Power Plant Unit Research Articles

Sistem informasi kepegawaian untuk perusahaan pembangkit listrik menggunakan model Rapid Application Development

The employee information system is an important tool for companies to manage employee data to make it easier, safer and more accurate. PT PLN Nusantara Power UP PLTU Tanjung Awar-Awar is a power plant unit under PT PLN which has approximately 700 employees consisting of pure employees from PT PLN and outsourced employees. However, currently the Human Resources division does not have the means to manage existing personnel administration. This causes the data not to be captured digitally so the data search process takes a long time. In this research, a website-based personnel information system was developed to handle personnel master data. The software development method used is the RAD (Rapid Application Development) model. This method is expected to save time in development. The program functionality testing method uses blackbox testing, and USE questionnaires as user satisfaction tests. In testing this application, 6 respondents were used who were company administration staff. The results obtained were that an employee information system was produced with a functionality category suitable for acceptance. Usability testing obtained a result of 79.44%, namely the category suitable for use.

TENORM radiation protection patterns for the sustainable health of workers

Background: Coal production in Indonesia continues to increase to meet national energy needs and export demand. Solid waste from the coal combustion process is estimated to increase significantly. One of the hazardous mining wastes is TENORM, but some TENORM is classified as production goods with economic value. The problem in this research is that the volume of waste containing TENORM is quite large, and the disposal, use, and recycling of TENORM has the potential to cause contamination for workers at the steam power plant and the surrounding environment. Objective: The purpose of this research is to obtain a design model for the protection of the environment and workers against TENORM radioactive waste from coal ash through an analysis of the social and economic perceptions of steam power plant workers regarding TENORM radiation and the effectiveness of TENORM radiation protection education to workers. Methods: A mixed method with a quantitative approach was applied. Data were gathered through field observation utilizing a questionnaire instrument that asked workers working at Steam Power Plant Units 1 – 7 a series of written questions. Results: Prior to Counseling, most Suralaya Steam Power Plant workers had shallow social and economic perceptions of TENORM radiation, with 88 percent unaware of its effects. The majority also paid between 100,000 and 500,000 IDR monthly in medical expenses. All respondents agreed that TENORM radiation safety counseling for Suralaya Steam Power Plant workers was utterly compelling, with acceptance of TENORM and WTP estimates following Counseling being the most important aspect. Conclusion: There was a significant relationship between the WTP variable after Counseling and the variables acceptance of TENORM protection (0.730), TENORM knowledge (0.627) before and after Counseling (after Counseling), and acceptance of TENORM protection (0.648), according to the pattern of protection for the SEM model.

METHODOLOGY FOR MODELING THE SPREAD OF RADIOACTIVE SUBSTANCES IN CASE OF AN EMERGENCY RELEASE AT A NUCLEAR POWER PLANT

The methodology for modeling the propagation of accidental releases of radionuclides from a power unit of a nuclear power plant has been developed. The calculation method takes into account the most critical factors propagation cloud - wind direction and speed, the intensity of the release radionuclides change: semi-continuous release, long-term release, instantaneous release. Diffuse processes and the presence of interference in the form of buildings were also taken into account. To solve the modeling equation of the aerodynamic model, the velocity potential equation is solved. The use of this equation instead of the traditional Novier-Stokes equation makes it possible to rationalize the calculation process in terms of the speed obtaining simulated data. To build a numerical model, a rectangular difference grid is used. The velocity potential and the quantities values of volumetric activity are determined at the centers of difference cells. The value of the airflow velocity vector component is determined on the sides of the difference cells. A finite-difference splitting scheme is used for numerical integration of the equation convective-diffusion transfer radionuclides. A computer code was developed on the basis of the constructed numerical model, the programming language Fortran was used. The approach used makes it possible to reduce the time for obtaining one scenario of an accident development. The cloud propagation dynamics determining is carried out almost in real time. This allows you to quickly respond to changing situations and make adequate decisions.

