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Records with Subject: Process Operations
Showing records 26 to 50 of 696. [First] Page: 1 2 3 4 5 6 Last
Optimizing Thermal Efficiencies of Double-Pass Cross-Corrugated Solar Air Heaters on Various Configurations with External Recycling
Chii-Dong Ho, Hsuan Chang, Ching-Fang Hsiao, Yu-Chen Lin
April 21, 2023 (v1)
Keywords: collector thermal efficiency, cross-corrugated module, double-pass operation, external recycle, solar air collector
The effect of external-recycle operations on the thermal performance of double-pass cross-corrugated solar air heaters (SAH) under different operating conditions was investigated experimentally and theoretically. Additionally, the simultaneous ordinary equations were solved analytically for each proposed configuration. Four recycling types are introduced for improving the solar thermal performance with different external recycle processes, which are expected to enhance the heat transfer coefficient with a convective turbulent flow between the air and the absorber in the present study. Using recycling double-pass operations, two processes were conducted sequentially: air first flowed over the sinusoidal corrugated absorber plate and then flowed back later over the transverse sinusoidal corrugated bottom plate. Improved device performance was achieved due to the doubled heat transfer area over and under the corrugated absorber plate, from which both the sinusoidal cross-corrugated absorb... [more]
Investigating the Shielding Effect of Pulse Transformer Operation in Isolated Gate Drivers for SiC MOSFETs
Loreine Makki, Marc Anthony Mannah, Christophe Batard, Nicolas Ginot, Julien Weckbrodt
April 21, 2023 (v1)
Keywords: ANSYS Q3D Extractor, CM noise, gate-driver, planar transformer, shielding, SiC MOSFET, wide-bandgap
Wide-bandgap technology evolution compels the advancement of efficient pulse-width gate-driver devices. Integrated enhanced gate-driver planar transformers are a source of electromagnetic disturbances due to inter-winding capacitances, which serve as a route to common-mode (CM) currents. This paper will simulate, via ANSYS Q3D Extractor, the unforeseen parasitic effects of a pulse planar transformer integrated in a SiC MOSFET gate-driver card. Moreover, the pulse transformer will be ameliorated by adding distinctive shielding layers aiming to suppress CM noise effects and endure high dv/dt occurrences intending to validate experimental tests. The correlation between stray capacitance and dv/dt immunity results after shielding insertion will be reported.
Why Can Simple Operation and Maintenance (O&M) Practices in Large-Scale Grid-Connected PV Power Plants Play a Key Role in Improving Its Energy Output?
Hamid Iftikhar, Eduardo Sarquis, P. J. Costa Branco
April 21, 2023 (v1)
Keywords: operations and maintenance, photovoltaics, PV power plants, PV systems, solar energy
Existing megawatt-scale photovoltaic (PV) power plant producers must understand that simple and low-cost Operation and Maintenance (O&M) practices, even executed by their own personal and supported by a comparison of field data with simulated ones, play a key role in improving the energy outputs of the plant. Based on a currently operating 18 MW PV plant located in an under-developing South-Asia country, we show in this paper that comparing real field data collected with simulated results allows a central vision concerning plant underperformance and valuable indications about the most important predictive maintenances actions for the plant in analysis. Simulations using the globally recognized software PVSyst were first performed to attest to the overall power plant performance. Then, its energy output was predicted using existing ground weather data located at the power plant. Compared with the actual plant’s annual energy output, it was found that it was underperforming by −4.13%, le... [more]
Research on Temperature Monitoring Method of Cable on 10 kV Railway Power Transmission Lines Based on Distributed Temperature Sensor
Kai Chen, Yi Yue, Yuejin Tang
April 20, 2023 (v1)
Keywords: DTS, heating fault, on-line monitoring, power cable, railway power transmission lines, temperature
Railway power transmission lines (RPTL) are power lines that provide nontraction power supply for railways, such as communications and signals along the railway. With the advancement of technology, power cables are being used more and more widely. Operational experience has shown that during the operation of power cables, abnormal heat is often caused by fault factors such as poor joint crimping and severe partial discharge caused by insulation defects, leading to cable burns in extreme cases. Distributed temperature sensors (DTS), a kind of spatial continuous temperature sensor using sensing optical fiber, can measure the temperature along the cable and are expected to realize on-line monitoring and positioning of cable heating faults. This paper first builds a finite element model of the cable under various faults to calculate the distribution characteristics of the temperature field of the faulty cable. Then the results are verified through experiments with the external sensing fibe... [more]
