Dynamic methods of identification of electromagnetic parameters of power transformers in non-stationary modeM.G. Popov, Yu.N. Bocharov, E.I. Gurevich, F.H. Halilov and V.V. PopovE3S Web Conf., 91 (2019) 01002DOI: https://doi.org/10.1051/e3sconf/20199101002