Equipment Of Thermal Power Plants Research Articles

Application Research of Multiple Detection Technology in Equipment Fault Diagnosis

With the development of detection technology, there are more and more detection methods for devices[1,2]. Multiple detection technologies[3,4] make targeted detection of devices to make the state judgment of devices more comprehensive. In the detection of auxiliary equipment in thermal power plants, vibration detection is generally used, but infrared and ultrasonic detection technology analyzes the fault state diagnosis of auxiliary equipment from another aspect, which plays a very important role. Multi-tech detection and mutual verification more and more methods are applied to equipment detection.

Exergetic evaluation of a thermal station “Central’naya” and Vladivostok thermal station – 2

The article discusses the issue of increasing the efficiency of the main equipment of thermal power plants. Currently in power systems, different types of power plants are used. The projecting and choice of the power plant is performed mainly based on criterion of efficiency. The primary indicator is the thermic efficiency calculated traditionally by heat balance method. The current article proposes the use of exergy method of determining of energy efficiency, allowing performing relative (exergetic efficiency) and absolute evaluation of the degree of thermodynamic perfection of the system. The exergy losses in elements of the equipment were calculated on the example of a gas turbine installation.

A formation of an approach to solving the problem of selecting the composition of the included generating equipment

The article deals with the method of formation of optimization models for calculation of modes of operation of thermal power plants, as well as the software package on which the optimization models are formed. The formed model allows to calculate the optimal combination of the whole set of combinations of compositions and modes of operation of the thermal power plant equipment.

Improvement of Methods for Predicting the Generation Capacity of Solar Power Plants: the Case of the Power Systems in the Republic of Crimea and City of Sevastopol

The construction and operation of large solar power plants (SPPs) and the dependence of their production on light and other meteorological factors leads to a strong dependence of the operation modes of the Republic of Crimea and Sevastopol power system on meteorological factors. Today, given that the share of solar power plants is about 30% of the total installed capacity, it is necessary to solve the problems that have a great impact on the power system operating modes. With large output capacity of the solar power plant, the operator has to give commands to turn off the generating equipment of thermal power plants. In power systems with a large share of solar generation, it is necessary to solve this problem by improving the generated power predicting methods, as it will reduce the dependence of operating modes on weather factors and increase the reliability of the power system. The paper discusses the use of hybrid predicting methods that imply taking into account the possibility of the weather scenarios simulation, advanced cloud-based image processing technology, and close-to-real-time cloud motion surveillance cameras. There was an experimental software created that selects coefficients of set configuration time series. In combination with the conservative methods, it makes predicting the SPP Perovo output more accurate. Taken together, the chosen methods of predicting solar power generation capacity in the power system of the Republic of Crimea and Sevastopol ensure not only stability of the power system as a whole, but also the maximum efficiency of power plants, allow to accelerate the integration of solar power plants into the power system, and have positive effects on the environment.

Research of dynamic characteristics of signals for calculation of technical and economic indicators and increase in power efficiency of the equipment of thermal power plant

The article is devoted to questions of effective management of the power equipment of a thermal power plant in the conditions of quickly changing operating modes of power systems. The results of a research of dynamic characteristics of the signals used for calculation of technical and economic indicators of the generating sources are given. The analysis is carried out and an assessment of a possibility of increase in efficiency of updating of the current values of technical and economic indicators on the example of package boilers of block and not block thermal power plants is given. The practical recommendations of use of a new approach of measurement of dynamic characteristics of signals for calculation of efficiency of the boiler and change of parameters of operation of the power equipment are formulated.

Научная методика создания капиллярно-пористых систем охлаждения для элементов теплоэнергооборудования электростанций

We investigated critical heat flux phenomena in metallic and porous structures characterised by low thermal conductivity. These structures are used to cool various thermal power plant equipment; their operation involves both gravity and capillary forces. The paper describes the failure mechanism in metallic steam generator surfaces and poorly thermally conductive low-porosity coatings made of natural mineral media (such as granite). We determined how heat flows depend on their duration and penetration depth of thermal disturbance. Tubular porous systems are less bulky and feature high intensity, higher thermal conductivity and reliability. We show that for granite coatings the maximum thickness of the particles detached due to compression forces is (0.25...0.3)·10--2 m. The compression curve sections that govern detachment of particles larger than 0.3·10--2 m are shadowed by the melt curve for high heat flows and short exposure times and by the tension curve in the case of low heat flows and short periods of time. The investigation should help us to design porous coatings usable in cooling systems.