Functional and Operational Requirements to Be Fulfilled by Conical Picks Regarding Their Wear Rate and Investment Costs
Krzysztof Krauze, Kamil Mucha, Tomasz Wydro, Edward Pieczora
April 20, 2023 (v1)
Keywords: conical picks, costs, longwall shearers, quality, roadheaders, underground mining
User’s choices of conical picks currently involve specifying their material and geometric parameters (functional requirements), incorporating the place and conditions of their work (operational requirements). The selection is usually made based on solely one criterion, which is the price. Thus, at the stage of both purchase and operation, the quality of picks, as well as their matching for a specific machine, are not assessed. The problem of defining whether the producer has fulfilled the user’s requirements arises only when the user questions the picks’ quality. Analysis of this problem has resulted in developing assumptions, concepts and research procedures based on the cutting process requirements. The procedure allows conducting tests to determine the geometric parameters of a pick, the type of material of the pick body and WC-Co insert, as well as the pick wear rate (intensity). The C2 index describes the wear rate (intensity)—the smaller its value, the slower the pick’s wear. Lab... [more]
Chemical Degradation of the La0.6Sr0.4Co0.2Fe0.8O3−δ/Ce0.8Sm0.2O2−δ Interface during Sintering and Cell Operation
Mélanie François, Maria Paola Carpanese, Olivier Heintz, Victoire Lescure, Davide Clematis, Lionel Combemale, Frédéric Demoisson, Gilles Caboche
April 20, 2023 (v1)
Keywords: cationic diffusion, impedance spectroscopy, interface, La0.6Sr0.4Co0.2Fe0.8O3−δ, Sm-doped ceria, X-ray photoelectron spectroscopy
A complete cell consisting of NiO-Ce0.8Sm0.2O3−δ//Ce0.8Sm0.2O3−δ//(La0.6Sr0.4)0.95Co0.2Fe0.8O3−δ elaborated by a co-tape casting and co-sintering process and tested in operating fuel cell conditions exhibited a strong degradation in performance over time. Study of the cathode−electrolyte interface after cell testing showed, on one hand, the diffusion of lanthanum from (La0.6Sr0.4)0.95Co0.2Fe0.8O3−δ into Sm-doped ceria leading to a La- and Sm-doped ceria phase. On the other hand, Ce and Sm diffused into the perovskite phase of the cathode. The grain boundaries appear to be the preferred pathways of the cation diffusion. Furthermore, a strontium enrichment was clearly observed both in the (La0.6Sr0.4)0.95Co0.2Fe0.8O3−δ layer and at the interface with electrolyte. X-ray photoelectron spectroscopy (XPS) indicates that this Sr-rich phase corresponded to SrCO3. These different phenomena led to a chemical degradation of materials and interfaces, explaining the decrease in electrochemical perf... [more]
The Importance of Optical Fibres for Internal Temperature Sensing in Lithium-ion Batteries during Operation
Markus S. Wahl, Lena Spitthoff, Harald I. Muri, Asanthi Jinasena, Odne S. Burheim, Jacob J. Lamb
April 20, 2023 (v1)
Keywords: fibre Bragg grating, lithium-ion batteries, optical fibre sensors, temperature measurement, thermal management
Lithium-ion batteries (LiBs) are widely used as energy storage systems (ESSs). The biggest challenge they face is retaining intrinsic health under all conditions, and understanding internal thermal behaviour is crucial to this. The key concern is the potentially large temperature differences at high charge/discharge rates. Excess heat created during charge/discharge will accelerate irreversible aging, eventually leading to failure. As a consequence, it is important to keep battery states within their safe operating range, which is determined by voltage, temperature, and current windows. Due to the chemically aggressive and electrically noisy environment, internal temperature measurement is difficult. As a result, non-invasive sensors must be physically stable, electromagnetic interference-resistant, and chemically inert. These characteristics are provided by fibre Bragg grating (FBG) sensors, which are also multiplexable. This review article discusses the thermal problems that arise du... [more]
An Analysis of Countries’ Bargaining Power Derived from the Natural Gas Transportation System Using a Cooperative Game Theory Model
Mihai Daniel Roman, Diana Mihaela Stanculescu
