Interleaved resonant converter with the balanced flying capacitors

Abstract

This study presents a new DC/DC converter for high input voltage and high load current applications. To adopt low voltage rating power devices in high voltage applications, two split capacitors with four active switches are used in the primary side to reduce the voltage stress of power switches at V in /2. Two flying capacitances are used to automatically balance two split capacitor voltages in every switching cycle. The proposed converter includes two resonant circuits to share the load current and to reduce the current stress of passive components. If the switching frequency is less than the series resonant frequency, power switches can be turned on under zero-voltage switching and rectifier diodes can be turned off under zero current switching. Therefore the switching losses on power semiconductors are reduced. The interleaved pulse-width modulation is adopted to further reduce the ripple current at output side. Thus, the output filter inductances can be reduced. Finally, experiments with a 1.2 kW prototype are provided to verify the effectiveness of the proposed converter.

Discontinuous conduction/current mode analysis of dual interleaved buck and boost converters with interphase transformer

“…Whilst there is little published work on the optimum number of phases, most research is focused on two-phase systems. Other research has proposed a range of more complex topologies that, for example, provide larger step-up/down conversion ratios [12][13][14][15], soft-switching capability [4,12,13] and galvanic isolation [16,17]. However, the increased component count and increased peak voltage and current levels in these circuits tend to restrict them to low-power applications; furthermore, they are not always extendable to bi-directional power flow.…”

Analysis and implementation of a three‐level hybrid dc–dc converter with the balanced capacitor voltages

“…Multilevel converters based on the series-connected full-bridge circuits, flying capacitor topologies and clamped diodes have been proposed and researched to reduce the voltage stress of power switches for high-voltage applications such as medium power ac drivers [1,2], reactive power compensators [3,4], dc-based distributions or microgrids [5,6] and dc-based data storage or data centre [7,8]. Three-level zero-voltage switching (ZVS) converters [9][10][11][12][13][14] have presented to achieve low switching losses and high circuit efficiency. On the basis of the energy stored on the output inductors, the leading-leg switches of three-level converter can be turned on at ZVS within a wide load range.…”

Zero voltage transition–zero current transition pulse‐width modulated multiphase synchronous buck converter with an active auxiliary circuit for portable applications

“…In ZVT converters [26–29], generally the auxiliary switch actuates just before the main switch is made active and culminates after it is executed. The converters proposed [30–39] either provide ZVT or ZCT soft‐switching condition, making some switches in the converter to operate with hard switching that increases switching loss which affects the overall performance of the converter. Reducing the switching losses for a low‐voltage high‐current application with the assistance of a simple active auxiliary circuit is not present in the literature [1–39].…”