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<span>This paper presents a hybrid pulse width modulation (HPWM) strategy based on different switching patterns of selective harmonic elimination pulse width modulation (SHEPWM) for the three-level neutral point clamped (3L-NPC) converter. Specific low-order harmonics can be eliminated by SHEPWM at low switching frequency, while the remaining high-order harmonics can be selected to be simply filtered by additional hardware. Large oscillation waveform usually occurs in the transition instant between two diverse modulation situations, therefore switching between distinct switching patterns can be problematic if no effective means is taken, especially when the effect of smooth and fast transition at any time is considerable. A universal and valid control strategy, which maintains the high-quality output voltage and current, is proposed and implemented in this paper to address this issue. Simulation results obtained from MATLAB/SIMULINK are presented to analyze the performance and validate the feasibility and effectiveness of this control scheme.</span>

This article considers the development of digital twins (DT) for the mechatronic facilities of the coiling machine group in a wide-strip hot rolling mill. The analysis of Russian and foreign sources confirmed that a lot of attention is paid to the economy digitalization. All of the leading metal plant equipment and electrical engineering system manufacturers are working on creating DTs. The analysis of the literature showed that the authors lack a uniform understanding of the conceptual directions in the creation of DTs and there are many definitions of this term. Therefore, the first part of the article deals with the analysis of the digital twin concepts according to their application at industrial companies. The authors substantiate the feasibility of the DT de-velopment for the electromechanical and mechatronic systems of the most complex metal production components, i.e., rolling mills. This initiative development is relevant due to the reconstruction of the 2500 wide-strip hot rolling mill at Magnitogorsk Iron and Steel Works PJSC (MMK PJSC) that involves the installation of unique equipment. Due to this, the development of DTs to implement the virtual commissioning of the equipment becomes a priority. The virtual adjustment of automation and process control systems is also required. This problem can be solved through the example of three coiling machines, each of which has electric and hydraulic auxiliary equipment. These coiling machines are used for rolling the heavy hot-rolled bar and they feature a unique design. Therefore, the development of DTs for mechatronic facilities is a novel scientific problem. The authors propose the methods for the development of DTs used in the virtual commissioning of process control systems. They present the structure of the coiling section automation system and the structure of the DT imple-mented on the basis of programmable logic controllers (PLC). The authors provide the specifications for the Siemens PLCs installed at each of the coiling machines and the coiling machine master controller. To develop the control systems for electric and hydraulic drives, it is recommended to use the Matlab Simulink software package. The authors provide temporal dependencies obtained using DTs and other similar oscillograph charts produced during the operation of the coiling machine that can help model the operation of the mechanisms in question. The results of their comparison show that the processes correspond to each other. Thus, the use of the developed DT to adjust the electrotechnical systems of rolling mills is reasoned. The accepted concept of making digital twins for the electrotechnical systems of rolling mill components is relevant and technically feasible

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