April 20, 2023 (v1)
Keywords: bargaining power, cooperative games, game theory, natural gas market, Nord Stream 2 pipeline, Shapley value
A large consumption of natural gas accompanied by reduced production capabilities makes Europe heavily dependent on imports from Russia. More than half of Russian gas is exported by transiting Ukraine, so in the context of the underlying conflict between the two, this is considered uncertain. Therefore, in this article, we modeled the natural gas transportation system using cooperative game theory in order to determine the bargaining power of the major players (Russia, Ukraine, Germany, and Norway) by using a form of the Shapley value. We described the interaction between countries as network games where utilities from transport routes are considered and proposed three scenarios where the gas flow from Russia to Ukraine is either diminished or completely interrupted, with the purpose of finding out how the bargaining power on this market is shifted in case of network redesign. In this context, we included in the analysis the scenario where the Nord Stream 2 pipeline will be finished. R... [more]
A Technology of Hydrocarbon Fluid Production Intensification by Productive Stratum Drainage Zone Reaming
Oleg Bazaluk, Orest Slabyi, Vasyl Vekeryk, Andrii Velychkovych, Liubomyr Ropyak, Vasyl Lozynskyi
April 20, 2023 (v1)
Keywords: completion of wells, innovative technology, intensification of production, nonlinear law, rock mass, well reamer
The paper proposes a new technology for fluid production intensification, in particular hydrocarbons, which is implemented via significant increasing of the local wellbore diameter in the interval, where the productive stratum is present. The proposed technology improves the well productivity by increasing the filtration surface area and opening new channels for filtering fluids into the well. The innovative, technical idea is to drill large diameter circular recesses in planes perpendicular to the well axis. After that, the rock mass located between the circular recesses are destroyed by applying static or dynamic axial loads. The required value of the axial force is provided by the weight of the standard drilling tool. As a result of the study, the analytical relations to specify the admissible radius of circular recesses and admissible thickness of rock mass between two adjacent circular recesses from the condition of safe operation are obtained. The numerical analysis carried out f... [more]
Overview of Solutions for the Low-Temperature Operation of Domestic Hot-Water Systems with a Circulation Loop
Theofanis Benakopoulos, William Vergo, Michele Tunzi, Robbe Salenbien, Svend Svendsen
April 20, 2023 (v1)
Keywords: circulation heat loss, domestic hot water systems, heat exchanger, low return temperature, micro-booster heat pump, storage tank
The operation of typical domestic hot water (DHW) systems with a storage tank and circulation loop, according to the regulations for hygiene and comfort, results in a significant heat demand at high operating temperatures that leads to high return temperatures to the district heating system. This article presents the potential for the low-temperature operation of new DHW solutions based on energy balance calculations and some tests in real buildings. The main results are three recommended solutions depending on combinations of the following three criteria: district heating supply temperature, relative circulation heat loss due to the use of hot water, and the existence of a low-temperature space heating system. The first solution, based on a heating power limitation in DHW tanks, with a safety functionality, may secure the required DHW temperature at all times, resulting in the limited heating power of the tank, extended reheating periods, and a DH return temperature of below 30 °C. Th... [more]
Thermal Imaging Study to Determine the Operational Condition of a Conveyor Belt Drive System Structure
Dawid Szurgacz, Sergey Zhironkin, Stefan Vöth, Jiří Pokorný, A.J.S. (Sam) Spearing, Michal Cehlár, Marta Stempniak, Leszek Sobik
April 20, 2023 (v1)
Keywords: belt conveyor, diagnostics, mechanical failure, preventative maintenance, thermal imaging, underground mining
The paper discusses the results of a study carried out to determine the thermal condition of a conveyor power unit using a thermal imaging camera. The tests covered conveyors in the main haulage system carrying coal from a longwall. The measurements were taken with a thermal imaging diagnostic method which measures infrared radiation emitted by an object. This technology provides a means of assessing the imminence and severity of a possible failure or damage. The method is a non-contact measuring technique and offers great advantages in an underground mine. The thermograms were analysed by comparing the temperature distribution. An analysis of the operating time of the conveyors was also carried out and the causes of the thermal condition were determined. The main purpose of the research was to detect changes in thermal state during the operation of a belt conveyor that could indicate failure and permit early maintenance and eliminate the chance of a fire. The article also discusses th... [more]
