Blahnik, Vojtech, Tomas Kosan, Zdenek Peroutka, and Jakub Talla. “Control of AC/DC Modular Multilevel Converter”. Elektronika ir Elektrotechnika 24, no. 6 (December 17, 2018): 11-14. Accessed October 22, 2020. https://eejournal.ktu.lt/index.php/elt/article/view/22282.