Abstract
With the development of power electronics technology, modular multilevel converter (MMC) has become a popular converter due to its high modularity and good output characteristics. In recent years, half-bridge MMC has been widely studied. Compared with half-bridge MMC, MMC using full bridge sub-modules is more competitive because of its excellent DC short-circuit fault ride-through capability. Furthermore, the balance of capacitor voltages of sub-modules has a crucial influence on the working performance of MMC. To figure out the influence of non-ideal factors on the balance of capacitor voltages, this paper analyses the difference of the capacitor voltages and compares the unbalanced degree of capacitor voltages under different conditions. Firstly, in an ideal situation, the analytical expressions of bridge arm current and capacitor voltage increments are obtained, revealing the dynamic balance process of capacitor voltages. Secondly, expressions in a non-ideal condition reveal the effect of on-resistances of switching devices on the capacitor voltages. Finally, the influence of loss distributions in sub-modules on the balance of the capacitor voltages is analysed theoretically. Simulation models are built in PLECS to verify the theoretical analysis.
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 callMore From: IOP Conference Series: Earth and Environmental Science
Disclaimer: 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.