DEVELOPMENT OF AN EXPERIMENTAL-THEORETICAL MODEL FOR THE NOISE FIELD OF THERMAL POWER PLANT EQUIPMENT

This article studies problems of forecasting of noise pollution by thermal power plant equipment, industrial boilers, etc. An acoustic model of a residential area, exposed to power plant equipment noise nuisance, has been developed by means of AWM “Acoustics” software using obtained data. Practical application of the experimental-theoretical model for the noise field was demonstrated for efficiency estimation of the proposed engineering solution to noise reduction.

National and International Guidelines for the Use of Reagents Containing Film-Forming Amines for the Organization of TPP Water Chemistry Regime

The reliability and economy of thermal power plant equipment, including combined-cycle plants, are affected by corrosion of structural materials and deposit formation in the water-steam circuit. To reduce the rate of these processes, coolant treatment is used. Ammonia, hydrazine, phosphates, etc. have been traditionally used as reagents. Recently, much attention has been paid to the use of water chemistry with the addition of complex reagents based on film-forming amines, not only for the equipment protection during the established operation mode but also for start-stops and preservation. Such water chemistry regimes are used not only in Russia but also in other countries for steam turbine and combined-cycle TPP, including biomass TPPs. The International Association for the Properties of Water and Steam, uniting specialists from all over the world, developed a guideline in 2016 for the use of such reagents based on theoretical studies and years of operational experience in power equipment in 21 countries. The review of domestic and international guidelines containing conditions for the use of film-forming amines and amine-based reagents for the organization of TPP water chemistry regimes for steam turbines and combined-cycle plants is presented.

Effects of blade thickness on hydraulic performance and structural dynamic characteristics of high-power coolant pump at overload condition

As an indispensable equipment in thermal power plants, the high-power coolant pump is necessary for high hydraulic performance with good structural safety for transferring of heat produced by fuels. However, the design of blade thickness for coolant pump especially at the off-design condition is still empirical and arbitrary. In the present work, the hydraulic performance, internal flow pattern, and structural response arising from the variations of blade thickness in coolant pump have been investigated using computational fluid dynamics and fluid–structure interaction methods. The numerical results have been verified by experimental performance and found to be good. To improve the accuracy of head calculation at the overload condition, a modified equation is proposed with the help of multi-island genetic algorithm and the average deviation is reduced from 58.50 to 1.59%. With the blade thickening process, the hydraulic performance is gradually deteriorated especially at the overload condition, and the flow behavior is changed with the proportion of high velocity near the pressure surface enlarging, the proportion of low velocity near the suction surface decreasing, and the pressure fluctuation intensity rising. Besides, increasing the blade thickness beyond 23.0 mm, the stress reduction is not effective. However, it helps to increase the natural frequency for suppressing the resonance. Finally, considering the optimal hydraulic and structural performances, the blade thickness is optimized to 23.0 mm.

Numerical simulation of environmentally-safe technologies in power engineering

One of the effective tools of solving engineering problems is the mathematical simulation of newly built and reconstructed industrial equipment. A necessity of solving identical problems fully belongs to ge-nerating equipment of thermal power plants too, which makes the use of methods of mathematic simulation quite a promising one in the course of designing power-generating units. The work presents the results of simula-tion and subsequent incorporation of the method of low-temperature vortex fossil solid-fuel combustion. Based on the developed algorithms and calcu-lation program the assessment of environmental indicators of reconstructed boiler equipment has been carried out and compliance with environmental standards with respect to the level of emissions of gaseous pollutants into environment confirmed. The incorporation of the method being considered into power-generating production has made it possible to reduce emissions of gaseous nitrogen oxides during combustion of coals of different types by 30%.

Evaluation of Degradation Progress and Rationalization of Inspection Frequency of Thermal Power Plant Equipment by using Markov Chain Model

Evaluation of Degradation Progress and Rationalization of Inspection Frequency of Thermal Power Plant Equipment by using Markov Chain Model

