Integrated Computer Control Research Articles

Creation of an identifier database for the ammonia synthesis computer control system

The object of research is the control system of the synthesis department of the large-tonnage ammonia production unit of the AM-1360 series. An analysis of the functioning conditions of the synthesis department was carried out. The significant influence of the content of inerts in the synthesis cycle on the energy efficiency of ammonia production is shown, the optimal value of which depends both on the accepted level of prices for energy carriers and on the method of using purge gases. The need to create a computer-integrated control technology to optimize the use of purge gases is established. The function of the identifier of such a control technology is defined, namely, continuous refinement based on current information about the state of the main sections of the synthesis department, such as the synthesis column, primary and secondary condensation. The operation of these stations takes place in the conditions of seasonal and daily changes in the heat load, which causes parametric uncertainty of such parameters of the connection of the mathematical model as the concentration of ammonia in the circulating gas at the outlet of the stations listed above. Numerical assessment of these uncertainties according to the results of analytical studies for such technological objects is most often performed using stochastic approximation methods. Let’s note that the significant inertia of the objects of the synthesis department under certain conditions makes it impossible to adapt the parameter to its actual value. An algorithmic base has been created for the formation of an information array of the identifier of the computer-integrated control technology of the ammonia synthesis department, which ensures the separation of transient modes under conditions of uncertainty and allows to perform the task of identifying processes in the synthesis column, in the primary and secondary condensation units. The proposed algorithm allows to perform convergence in the department both on the general and on the component material balances. The algorithm is implemented in the MatLab application program package and tested by means of simulation based on experimental data of industrial operation of AM-1360 series ammonia synthesis units.

DATAWARE AND SOFTWARE OF THE AUTOMATED TECHNOLOGY FOR COMPUTER- INTEGRATED CONTROL OF HEAT PUMP SYSTEMS

The paper has solved a scientific and applied problem as for substantiating requirements to technical and functional characteristics of the automated technologies of computer-integrated control of heat pump systems in the heating and cooling modes owing to its dataware and software developing and testing. Following functional procedures have been taken into consideration during the dataware and software development of the computer-integrated subsystem for heating of buildings: monitoring of ambient air temperature, ground temperature, and operating modes of functional elements of the heat pump system as well as zonal monitoring of indoor air temperature; computer-integrated processing of the monitoring data; automated control of the heat pump as well as modes of zonal thermal medium supply to the building; and analysis of energy efficiency as for implementation of the proposed computer-integrated method to control systems of thermodynamic heating. It has been identified that thermal capacity of a heat pump is rather sensitive to indicators of the total heat losses of a building. If the total heat losses increase from 0.2°С/hour up to 0.5°С/hour then constant value of the thermal capacity increases by 48%. Moreover, thermal capacity of a heat pump is quite sensitive to ambient air temperature dynamics: if temperature variation is 12°С (i.e. 3°С-9 °С) then average increase in thermal capacity is 58 %. Following functional procedures have been involved during the dataware and software development of the computer-integrated subsystem for cooling of buildings: monitoring of ambient air temperature and operating modes of functional elements of the heat pump system; zonal computer-integrated monitoring of indoor air temperature; computer-integrated the monitoring data processing based upon microcontrollers; automated control of the thermal pump operating modes (i.e. heat energy outfeed and release to the main intercooler unit); and analysis of energy efficiency as for implementation of the proposed computer-integrated method to control systems of thermodynamic cooling of buildings. The abovementioned has helped identify that thermal capacity of a heat pump is rather sensitive to indicator of heat exchange with surrounding air: four times increase in heat-exchange coefficient (i.e. from 1°С/hour up to 4°С/hour) results in 20% growth of thermal capacity of the cooling subsystem system at similar ambient air temperature (it varies from 30°С up to 36 °С) if the maintained target indoor temperature is 22°С.

