a variety of different modulations. Most notably, by permanently turning on one MOSFET and turning off the other MOSFET of the same bridge leg, the LLC can be operated in half-bridge configuration reducing the gain by a factor of two. The resonant capacitor is hereby charged to an average voltage of half the input voltage. In this modulation, however, the switch that is permanently turned on is stressed by the complete resonant current while exhibiting no switching losses. This paper proves that the frequency-doubler modulation can better balance the losses among all MOSFETs and should be the preferred mode of operation favored over the conventional half-bridge modulation. This paper analyzes the beneficial loss distribution, proposes an on-the-fly morphing modulation and discusses potential operating strategies to further reduce the junction temperature. Furthermore, it is shown that this modulation can also be altered to achieve the asymmetrical LLC operation. Experimental measurement results show that the modulation results in a substantial decrease of the maximum MOSFET temperature and shows that the converter can be smoothly transitioned during operation from full-bridge modulation to the frequency-doubler half-bridge operation and back.

   Resonant Switched Capacitor DC-DC converter (RSCC) for Data Center applications
By Haitao CHEN [View]
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Abstract: With rapid technological advancement and huge consumer requirements for cloud complex computing, Internet of things, big data storage and owing to various other increased consumer needs there comes more and more strain on the data centers. Furthermore, data centers too, have undergone through significant evolution in the recent years which has led their power losses to grow enormous and the CO2 emission as well has become significant. To provide a solution to an ever-growing stress on data centers and their huge power losses, in this paper a non-isolated, non-regulated, fixed voltage conversion ratio (4:1) step-down, DC-DC converter i.e. Resonant switched capacitor DC-DC converter (RSCC) for data center applications are proposed, presented and designed for achieving high efficiency and high-power density. Simulation validation and hardware design is done for the production of a hardware prototype. Moreover, the design methodology of resonant switched capacitor DC-DC converter prototype is presented.

   Superior usage of the Bidirectional Isolated Series-Resonant AC/DC Converter
By Remco BONTEN [View]
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Abstract: Conventionally, grid-connected isolated AC/DC conversion is realized through a two-stage approach,resulting in an increased number of (magnetic) components and thus a cost-inefficient solution.Therefore, this paper focusses on an extension of a recently proposed control strategy, i.e.bidirectional charge control, for a bidirectional, isolated, series-resonant DC/DC converter. Bidirectionalcharge control targets a predefined charge displacement between two consecutive zerocrossingsof the resonant current and calculates the required switching levels for the semiconductorswitches accordingly. These switching levels are defined as a function of the charge differenceacross the resonant capacitor, realizing dynamic, bidirectional operation of the series-resonant converterwhile guaranteeing zero-voltage switching of all switches. In order to maintain grid quality,grid-tied converters are verified for compliance regarding their harmonic current emissions and totalharmonic distortion (THD). Therefore, power-factor correction (PFC) is a requirement for each ofthese converters. To achieve power-factor correction, a phase-locked loop is implemented with anouter control loop to realize sinusoidal grid-current waveforms and, as a result, low harmonic currentemissions that do comply to the standards and a low THD. The discussed control algorithm and thelinearization are verified through simulation for a 3kW electric vehicle battery charger to connect tothe single-phase grid. Nonetheless, wide primary, grid voltage and wide secondary, electric vehiclebattery voltage ranges have been shown applicable with bidirectional charge control. Although thesimulations show very promising results, realization on a prototype is recommended to validate thetheoretical analysis and prove the robustness of the proposed control strategy.

EPE 2021 - Resonant Converters
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2021 ECCE Europe - Conference > EPE 2021 - Topic 02: Power Converter Topologies and Design > EPE 2021 - Resonant Converters
	[return to parent folder]

	Analysis and Design of a Single-Phase Half-Bridge Rectifier/Inverter with an Active Resonant DC Bus Voltage balancer By Zoran MILETIC	[View] [Download]
Abstract: This paper presents the analysis and design of the single-phase half bridge rectifier with an active voltage DC bus balancer (ARVB). Impact of the power ripple on the DC bus of the ordinary rectifier/inverter and the rectifier/inverter with the ARVB is examined. It will be shown that with the ARVB, the volume and size of the DC bus; hence the converter can be significantly reduced, since the ARVB eliminates fundamental and the most significant component of the DC bus current.

