Nosov Magnitogorsk State Technical University, Magnitogorsk, Russia:

A. A. Nikolaev, Cand. Eng., Head of the Dept. of Automated Electric Drive and Mechatronics, e-mail: aa.nikolaev@magtu.ru
G. P. Kornilov, Dr. Eng., Head of the Dept. of Power Supply of Industrial Enterprises, e-mail: korn_mgn@mail.ru
P. G. Tulupov, Junior Researcher, Dept. of Power Supply of Industrial Enterprises, e-mail: tulupov.pg@mail.ru
S. S. Ryzhevol, Postgraduate Student, Dept. of Automated Electric Drive and Mechatronics, e-mail: snaffls18@gmail.com

As part of the work, new methods for controlling the electric mode of steel-arc furnaces (EAF) and ladle-furnace units (LF) are considered in detail using diagnostics of the melting stage by higher harmonics of arc currents and voltages. The features of the application of these methods on furnaces of various capacities and classes are analyzed, taking into account the experience of practical research at steel plants in Russia and abroad. As a result of the work, detailed recommendations were formed on the rational use of various methods for diagnosing the melting stage, depending on the type of furnace installation and the method of charge loading. Adequate use of systems for diagnosing the stage of charge melting by higher harmonics of arc currents and voltages makes it possible to increase the energy efficiency of the furnace plant by reducing the specific power consumption. This fact substantiates the effectiveness of approaches proposed in the study. The results of this work can be useful to researchers in the field of energy-efficient control of furnace units, manufacturers of EAF and LF electric mode control systems, as well as direct manufacturers of liquid steel in the modernization of existing enterprises.
This work was supported financially by the Ministry of Science and Higher Education of the Russian Federation (Project No. FZRU-2020-0011).

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