Cyclic Oxidation Behavior of HVOF Thermally Sprayed WC Cermet Based on AISI 1045 Steel

Thermal spray coating technology High-Velocity Oxygen Fuel (HVOF) has become one of solution for metal protect and parts recondition that work in critical environments such as oxidative, erosive, and corrosive. One of the thermal spray coatings (TSC) application has been carried out to improve the oxidation resistance of the Induce Draft Fan (IDF) as a part on coal fired steam power plant unit. Cermet WC10Co4Cr and WC17Co are intended to sustain the AISI 1045 steel substrate against the oxidative environment. In this works, the cyclic oxidation at a temperature 500oC were conducted to reveal the oxidation resistance behavior of the coatings. Several mechanical tests are also presented including surface roughness of the coatings, coatings microhardness, and coatings adhesion. The coatings morphology was also characterized using SEM microscope, as well as X-ray diffraction (XRD) for phase analysis after the oxidation test.

Justification of the Prospects for Selecting the Main Electrical Equipment in the Generator Circuit of High-Power Nuclear Power Plant Units

Justification of the Prospects for Selecting the Main Electrical Equipment in the Generator Circuit of High-Power Nuclear Power Plant Units

Analytical and simulation model of fighter flight dynamics with a limiter for the permissible flight envelope when performing the split-S maneuver

The article substantiates the relevance to develop an analytical-simulation model of fighter flight dynamics with a limiter for the permissible flight envelope during the split-S maneuver. The structure of the analytical and simulation model of a fighter, consisting of a combination of a flight test bench, a model of fighter flight dynamics, a model of an astatic limiter for the permissible flight envelope and a model of pilot control actions based on the theory of fuzzy sets, is presented. The structure of the model of fighter flight dynamics with a limiter for the permissible flight envelope, consisting of a system of differential and algebraic equations, a model of an integrated control system, a geometry, mass and balance unit, a unit for calculating aerodynamic forces, a power plant unit, a bank of aerodynamic performance, a unit for calculating feedback on efforts from flight controls, is presented. The model differs from the known ones by the availability of the split-S simulation unit, which is designed for the split-S simulation and the multi-iteration split-S simulation with different initial conditions to determine the basic split-S parameters, the kinematic flight operation performance and to construct the split-S implementation area. The split-S simulation unit comprises the specified value functions, a pilot control actions model, a unit for processing simulation results, a unit for determining the basic split-S parameters, and a database of operating modes. The specified value functions determine the specified values of the kinematic aircraft movement parameters, which are used to implement control in various phase coordinates of the maneuver. The model makes it possible to obtain reliable values of the kinematic fighter movement parameters under the semi-natural simulation with the participation of the pilot and the simulation split-S maneuver modeling using the pilot control actions model.

The low-carbon economic operation strategy of virtual power plant under different electricity-gas-heat-carbon multi-market synergy scenarios

Studying the grid integration of renewable energy power generation is crucial for achieving the goal of carbon neutrality since it may have a significant influence on the secure and reliable functioning of the power system. In order to solve the problem of deviation impact caused by renewable energy fluctuations and the optimal scheduling of VPP (Virtual Power Plant), the study divides the internal aggregation unit of the virtual power plant into two parts to model. One part is the source equipment, including wind power generation equipment, gas turbine, gas boiler and waste heat boiler. And the other part is the generalized Energy storage, including electric vehicles, air conditioners and alternative response loads. Ultimately, a generalized energy storage-based virtual power plant operation optimization model is developed under multi-market coordination of electricity-gas-heat-carbon. According to the study’s findings, adding more power-to-gas technology boosts revenue in the carbon trading market by 25.24 percent. The energy market’s revenue is equal to that in the absence of a carbon trading market, and the income of the natural gas market increases by $ 32.96. The income of the carbon trading market is $ 181.51, and the final operating cost is reduced by $ 180.80, a drop of 7.81%. To sum up, the suggested approach may more effectively achieve the best distribution of different energy sources, increase the dependability of VPP operation, and make it more low-carbon.

