2025

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Browsing 2025 by Author "Kuznetsov, Vitalii V."

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    Adaptation of a Predicate Model in Control Problems of Nonstationary Static Objects
    (Український державний університет науки і технологій, ННІ «Дніпровський металургійний інститут», ІВК ≪Системні технології≫, Дніпро, 2025) Tryputen, Mykola; Kuznetsov, Vitalii V.; Verovkin, Oleksandr; Ivliev, Vitalii
    ENG: When controlling static objects at the optimization level, pattern recognition methods are used that allow partitioning the factor space into elementary subdomains in the form of n-dimensional hyperparallelepipeds. One of the main elements of the control structure for this approach to control is the adaptation algorithm, that makes it possible to refine the description of a static object under nonstationarity conditions. Repeated use of the adaptation algorithm to refine the model leads to an unjustified complication of its logical structure and the accumulation of information that has lost its relevance. The paper proposes a method for minimizing the description of images of technological situations, that makes it possible to overcome the indicated disadvantages. The method is based on the property of invariance of the number of parameters defining the hyperparallelepiped to the size of the described area in the factor space. This made it possible to identify significant boundary sub-areas in the description of the image of technological situations and, by their subsequent combination in the direction of the feature axes, to select a description with a minimum number of sub-areas. When performing these operations, “outdated” information is removed and the logical structure of a static control object is simplified as much as possible. The paper shows the possibility of implementing an algorithm for minimizing the description of images on the basis of α-algebra, that makes it possible to integrate its control structures using relational data models. The effectiveness of the proposed algorithm is confirmed by computational experiments in the control of the process of lump crushing for the conditions of a mining and processing plant.
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    Increasing the Reliability of Simulation of Asynchronous Motor Operation Based on an Adaptive Approach
    (Український державний університет науки і технологій, ННІ «Дніпровський металургійний інститут», ІВК ≪Системні технології≫, Дніпро, 2025) Tryputen, Mykola; Kuznetsov, Vitalii V.; Verovkin, Oleksandr; Koliadenko, Oleksandr
    ENG: This research focuses on improving the reliability of simulating the operation of induction motors when solving technical and economic problems related to the selection of protection systems for electric drives operating in industrial power networks with poor power quality. The presence of voltage asymmetry, harmonic distortions, and other power quality issues in workshop networks significantly affects the performance and service life of induction motors, increasing energy losses and maintenance costs. The article proposes a power and economic model that allows conducting computational experiments to determine the optimal solution for improving power supply quality. A key element of the model is the system for generating and controlling linear voltage parameters, which ensures compliance of the simulated signals with their statistical regularities observed in real industrial conditions. The research introduces adaptive algorithms for the continuous and simultaneous assessment of average values, variances, autocorrelation, and cross-correlation functions of voltage harmonics. Mathematical expressions for their correction during the accumulation of information are presented. Structural schemes of control systems for both analog and digital modeling of voltage processes are proposed, allowing for real-time monitoring of the reliability of generated data. The simulation results were verified through statistical hypothesis testing for the average values and variances of the generated voltage harmonics. Experimental studies were carried out in the rolling shop No. 1 of Dneprospetsstal LLC, where significant voltage distortions are caused by the operation of powerful semiconductor converters. The results confirmed the adequacy of the proposed modeling approach and its applicability for making economically sound decisions regarding the choice of technical solutions for voltage quality improvement. This work contributes to the field of energy efficiency in industrial enterprises by providing a methodological basis for the reliable simulation of induction motor operation in the presence of distorted power supply conditions. The proposed approach allows reducing the cost and duration of experimental studies by replacing them with validated computational modeling.