ECONOMIC EFFICIENCY OF MODERNIZING THE EQUIPMENT FOR THERMAL POWER PLANTS

The subject matter of the study is the economic efficiency of modernizing equipment for thermal power plants (TPP). The goal of the study is to identify the economic efficiency of modernizing the equipment of the TPP basing on new technology and taking into account cost minimization and environmental requirements. The subject of the study is the theoretical and practical aspects of the economic efficiency of equipment modernization. To find a solution of this problem, the feasibility analysis was used to determine the current state of TPP equipment and the indicators of the parameters of old and new equipment as well as to introduce new equipment, which enables burning low-grade and waste coal in a circulating fluidized bed (CFB). The issues of energy as the industry that covers energy resources, extraction, transformation, transfer and use of various types of energy are considered. The features of an electric power station, as a set of installations, equipment and tools which are used directly for producing electric energy are highlighted as well as the necessary facilities that are located on a designated area. The features of the structure of the technology of thermal power plants are illustrated. The place of thermal power plants in the structure of power engineering is considered. The available problems of thermal power plants are revealed. The solution of problems of low efficiency, the deterioration and ageing of thermal power plants equipment is suggested. The indicators of the equipment of thermal power plants are given. The advantages and disadvantages of the old technologies used in thermal power plants of Ukraine are studied. The disadvantages of outdated equipment such as damage and constant need for reconstruction are regarded. The mechanism of introducing the new technology of the circulating fluidized bed (CFB) in comparison with the traditional flaring at domestic and foreign thermal power plants is analyzed. The advantages and disadvantages of the CFB technology in comparison with traditional flaring are considered. The results of the feasibility study are presented; these results provide the basis for determining the most promising objects for the implementation of this technology while retooling power plants. The effect of modernizing the equipment of thermal power plants is proved. Solutions for improving the cost-effectiveness of thermal power plants are suggested. The results of the obtained decision within this study are illustrated.

Use of Modern Information Technologies to Improve Energy Efficiency of Thermal Power Plant Operation

The report shows the need for the development and implementation of new approaches to operational management of the modes and the efficiency of the equipment of thermal power plants on the basis of modern information technologies to significantly improve the economy of operation of thermal power plants by complex solution of the tasks of block and station levels. The proposed approach is the adjustment of measured parameters, ensuring the accuracy of all the main parameters required for material, heat and energy balances for each unit and the station in general.

Development of an Algorithm for Identification and Confirmation of Fault in Thermal Power Plant Equipment Using Condition Monitoring Technique

Thermal Power plant (TPP) is biggest source of power in India. About 65% of electricity is generated by using thermal power plant. The equipment of TPP runs for 24x7 days through the year. The fault of TPP equipment needs to identify at early stage before the breakdown of system or unit. The maintenance functions of TPP should be optimized carefully by selecting suitable maintenance strategy at least cost. Identification and confirmation of fault in TPP equipment is very important step for decision making. It helps to optimize the maintenance activity. This paper proposes an algorithm for use of co-ordinated condition monitoring approach for identification and confirmation of fault. The objective of this study is to improve the availability and heath of critical equipment of Dahanu Thermal Power Station (DTPS) located in western region of India.

Experience with Certification Testing of Thermal Power Plant Equipment

Experience with certification testing of steam and combined cycle power plant equipment is described and information is provided on major studies by VTI on the operation of the equipment in frequency and power control modes.

Practical application of the benchmarking technique to increase reliability and efficiency of power installations and main heat-mechaniс equipment of thermal power plants

Data on the comparative analysis variants of the quality of power installations (benchmarking) applied in the power industry is systematized. It is shown that the most efficient variant of implementation of the benchmarking technique is the analysis of statistical distributions of the indicators in the composed homogenous group of the uniform power installations. The benchmarking technique aimed at revealing the available reserves on improvement of the reliability and heat efficiency indicators of the power installations of the thermal power plants is developed in the furtherance of this approach. The technique provides a possibility of reliable comparison of the quality of the power installations in their homogenous group limited by the number and adoption of the adequate decision on improving some or other technical characteristics of this power installation. The technique provides structuring of the list of the comparison indicators and internal factors affecting them represented according to the requirements of the sectoral standards and taking into account the price formation characteristics in the Russian power industry. The mentioned structuring ensures traceability of the reasons of deviation of the internal influencing factors from the specified values. The starting point for further detail analysis of the delay of the certain power installation indicators from the best practice expressed in the specific money equivalent is positioning of this power installation on distribution of the key indicator being a convolution of the comparison indicators. The distribution of the key indicator is simulated by the Monte-Carlo method after receiving the actual distributions of the comparison indicators: specific lost profit due to the short supply of electric energy and short delivery of power, specific cost of losses due to the nonoptimal expenditures for repairs, and specific cost of excess fuel equivalent consumption. The quality loss indicators are developed facilitating the analysis of the benchmarking results permitting to represent the quality loss of this power installation in the form of the difference between the actual value of the key indicator or comparison indicator and the best quartile of the existing distribution. The uncertainty of the obtained values of the quality loss indicators was evaluated by transforming the standard uncertainties of the input values into the expanded uncertainties of the output values with the confidence level of 95%. The efficiency of the technique is demonstrated in terms of benchmarking of the main thermal and mechanical equipment of the extraction power-generating units T-250 and power installations of the thermal power plants with the main steam pressure 130 atm.