Analysis of Low-Power Boilers Work on Real Heat Loads: A Case of Poland
Bartosz Ciupek, Wojciech Judt, Karol Gołoś, Rafał Urbaniak
April 20, 2023 (v1)
Keywords: emission, harmful substances, low-power boiler, real heat load, solid fuel
The paper presents the methods of determination of the actual operation of solid fuel heating boilers in Poland. The analysis was based on an average annual distribution of the actual power outputs of the solid fuel heating boilers operated in four selected locations in Poland. Based on said data, three characteristic percent shares have been estimated of the nominal power outputs, at which the heating boilers in Poland operate throughout the year (divided into four characteristic portions—the seasons of the year). Additionally, for the analysis, the authors took into account the average annual temperature amplitude and the annual air quality information for the discussed locations and analyzed 30 solid fuel heating boilers in terms of their performance in the laboratory certification tests. In the final stage of the investigations, the authors initiated laboratory tests on the application of the combustion quality analyzers and their potential benefits.
Investigation of the Photon to Charge Conversion and Its Implication on Photovoltaic Cell Efficient Operation
Vasileios Kapsalis, Grigorios Kyriakopoulos, Miltiadis Zamparas, Athanasios Tolis
April 20, 2023 (v1)
Keywords: energy and light harvesting, irreversibility losses, nature-inspired mimicking, photovoltaic cell efficiency, quantum dynamics, thermal regulation
Efficient photon to charge (PTC) transfer is considered to be the cornerstone of technological improvements in the photovoltaic (PV) industry, while it constitutes the most common process in nature. This study aims to investigate the parameters that impact efficient PV-cell photon to charge conversion in two ways: (a) providing a brief research analysis to extract the key features which affect the electrical and optical performance of PV cells’ operation, and (b) investigating the dependance of these characteristics on the photon to charge mechanisms. The former direction focuses on the latest advances regarding the impacts of the microenvironment climate conditions on the PV module and its operational performance, while the latter examines the fundamental determinants of the cell’s efficient operation. The electrical and optical parameters of the bulk PV cells are influenced by both the external microenvironment and the intrinsic photon to charge conversion principles. Light and energ... [more]
Feasibility of Quasi-Square-Wave Zero-Voltage-Switching Bi-Directional DC/DC Converters with GaN HEMTs
Furkan Karakaya, Özgür Gülsuna, Ozan Keysan
April 20, 2023 (v1)
Keywords: Bi-directional DC/DC converter, gallium nitride, GaN HEMT, high-frequency operation, interleaving, power density, reliability
There are trade-offs for each power converter design which are mainly dictated by the switching component and passive component ratings. Recent power electronic devices such as Gallium Nitride (GaN) transistors can improve the application range of power converter topologies with lower conduction and switching losses. These new capabilities brought by the GaN High Electron Mobility Transistors (HEMTs) inevitably changes the feasible operation ranges of power converters. This paper investigates the feasibility of Buck and Boost based bi-directional DC/DC converter which utilizes Quasi-Square-Wave (QSW) Zero Voltage Switching (ZVS) on GaN HEMTs. The proposed converter applies a high-switching frequency at high output power to maximize the power density at the cost of high current ripple with high frequency of operation which requires a design strategy for the passive components. An inductor design methodology is performed to operate at 28 APP with a switching frequency of 450 kHz. In orde... [more]
Growth and Economic Performance of the Norwegian Wind Power Industry and Some Aspects of the Nordic Electricity Market
Johannes Idsø
April 19, 2023 (v1)
Keywords: LCOE, producer’s profit, the Nordic electricity market, wind power in Norway