The Discovery of Radiocesium-bearing Microparticles Directly Delivered to a Person in Tokyo as a Result of the Fukushima Daiichi Nuclear Disaster.

The plume from Fukushima Dai-ichi Nuclear Power Plant (FDNPP) Unit 2, which reached the Tokyo metropolitan area on 15 March 2011 immediately after the FDNPP disaster, contained insoluble radiocesium-bearing microparticles (CsMPs). This study aimed to reanalyze a mask worn during the disaster to determine the ratio of CsMPs to radiocesium that directly arrived in the Tokyo metropolitan area as a plume immediately after the disaster. CsMPs were isolated from the non-woven masks worn at the Hongo Campus of the University of Tokyo from 15-16 March 2011 that trapped radioactive material from the accident. Twenty-two CsMPs with diameters in the range of 1.9-3.6 μm were found in the mask worn outdoors by one person. The CsMP radioactive ratio to overall radiocesium content of the mask was 9.9%. The CsMPs were collected more efficiently by the mask than by a suspended particulate matter filter. A face mask might trap CsMPs in a plume more efficiently than a suspended particulate matter filter. Determining the amount of CsMPs led to a reassessment of the internal dose by CsMPs that were inhaled by the public immediately after the FDNPP accident.

Analisis Potensi Daya Pada Pembangkit Unit 7 PLTA Tes

Currently the need for electrical energy is increasing both for industrial and household needs, but until now a lot of electrical energy has been replaced by non-renewable resources (coal), which will run out if it continues to be used. Tes Hydroelectric Power Plant is one of the electrical energy generators that can be renewable. Among the several generating units in Tes Hydroelectric Power Plant, Tes’s hydroelectric power plant unit 7 is the most recent, having been inaugurated for the first time in 2014. The power potential that can be projected from this hydroelectric power plant unit 7 still needs to be looked at further. Therefore, this study aims to analyze the potential for electric power from the Tes’s hydroelectric power plant unit 7 from 01 July 2022 to 03 July 2022.
 In making observations about the analysis of the power potential at the Tes’s hydroelectric power plant unit 7, several methods are used. Such as observation of data for 3 days of operation from 01 July 2022 to 03 July 2022, literature study and several interview methods with field consultants. The value of the air discharge obtained from the use of air volume per day at the Tes’s hydroelectric power plant unit 7. On three days of observation, the Tes’s hydroelectric power plant unit 7 were able to produce the highest electrical energy on 03 July 2022, namely 100,722 kWh and the lowest was 99,808 kWh on 02 July 2022. In three days, the electric power that paid for the Tes’s hydroelectric power plant unit 7 reached 4173, 40 kW. The Tes’s hydroelectric power plant unit 7 can generate a daily net income of Rp. 105,689,588, - with a perkWh price of Rp. 1300, - and reduced by the basic cost of Rp. 244.81, -, from the sale of electrical energy.

Influence of surface condensers connection configuration on power plant unit performance

Influence of surface condensers connection configuration on power plant unit performance

Hydropower Unit State Evaluation Model Based on AHP and Gaussian Threshold Improved Fuzzy Comprehensive Evaluation

Because a single monitoring index cannot fully reflect the overall operating status of the hydropower unit, a comprehensive state evaluation model for hydropower units based on the analytic hierarchy process (AHP) and the Gaussian threshold improved fuzzy evaluation is proposed. First, the unit equipment was divided into a hierarchical system, and a three-tier structure system (target layer-project layer-index layer) of the unit was constructed, and the weight of each component in the system was determined by the comprehensive weighting method. Secondly, according to the characteristics of the normal distribution of the historical health data of the unit, the upper and lower limits of the index were determined based on the Gaussian threshold principle, the real-time monitoring index degradation degree was calculated according to the index limit, and the degradation degree was applied to the fuzzy evaluation model to obtain the fuzzy judgment matrix. The result of assessment was divided into four sections: good, qualified, vigilant, and abnormal. Finally, combined with the unit hierarchical structure system, the weighted calculation of the fuzzy judgment matrix of each indicator, the overall fuzzy judgment matrix of the upper-level indicators of the unit was obtained, and the operating status of the unit was judged according to the matrix. Taking a real power plant unit as an example, the model was verified, and compared with other evaluation methods, the effectiveness and advantages of the proposed method were verified. In addition, the method proposed in this paper effectively solved the problems of index weighting and index limit determination in the existing model of unit condition evaluation.

