Analysis of the number of switches of on-load tap changer of a power transformer for field substation, taking into account discrete time and voltage level samplingT.V. Tabachnikova, L.V. Shvetskova and A.V. YumalinE3S Web Conf., 220 (2020) 01056DOI: https://doi.org/10.1051/e3sconf/202022001056