Nosov Magnitogorsk State Technical University, Magnitogorsk, Russia:
A. A. Nikolaev, Cand. Eng., Associate Prof., Head of the Dept. of Automated Electric Drive and Mechatronics, e-mail: aa.nikolaev@magtu.ru
R. R. Dyoma, Dr. Eng., Prof., Dept. of Machines and Technologies for Metal Forming and Mechanical Engineering, e-mail: demarr@magtu.ru
P. G. Tulupov, Cand. Eng., Associate Prof., Dept. of Automated Electric Drive and Mechatronics, e-mail: tulupov.pg@mail.ru
S. S. Ryzhevol, Post-graduate Student, Dept. of Automated Electric Drive and Mechatronics, e-mail: snaffls18@gmail.com

The structure of the circuit for indirect control of the total conductivity in the electric mode control system of HIREG EAFs (Danieli, Italy) is considered. For furnaces on which this system is installed, the problem of overestimated standard deviations of currents and powers of electric arcs is indicated, which leads to non-optimal operation and increased operating costs. As a solution, it is proposed to use the concept of a digital twin to adapt the control loop settings to the current conditions of charge melting. The main idea of the proposed solution is to use a digital analogue of the electrical circuit of the furnace with the HIREG control system to carry out an iterative search for the most optimal controller parameters, provided that its non-optimal operation is detected in accordance with a set of predetermined criteria. The results of the study were implemented on the basis of one of the domestic furnaces. A technical effect has been achieved in the form of a reduction in the standard deviations of the signals of currents and powers of electric arcs, which has ensured a reduction in time under current and the specific consumption of electricity.
This work was supported financially by the Ministry of Science and Higher Education of the Russian Federation (Project No. FZRU-2023-0008).

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