Abstract
This paper proposes a novel dc-dc converter topology to achieve an ultrahigh step-up ratio while maintaining a high conversion efficiency. It adopts a three degree of freedom approach in the circuit design. It also demonstrates the flexibility of the proposed converter to combine with the features of modularity, electrical isolation, soft-switching, low voltage stress on switching devices, and is thus considered to be an improved topology over traditional dc-dc converters. New control strategies including the two-section output voltage control and cell idle control are also developed to improve the converter performance. With the cell idle control, the secondary winding inductance of the idle module is bypassed to decrease its power loss. A 400-W dc-dc converter is prototyped and tested to verify the proposed techniques, in addition to a simulation study. The step-up conversion ratio can reach 1:14 with a peak efficiency of 94% and the proposed techniques can be applied to a wide range of high voltage and high power distributed generation and dc power transmission.
Highlights
D ISTRIBUTED generation is playing an increasingly important role in reducing greenhouse gas emissions and improving the quality of human lives
This paper proposes a novel ultrahigh step-up dc–dc converter, which utilizes the features of modularity, multilevels and electrical isolation
With the shielding control strategy [see Fig. 14(c)], the energy can be transferred to the secondary side without incurring a voltage drop across the idle windings and the input current increases dramatically
Summary
D ISTRIBUTED generation is playing an increasingly important role in reducing greenhouse gas emissions and improving the quality of human lives. Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org In these applications, high voltage gain and high conversion efficiency of dc–dc converters are highly desirable. In order to increase the power level, a modular multilevel converter is presented in [45] but it can only regulate the duty ratio and cell number (i.e., 2DoF) These reported topologies do not provide electrical isolation and sufficient flexibility for further expansion. This paper proposes a novel ultrahigh step-up dc–dc converter, which utilizes the features of modularity, multilevels and electrical isolation. In effect, this is a three degree of freedom (3DoF) design of dc–dc converters
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
