Articles (RICE)

Permanent URI for this collection

http://hdl.handle.net/11025/30065

Browse

Showing 1 - 20 out of 344 results

Sensitivity analysis of digital twin model for energy community PV system
(2025) Bělík, Milan; Rubanenko, Olena
The current energy situation in Ukraine is researched, considering the analysis of damages from missile attacks during the war. One of the ways to improve Ukrainian energy security is defined as decentralization of energy resources comprised with digitalization, decarbonization, democratization and deregulation (5D) increasing flexibility of the sector. The objectives are to examine in detail the 5D strategy. Distributed renewable energy sources are defined within the frame of Energy Community (EC) which was developed to adapt to current shortages in Ukrainian centralized grid. The EC digitalization is based on Digital Twin (DT) concept targeting design, monitoring, operational modifications and developing recommendations for the stable and optimal operation of photovoltaic systems. Energy community development and optimization include technical, meteorological, social, financial and environmental factors. Criterion programming was chosen as an effective solution to complex optimization problems. Sensitivity theory application is the basis for simplifying and optimizing the process of EC management. A model energy community ‘shelter city’ was created. The article highlights the problem of PV modules biological corrosion and suggests ways to eliminate it. In cases when biological corrosion cannot be avoided, approaches reducing its harmful effects are proposed to help during the design stage of a PV plant.
Advanced magnetic diagnostic coils based on TPC technology for COMPASS-U and EU-DEMO
(2025) Turjanica, Pavel; Řeboun, Jan; Ďuran, Ivan; Entler, Slavomír; Viererbl, Ladislav; Šimonovský, Marek
Magnetic diagnostic coils based on Thick Printed Copper (TPC) technology for COMPASS-U and EU-DEMO fusion reactors are introduced in this paper. Special emphasis is placed on the aspects of design and technology qualification. Firstly, the results of the tests carried out to qualify the TPC technology for the Tokamak environment are presented. Dedicated test samples were designed and temperature cycling irradiation and adhesion tests including electrical parameters measurements were executed. The aim of the TPC coil design was to achieve a high effective sensor area (up to 0.25 m2) and small dimensions compared to conventional coils. The coils can be composed from materials as Cu and Al2O3, AlN, or spinel (Al2MgO4) which ensures compatibility with elevated temperatures (at least 500 degrees C) and intense neutron radiation. Two coil variants, 1st with low winding density and 2nd with high winding density are proposed. Advanced layout of high-density coil winding achieving high suppression factor of cross-field sensitivity is presented. In parallel, the winding layout is also optimized to reduce parasitic radiation and temperature gradient induced side effects. Preliminary results of irradiation tests and temperature cycling test of TPC low winding density coil are presented.
Data fusion of magnetic coils and Hall sensors using Kalman filtering
(2025) Ivánek, Matěj; Ďuran, Ivan; Entler, Slavomír; Torres, André; Pironti, Alfredo; Quercia, Antonio; Sládek, Petr; Šimonovský, Marek; Řeboun, Jan; Turjanica, Pavel
Considering the broad bandwidth of magnetic coils from lower frequencies up to 10 s – 100 s of kHz and the narrow bandwidth of the Hall sensors from DC to low frequencies of the order of 10 s of Hz, an algorithm based on the Kalman filter combining the signals from both types of sensors to accurately estimate the measured magnetic field in tokamak plasma discharges is proposed. The data fusion algorithm utilizing the Kalman filter is described mathematically and validated using experimental data.
Temperature Tests of Miniature Ceramic/Antimony Hall Sensors for ITER and DEMO
(2024) Entler, Slavomír; Ďuran, Ivan; Sládek, Petr; Šimonovský, Marek; Řeboun, Jan; Turjanica, Pavel; Výborný, Karel; Ritzinger, Philipp; Šobáň, Zbyněk
The magnetic diagnostics of the ITER and DEMO reactors include Hall sensors to measure the steady-state magnetic field. High temperature compatible and neutron radiation-resistant Hall sensors based on an antimony-sensitive layer are being developed for this purpose. The tests confirm the linear dependence of the output Hall voltage of the sensors on the magnetic field and the stability of the sensors' sensitivity for temperatures up to 400 degrees C.