Electricity has been produced in Norway in hydropower plants since 1877. The first wind power plant was put into operation in 1986. The growth in wind power production was weak in the first years after the turn of the millennium, but after Norway joined the Swedish subsidy scheme Tradable Green Certificates in 2012, there was significant growth in the wind power industry. While most of the hydropower production in Norway is owned by the public sector, the majority of wind power production is owned by foreign investors. Since wind power has been very much discussed in Norway, a levelized cost of energy (LCOE) model that can be well suited for this type of discussion is presented. The point here is that one must include all the costs, including the externalities. The Norwegian electricity market is dominated by a single player: Nord Pool. Ninety-six percent of all the electricity produced in Norway is sold through the power exchange Nord Pool, and the prices set by Nord Pool affect the f... [more]
Impedance Matching-Based Power Flow Analysis for UPQC in Three-Phase Four-Wire Systems
Xiaojun Zhao, Xiuhui Chai, Xiaoqiang Guo, Ahmad Waseem, Xiaohuan Wang, Chunjiang Zhang
April 19, 2023 (v1)
Keywords: impedance matching, impedance model, operation states, power flow, UPQC
Different from the extant power flow analysis methods, this paper discusses the power flows for the unified power quality conditioner (UPQC) in three-phase four-wire systems from the point of view of impedance matching. To this end, combined with the designed control strategies, the establishing method of the UPQC impedance model is presented, and on this basis, the UPQC system can be equivalent to an adjustable impedance model. After that, a concept of impedance matching is introduced into this impedance model to study the operation principle for the UPQC system, i.e., how the system changes its operation states and power flow under the grid voltage variations through discussing the matching relationships among node impedances. In this way, the nodes of the series and parallel converter are matched into two sets of impedances in opposite directions, which mean that one converter operates in rectifier state to draw the energy and the other one operates in inverter state to transmit the... [more]
Optimisation of Operation of Adsorption Chiller with Desalination Function
Karol Sztekler
April 19, 2023 (v1)
Keywords: Adsorption, chiller, desalination
The demand for electricity is growing rapidly along with economic development and increasing population. At present, its production is mainly based on non-renewable sources, which has negative impacts on the environment and contributes to global warming. A large proportion of the produced electricity is consumed by refrigeration equipment. Climate change and the progress of civilisation are additionally increasing the demand for cooling, with increasing electricity consumption as a consequence. One of the options for obtaining eco-friendly cooling is the use of adsorption chillers. These devices are powered by low-temperature heat and their operation only requires a small amount of electrical energy. The source of low-temperature heat can be, e.g., waste heat generated in many industrial processes. Its use allows one to increase energy efficiency and achieve additional financial benefits. However, adsorption chillers are characterised by low coefficients of performance. This paper pres... [more]
Enhancing Cybersecurity in Smart Grids: False Data Injection and Its Mitigation
Derya Betul Unsal, Taha Selim Ustun, S. M. Suhail Hussain, Ahmet Onen
April 19, 2023 (v1)
Keywords: cybersecurity attacks, cybersecurity for scada systems, false data injection, intruder detection, power system operation, power system protection, smart grid cybersecurity
Integration of information technologies with power systems has unlocked unprecedented opportunities in optimization and control fields. Increased data collection and monitoring enable control systems to have a better understanding of the pseudo-real-time condition of power systems. In this fashion, more accurate and effective decisions can be made. This is the key towards mitigating negative impacts of novel technologies such as renewables and electric vehicles and increasing their share in the overall generation portfolio. However, such extensive information exchange has created cybersecurity vulnerabilities in power systems that were not encountered before. It is imperative that these vulnerabilities are understood well, and proper mitigation techniques are implemented. This paper presents an extensive study of cybersecurity concerns in Smart grids in line with latest developments. Relevant standardization and mitigation efforts are discussed in detail and then the classification of... [more]
