Farid Mohammadi, Gevork B. Gharehpetian, Hasan Rastegar, et al. Non-isolated Step-up DC-DC Converter Based on Switched Capacitor Cells[J]. CSEE Journal of Power and Energy Systems, 2023, 9(3): 1161-1172.
DOI:
Farid Mohammadi, Gevork B. Gharehpetian, Hasan Rastegar, et al. Non-isolated Step-up DC-DC Converter Based on Switched Capacitor Cells[J]. CSEE Journal of Power and Energy Systems, 2023, 9(3): 1161-1172.DOI: 10.17775/CSEEJPES.2021.07370.
Non-isolated Step-up DC-DC Converter Based on Switched Capacitor Cells
摘要
Abstract
A non-isolated high gain step-up DC-DC converter for low power applications is suggested in this study. In the designed transformerless converter
the main switch current and voltage stress is reduced while maintaining high voltage gain. For instance
with a duty cycle of 0.5 a voltage gain equal to 5 is achieved while the normalized switch voltage stress is 0.4. Also
it decreases power losses of active and passive elements. In the proposed converter design
the switched-capacitor (SC) technique is used to obtain maximum voltage transfer gain using only one switch. The three modes of operation
i.e.
continuous conduction mode (CCM)
boundary conduction mode (BCM)
and discontinuous conduction mode (DCM)
are studied in detail. The small signal analysis (SSA) of the designed converter is investigated
and its steady-state model is examined under CCM. Performance of the proposed converter proposed in this study is assessed and tested using a prototype. Efficiency of the converter is recorded above 94% in a wide range of output powers. Overall
compared to the other converters
the results suggest satisfactory performance of the designed converter. An issue of the proposed converter is that its input current is not smooth due to using the switched-capacitor cell in its structure. This issue is alleviated by using input filters.