Optimal size selection of combined diesel generator/fuel cell/photovoltaic system components using a multi‐objective strategy and sea lion optimization algorithm

AbstractOne of the challenges of the production sector of the electricity industry at present is how to meet the needs of electricity consumption in the country by using and localizing new power plant units. The main purpose of the presented paper is to offer an optimum arrangement for a combined diesel generator/FC/PV system for an off‐grid supply of electricity in a community in Shache, China. A multi‐objective scheme of the combined system is suggested with consideration of the unpredictability in solar radiation, load, and operating reserve (OR). The multi‐objective optimization has been established to make the TNPC (total net present cost) and LPSP (probability of power supply loss) minimum. In this study, the decision variables are the number of diesel generators (DG), photovoltaic (PV) panels, fuel cells (FC), electrolyzers, and hydrogen tanks. To get more authentication, the impact of several criteria on the size issue has been analyzed. The incorporation of a hydrogen production system lowers the overall expense of the combined systems, according to the modeling results. Plus, the operational reserve has a greater effect on the Pareto front in comparison with solar energy and load uncertainty.

Power Plant Performance Analysis on Variations of Generator Loading at Ombilin Coal Fired Steam Power Plant Unit 1 (2x100 MW)

Abstract— Steam Power Plants are classified as thermal plants that convert chemical energy in fuel into electrical energy. In an effort to increase the effectiveness of the work of the plant, there needs to be proper planning for its operations, this is important because it directly affects the operational costs incurred by the plant. This journal aims to determine the effect of changes in load or variations in generator loading on power plant performance, both efficiency, heat rate and production costs of electricity generation and to identify the magnitude of the decline in the thermal performance of the generator, as well as determine the causes and parts of the plant whose performance level decreases compared to optimal conditions. The method used to calculate the efficiency and heat rate is the “Direct Method”, namely by directly comparing the input energy with the electrical output produced. The data used in this study is the “Power Plant Performance Test” data. The results of this study get the most optimal conditions when loading 93.39 MW Net with efficiency 34.693%, heat rate 2475,445 kcal/kWh and electricity production costs 413,297 Rp/kWh. The conclusion of this study is that plant performance is getting better at high loads. Keywords: Thermal efficiency, Heat Rate, Electricity Production Cost, and Steam Power Plant

Revealing the effect of changing the operating parameters of a double hydrostatic bearing on its characteristics

The object of research is hydrostatic processes in sliding bearings with several layers of lubricant. The task addressed was the influence of the structural and operational parameters of dual hydrostatic plain bearings on their static and dynamic characteristics. As a static characteristic, the bearing capacities of dual and conventional sleeve hydrostatic bearings were considered. When analyzing the dynamic characteristics, the amplitude-frequency characteristics were determined. They were obtained by calculation and as a result of experimental studies. When calculating the amplitude-frequency characteristics, the trajectory method was used. As external forces in the equations of motion of the rotor, hydrodynamic forces, the weight of the rotor, and its unbalance were considered. Experimental determination of the trajectories of the rotor was carried out on a special bench. It has been established that the bearing capacity of a double type bearing is approximately 1.75–1.85 times higher than the bearing capacity of a conventional sleeve bearing. The range of stable operation of the rotor on double-type bearings is approximately 1.4 times greater in comparison with the range of stable operation of the rotor on sleeve hydrostatic bearings. The vibration amplitudes in the resonance region for double bearings were approximately 1.5 times less than the rotor vibration amplitudes for sleeve bearings. The results make it possible to recommend dual-type hydrostatic bearings for rotor bearings of nuclear power plants, in powerful aircraft engines with a gearbox, various types of pumps, and other power plant units. The derived theoretical dependences make it possible to carry out practical calculation of hydrostatic bearings of a double type

