Vol 28, No 3 (2020)

Informatics, Computer Science and Control

Development of hierarchical functional models for diag-nostics of asynchronous electric motors using IDEF0 methodol-ogies

Vereshchagina .S.


The paper proposes an approach to diagnostics of asynchronous electric motors based on the application of hierarchical functional models that are built using the IDEF0 methodology for integrated consideration of the influence of electric power quality indicators. A brief analysis of the problems of diagnostics for asynchronous electric motors is given, which justifies the relevance of developing new methods and models of diagnostics. A distinctive feature of the proposed hierarchical functional diagnostic models of asynchronous electric motors is a formalized representation of the necessary process functions using the IDEF0 methodology. This allows one to identify the main data flows in the diagnosis process, extract knowledge about the process, and reveal the cause-and-effect relationships of failures of asynchronous electric motors, complementing traditional methods of technical diagnostics by analyzing compliance with regulatory requirements concerning the electrical energy quality. A brief description of the developed methods, models and algorithms, as well as the results of experimental research, efficiency analysis of the proposed methodology is provided.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):6-23
pages 6-23 views

Methodology for distributing information protection tasks between computer devices of automated systems based on the branch and border method

Gnutov M.S., Sizonenko A.B.


The influence of software protection on various information systems is analyzed. Using set theory, the use of computational resources for the joint solution of direct tasks and information protection tasks in an automated system is described. A hybrid implementation of computing in a CPU + GPU system is proposed. The relevance of using the branch and bound method to compile a minimum schedule of information security tasks in a hybrid multiprocessor system is considered. The features of processing data structures by various types of calculators are indicated. The computational strategies of the branch and bound method with the greatest possibility of acceleration with limited resources are analyzed. The efficiency criterion is selected, the performance indicators are considered when applying the frontal and one-sided branching strategies depending on the complexity of the calculations and the amount of occupied memory. The generalized indicator of efficiency is defined. The prospects of applying the considered method in distributed systems through distributed programming are emphasized.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):24-34
pages 24-34 views

Cognitive aggregate-flow metamodel of the process automatic spacecraft flight control

Kovtun V.S.


Currently, there is an urgent scientific problem of ensuring the effective implementation of the automatic spacecraft (AS) flight program, taking into account the material, energy and information resource limitations of onboard systems (OS). The consumption of OS resources largely depends on the synergistic phenomena that occur during intersystem interaction in the AS. By using these phenomena, it is possible to increase the efficiency of the use of existing resources, as well as to supplement them with new "synergistic" resources [1,2]. At the same time, synergistic phenomena can lead to premature development of the OS resource and unforeseen (non-calculated) failures and accidents [3]. For purposeful search and use of these synergistic phenomena, it is necessary to conduct a special study of the processes occurring on board. Research becomes possible only when moving from the system-cybernetic model of AS as a " black box "to a system-cybernetic model that provides" transparency "of AS as a" white box", which requires high accuracy and complexity of analysis of processes occurring on board [4]. This situation determines the urgency of developing new engineering techniques and modeling technologies. To create them, it is necessary to solve the problem of the initial stage of building models that describe in one form or another the engineering knowledge of OS development experts and flight control specialists [5]. The development of a universal method for solving the problem of the initial stage of modeling is significantly complicated due to the wide variety of OS, each of which has its own emergent and synergistic properties, which largely depend on the "non-clonability" of their elements [6,7].

In order to simplify the modeling of real OS functioning processes, taking into account their specifics, it is proposed to carry out preliminary development of a formalized cognitively structured aggregate-flow metamodel ("model of models") of the AS flight control process, which contains information about potentially existing capabilities for controlling the state of vehicles in various conditions of implementation of nominal and abnormal processes. Creating a conceptual metamodel allows you to make the transition from the subject formalized model to the next stages of modeling-formal-mathematical and material-functional modeling, which take into account the individual characteristics of the processes on board the AS when controlling its flight. At the same time, the problems of overcoming the complexity of the metamodel, including its dimension, are solved.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):35-60
pages 35-60 views

Neural network method of adaptive control system of imitation of physical forces

Obukhov A.D., Siukhin A.A.