Tools for Researching the Parameters of Photovoltaic Modules
(2025) Bělík, Milan; Rubanenko, Oleksandr; Hunko, Iryna; Rubanenko, Olena; Baraban, Serhii; Semenov, Andriy
This paper addresses critical challenges in renewable energy research, particularly under the difficult operational conditions caused by the military conflict in Ukraine. Despite significant infrastructure loss due to the armed conflict (13% of solar and 70% of wind power), Ukraine maintains a commitment to reach 27% renewable energy in final consumption by 2030. However, the wartime conditions present unique challenges to scientific research, with laboratories vulnerable to missile strikes and frequently requiring evacuation. This paper introduces innovative portable laboratory stands designed for comprehensive analysis and monitoring of photovoltaic (PV) module parameters. These portable platforms, integrating advanced microcontrollers, sensors, and data-processing units, enable effective real-time monitoring and parameter estimation of PV modules, thereby enhancing their operational efficiency and reliability. Two distinct portable laboratory setups were developed and are detailed: the first focuses on real-time voltage and current measurements, while the second, termed the photovoltaic module parameter scanner (SPFEM), emphasizes data collection, remote data transmission, and database integration for subsequent analysis. This research provides essential tools for ensuring continuity in scientific activities and practical training for students and researchers amidst the ongoing security threats. The presented systems significantly contribute to optimizing the performance of PV systems in Ukraine and underscore the necessity for continuous adaptation and technological advancement in renewable energy infrastructure.
Verification of Maximum Torque Per Joule Loss Control of a Wound-Rotor Synchronous Machine with Strongly Non-Linear Parameters
(2025) Hruška, Karel; Glac, Antonín; Suchý, Ondřej
This paper presents an analytically derived optimal control strategy for wound-rotor synchronous machines (WRSM) based on minimising the Joule losses in both the stator and rotor windings. The presented control strategy is analysed in terms of analytical derivation, machine current ratios, working regions and constraints. It is experimentally verified on a salient-pole wound-rotor synchronous machine with strongly non-linear equivalent circuit parameters. The verification was performed in two stages: first, considering constant equivalent circuit parameters while assessing strong non-linear behaviour of the machine leading to significant discrepancies in the resulting machine torque. In the second stage, after determination of non-linear machine parameters using measured flux maps, identical control methodology is analysed in terms of variations in ratios between machine currents. Using pre-calculated current ratios the same control methodology is extended for machines with strongly non-linear equivalent circuit parameters and verified in a real environment. The measurement confirms expected machine behaviour in all available control regions achievable by used synchronous motor as well as limits between these control regions. The results of the verification in a real environment show a discrepancy of approximately 5% in measured machine torque in comparison to expected value confirming the validity of the analytically derived approach and introduced modifications for machines with non-linear equivalent circuit parameters.
Study of the neutron radiation hardness of MAPD-3NK2 silicon photomultipliers
(2025) Ahmadov, F.; Ahmadov, G.; Mammadli, A.; Sadygov, A.; Sadygov, Z.; Jazbec, A.; Ambrožič, K.; Holík, Michael; Akbarov, R.; Nuruyev, S.; Mamadov, F.; Okhrimenko, O.; Shitov, Yu.; Bacherikov, Yu.
The radiation hardness of MAPD-3NK2 photodiodes with deep-buried pixel structures was evaluated under neutron irradiation at fluences ranging from 3.6 × 109to 3.6 × 1012neq/cm². Irradiation induced dark current increase of up to 2060 times, a breakdown voltage shift of (0.37 ± 0.08) V, a photo signal amplitude reduction of (90.1 ± 0.4) %, and a tenfold degradation in amplitude resolution. Partial recovery was observed after 40 days of room-temperature annealing, with dark current decreasing by 35%.Similar performance changes were observed in photodiodes with artificially elevated dark current, indicating that excess current is the primary driver of degradation. This current likely impedes photoelectron detection by occupying pixels or failing to fully quench the avalanche process, thereby reducing photocurrent.