FLORISTIC COMPOSITION AND STRUCTURE OF VEGETATION IN GUNUNG SALAK GEOTHERMAL POWER PLANT, WEST JAVA, INDONESIA

This research had been conducted in the forest area around the Gunung Sa-lak Geothermal Power Plant of PT. PLN Indonesia Power. Plant diversity data in the geothermal power plant area had yet to be fully available. This study aimed to analyze the composition and structure of vegetation in the conservation forest area around the Gunung Salak Geothermal Power Plant unit. This study used a quadrat plot with a purposive sampling method. We sampled 873 individuals from 56 families of 110 species, consisting of native and introduced species. Some introduced flora species that have the potential to become invasive include Calliandra houstoniana, Asystasia gangetica, Bellucia pentamera, Miconia crenata, Maesopsis eminii, and Solanum torvum. The families with the highest number of species at each growth level were Fagaceae (tree), Fagaceae (pole), Arecaceae and Moraceae (sapling), also Acanthaceae, Arecaceae, Melastomataceae, and Poaceae in the understory. Several species of plant at the site are listed as Endangered (EN) based on the IUCN Red List, including Alpinia scabra, Castanopsis argentea, and Dipterocarpus hasseltii. These endangered plants are expected to become priority for conservation strategies and action plans. The Important Value Index (IVI) analysis shows different values at each growth stage. The highest IVI at the seedling and herb was Selaginella plana (29.74), the sapling was Macaranga triloba (20.59), the pole was Ficus fistulosa (43.27), and the tree was Schima wallichii (54.90). The value of the Shannon-Wiener (H') diversity index was 3.784, which indicates that the level of diversity is high.

Microstructure characteristics in weld zone of the novel thick 08Cr9W3Co3VNbCuBN heat-resistant steel welded joint by fusion welding

ABSTRACTOne of the primary candidate materials used in 650°C ultra-supercritical (USC) thermal power plant units is a novel thick grade of heat-resistant steel, 08Cr9W3Co3VNbCuBN (G115), for which China has complete intellectual property rights. In this study, G115 steel with a 115 mm thick wall was successfully welded using gas tungsten arc welding (GTAW) + shielded metal arc welding (SWAM), which was a significant step toward achieving its application in large-diameter boiler tubes. The influence of the welding process on the microstructure and mechanical properties of the G115 welded joint after post-weld heat treatment (PWHT) at 770°C for 11 h was investigated. The findings demonstrate that the weld zone (WZ) after PWHT was composed of martensite and ferrite, and M23C6 was the precipitate. The average hardness of WZ was 273.1 HV, and the average impact toughness was above 39J, which was sufficient for actual production applications. It offered the necessary theoretical foundation for the practical development of thick-walled G115 heat-resistant alloy steel during welding.

Recommendations on Selecting the NPP Generator Transformer VA Rating

The specific features of selecting the VA rating of a nuclear power unit step-up transformer are analyzed. The analysis is based on the provisions of the international standard IEEE C57.116-2022, which is a guide for transformers connected to turbine generators, taking into account the definition of the term “transformer VA rating” according to Russian and European standards (GOST 16110-82 and GOST 30830-2002). The definition of this term in this guide differs from that adopted in Russia and the EU member states. An example of analytical calculation of the generator step-up transformer steady-state apparent power in the reactive power generation and absorption modes (turbine generator inductive and capacitive operation modes) is considered. The calculation is confirmed by the simulation results in the ETAR software package. The inexpediency of selecting the generator step-up transformer VA rating from the standardized range of rated capacities according to GOST 17544-85 and GOST 9680-77 is substantiated. An adverse effect of overestimating the transformer VA rating on the maximum three-phase short-circuit fault current in the generator voltage circuit (in the main electrical connection circuit section between the turbine generator and step-up transformer) of a nuclear power plant unit is shown.

