AUTHOR=Ma Junchao , Wu Zhe , Sun Ke , Wang Chenxu , Lu Chengyu , Gu Yilei , Liu Jianing , Zhu Chengzhi , Guo Hanlin , Zhang Zheren , Xu Zheng TITLE=Research on variable pairing scheme for V/f controlled MMC station JOURNAL=Frontiers in Energy Research VOLUME=12 YEAR=2024 URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2024.1400285 DOI=10.3389/fenrg.2024.1400285 ISSN=2296-598X ABSTRACT=

Grid-forming control is a promising solution for renewable power integration. This work presents a variable pairing scheme for the voltage controller of V/f controlled modular multilevel converter in an islanded network with a synchronous machine, which is a special type of grid-forming control. Based on the concept of the relative gain array (RGA), it is found that the RGA can be derived using steady-state sensitivity analysis. Then, the steady-state characteristics of the typical electrical components in the islanded network are considered, and the analytical expression for calculating the RGA is derived. Based on a typical system, a variable pairing scheme is then suggested using the calculated RGA elements. The time-domain simulations are conducted using PSCAD/EMTDC, and the results verify the feasibility and advantages of the suggested variable pairing scheme.