Development and testing of compact electronic modules for detectors based on SiPM array
(2025) Akbarov, Ramil; Nuruyev, Sabuhi; Tyutyunnikov, Sergei; Kučera, Patrik; Holík, Michael
Background: Compact electronic modules are essential for modern detector systems utilizing Silicon Photomultiplier (SiPM) arrays due to their small size, low power consumption, and high precision. To address the growing demand for portable and efficient detection systems, the development of modules tailored for such applications has become a critical focus. This study introduces compact electronic modules designed for detectors based on MAPD (Microcell Avalanche Photodiode) arrays, aiming to improve reliability and versatility for industrial, medical, and scientific applications. Methods: The developed modules include two primary components: DC-DC Voltage Converter: Based on the MAX1932ETC chip. Converts a 5 V input to a stable output voltage adjustable between 30 and 90 V. Supports a maximum current of 2.5 mA, ensuring reliable operation for SiPM arrays. Signal Amplification Unit: Utilizes the LTC6268 chip. Processes input signals ranging from 10 to 75 mV. Offers a gain factor of 45, characterized by low noise and high precision. The modules were integrated with a scintillation detector comprising a MAPD-3NM-II photodiode array and an LFs scintillator. Performance testing was conducted using a Cs-137 gamma source. Results: The energy resolution of the detector system was evaluated using the 662 keV gamma line from the Cs-137 source. The modules achieved an energy resolution of 10 ± 0.5%, demonstrating high reliability and efficiency. This performance confirms the modules’ capability to maintain stable operation and precise signal processing under real-world conditions. Conclusions: The developed compact electronic modules provide a cost-effective and efficient solution for detectors utilizing SiPM arrays. Their stable voltage conversion, low-noise signal amplification, and high energy resolution make them suitable for a wide range of applications in industrial, medical, and scientific fields. Future work may focus on optimizing the modules for broader voltage ranges and compatibility with different scintillator materials to expand their applicability.
Mozhlyvosti pidvyshchennia efektyvnosti roboty mikromerezh z systemamy na osnovi vidnovliuvanykh dzherel enerhii
(2025) Budko, V.; Korotchenko, D.; Bělík, Milan; Rubanenko, Olena; Budko, M.
Bilshist merezh ye zastarilymy yak fizychno, tak i shchodo metodiv keruvannia, yakymy vony operuiut. Vrakhovuiuchy znachne zbilshennia kilkosti kintsevykh korystuvachiv, a takozh enerhii, yaku vony spozhyvaiut, yikhnii vplyv na stiikist zahalnoi merezhi, stymuliuietsia rozvytok rozpodilenykh enerhetychnykh resursiv, a takozh intehratsiia novykh vuzliv heneratsii, shcho vykorystovuiut enerhiiu vidnovliuvanykh dzherel. Prote vstanovlennia takykh vuzliv zminiuie ustalenu systemu rozpodilu potuzhnostei ta spozhyvannia, a otzhe, vynykaie potreba v dynamichnomu keruvanni navantazhenniam ta heneratsiieiu. U tsii statti analizuiutsia rizni skhemy roboty mikromerezh, shcho ye okremymy nevelykymy vuzlamy zahalnoi enerhomerezhi, v yaki intehrovano stantsii, shcho vykorystovuiut vidnovliuvani dzherela enerhii, a takozh zastosovuvani metody vplyvu na pidtrymku yakosti elektropostachannia v merezhi. Perevahy ta nedoliky tsykh metodiv dozvoliaiut na praktytsi pryimaty obgruntovani rishennia shchodo pidvyshchennia efektyvnosti peredachi enerhii v mikromerezhakh z intehrovanymy ustanovkamy na osnovi VDE i v takyi sposib spryiaty vykorystanniu soniachnoi heneratsii dlia staloho vyrobnytstva enerhii. Rozghlianuto problematyku toho, shcho bilshist fotoelektrychnykh ustanovok, yaki buly vvedeni v poperedni roky, ye merezhozalezhnymy, shcho unemozhlyvliuie yikh proaktyvnyi vnesok u stabilizatsiiu merezhi v razi vynyknennia avariinoho rezhymu. Yak variant problema mozhe buty vyrishena za rakhunok invertornykh ustanovok, yaki formuiut napruhu, oskilky navit u razi vymknennia merezhi ta perekhodu mikromerezhi v avtonomnyi rezhym vony mozhut heneruvaty vlasnu napruhu i pidtrymuvaty elektrozabezpechennia usikh spozhyvachiv tsiiei pidmerezhi. U roboti navedeno rezultaty analizu naukovykh statei, prysviachenykh keruvanniu mikromerezhami ta heneruvalnymy ustanovkamy, a takozh zaproponovano metod keruvannia dekilkoma mikromerezhami dlia pidvyshchennia efektyvnosti roboty systemy rozpodilu. Sformulovani idei potrebuiut podalshoho doslidzhennia dlia poshuku efektyvnoho metodu keruvannia dekilkoma vuzlamy z riznymy heneruvalnymy ustanovkamy, dlia podalshoi implementatsii v realni systemy rozpodilu.