This research examines the subject area of ​​physical forces simulation systems, implemented on the basis of controlled running platforms. The time spent by the control system to receive and process information about the state of the user and the system causes a software and hardware delay that prevents the system from responding in a timely manner to the user's natural movement. The control system delay problem cannot be solved using direct data of the states of the man-machine system. The aim of the presented research is to develop a new control method that allows analyzing the state of the user and the platform, forecasting his movements and organizing the process of managing the system for simulating physical forces. The method is implemented using neural networks. The scientific novelty of the method includes in the use of neural networks to solve the problems of forecasting user actions and automating decision-making to control the system for simulating physical forces. Each presented neural network is formed to perform separate tasks. The first is to create a forecast of changes in the states of a man-machine system. The second is to determine whether the forecasted state belongs to any state in the historical data. The third determines the required change in the states of the parameters of the man-machine system to achieve the forecasted state. The possibilities of using the described approach are presented on the example of a treadmill that adapts to the real parameters of the user's locomotion. The results obtained confirm a significant reduction in the complexity of the implementation of the control process after applying the neural network method. The area of application of the neural network control method is adaptive information systems and automatic control systems, in which it is necessary to minimize the system delay time and response to user locomotion.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):61-74
pages 61-74 views

Models of group poisson flows in telecommunica-tion traffic control

Likhttsinder B.Y., Bakai Y.O.


The lack of effectiveness of the use of models of self-similar processes to the analysis of queues telecommunications systems is presented. The evolution of the flow models managed by Markov’s chain is considered. The specifics of the use of Markov’s flows as models of telecommunications traffic systems are considered. Models of single-channel queueing systems with input flows that have an arbitrary correlation are presented. Generalizations of the Khinchin-Pollaczek formula are given for these systems. The perspective of the application of interval methods developed by the author for queue analysis in queueing systems with correlated input flows is shown. It is suggested to use the group Poisson extraordinary flow as a model of telecommunication traffic. Interval characteristics of the given flows are reviewed and the prospects of their application are shown. The issues of multiplexing these flows during processing in queueing systems are considered. It is demonstrated that the resulting flow is also a group Poisson flow when summing up several group Poisson flows. The conclusions are confirmed by the simulation modeling results. The examples show the validity of such models to the characteristics of real video traffic flows.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):75-89
pages 75-89 views

Electrical Engineering

Some features of an interaction of electromagnetic radiation quantums with a gravitational field and a problem of graviton

Volobuev .N., Shterenberg A.M., Kuznetsov P.K.


The problems connected to propagation of a gravitational field are considered. The law of electromagnetic radiation frequency change in gravitational field is shown. The problem of a gravitational field quantization is investigated. Energy of a graviton is found by two ways. First, on the basis of use quantum gravitational eikonal and Lagrangian of a gravitational field the energy of a solitary graviton is found. It is shown that graviton has the mass proportional to its frequency. Second, due to refusal from symmetric stresses tensor in structure of an energy-impulse tensor the quantum form of the energy-impulse tensor in Einstein's equation is found. It has allowed found the energy of a solitary graviton. Both ways of an energy graviton finding has given the identical result. It is shown that the solution of the Einstein’s equation with use of the quantum form of an energy-impulse tensor for the certain direction represents the sum of a gravitational wave and a graviton. It is found out that at approach of a graviton to the massive bodies (double stars) radiating gravitational waves there is a resonant pumping of the gravitational field energy of these bodies to the gravitons with increase in their mass and frequency. It enables registration of the gravitons with the help of the detector located near to massive bodies. The assumption is made that dark energy of a gravitational field is all set of the graviton energies of a space.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):90-109
pages 90-109 views

Optimization of the electrical technology complex for high-performance induction heating lines

Danilushkin A.I., Zhivotyagin D.A., Kibkalo S.S., Surkov D.V.