The Coal Quality CICS that Increases the Wear Resistance of Heat Exchanger Tubes

The paper discusses the threat of decommissioning of the thermal power plant (TPP) heat exchanger tubes because of erosion and develops a computer-integrated control system (COAL QUALITY CICS THAT INCREASES THE WEAR RESISTANCE OF HEAT EXCHANGER TUBES) for the process of distribution of steam coal flows with different indicators of abrasive materials content, which is based on fuzzy logic. The problem of rapid decommissioning of TPP heat exchanger, particularly abrasive damage to furnace screen tubes, economizer, superheater, etc. This may indicate a discrepancy between the expected fuel ash content and the actual one, as well as a high content of abrasive impurities in steam coal. The work aims to develop a CICS of the wear resistance of the heat exchange surface of a steam boiler of a coal-fired power plant by measuring and fuzzy control of the content of abrasive impurities in steam coal. The problems of damage to the equipment of the TPP boiler are investigated and a system for controlling the wear resistance of the surface by automatic fuzzy control of the quality of coal is developed. In order to investigate the effectiveness of the proposed fuzzy controller, the results were investigated in a specific example, in particular, during coal preparation and combustion in the furnace of a thermal power plant. The model results confirm the feasibility of the fuzzy control method for the system with different coal quality parameters.

STUDY OF A DISTRICT HEATING SYSTEM WATER BOILER AS A OBJECT OF CONTROL


 
 The analysis of the operating conditions of a typical district heating system, in particular, a hot water gas boiler, was carried out. It is shown that the boiler, as the main control object, operates under conditions of constant change in external heat load, which, due to their random nature, leads to a number of uncertainties. The expediency of the mathematical description of uncertainties using the stochastic method as the most tested in practical conditions is substantiated. According to the results of the passive experiment on the hot water gas boiler KVG6.5-150 of the district heating system of one of the districts of Kharkov, an array of hourly experimental data was obtained, reflecting the main performance indicators of the hot water boiler. As a result of data processing by the least squares method, a mathematical model of the boiler was obtained in the form of a linear regression equation, reflecting the relationship between the temperature of the coolant at the boiler outlet and the ambient air temperature, the temperature of the coolant at the inlet to the boiler and with the flow rates of natural gas and coolant to the boiler. The obtained regression equation was verified by Student's t-test, which confirmed the significance of all coefficients of the regression model. The practical significance of the multiple regression equation was assessed using the coefficient of determination. The quality of the multiple regression equation as a whole was assessed using Fisher's F-test. Since parallel surveys were not conducted, instead of checking the adequacy, the quality of the approximation of the experimental points by the accepted regression equation was assessed, that is, it was checked whether this equation makes sense. Such a test was carried out by comparing the residual variance and the variance relative to the mean. The calculation results showed that the value of the coefficient of determination significantly exceeds the allowable value, and the actual value of the Fisher criterion significantly exceeds the table value. The obtained indicators led to the conclusion that the relationship between the variables in the regression model is significant, and the proposed stochastic method and the multiple linear regression equation can be used to make decisions in the process of synthesizing the technical structure of a computer-integrated control system for objects of a district heating system.
 
 
 
 
 

Automated solid fuel quality control and monitoring system

The article describes the development of a computer-integrated coal quality management system that allows to increase the service life of heating surfaces in boilers of coal-fired power plants. The need for such a system arises due to erosion caused by abrasive impurities in coal, which leads to deterioration of the boiler infrastructure. Existing methods are mostly manual, time-consuming and error-prone. The aim of the work was to increase the service life of the surface wear resistance of heat exchange tubes of a steam generator of a thermal coal-fired power plant by synthesizing and analyzing a computer-integrated coal quality management system by distributing coal flows between different coal supply sources, unloading conditions and coal quality inspection from suppliers to minimize costs. To achieve this goal, a mathematical model was developed that describes the boiler unit in terms of ash flows in the form of a system of equations. A computer-integrated coal quality control system has been developed that allows to increase the service life of heating surfaces of power boilers by distributing coal flows between coal supply sources and conditions of unloading and checking the quality of coal from suppliers to minimize costs. A computational experiment was conducted to test the operation of the computer-integrated control system and confirm its effectiveness. The results proved the value of the developed computer-integrated control system for increasing the service life of the boiler unit's heating surfaces by timely responding to changes in the quality of coal from different suppliers. It was found that with a computer-integrated control system, the service life of the pipes could be more than doubled (from 3.06 years to 7.39 years). Overall, the introduction of a computer-integrated control system is a transformational solution for managing the distribution of costs between fuel and equipment repair costs. The integrated system, together with the use of mathematical modeling and computational experiments, offers a comprehensive approach to monitoring, predicting, and controlling the factors that affect the durability of heat exchanger tubes. This research makes a significant contribution to the power industry, potentially transforming maintenance and life extension practices for critical infrastructure in thermal power plants. Further researchis needed to refine the system and explore its wider applicability in different operational scenarios.