Exploiting facial side similarities to improve AI-driven sea turtle photo-identification systems
(2025) Adam, Lukáš; Papafitsoros, Kostas; Jean, Claire; Rees, Alan F.; Čermák, Vojtěch
Animal photo-identification (photo-ID), the process of identifying individual animals from images, has proven to be a valuable tool for various studies on sea turtles, increasing the knowledge of their ecology and informing conservation efforts. Photo-ID in sea turtles is predominantly based on the geometric patterns of the scales of their two head sides, which are unique to every individual and different from side to side. As such, both manual and automated photo-ID techniques are traditionally performed under a side-specific setting. There, an image showing a single profile of an unknown individual is compared only to images showing the same side of previously identified individuals. In this paper, we show for the first time an inherent visual similarity between left and right facial profiles of the same individuals in three sea turtle species. We do so by employing two state-of-the-art automated neural network-based photo-ID methods, one local feature-based and one deep embedding-based, designed to rank profiles based on their similarities. Both methods rank the similarity of the left and right profiles of the same individual higher than those of different individuals. These similarities are detectable even when images are taken years apart under diverse conditions. We further show that the exploitation of this similarity results in improved accuracies when compared to the traditional side-specific photo-ID setting. Our results indicate two concrete guidelines for improving automated sea turtle photo-ID workflows. When trying to match a photo of a given profile, searches should not be restricted only to photos of the same profile. As the first method of choice, a deep embedding model finely-trained using a photo-database of the focal sea turtle population should be used. In the absence of such training database, a neural network-based local feature method is preferable, but in that case searches should be performed with both the original query image and its horizontally flipped version.
Energy and profile of the proton beam of the IBA Cyclone 18/9
(2025) Zmeškal, Marek; Burian, Petr; Košťál, Michal; Czakoj, Tomáš; Peltan, Tomáš; Šimon, Jan; Broulím, Pavel; Růžička, Ondřej; Vadják, Šimon
The characteristics of the proton beam produced by the IBA Cyclone 18/9 medical cyclotron were investigated, focusing on its energy and profile. The proton beam energy was measured as 18.25±0.25 MeV using activation foil detectors. The beam profile was characterized using the Timepix3 based detector, revealing a Gaussian distribution with consistent widths and slight asymmetry in the horizontal plane. This study presents a straightforward methodology for evaluating cyclotron beam parameters using activation foils and pixel detectors, providing a tool for optimizing target design and expanding the applications of medical cyclotrons beyond radiopharmaceutical production.
Design Issues of Hybrid Energy Storage Systems of Electric Vehicles According to Driving Profiles
(2025) Frivaldsky, Michal; Danko, Matúš; Schönfelder, Tristan; Zavřel, Martin
This article examines the design challenges of hybrid energy storage systems (HESS) for electric vehicles (EVs), focusing on optimization based on driving profiles. Rising carbon dioxide emissions, especially in road traffic, require advanced energy solutions. In particular, electric vehicles offer great potential for reducing emissions in the transport sector. However, existing energy storage technologies such as lithium batteries have significant limitations in terms of power and energy density as well as cost efficiency, etc. To address these limitations, this study examines battery-SC hybrid systems, which represent a form of HESS. Using MATLAB Simulink, energy and power requirements are calculated for selected urban, combined, and motorway driving cycles. Based on the simulation results, which are obtained from mathematical vehicle dynamics models, this paper determines optimal configurations for battery and SC modules. Key findings highlight the trade-offs in performance, weight, and cost when designing HESS for varying vehicle classes. The study concludes that while HESS solutions significantly enhance energy efficiency and extend battery lifespan, their implementation remains complex and cost-intensive for medium and high-class vehicles. For lower-class vehicles, HESS offers an effective strategy to balance energy and power demands, contributing to sustainable transport solutions. The results provide important insights for the development of scalable and efficient hybrid storage systems that are designed for specific driving conditions.
