Кафедри

Постійне посилання на розділhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/35393

Переглянути

Результати пошуку

Зараз показуємо 1 - 6 з 6
  • Ескіз
    Документ
    Synthesis of the algorithm for the flow parameters optimal control of the reversible conveyor
    (Національний університет "Запорізька політехніка", 2022) Pihnastyi, O. M.; Ivanovska, O. V.; Sobol, Maksym
    The problem of optimal control of flow parameters of a conveyor-type transport system containing sections with reversible conveyors is considered. The object of the stady was an analytical model of a reversible transport conveyor for synthesizing an algorithm for optimal control of the flow parameters of a reversible transport conveyor. The goal of the work is to develop a synthesis technique for an algorithm for optimal control of the flow parameters of a reversible transport conveyor based on an analytical model of a conveyor section containing a transport delay. An analytical model of a reversible conveyor has been developed for the case of a constant speed of a conveyor belt, which makes it possible to determine the values of the output flows from the reverse section with known values of material flows coming to the input of the conveyor section. To build a model of the reversible section of the conveyor, an analytical model of the section of the conveyor in partial derivatives, containing the transport delay, was used. When constructing the model, the assumption was made about the instantaneous switching of the direction of movement of the conveyor belt, and it is also assumed that the interval between switching the direction of the belt speed exceeds the values of the transport delay for the conveyor section. To synthesize an algorithm for optimal control of the reversible conveyor, a control quality criterion was introduced. The formulation of the problem of optimal control of the flow parameters of the reversible conveyor is given, based on the Pontryagin maximum principle. The Hamilton function for the controlled system is written, taking into account the criterion of the quality of control of the reversible conveyor. A technique for synthesizing an algorithm for optimal control of the material output flow of a section of a reversible conveyor is demonstrated. The conditions for switching the direction of the speed of the conveyor belt are determined. The developed model of the reversible conveyor section is used to synthesize an algorithm for optimal control of the material output flow of the reversible conveyor section. A method for the synthesis of algorithms for optimal control of the flow parameters of a transport system with sections containing reversible conveyors has been developed. The construction of an analytical model opens up new perspectives for the design of transport conveyor control algorithms, which can be used to reduce the specific energy costs for material transportation in the mining industry.
  • Ескіз
    Документ
    Predicting the parameters of the output flow of conveyor systems
    (Institute of Electrical and Electronics Engineers, Inc., USA, 2021) Pihnastyi, O. M.; Kozhevnikov, G. K.; Ivanovska, O. V.
    In this article, the problem of constructing models of multi-section conveyor-type transport systems using a neural network is considered. The analysis of models of long-distance multi-section transport systems, which are used to design control systems of the flow parameters from the point of view of reducing the unit costs of material transportation, is presented. The areas of the models' application and associated limitations are demonstrated. The advantages of using neural networks for developing multi-section transport systems models are shown. The influence of the initial distribution of materials along the transport route and the presence of a transport delay in the system on the quality of prediction of the transport system flow parameters are estimated. The effect of the use of speed sensors located on the inner and output sections in order to improve the quality of prediction of the transport system flow parameters is analyzed. It is shown that the use of speed sensors in conveyors with belt speed control can significantly improve the quality of predict.
  • Ескіз
    Документ
    Improving the Prediction Quality for a Multi-Section Transport Conveyor Model Based on a Neural Network
    (2022) Pihnastyi, O. M.; Ivanovska, O. V.
    The multi-section transport conveyor model based on the neural network for predicting the output flow parameters is considered. The expediency of using sequential and batch modes of training of a neural network in a model of a multi-section transport conveyor has been investigated. The quality сriterion of predicting the output flow parameters of the transport system is written. Comparative analysis of sequential and batch modes of neural network training is carried out. The convergence of the neural network training process for different sizes of the training batch is studied. The effect of the batch size on the convergence rate of the neural network learning process is estimated. The results of predicting the output flow parameters of a multi-section transport system for models based on a neural network that was learned using training batches of different sizes are presented. A nonlinear relationship between the batch size and the convergence rate of the neural network learning process is demonstrated. The recommendations are given on the choice of learning modes for a neural network in the model of a multi-section transport conveyor. The choice of the initialization value of the node participating in the formation of the bias value is investigated. The qualitative regularities characterizing the influence of the choice of the node initialization value on the forecasting accuracy of the output flow parameters of the transport system are studied.
  • Ескіз
    Документ
    Maxwell-Element Model for Describing Conveyor Belt Stresses
    (2021) Pihnastyi, O. M.; Kozhevnikov, G. K.; Ivanovska, O. V.
    The wave equation which allows researching the occurrence and the dynamic stress propagation in the conveyor belt is obtained for the conveyor belt, the material of which corresponds to the Maxwell element model. The boundary and initial conditions were written for power switching modes to consider the mechanical characteristics of the asynchronous engine with the phase rotor, which determine the dependencies between the traction torque and the rotational speed of an asynchronous electric engine with a phase rotor. The estimate is given to separate wave equation terms. The expression is obtained for the calculation propagation belt speed of the dynamic stress along the conveyor belt. The conditions are shown by which the wave equation will correspond to the model of Hooke’s element. By designing the dependencies between the traction torque and the rotational speed for a specified interval of the mechanical characteristic, linear approximation is used. It is shown that the change of the material flow value coming into a section input doesn’t render a special influence on the dynamic stresses' propagation process along the conveyor belt. The expressions are obtained for dynamic stress propagation speed calculation. By deriving the wave equation, it is assumed the uneven material distribution along the conveyor section
  • Ескіз
    Документ
    Using a two-level dynamic PDE model to synchronize the performance of technological equipment of a production line
    (Національний університет "Одеська морська академія", 2021) Pihnastyi, O. M.; Ivanovska, O. V.
    The problem of designing a system for optimal operational control of random deviations in the productivity of technological equipment is considered. To construct an algorithm for optimal control of the performance of technological equipment, a PDE-model of a production flow line was used. The Lyapunov functions method was used to determine the value of the optimal control of the technological equipment performance. The production line is considered by a distributed dynamic system. Equations are written for the flow parameters of the production line in small perturbations. A criterion for the quality control of the performance of technological equipment of a production flow line has been introduced. Based on this criterion, the Lyapunov function is determined for the considered production system. Taking into account the form of the Lyapunov function, control actions are obtained that correct the performance of the technological equipment. The introduced control made it possible to ensure the synchronization of the productivity of the technological equipment of the production line and the asymptotic stability of the given planned state of the flow parameters of the production line for the steady and transient operation mode.
  • Ескіз
    Документ
    The problem of stabilizing the productivity of the technological equipment of the production line
    (2021) Pihnastyi, O. M.; Ivanovska, O. V.
    The problem of designing a system for optimal operational control of random deviations in the productivity of technological equipment is considered. The synthesized control ensures the synchronization of the productivity of the technological equipment of the production line and asymptotic stability of the given planned state of the flow parameters of the production line for the steady and transient mode of operation.