Application of an auto-parametric circuit for controlling thyristor converters E G Usmonov, D S Akhmetbaev, M Mamutov, Sh Abdurakhmonov and M. Turgunov E3S Web Conf., 289 (2021) 07015 Published online: 13 July 2021 DOI: 10.1051/e3sconf/202128907015