Jaderné dny 2025
(2025) Ullmann, Jan; Mašata, David
Článek se věnuje konferenci Jaderné dny 2025, která představila komplexní odborný i popularizační program zaměřený na současné trendy v jaderné energetice v České republice. Konference na ZČU v Plzni se zaměřila na energetickou bezpečnost Evropy, rozvoj nových jaderných zdrojů a inovace v oblasti SMR. Součástí programu byly panelové diskuze, výstava současných technologií i mezinárodní studentská posterová sekce. Novinkou byly Dny firem, které propojily studenty s průmyslovou praxí. Akce posílila spolupráci akademické sféry, průmyslu a státních institucí a podpořila zájem mladé generace o jadernou energetiku.
Jaderné dny 2025: Jaderná energie a energetická bezpečnost Evropy
(2025) Ullmann, Jan; Mašata, David
Článek se věnuje konferenci Jaderné dny 2025, která představila komplexní odborný i popularizační program zaměřený na současné trendy v jaderné energetice v České republice. Konference na ZČU v Plzni se zaměřila na energetickou bezpečnost Evropy, rozvoj nových jaderných zdrojů a inovace v oblasti SMR. Součástí programu byly panelové diskuze, výstava současných technologií i mezinárodní studentská posterová sekce.Novinkou byly Dny firem, které propojily studenty s průmyslovou praxí. Akce posílila spolupráci akademické sféry, průmyslu a státních institucí a podpořila zájem mladé generace o jadernou energetiku.
Room temperature hydrogen sensor for the detection of flammable concentrations based on SWCNT modified by a solid solution of oxygen in Pd nanoparticles
(2025) Šorm, Martin; Štulík, Jiří; Křenek, Tomáš; Koštejn, Martin; Kupčík, Jaroslav; Hamáček, Aleš
Fabricating a high-response sensor for the repeatable detection of a high (flammable) hydrogen concentration (4 %) at room temperature with long-term stability remains a challenge. Here, a hydrogen (H2) sensor based on single-walled carbon nanotubes (SWCNTs) functionalized with palladium (Pd) nanoparticles of a previously unexplored structure is demonstrated. The active sensing layer is fabricated via airbrush deposition of SWCNTs and pulsed laser ablation of Pd in a vacuum. Complementary characterization techniques, including HRTEM, electron diffraction, STEM-EELS, Raman spectroscopy, and XP-spectroscopy, reveal that the Pd nanoparticles form a solid solution of oxygen in metallic Pd (Pd+O), partially covered with a two-dimensional palladium oxide (PdO) layer. The Pd+O/PdO nanoparticles exhibit an expanded face-centered cubic (FCC) and cubic primitive lattice, representing a previously unreported Pd structure. The sensor achieves a repeatable 203 % response to 4 % H2 at room temperature and operates over a wide concentration range (0.05 % – 10 % H2 in air) with long-term stability exceeding 1.5 years. The detection mechanism is hypothesized to involve ionosorption and/or oxygen vacancies in the PdO layer. These findings highlight the undiscovered potential of carbon nanostructure/Pd nanoparticle hybrids for enhanced hydrogen sensing through Pd structure tailoring.