Computer-integrated control system for electrophysical methods of increasing plant productivity

Computer-integrated control system for electrophysical methods of increasing plant productivity

НЕЧІТКА ЕКСПЕРТНА СИСТЕМА ДЛЯ КЕРУВАННЯ ТЕМПЕРАТУРОЮ ПОВІТРЯ У ПРИМІЩЕННЯХ ТОРГОВЕЛЬНО-РОЗВАЖАЛЬНОГО ЦЕНТРУ

Abstract The article presents the stages of developing a fuzzy expert system for the operator of a heating point of a shopping and entertainment center. The principle of operation of the air heating system of the mall is shown, implemented using computer-integrated control with a SCADA system. For the effective operation of the air temperature control system in different areas of the mall, functions for belonging to comfort zones have been developed in terms of visitors and the requirements of sanitary standards. It is indicated that typical air temperature stabilization controllers cannot always provide the desired mode due to the influence of a large number of uncontrolled disturbances on the control system. In this case, in the absence of additional blocks for adapting control algorithms, it becomes expedient to remotely control the operator using a mnemonic diagram of the ventilation process. And to improve the efficiency of the process of remote control of thermal equipment, an expert system was proposed that implements the algorithm of I. Mamdani, to control the coolant flow valves. The controller receives information from the outdoor air and air temperature sensors in the control area of the mall. After processing the signals from the sensors, the controller transmits information to a computer with an expert system. Depending on the temperature and season of the year, the program calculates the optimal position of the valve (in percentage of stroke) for the flow rate of the coolant and recommends installing it to the operator. Also, it is shown that in the process of developing a fuzzy expert system, it is recommended to choose the Gaussian type of membership functions; minimal number of terms - sets - three functions of dependency; weight coefficient of each rule in the knowledge base is the same and equal to 100; the method of defasification is the method of the center of gravity. It is indicated that the introduction of expert advice to operators can also lead to a reduction in the response time to emergency situations up to 90% increase in the reliability of the equipment as a whole.

АВТОМАТИЗОВАНЕ КЕРУВАННЯ СИСТЕМОЮ ТЕПЛОПОСТАЧАННЯ ЗІ ЗМІННОЮ СТРУКТУРОЮ ПО ЗНАЧЕННЯМ ЦІЛЬОВОЇ ФУНКЦІЇ ОПТИМІЗАЦІЙНОЇ ЗАДАЧІ

Abstract. Object-oriented models of the object and the control system, based on data ware and software improvement, for elements of the computer-integrated control system designed for a heat supply system, have been worked out. Also, a complex criterion of optimal control of the heat supply system structure on the basis of engineering-and-economic performance, as well as control algorithms defining the optimal structure of the system and using genetic algorithms, have been proposed. Research of the control efficiency using a simulation model of the heat supply system has been carried out. Keywords: computer-integrated control system, structure variation control, optimal control criterion, object-oriented analysis, engineering-and-economic performance, genetic algorithm.