Optimizing the Operating Conditions of Boilers of Thermal Power Plants Using the Criterion of Minimum Power Losses

This scientific paper gives the definition of the formal optimization problem of operating conditions for the equipment of thermal power plants using the criterion of minimum power losses and defines the methods of its solution. The main process parameters and external perturbations that influence the value of power losses in the direct flow boilers of thermal power stations have been defined. The mathematical model of the optimization problem of operating conditions for the equipment of thermal power plants using the criterion of minimum power losses has been constructed. The objective function, the vectors of input and output parameters, process limitations and the vector of external perturbation actions have been defined. The mathematical optimization model includes the basic parameters of steam, fuel, air, feed water and escaping gases and also the activating agents that make the combustion process more efficient. It has been shown that the task of the real-world problem of the optimization of operating conditions of the boiler using minimum power losses is to evaluate the parameters of controlled values at which energy losses in the boiler will be minimum (at a fixed value of the unit power) and construct the optimal statistical regulation curves of the boiler in the entire range of its normal operation. The offered optimization method of the operation of steam boilers of power plants allows for the reduction of energy losses in the boiler and for the improvement of technoeconomic indices of its operation.

Diagnostics of the power oil-filled transformer equipment of thermal power plants

Problems concerning improvement of the diagnostics efficiency of the electrical facilities and functioning of the generation and distribution systems through the examples of the power oil-filled transformers, as the responsible elements referring to the electrical part of thermal power plants (TPP), were considered. Research activity is based on the fuzzy logic system allowing working both with statistical and expert information presented in the form of knowledge accumulated during operation of the power oil-filled transformer facilities. The diagnostic algorithm for various types of transformers, with the use of the intellectual estimation model of its thermal state on the basis of the key diagnostic parameters and fuzzy inference hierarchy, was developed. Criteria for taking measures allowing preventing emergencies in the electric power systems were developed. The fuzzy hierarchical model for the state assessment of the power oil-filled transformers of 110 kV, possessing high degree of credibility and setting quite strict requirements to the limits of variables of the equipment diagnostic parameters, was developed. The most frequent defects of the transformer standard elements, related with the disturbance of the isolation properties and instrumentation operation, were revealed after model testing on the real object. Presented results may be used both for the express diagnostics of the transformers state without disconnection from the power line and for more detailed analysis of the defects causes on the basis of the advanced list of the diagnostic parameters; information on those parameters may be received only after complete or partial disconnection.

A Dynamic Risk Assessment Methodology for Maintenance Decision Support

The failure mode and effect analysis (FMEA) is a widely applied technique for prioritizing equipment failures in the maintenance decision‐making domain. Recent improvements on the FMEA have largely focussed on addressing the shortcomings of the conventional FMEA of which the risk priority number is incorporated as a measure for prioritizing failure modes. In this regard, considerable research effort has been directed towards addressing uncertainties associated with the risk priority number metrics, that is occurrence, severity and detection. Despite these improvements, assigning these metrics remains largely subjective and mostly relies on expert elicitations, more so in instances where empirical data are sparse. Moreover, the FMEA results remain static and are seldom updated with the availability of new failure information. In this paper, a dynamic risk assessment methodology is proposed and based on the hierarchical Bayes theory. In the methodology, posterior distribution functions are derived for risk metrics associated with equipment failure of which the posterior function combines both prior functions elicited from experts and observed evidences based on empirical data. Thereafter, the posterior functions are incorporated as input to a Monte Carlo simulation model from which the expected cost of failure is generated and failure modes prioritized on this basis. A decision scheme for selecting appropriate maintenance strategy is proposed, and its applicability is demonstrated in the case study of thermal power plant equipment failures. Copyright © 2016 John Wiley & Sons, Ltd.

IMPROVEMENT OF SYSTEMS OF TECHNICAL WATER SUPPLY WITH COOLING TOWERS FOR STEAM POWER PLANTS TECHNICAL AND ECONOMIC INDICATORS PERFECTION. Part 1

In order to reduce the temperature of cooling water and increase the efficiency of use of power resources the main directions of modernization of systems of technical water supply with cooling towers at steam power plants are presented. The problems of operation of irrigation systems and water distribution systems of cooling towers are reviewed. The design of heat and mass transfer devices, their shortcomings and the impact on the cooling ability of the cooling tower are also under analysis. The use of droplet heat and mass transfer device based on the lattice polypropylene virtually eliminates the shortcomings of the film and droplet-film heat and mass transfer devices of the cooling tower, increasing lifetime, and improving the reliability and efficiency of the operation of the main equipment of thermal power plants. The design of the water distribution devices of cooling towers is also considered. It is noted that the most effective are water-spattering low-pressure nozzles made of polypropylene that provides uniform dispersion of water and are of a high reliability and durability.