Comparative analysis of printed electronics technologies in RF and microwave circuits
(2025) Lotfi, Saeedeh; Janda, Martin; Řeboun, Jan; Blecha, Tomáš
Printed electronics (PE) present a promising alternative to conventional photolithography by enabling rapid prototyping with reduced costs, material waste, and enhanced design flexibility and advantages, particularly relevant for high-frequency microwave applications. This study presents the design, fabrication, and evaluation of two microstrip low-pass filters (LPFs) with cutoff frequencies of 2.60 GHz and 3.55 GHz serving as representative components for microwave circuits, using three additive manufacturing techniques: Direct-Write (DW), Screen Printing (SP), and Aerosol Jet Printing (AJP). Over 60 filter samples were fabricated and measured to systematically assess performance across different printing methods. The LPFs were designed and analyzed through electromagnetic simulations, complemented by an LC equivalent circuit model based on actual device dimensions to better understand their behavior. Measured frequency responses showed strong agreement with simulations, validating the effectiveness of all three printing methods. Each technique demonstrated unique trade-offs between resolution, fabrication complexity, and electrical performance, emphasizing the need to tailor method selection to specific application requirements. This paper offers valuable insights into the design, analysis, and fabrication of RF and microwave circuits using printed electronics, highlighting the strengths and limitations of each technique. It serves as a practical guide for researchers in selecting suitable methods for high-frequency applications.
Open-source platform for simulation of physical fields: Agros
(2025) Karban, Pavel; Pánek, David; Kaska, Jan
Agros is an open-source software package designed to simulate and analyze physical fields, including electromagnetic, thermal, and mechanical phenomena. The software offers a versatile and intuitive graphical user interface (GUI) and supports multi-physics simulations, making it a valuable tool for academic research and industrial applications. This article provides an overview of agros development, focusing on recent updates that enhance its functionality, modularity, and usability. We discuss agros integration with the deal.II library and Python for advanced customization, which expands the capabilities of its core engine and postprocessor.
A Novel Discrete Resonant Control Method for Cascaded H-Bridge Rail Balancers
(2025) Straka, Miloš; Dragoun, Jaroslav; Talla, Jakub; Blahník, Vojtěch; Pittermann, Martin; Peroutka, Zdeněk
This paper presents the concept of an advanced rail balancer (ARB) for next-generation traction substations (TSSs), along with its control algorithm based on a novel advanced resonant controller. The ARB utilises a cascaded H-bridge (CHB) converter topology and is designed to effectively address several key issues in modern TSSs, including load current symmetrisation in the distribution power grid, reactive power compensation, harmonic currents from railway vehicles and active filtering of higher-order harmonics in the grid current. The proposed asymmetric control of the ARB converter includes individual ARB phase current control using an advanced resonant controller. The resonant controller algorithm provides the desired frequency response without offset and uses direct latency compensation to mitigate the effects of low switching frequency and large control sampling times. Experimental results show very good performance of the proposed control algorithm, especially for grid current harmonics filtration with low ARB switching frequency, large sampling times and control latency.
Modern training courses increasing awareness of environmental protection
(2025) Veg, Lukáš; Jeleń, Michal; Rassölkin, Anton; Stepien, Mariusz; Zygmanowski, Marcin
This paper addresses the increasing global emphasis on environmental protection across various sectors, particularly in education related to electrical engineering, electronics, mechatronics, and automation. It highlights the need for retraining individuals transitioning from the mining industry to high-tech sectors that focus on environmentally sustainable technologies. The paper discusses an international initiative under the Erasmus+ Strategic Partnership program to develop a platform for such retraining courses. Key project goals, outcomes, and the broader impact of this educational initiative on environmental awareness are also explored.
Maximizing Output Voltage of Three-Phase Nine-Leg Multilevel STATCOM by Minimum Infinity Norm Optimization
(2025) Adam, Lukáš; Komrska, Tomáš; Iška, František; Peroutka, Zdeněk
Power converters based on classic three-phase three-leg voltage source inverters (VSIs) that provide a multilevel output voltage are an interesting alternative to multilevel converters that suffer from complexity and higher costs. However, the multiple degrees of freedom of these systems pose a challenge to their optimal control. In this article, the minimum infinity norm algorithm is proposed and implemented for triple three-leg VSI static synchronous compensators (STATCOM) connected to a three-phase power grid. It is shown that the method provides optimal utilization of the dc-link voltage and allows to increase the output voltage by 39% compared to the minimum l2 norm method and by 16% compared to the phase-disposition pulse width modulation (PD-PWM) while keeping total harmonic distortion (THD) below 0.5%. In addition, the algorithm has been optimized for real-time systems, resulting in a very fast algorithm with a worst-case complexity of 39 scalar–scalar multiplications and no division.

Browse

Recent Submissions