Browsing by Author "Sivyakova, Galina"

Now showing 1 - 2 of 2

Assessment of Human-Operator’s Influence on Technical and Economic Indicators of the Excavator Production Cycle
(Dnipro University of Technology, Dnipro, 2025) Tytiuk, Valerii; Mrachkovskyi, D.; Chornyi, Oleksii; Kuznetsov, Vitalii V.; Tryputen, Mykola; Sivyakova, Galina
ENG: Purpose. Determining the influence of the parameters of the human-operator transfer function on the duration of the technological operation and the cyclic energy consumption of the electromechanical system of a straight shovel excavator equipped with electric drives of various types in order to further improve the human-machine control system of open-pit excavators by compensating for the inertia and nonlinearity of the human-operator characteristics. Methodology. Mathematical modeling of the human-machine control system of an excavator equipped with electric drives of various types, taking into account the dynamic characteristics of the human-operator, establishing regression dependencies of technical and economic indicators of the excavator on the parameters of the equivalent transfer function of the human-operator using design of experiments. Findings. The mathematical models of closed-loop control systems for the position of the bucket of a “straight shovel” excavator with an electric drive according to the Leonard system and a thyristor converter-motor electric drive have been implemented, which differ in that their structure takes into account the nonlinearity and inertia of the human operator and its influence on the performance of the human-machine system. Using the methods of the theory of experiment planning, we obtained regression dependences of the duration of the technological cycle and cycle energy consumption on the values of the time constant and the delay constant, which characterize the current state of the human-operator. The obtained regression models made it possible to evaluate the importance of the influence of various psycho-physiological factors of the human-operator on the technical and economic indicators of the excavator production cycle, which can serve as the basis for further optimization of the operation of mining excavators. Originality. For the first time, mathematical models of the electromechanical system of an excavator according to the “straight shovel” scheme are proposed, including models of electric drives of the main mechanisms, a model of the mechanical part of the excavator and a model of a human-operator, which made it possible to increase the accuracy of determining the energy consumption of the excavator and the time of the operating cycle. The regression models of technical and economic indicators of the excavator production cycle on the delay and inertia of the human-operator were obtained. It was found that the more influential factor is the transportation delay. Practical value. Mathematical models of an excavator with an electric drive based on the generator-motor system and an electric drive based on the thyristor converter-motor-motor system have been developed, including a model of the mechanical part of the excavator and a model of a human-operator. Regression models of the dependence of the duration of the excavator production cycle and its energy consumption on the delay and inertia of the human-operator are obtained. The proposed implementation of the human-machine excavator control system creates prerequisites for further increasing the level of automation of mining excavators.
Preventing the Development of Emergency Modes of Interlocked Electric Drives of a Rolling Mill under the Impact Loads
(Polish Society of Technical Diagnostics (Polskie Towarzystwo Diagnostyki Technicznej - PTDT), 2023) Druzhinin, Valeriy; Sivyakova, Galina; Kalinin, Alexey; Tytiuk, Valerii; Nikolenko, Anatolii V.; Kuznetsov, Vitaliy V.; Kuzmenko, Mykhailo
ENG: In recent years, due to the tightening of competition in the global market of steel producers, the requirements for the quality of hot-rolled steel have increased. The finishing group of the rolling mill is characterized by a complex structure of mechanical and electrical parts. The operation of electric drive systems of such units is characterized by the interrelation of electromagnetic processes, mechanical phenomena and technological factors. As experimental studies have shown, the quality of the supply voltage is inextricably linked with the impact nature of the loads in the rolling stands of the roughing and finishing groups of the hot rolling mill. A decrease in the supply voltage may be accompanied by the development of emergency modes of synchronous electric drives, leading to a decrease in the quality of the finished product.The paper developed a mathematical model of the power supply system of the rolling mill JSC "ArcelorMittal Temirtau". It is shown that this can lead to loss of synchronism of the synchronous motor. Such a voltage drop has a significant impact on the operation of DC electric drives of the finishing group. Various strategies are proposed to counter the development of emergency situations.