MODELS AND METHODS FOR IMPROVING THE OPERATION OF THE ENERGY FACILITY CONTROL SYSTEM

This article is devoted to improving methods and models for a computer-integrated control system (CICS) that monitors the wear of heat exchange surfaces of pipes in steam boilers at coal-fired thermal power stations (TPP), in particular for coal with unknown abrasive composition. The system uses real-time coal quality data to 1manage the abrasive, optimize coal distribution, and verify coal quality to reduce costs. It is described that the difficulties faced by the global coal industry are related to quality, price and environmental issues, and the transition to sustainable energy is complicated by this diversity. Efficient power generation depends on accurate identification of fuel composition and minimizing damage from abrasive impurities in the fuel of heat exchangers. Despite the existing analytical methods, there is a need for improved diagnostic technology, which involves the integration of automated systems to improve efficiency and sustainability. The paper presents a mathematical model that calculates the effect of different types of coal and impurities on the wear of heat exchange tubes, maximizing service life and minimizing costs. It includes a Cochran sampling rule to improve coal quality control. An automated coal quality management method was also developed to reduce wear from abrasive coal impurities. It includes a stepwise supplier selection and stock utilization method, enhancing wear control using the Cochran stepwise sampling method. In addition, a fuzzy logic-based control device distributes the flow in such a way as to ensure satisfactory coal quality, emphasizing the need for continuous system monitoring. A model-based CICS has been developed that controls coal flow based on real-time impurity identification, resulting in significant cost savings and extended overhaul intervals. Computational experiments confirm that the CICS can more than double the service life of heat exchange tubes by maintaining a satisfactory thickness, thereby postponing repairs and reducing operating costs. Overall, this article presents a comprehensive approach to managing and optimizing heat exchanger tube wear at TPP using modelling, real-time data analysis, and automated control systems to improve efficiency and sustainability.

Development of Models and Methods for Automated Control of Heat Supply System with Optimization of Technical Means Structure

Analysis of the controlled object, as well as methods and models applied for controlling the heat supply process in a city and urban districts has been carried out. Simulation models of the controlled object functioning in the presence of alternative energy flows with different costs have been developed. The criteria and objective function for optimizing the city’s heat supply process have been synthesized and substantiated. The task of optimizing the process of heat supply in urban districts has been solved based on the transition from the structural optimization of the controlled object to managing the price structure for the energy flows offered to the consumer. The computer-integrated control systems have been implemented for the proposed facilities and their effectiveness has been defined.

АВТОМАТИЗОВАНЕ КЕРУВАННЯ СИСТЕМОЮ ТЕПЛОПОСТАЧАННЯ ЗІ ЗМІННОЮ СТРУКТУРОЮ ПО ЗНАЧЕННЯМ ЦІЛЬОВОЇ ФУНКЦІЇ ОПТИМІЗАЦІЙНОЇ ЗАДАЧІ

Abstract. Object-oriented models of the object and the control system, based on data ware and software improvement, for elements of the computer-integrated control system designed for a heat supply system, have been worked out. Also, a complex criterion of optimal control of the heat supply system structure on the basis of engineering-and-economic performance, as well as control algorithms defining the optimal structure of the system and using genetic algorithms, have been proposed. Research of the control efficiency using a simulation model of the heat supply system has been carried out. Keywords: computer-integrated control system, structure variation control, optimal control criterion, object-oriented analysis, engineering-and-economic performance, genetic algorithm.

Development of hardware and software support of computer-integrated technology of complex of secondary condensation of ammonia production

The object of research is the technological complex of secondary condensation (TCSC) and the control system of a typical ammonia synthesis unit of the AM-1360 series. The analysis of the conditions of its functioning and hardware and technological design was carried out. The coordinates of the control vector are determined. The features of the proposed functional diagram and the necessary algorithmic software for the computer-integrated control technology of the TCSC with a correction subsystem for decision-making under uncertainty are established. The implementation of the proposed solutions is complicated by the use of the information and control complex TDC-300 (USA) with closed-type software installed on the existing ammonia synthesis units. The need for such a control complex to implement a decision-making subsystem under conditions of uncertainty is shown to supplement the existing control system with hardware and software of an «open» type. A computer-integrated TCSC technology based on a three-level hierarchical structure has been created. The implementation of the zero and first levels of such a structure form single software and hardware complex consisting of a programmable logic controller and an automated operator's workplace based on an industrial computer with installed software. A software implementation of decision-making on the correction of the coordinates of the control vector by additional hardware and software based on the VIPA logic controller and the Zenon SCADA system was made. A scheme of network information flows has been implemented, which illustrates the functioning of the decision-making correction subsystem in the general structure of the TCSC computer-integrated control technology. Implementation of the developed system allows, under the existing uncertainties, to reduce the secondary condensation temperature by an average of 3 °C, which ensures an annual reduction in natural gas consumption by 1 million nm3. The proposed approach to the possibility of combining «open» and «closed» type hardware and software can be applied in other industries.

