Meng, Yongqing; Shang, Shuonan; Zhang, Haitao; Cui, Yong; Wang, Xifan: 'IDA-PB control with integral action of Y-connected modular multilevel converter for fractional frequency transmission application', IET Generation, Transmission & Distribution, 2018, 12, (14), p. 3385-3397, DOI: 10.1049/iet-gtd.2017.0573
IET Digital Library, https://digital-library.theiet.org/;jsessionid=6sat4ilpd83t7.x-iet-live-01content/journals/10.1049/iet-gtd.2017.0573