	Frequency-Doubler Modulation for Reduced Junction Temperatures for LLC Resonant Converters Operated in Half-Bridge Configuration By Philipp REHLAENDER	[View] [Download]
Abstract: LLC resonant converters are typically unsuitable to be applied for wide voltage-transfer ratio applications. With a full-bridge inverter, however, they can be operated in a variety of different modulations. Most notably, by permanently turning on one MOSFET and turning off the other MOSFET of the same bridge leg, the LLC can be operated in half-bridge configuration reducing the gain by a factor of two. The resonant capacitor is hereby charged to an average voltage of half the input voltage. In this modulation, however, the switch that is permanently turned on is stressed by the complete resonant current while exhibiting no switching losses. This paper proves that the frequency-doubler modulation can better balance the losses among all MOSFETs and should be the preferred mode of operation favored over the conventional half-bridge modulation. This paper analyzes the beneficial loss distribution, proposes an on-the-fly morphing modulation and discusses potential operating strategies to further reduce the junction temperature. Furthermore, it is shown that this modulation can also be altered to achieve the asymmetrical LLC operation. Experimental measurement results show that the modulation results in a substantial decrease of the maximum MOSFET temperature and shows that the converter can be smoothly transitioned during operation from full-bridge modulation to the frequency-doubler half-bridge operation and back.

	Resonant Switched Capacitor DC-DC converter (RSCC) for Data Center applications By Haitao CHEN	[View] [Download]
Abstract: With rapid technological advancement and huge consumer requirements for cloud complex computing, Internet of things, big data storage and owing to various other increased consumer needs there comes more and more strain on the data centers. Furthermore, data centers too, have undergone through significant evolution in the recent years which has led their power losses to grow enormous and the CO2 emission as well has become significant. To provide a solution to an ever-growing stress on data centers and their huge power losses, in this paper a non-isolated, non-regulated, fixed voltage conversion ratio (4:1) step-down, DC-DC converter i.e. Resonant switched capacitor DC-DC converter (RSCC) for data center applications are proposed, presented and designed for achieving high efficiency and high-power density. Simulation validation and hardware design is done for the production of a hardware prototype. Moreover, the design methodology of resonant switched capacitor DC-DC converter prototype is presented.

	Superior usage of the Bidirectional Isolated Series-Resonant AC/DC Converter By Remco BONTEN	[View] [Download]
Abstract: Conventionally, grid-connected isolated AC/DC conversion is realized through a two-stage approach,resulting in an increased number of (magnetic) components and thus a cost-inefficient solution.Therefore, this paper focusses on an extension of a recently proposed control strategy, i.e.bidirectional charge control, for a bidirectional, isolated, series-resonant DC/DC converter. Bidirectionalcharge control targets a predefined charge displacement between two consecutive zerocrossingsof the resonant current and calculates the required switching levels for the semiconductorswitches accordingly. These switching levels are defined as a function of the charge differenceacross the resonant capacitor, realizing dynamic, bidirectional operation of the series-resonant converterwhile guaranteeing zero-voltage switching of all switches. In order to maintain grid quality,grid-tied converters are verified for compliance regarding their harmonic current emissions and totalharmonic distortion (THD). Therefore, power-factor correction (PFC) is a requirement for each ofthese converters. To achieve power-factor correction, a phase-locked loop is implemented with anouter control loop to realize sinusoidal grid-current waveforms and, as a result, low harmonic currentemissions that do comply to the standards and a low THD. The discussed control algorithm and thelinearization are verified through simulation for a 3kW electric vehicle battery charger to connect tothe single-phase grid. Nonetheless, wide primary, grid voltage and wide secondary, electric vehiclebattery voltage ranges have been shown applicable with bidirectional charge control. Although thesimulations show very promising results, realization on a prototype is recommended to validate thetheoretical analysis and prove the robustness of the proposed control strategy.