Апаратно-програмна реалізація інтелектуальної комп’ютерно-інтегрованої системи контролю та прогнозування величини струму витоку електрообладнання тваринницького приміщення

. The development of advanced protection systems and ways to reduce electricity losses during its transportation by power lines is an urgent scientific problem. The main source of leakage current in livestock facilities are electric motors, which are necessary to ensure the technological process. Humidity of the electric motor has an extremely negative effect on the condition of the motor insulation. The purpose of the study is to develop the structure of a computer-integrated system that monitors and predicts the values of motor leakage current to prevent its impact on animal living conditions and dangerous consequences for living organisms with hardware-software implementation of computer-integrated control system based on SCADA Trace Mode. T his article considers the possible hardware and software implementation of an intelligent computer-integrated control system and forecasting the value of the leakage current of electrical equipment of livestock premises. To provide automated real-time control, a SCADA system with appropriate software has been developed. This software is installed on computers and, to communicate with the object, uses I/O drivers or OPC/DDE servers. Program code can be written in a programming language (such as C++) or generated in an automated design environment. The modular product SCADA Trace Mode was used for technical and software implementation of the developed system. Key words: leakage current, SCADA, SCADA Trace Mode, control, network

Studying additional measurement errors from control tools using an integral functional method

Our research has established that under industrial conditions the correction to the result of current measurements when an influencing parameter deviates from the rated value is rarely introduced. In a general case, the procedure for determining an additional measurement error implies that the measured values for an influencing parameter are applied to determine the degree of its deviation while a correction to the current measurement result is calculated as the product of this degree by its rated value.In a general case, a procedure for determining an additional measurement error includes two stages. At the first stage, the measured values for an influencing parameter are used to determine the degree of its deviation from the rated value. At the second stage, correction is calculated as the product of this degree by the rated value for an additional error.Such a technique to calculate a correction is time consuming and insufficiently precise, as it does not take into consideration the non-linear dependence of the additional error on a change in the influencing parameter, as well as the current value for the output signal of control tool. To determine the actual value for an influencing parameter and the additional measurement error under industrial operation of control tools, an integral functional method has been proposed. The method implies determining the difference of areas under the nominal and actual acreage static characteristics, limited to a range of measurement. The difference of areas is a function of the output signal of a control tool, a measured parameter and a change in the influencing parameter. It has been shown that the proposed method makes it possible to calculate the actual values for a technological parameter based on its measured and influencing parameters only. We have established regularities between the actual value for a measured parameter, the current value for the output signal from a control tool, and the measured value for an influencing parameter. The proposed method is important and valuable in the operation of computer-integrated control systems of technological parameters, as it makes it possible to determine the actual values for a measured parameter based on relevant algorithms without calculating corrections.

Intellectual analysis in the management of the production entomophages

Purpose. Improving the efficiency of entomophage production by optimizing the management technological processes using intellectual analysis. Methods. To develop an intellectual system for managing the production of entomophages, the methods of systemic, economic and mathematical analysis, fuzzy inference, experimental studies in laboratory production have been used. Results. An intellectual computer-integrated control system for the laboratory production of entomophage Habrobracon hebetor is developed; the lower level is represented by the automatic subsystem of control of the abiotic parameters of the production of entomological products with the SCADA program, the upper – an intellectual subsystem of decision-making. The criteria of system efficiency are determined. The calculation of indicators of the effectiveness of the implementation of an intelligent system based on the coefficient of profitability of fixed assets (ROFA), the coefficient of economic efficiency of capital investments and the period of full payback of the system was made. Conclusions. An intellectual control system for the production of entomophages is developed, which automatically generates control actions on the development of entomocultures; in an automated implements profit management strategies of production, minimizing energy consumption in conditions of uncertainty due to the influence of natural perturbations (change in ambient temperature). The full payback period of the system is 2.2 years. Keywords: intellectual analysis, control system, entomophage production, profit, efficiency, energy consumption

International Conference Information Technologies in Business and Industry 2018

PrefaceThe International Conference «Information Technologiess in Business and Industry» 2018 (ITBI2018) was held in Tomsk, Russia on January 17-20, 2018.The Conference also provides an interdisciplinary forum for researchers, practitioners and scholars to present and discuss the most recent innovations and developments in the field of new information technologies and modeling methods, techniques and technologies of the automated mechanical engineering.The four-day Conference brought together the specialists from different countries and organizations and provided an excellent opportunity to exchange knowledge, make oral contributions and poster presentations, and initiate discussions on the topics that are of interest to the Conference participants.The selected papers of the Conference cover a wide range of technical areas and modern aspects of the information technologies and modeling methods, integrated computer control systems in mechanical engineering, numerical simulation of applied problems.

