Integrated Computer Control System Research Articles

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

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.

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 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.

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

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.

The Design of Computer Integrated Control System for Electron Beam Welder

Based on computer and PLC control technology, the control system for electron beam welder has been studied in this paper. By using PLC control technology to implement the intelligent control (IC) in welding process and adopting the high-frequency inverter technology, to realize the high-voltage interlock protection, the quality of electron beam current spot as well as the welding technology has been improved. Concerning the requirements on the technical and process, the design of computer communication and PLC application software demonstrate the feasibility of this method.

The shaping of a national ignition campaign pulsed waveform

The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory is a stadium-sized facility containing a 192 beam, 1.8MJ, 500TW ultraviolet laser system used for inertial confinement fusion research. For each experimental shot, NIF must deliver a precise amount of laser power on the target for successful and efficient target ignition, and these characteristics vary depending on the physics of the particular campaign. The precise temporal shape, energy and timing characteristics of a pulsed waveform target interaction are key components in meeting the experimental goals. Each NIF pulse is generated in the Master Oscillator Room (MOR) using an electro-optic modulator to vary the intensity of light in response to an electrical input. The electrical drive signal to the modulator is produced using a unique, high-performance arbitrary waveform generator (AWG). This AWG sums the output of 140 electrical impulse generators, each producing a 300ps pulse width Gaussian signal separated in time by 250ps. By adjusting the amplitudes and summing the 140 impulses, a pulsed waveform can be sculpted from a seed 45ns square pulse. Using software algorithms written for NIF's Integrated Computer Control System (ICCS), the system is capable of autonomously shaping 48 unique experimental pulsed waveforms for each shot that have demonstrated up to 275:1 contrast ratio with ±3% absolute error averaged over any 2ns interval, meeting the stringent pulse requirements needed to achieve ignition. In this paper, we provide an overview of the pulse shaping system, software algorithms and associated challenges that have been overcome throughout the evolution of the controls.

National Ignition Facility and managing location, component, and state

The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory is a stadium-sized facility that contains a 192-beam, 1.8-MJ, 500-TW, ultraviolet laser system coupled with a 10-m diameter target chamber. There are over 6200 Line Replaceable Units (LRUs) comprised of more than 104,000 serialized parts that make up the NIF. Each LRU is a modular unit typically composed of a mechanical housing, laser optics (glass, lenses, or mirrors), and utilities. To date, there are more than 120,000 data sets created to characterize the attributes of these parts. Greater than 51,000 Work Permits have been issued to install, maintain, and troubleshoot the components. One integrated system is used to manage these data, and more. The Location Component and State (LoCoS) system is a web application built using Java Enterprise Edition technologies and is accessed by over 1200 users. It is either directly or indirectly involved with each aspect of NIF work activity, and interfaces with ten external systems including the Integrated Computer Control System (ICCS) and the Laser Performance Operations Model (LPOM). Besides providing business functionality, LoCoS also acts as the NIF enterprise service bus. In this role, numerous integration approaches had to be adopted including: file exchange, database sharing, queuing, and web services in order to accommodate various business, technical, and security requirements. Architecture and implementation decisions are discussed.

CORBA-based distributed software framework for the NIF integrated computer control system

The National Ignition Facility (NIF), currently under construction at the Lawrence Livermore National Laboratory, is a stadium-sized facility containing a 192-beam, 1.8 MJ, 500 TW, ultra-violet laser system together with a 10-meter diameter target chamber with room for nearly 100 experimental diagnostics. The NIF is operated by the Integrated Computer Control System (ICCS) which is a scalable, framework-based control system distributed over 800 computers throughout the NIF. The framework provides templates and services at multiple levels of abstraction for the construction of software applications that communicate via CORBA (Common Object Request Broker Architecture). Object-oriented software design patterns are implemented as templates and extended by application software. Developers extend the framework base classes to model the numerous physical control points and implement specializations of common application behaviors. An estimated 140,000 software objects, each individually addressable through CORBA, will be active at full scale. Many of these objects have persistent configuration information stored in a database. The configuration data is used to initialize the objects at system start-up. Centralized server programs that implement events, alerts, reservations, data archival, name service, data access, and process management provide common system wide services. At the highest level, a model-driven, distributed shot automation system provides a flexible and scalable framework for automatic sequencing of workflow for control and monitoring of NIF shots. The shot model, in conjunction with data defining the parameters and goals of an experiment, describes the steps to be performed by each subsystem in order to prepare for and fire a NIF shot. Status and usage of this distributed framework are described.

Status of the National Ignition Facility Integrated Computer Control System (ICCS) on the path to ignition

The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory is a stadium-sized facility under construction that will contain a 192-beam, 1.8-MJ, 500-TW, ultraviolet laser system together with a 10-m diameter target chamber with room for multiple experimental diagnostics. NIF is the world's largest and most energetic laser experimental system, providing a scientific center to study inertial confinement fusion (ICF) and matter at extreme energy densities and pressures. NIF's laser beams are designed to compress fusion targets to conditions required for thermonuclear burn, liberating more energy than required to initiate the fusion reactions. NIF is comprised of 24 independent bundles of eight beams each using laser hardware that is modularized into more than 6000 line replaceable units such as optical assemblies, laser amplifiers, and multi-function sensor packages containing 60,000 control and diagnostic points. NIF is operated by the large-scale Integrated Computer Control System (ICCS) in an architecture partitioned by bundle and distributed among over 800 front-end processors and 50 supervisory servers. NIF's automated control subsystems are built from a common object-oriented software framework based on CORBA distribution that deploys the software across the computer network and achieves interoperation between different languages and target architectures. A shot automation framework has been deployed during the past year to orchestrate and automate shots performed at the NIF using the ICCS. In December 2006, a full cluster of 48 beams of NIF was fired simultaneously, demonstrating that the independent bundle control system will scale to full scale of 192 beams. At present, 72 beams have been commissioned and have demonstrated 1.4-MJ capability of infrared light. During the next 2 years, the control system will be expanded in preparation for project completion in 2009 to include automation of target area systems including final optics, target positioners and diagnostics. Additional capabilities to support fusion ignition shots in a National Ignition Campaign (NIC) beginning in 2010 will include a cryogenic target system, target diagnostics, and integrated experimental shot data analysis with tools for data visualization and archiving. This talk discusses the current status of the control system implementation and discusses the plan to complete the control system on the path to ignition.