Choosing variable-frequency drive systems for the mining process unitsNatalia Kugusheva, Alexander Semenov, Ilya Yakushev, Svetlana Pavlova, Ayaal Egorov and Oleg FedorovE3S Web Conf., 244 (2021) 09011DOI: https://doi.org/10.1051/e3sconf/202124409011