Novel Five-Level ANPC Bidirectional Converter for Power Quality Enhancement during G2V/V2G Operation of Cascaded EV Charger
Jorge Lara, Lesedi Masisi, Concepcion Hernandez, Marco A. Arjona, Ambrish Chandra
April 19, 2023 (v1)
Keywords: ANPC topology, DC-link split capacitors voltage balancing, electric vehicle charger, G2V/V2G operation modes, power quality enhancement, single-phase five-level converter
This paper presents a novel single-phase (SP) active-neutral point clamped (ANPC) five-level bidirectional converter (FLBC) for enhancing the power quality (PQ) during the grid-to-vehicle (G2V) and vehicle-to-grid (V2G) operation of an electric vehicle (EV) charger connected in series. This EV charger is based on a dual-active half-bridge DC-DC converter (DAHBC) with a high frequency isolation transformer. Unlike the comparable ANPC topologies found in literature, the proposed one has two more switches, i.e., ten instead of eight. However, with the addition of these components, the proposed multilevel converter not only becomes capable of properly balancing the voltage of the DC-link split capacitors under various step-changing conditions but it achieves a better efficiency, a lower stress of the switching devices and a more even distribution of the power losses. The resulting grid-tied ANPC-SPFLBC and DAHBC are accurately controlled with a cascaded control strategy and a single-phase... [more]
Hybrid DC-DC Converter with Low Switching Loss, Low Primary Current and Wide Voltage Operation
Bor-Ren Lin, Yi-Kuan Lin
April 19, 2023 (v1)
Keywords: circulating current, phase-shift PWM converter, resonant converter, ZVS
A full-bridge converter with an additional resonant circuit and variable secondary turns is presented and achieved to have soft-switching operation on active devices, wide voltage input operation and low freewheeling current loss. The resonant tank is linked to the lagging-leg of the full bridge pulse-width modulation converter to realize zero-voltage switching (ZVS) characteristic on the power switches. Therefore, the wide ZVS operation can be accomplished in the presented circuit over the whole input voltage range and output load. To overcome the wide voltage variation on renewable energy applications such as DC wind power and solar power conversion, two winding sets are used on the output-side of the proposed converter to obtain the different voltage gains. Therefore, the wide voltage input from 90 to 450 V (Vin,max = 5Vin,min) is implemented in the presented circuit. To further improve the freewheeling current loss issue in the conventional phase-shift pulse-width modulation conver... [more]
Determination of the Selected Wells Operational Power with Borehole Heat Exchangers Operating in Real Conditions, Based on Experimental Tests
Joanna Piotrowska-Woroniak
April 19, 2023 (v1)
Keywords: BHE, borehole heat exchanger, extracted energy, ground thermal conductivity, ground-source heat pump, heat power of borehole, thermal performance
On the basis of experimental studies, the operational power of four borehole heat exchangers (BHE) under real conditions was determined. The research was carried out in 2018−2019. The theoretical power of the BHE was verified with its operating power. The amount of thermal energy absorbed from the ground by individual BHEs, the operating temperatures obtained at the inlet and outlet of the exchanger, the annual brine flow rate, and the average operating power of the tested wells in two heating seasons were compared and analyzed. Both in 2018 and 2019, none of the examined exchangers achieved an average unit capacity of a well. The aim of the work is to verify the specific ground thermal efficiency indicators adopted for the design of the lower heat source, determined using the computational method and the TRT test with data obtained on the basis of experimental tests. The differences between the results of the tests of the operating parameters of the analyzed BHEs were shown. The data... [more]
Method for Assessment of Operation of Analog Filters Installed in the Measuring Lines for Electrical Quantities of a Mining Machine’s Converter Power Supply System
Jarosław Joostberens, Arkadiusz Pawlikowski, Dariusz Prostański, Krzysztof Nieśpiałowski
April 19, 2023 (v1)
Keywords: analog filter, frequency characteristics, induction motor, inverter, roadheader