Algal extracts – The appropriate stabilizers for radiation processed UHMWPE

The present paper presents the stabilization effects of commercially available algal extracts of Chlorella vulgaris, Spirulina platensis and Ascophyllum nodosum added in UHMWPE matrices at the concentration of 2 wt%. The chemiluminescence assay reveals the high efficiency of active antioxidant components in γ-radiated materials after their exposure at 25 and 100 kGy in respect with pristine polymer. The main kinetic parameters depicting the progress of degradation, as well as the stabilization efficiency: onset oxidation temperature, oxidation induction time and oxidation rate are taken into consideration for the evaluation of protective activities. While the unirradiated neat ultra-high molecular weight polyethylene (UHMWPE) is degraded four times faster than the stabilized samples, all the modified polymer samples keep their exceptional oxidation resistance after the γ-exposure even at 100 kGy. The application of technological dose of 100 kGy maintains constantly oxidation endurance even at high operation temperature exceeding 200 °C. The extension of antioxidant features over the large dose range recommends the tested algal extracts safety usage compounds for the protection of various classes of polymer applied working in several conditions such as UV exposure during food handling, γ-sterilization, outdoor corrosion protection and insulation, sealing products for the security of fluid loops as functional units in nuclear power plants. The reported antioxidant evidences for the stability improvement of UHMWPE may be generally applied for all polymer formulations based on the oxidation protectors provided by nature.

Investigation of Kalina Cycle for Power Generation from Heat Dissipation of Tarasht Power Plant

Fuel consumption optimization in thermal power plants is one of the essential topics in the saving energy field in the world. Then; it is necessary to review and provide solutions to increase efficiency. The present manuscript has recovered the heat dissipation from power plant stacks. The Kalina cycle was studied to use exhaust gases to generate power in the Tarasht power plant. Net power output is calculated at about 2080 kW, which increases the total power production of the plant by about 5%. According to environmental analysis, this cycle will cause less damage to the environment due to lowering the temperature of the exhaust gases in the atmosphere and not using additional fossil fuels. Therefore; it is a good solution for using heat dissipation from power plants. The only thing to consider in this solution (based on economic analysis) is the high construction cost compared to other power plant units.

Carbon dioxide from oxy-fuel coal-fired power plant integrated green ammonia for urea synthesis: Process modeling, system analysis, and techno-economic evaluation

A high proportion of renewable energy integration will be one of the significant characteristics of future electric power grid, and power-to-NH3 technologies will become an important approach for inter-quarter long-term energy storage. Meanwhile, as an important method of peak regulation in power systems, coal-based power plant is necessary to implement CO2 capture. This study constructed a novel urea synthesis process based on renewable energy, including water electrolyzers, air separation, green ammonia, oxy-fuel combustion power plant, CO2 purification, and urea synthesis units. Coal- and natural gas-based urea synthesis processes were selected as the contrasting processes.The results showed that CO2 emissions from the novel process proposed in this work were 0.124–0.174 t CO2/t urea, which was much lower than that of the coal and natural gas-based urea processes (1.4 and 0.8 t CO2/t urea, respectively). In the current technical economy (with coal and natural gas prices of 450 CNY/t and 1.7 CNY/m3, respectively), the production cost of this new process was about 1.0–2.2 times higher than that of traditional processes. When the carbon tax values were 121 and 371 CNY/t, the total production costs of the natural gas- and coal-based urea process would exceed that of the new process, respectively. This study will provide a promising method for urea production based on renewable energy to realize CO2 utilization from coal-fired power plant.