Research of opportunities for adaptation of computer-integrated mixture preparation systems to conditions of foundries in Ukrainian enterprises producing wear-resistant cast iron

The problems associated with the possibility of adaptation of modern computer-integrated control systems for control of imported mixture preparation equipment to the conditions of the foundries in Ukrainian enterprises are considered. It is emphasized that ensuring the given quality of a mixture is an important factor in determining the performance characteristics of wear-resistant cast iron castings. It is shown that the use of modern imported mixture preparation systems suggests the possibility of supplementing by models and algorithms of Ukrainian developments in the synthesis of molding compounds, and optimal control of mixture preparation processes. Proposed options that can complement the QualiMaster AT1/ SandReport/ SandExpert system are a variant of its adaptation to the conditions of foundries of the Ukrainian enterprises. These options are based on mathematical models «mixture composition – mixture properties» in the form of regression equations and algorithms for optimal control of mixture preparation sections. The use of these solutions provides the ability to improve performance, particularly durability of wear-resistant cast iron castings, working in conditions of intensive abrasive friction. This is due to the fact that factor in improving the durability is high quality of working surfaces formed at the «casting surface – molding sand» interface.

Control and Information Systems for the National Ignition Facility

Orchestration of every National Ignition Facility (NIF) shot cycle is managed by the Integrated Computer Control System (ICCS), which uses a scalable software architecture running code on more than 1950 front-end processors, embedded controllers, and supervisory servers. The ICCS operates laser and industrial control hardware containing 66 000 control and monitor points to ensure that all of NIF’s laser beams arrive at the target within 30 ps of each other and are aligned to a pointing accuracy of less than 50 μm root-mean-square, while ensuring that a host of diagnostic instruments record data in a few billionths of a second. NIF’s automated control subsystems are built from a common object-oriented software framework that distributes the software across the computer network and achieves interoperation between different software languages and target architectures. A large suite of business and scientific software tools supports experimental planning, experimental setup, facility configuration, and post-shot analysis. Standard business services using open-source software, commercial workflow tools, and database and messaging technologies have been developed. An information technology infrastructure consisting of servers, network devices, and storage provides the foundation for these systems. This paper is an overview of the control and information systems used to support a wide variety of experiments during the National Ignition Campaign.

Research of questions of control automation of the city district heating system with the object structure optimization

The paper proposes a new solution to the problem which lies in improving the methods and models for automatic control of the city district heating system to increase economic efficiency by target change of the control object structure. The analysis of the control object, methods and models used in the heating control of the city and districts was performed. Simulation models of the control object, which operate in the presence of alternative energy flows, differing in cost were developed. Optimization criteria and objective function of the city district heating were synthesized and justified. The heating optimization problem of districts by switching from the structural control object optimization to the price structure control of energy flows, proposed to the consumer was solved. Computer-integrated control systems and control of the proposed objects was practically implemented in order to assess their effectiveness.

Computer energy-saving technologies for building life-support systems control

Energy saving in building life-support systems is a complex problem of global concern. As a result of the studies, functional diagrams of computer-integrated control systems for technological processes of traditional (upgrading of existing) and alternative (development of new) heating systems are developed. Developed functional schemes allow to improve the operating efficiency of building life-support systems and save the material and energy resources in conditions of scarcity for: • modernized individual heat point with heating and hot water treatment systems of the building through the energy-saving efficiency improvement, air temperature control in each room individually, heat energy consumption accounting for each apartment that encourages timely payment by tenants; • solar collector systems through the air temperature control in each room individually, including in very hot summer (air conditioning), energy saving; • systems for obtaining and using geothermal energy for four heat transfer cycles through creating favorable conditions in premises (especially office premises), energy saving. Saving material and energy resources through applying computer energy-saving technologies for building life-support systems control promotes solving an urgent problem of global scale - energy saving.