A method for assessing the operation of analog filters installed in the measuring paths of current and voltage converters in the power supply system of a mining machine motor, using the example of the driving unit of a roadheader’s cutterhead, is presented. The suggested method is based on the identification of the fundamental harmonic of signals from the current and voltage sensors observed at the input and output of the tested filters, respectively. The identified parameters of the fundamental harmonic of signals before and after the filter allow the determination of points of the filter frequency’s characteristics and their comparison with the reference values. In the suggested method of assessing the operation of analog filters, the new approach consists of checking the frequency characteristics on the basis of identification of the basic harmonics of the signal at the input and output of the tested filter (installed in the measuring line of the electrical quantity) using data acqu... [more]
A Method to Avoid Underestimated Risks in Seismic SUPSA and MUPSA for Nuclear Power Plants Caused by Partitioning Events
Woo Sik Jung
April 19, 2023 (v1)
Keywords: alternating operation system, partitioning events, probabilistic safety assessment (PSA), underestimation of core damage frequency (CDF)
Seismic probabilistic safety assessment (PSA) models for nuclear power plants (NPPs) have many non-rare events whose failure probabilities are proportional to the seismic ground acceleration. It has been widely accepted that minimal cut sets (MCSs) that are calculated from the seismic PSA fault tree should be converted into exact solutions, such as binary decision diagrams (BDDs), and that the accurate seismic core damage frequency (CDF) should be calculated from the exact solutions. If the seismic CDF is calculated directly from seismic MCSs, it is drastically overestimated. Seismic single-unit PSA (SUPSA) models have random failures of alternating operation systems that are combined with seismic failures of components and structures. Similarly, seismic multi-unit PSA (MUPSA) models have failures of NPPs that undergo alternating operations between full power and low power and shutdown (LPSD). Their failures for alternating operations are modeled using fraction or partitioning events i... [more]
Application of Multispectral Images from Unmanned Aerial Vehicles to Analyze Operations of a Wastewater Treatment Plant
Bartosz Szeląg, Szymon Sobura, Renata Stoińska
April 18, 2023 (v1)
Keywords: GNDVI (green normalised difference vegetation index), multispectral images, spectral analyses, unmanned aerial vehicle (UAV), wastewater treatment plant (WWTP)
The main task of a wastewater treatment plant (WWTP) is to reduce pollutants that adversely affect the receiving environment in which the effluent is discharged. The operation of a WWTP is a complex task due to the number of different processes that take place in its process facilities. In order to maintain the high efficiency of a WWTP, it is necessary to control the quality of the effluent at the outlet and monitor the processes taking place there. The main objective of the research presented in this study was to evaluate the possibility of using unmanned aerial vehicle (UAV) technology and multispectral images acquired with a Micasense Red-Edge MX camera to analyse the performance of an activated sludge bioreactor using the example of a municipal WWTP in Poland. Remote sensing analyses were carried out to check the relationships between the calculated spectral indices and the quality parameters in the bioreactor. The spectral indices assessed were the normalised difference vegetatio... [more]
Optimal Energy Management for Virtual Power Plant Considering Operation and Degradation Costs of Energy Storage System and Generators
Kanjanapon Borisoot, Rittichai Liemthong, Chitchai Srithapon, Rongrit Chatthaworn
April 18, 2023 (v1)
Keywords: degradation cost, Electric Vehicles Charging Station (EVCS), Energy Storage Systems (ESS), optimal energy management, solar PhotoVoltaics (PVs), Virtual Power Plant (VPP)
Even though generating electricity from Renewable Energy (RE) and electrification of transportation with Electric Vehicles (EVs) can reduce climate change impacts, uncertainties of the RE and charged demand of EVs are significant challenges for energy management in power systems. To deal with this problem, this paper proposes an optimal energy management method using the Virtual Power Plant (VPP) concept for the power system considering solar PhotoVoltaics (PVs) and Electric Vehicle Charging Stations (EVCS). The Differential Evolution (DE) algorithm is applied to manage energy in the power system to minimize the operation cost of generators and degradation costs in Energy Storage Systems (ESS) and generators. The effectiveness of the proposed approach is examined and tested on the IEEE 24 bus Reliability Test System (RTS 24) using the MATPOWER tool on the MATLAB program for calculating Optimal Power Flow (OPF). In this study, two situations before and after applying the proposed method... [more]
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