This paper presents research results of voltage gain number control methods of a power electronic resonant zero-current switching (ZCS) dc-dc switched-capacitor (SC) voltage multiplier (SCVM) in a topology with fault tolerance capability (FSCVM). The converters operated under the basic switching patterns are constant-voltage-gain dc-dc series-parallel resonant SC converters. However, this paper presents a method for the output voltage regulation by a special switching strategy. A variable voltage gain is made possible by selecting the number of active switching cells, using an appropriate control method. This creates a set of voltage ratio ranges. In addition, the proposed topology and method of control enable a fault-tolerant operation of the FSCVM under various failures of the device. The paper presents an analysis of the concept, simulation results and an experimental verification in a three-cell FSCVM dc-dc resonant boost converter operating at a 200 watt charge. Issues regarding the selection of components related to the problem of inrush currents which can occur during the voltage ratio increase are also analyzed in this paper, and the design for low inrush currents is demonstrated.

This paper presents the investigation results of the efficiency of power electronic resonant zero-current switching dc-dc switched-capacitor voltage multipliers (SCVMs) in three topologies. The analytical model of efficiency shows the impact of the converters' particular parameters on their properties and gives indications for an adequate design. The impact of the parameters of the semiconductor devices, parasitic resistances, switched capacitance value, number of switching cells, switching frequency, and choke design on the converters' efficiency is demonstrated. The converters are investigated analytically with the use of computer-based simulations and experimentally as a three-cell MOSFET-based SCVM dc-dc resonant boost converter. The in-depth analysis and the results obtained are some novel contributions to the existing knowledge of switched-capacitor-based power electronic conversion. Moreover, the presented method of analysis can be useful for analyzing other types of SC power converters comprising resonant switching circuits.

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.

This paper presents research results related to the concept of a high-voltage-gain DC-DC converter with a low input current ripple. In the proposed topology, a low-volume DC-DC switch-mode boost converter operates in parallel with a switched-capacitor voltage multiplier (SCVM). The overall converter achieves a four-fold voltage gain, but the voltage stress of the transistor and the diode of the boost converter is only half of the output voltage. This is achieved by applying the specific topology of the proposed converter. Furthermore, the boost part uses a low-volume choke as it operates in the discontinuous conduction mode (DCM). The parallel operation of the boost converter with the SCVM decreases the current stress in some components of the multiplier. This paper presents a concept of the hybrid converter, an analytical model for the selection of components and switching parameters, an efficiency model, and the verification of the converter operation through simulation tests and experiments.

This paper presents a concept for the operation of a resonant DC–DC switched-capacitor converter with very high efficiency and output voltage regulation. In its basic concept, such a converter operates as a switched-capacitor voltage doubler (SCVD) in the Zero Current Switching (ZCS) mode with a constant output voltage. The proposed methods of switching allow for the switched-capacitor (SC) converter output voltage regulation, and improve its efficiency by the operation with Zero Voltage Switching (ZVS). In this paper, various switching patterns are proposed to achieve high efficiency and the output voltage control by frequency or duty cycle regulation. Some examples of the application of the proposed switching patterns are presented: in current control at the start-up of the converter, in a bi-directional converter, and in a modular cascaded system. The paper also presents an analytical model as well as the relationships between the switching frequency, voltage ratio and efficiency. Further, it demonstrates the experimental verification of the waveforms, voltage ratios, as well as efficiency. The proposed experimental setup achieved a maximum efficiency of 99.228%. The implementation of the proposed switching patterns with the ZVS operation along with the GaN-based (Gallium Nitride) design, with a planar choke, leads to a high-efficiency and low-volume solution for the SCVD converter and is competitive with the switch-mode step-up converters.