Abstract
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 and 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.
Highlights
DC-DC conversion based on switched-capacitor (SC) circuits allows a high-voltage-gain converter [1] to be achieved that can be optimized for low volume or high efficiency
- The input current ripple is reduced significantly; - The application of the switch-mode part connected in parallel to the SC converter reduces the current burden of the SC converter, and the total cost of the converter may not rise when the hybrid concept is introduced; - The efficiency of the hybrid converter is higher than that of the classical switched-capacitor voltage multiplier (SCVM) for higher values of power; the proposed converter might be a better solution for use in higher power applications; - The switch-mode converter, built in the boost topology, operates in the deep discontinuous conduction mode (DCM) mode with a low duty cycle
Its choke has a small inductance and volume; - The boost converter operates with a low output voltage, which allows the use of high-quality semiconductor switches of low cost; - Very favorable design relationships show that the inductance of the boost converter should be decreased as the power of the converter increases
Summary
DC-DC conversion based on switched-capacitor (SC) circuits allows a high-voltage-gain converter [1] to be achieved that can be optimized for low volume or high efficiency. The converters proposed in [14]–[17] are built as a hybrid switched-capacitor/switched-inductor (SC/SI) structure with inductors on the input side This allows for a decrease in the input current ripple by the utilization of the proposed topology and control concept, as well as the use of the SC structure for adequate voltage gain achievement. The high-gain converter with improved efficiency presented in [20] uses distributed stray inductances and operates in an interleaved SC structure with a common input and output capacitor, resulting in a reduction in current ripple. Together with the previously published conference paper [34], this work introduces a novel topology of the high-gain DC-DC step-up converter with reduced input current ripple achieved by a parallel operation of an SCVM converter and a switch-inductor circuit equipped with a low-volume inductor. All results obtained here lead to the positive conclusions described in the last section of this paper
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