The paper discusses the design issues of a high-performance induction installation for heating ferromagnetic billets before processing on deforming equipment. Specific features of the technological process of heating ferromagnetic billets to plastic strain temperatures are noted. It is shown that in order to increase the efficiency of the process, the heating of large-sized preforms from ferromagnetic steel is advisable to be carried out in a two-frequency induction heater with two autonomous sections. A study of the heating process in a two-section heater of ferromagnetic billets was carried out taking into account the nonlinear dependence of the physical characteristics of the heated billets metal on the temperature changing during heating. The problem of minimizing the length of a two-section heater is formulated and solved taking into account energy and technological limitations. A condition for determining the optimal length of the first section is to achieve a temperature corresponding to the loss of magnetic properties in the layer equal to the depth of current penetration at the frequency of the second section power supply. The results of numerical calculation of the optimal parameters of a two-section heater are presented. It is shown that the power distribution algorithm along the length of a two-section heater is a piecewise constant function. The results of calculating the temperature distribution in the workpieces during heating are presented. The results of the study can be used to solve the problem of optimizing the structural and operational parameters of a multi-section heater.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):110-124
pages 110-124 views

Experimental study of brushless generator with integrated exciter

Zubkov Y.V., Kaurov S.Y., Vereshagin V.E.


The paper studies an integrated starter-generator based on a synchronous machine with PM excitation (ISG), used to start an internal combustion engine (ICE) of an autonomous energy facility or vehicle and supply electric energy to its consumers. The purpose of the work is to obtain a mathematical model of the starting mode in the form of a system of differential equations, its virtualization by means of the Matlab Simulink package and a diesel engine starting simulation using ISG with the study of the starting process dynamic characteristics. It is also required to carry out experimental verification of theoretical results through field tests of a prototype starter-generator to confirm the mathematical model adequacy. Difficulties in the analysis and synthesis of ISG are due to the complexity of electromechanical energy conversion processes in it and the trapezoidal nature of the magnetic field spatial distribution in the gap, which was established when solving the magnetostatic problem by the finite element method. These features make it difficult to use traditional research methods. The mathematical model of the operation starting mode, obtained under a number of assumptions that do not affect the nature of electromechanical processes, makes it possible to investigate the ICG static and dynamic characteristics during the electric start of the internal combustion engine. The ISG start-up process simulation was carried out on the basis of equations describing the starter operation using control systems both without starting current limitation and with limitation and providing a sufficient starting torque. Modeling made it possible to determine the start duration and the change of the electromagnetic torque, inverter and winding currents. A prototype ISG was designed and manufactured. Full-scale tests of the diesel engine electric start system were carried out. The results obtained confirmed the adequacy of the developed mathematical model and the possibility of its use in the study of the ISG other specific operating modes.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):125-138
pages 125-138 views

Optimal inductor design for surface hardening under conditions of interval uncertaity of process parameters

Popov A.V.


The paper is devoted to the optimal inductor design for surface hardening of steel cylindrical billets. The heating stage of surface induction hardening is considered as an object with distributed parameters, which unknowns are design characteristics of the induction installation. In real industrial conditions the main technological parameters are often defined by the intervals of their possible values. That is why, in the paper the optimal design problem under the conditions of interval uncertainty of initial billet’s temperature and thermal exchange coefficient is formulated. Solution of the formulated problem is carried out by alternance method of parametric optimization based on numerical model developed in Altair FLUX software.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):139-154
pages 139-154 views

On disadvantages of the classification of Queuing system

Likhttsinder .Y.


The features of the existing classification of queuing systems are considered, its disadvantages are shown. The main disadvantage is the lack of information about the correlation and cross-correlation properties of flows. The disadvantage of Kendall's designations is also the lack of the possibility of classifying systems by the nature of the change in the input load.

Vestnik of Samara State Technical University. Technical Sciences Series. 2020;28(3):155-157
pages 155-157 views

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