High-Gain Switched-Capacitor DC-DC Converter With Low Count of Switches and Low Voltage Stress of Switches

Robert Stala,Stanislaw Pirog,Andrzej Mondzik,Zbigniew Waradzyn,Maciej Chojowski,Adam Penczek,Szymon Folmer,Aleksander Skala

doi:10.1109/access.2021.3104399

Robert Stala, Stanislaw Pirog + Show 6 more

Open Access

https://doi.org/10.1109/access.2021.3104399

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Abstract

This paper presents a novel concept of a high-voltage-gain DC-DC converter. The converter is made up of switched capacitors and passive resonant branches. A significant reduction in the count of switches and low voltage stress on the switches is achieved in this proposed converter topology, in comparison to that of a classical SC series-parallel converter. It is essential from the cost, volume, and efficiency of the converter standpoint. The reduction in the count of switches is threefold. The highest voltage stress on the switches depends on the output voltage and is decreased in the proposed converter as well, as the output voltage is divided into two series-connected capacitors. The presented results demonstrate the operation of the converter with the use of resonant branches, its switching strategies, voltage stresses of switches, efficiency, voltage gain, and output voltage regulation as well as the zero-voltage switching (ZVS) operation. The paper also presents novel issues related to analytical loss modeling, extended concepts of topology, converter start-up, and operation during transient states. The demonstrated concept of the converter, the analytical discussion and its design, as well as the experimental setup and results clearly demonstrate the optimization achievements.

Highlights

SWITCH-CAPACITOR (SC) circuits can be used in one of the methods for DC energy conversion [1], [2]
The topology proposed in this paper allows for a reduction of Coss loss by the zero-voltage switching (ZVS) operation and the limitation of the number of switches despite a relatively high voltage gain
This paper presents a novel concept of the topology and switching methods of a novel DC-DC converter

Summary

INTRODUCTION

SWITCH-CAPACITOR (SC) circuits can be used in one of the methods for DC energy conversion [1], [2]. The concept proposed in [9] has been improved to the symmetric structure composed of two switched-capacitor cells, which is presented in [10] It allowed the ZVS operation and output voltage regulation [10]. The ZVS operation is presented for the Dickson resonant SC converter in [23] and in [27]–[28] for families of resonant SC converters In some concepts, such as [17] and [18], the converter uses switched capacitors and inductors to achieve high voltage gain, decrease in the number of switches, and output voltage regulation by duty cycle control. The topology proposed in this paper allows for a reduction of Coss loss by the ZVS operation and the limitation of the number of switches despite a relatively high voltage gain.

CONCEPT OF THE NOVEL CONVERTER

START-UP AND TRANSIENT RESPONSE OF THE SCVM

EXPERIMENTAL RESULTS

CONCLUSION