Articles (KEE)
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Item A New Method of Smart Control of Single-Phase Photovoltaic Inverters at Low Voltage for Voltage Control and Reactive Power Management(2024) Hrouda, Josef; Čerňan, Martin; Procházka, KarelThis paper introduces a newly designed reactive power control method for single-phase photovoltaic (PV) inverters. The control focuses on easy application and autonomous actions. The regulation is designed with regard to the effective network operation and the saving of reactive power with the functionality of voltage control and optimization of active losses. This paper proves the easy application of the newly proposed control design using the implementation of a control algorithm into a dynamic photovoltaic power plant (PVP) model and supply point with PSCAD software. The long-term benefit of this control is illustrated by the MATLAB/Simulink case study of a one-week simulation over the CIGRE LV European benchmark four-wire network using data from smart meters and measured PVP generation, which was provided by the Distribution System Operator (DSO). The case study showed the benefits of the newly designed regulation in terms of saving reactive energy supply from the upstream system by up to 64% (the regulation contributes to the self-sufficiency of the LV network in terms of reactive power), a positive effect on the reduction of active losses by up to 1.5% and a simultaneous improvement of the voltage profile at the nodes of the modelled network is also observed. The case study also reveals the risks of autonomous control of $Q = f(V)$ single phase inverter on the voltage unbalance depending on its definition.
Item Temperature detection from electrical signals of induction system(2025) Knedlík, Michal; Rot, DavidThis article focuses on the development of a new method for detecting the temperature of workpieces heated by induction heating based on the analysis of electrical signals in the circuit of the induction ystem. The text compares commonly used temperature measurement methods, highlighting their technological advantages and shortcomings. The research also included the development of a special frequency converter optimized for the needs of the proposed temperature detection method. The properties of the new method were experimentally verified on four different types of ferromagnetic steels commonly used in industrial applications. The experimental results confirm the functionality and potential of this method for accurate and efficient temperature detection based on the analysis of electrical signalsItem Simplified methodology of economic evaluation of household PV installations in Czech Republic using Monte Carlo method(2024) Vinš, Martin; Gangur, MikulášThis paper deals with the design of a suitable, transparent, and reasonably accurate methodology for the economic evaluation of household photovoltaic (PV) installations in the Czech Republic. The basis of economic evaluations of household photovoltaic installations is a time model of energy balance from which cash flows result. Therefore, a specific methodology of the energy balance calculation is proposed to increase accuracy, while at the same time, reasonably increasing the energy balance model complexity by using the Monte Carlo method (probability model). Following the detailed analysis of the affecting factors and the compilation of the methodology for the energy balance calculation, the main stochastic parameters were specified. These specified stochastic parameters are estimated by the Monte Carlo method in multiple scenarios. The presented methodology of the energy balance calculation is also used for direct calculation where the mean values of the same specified stochastic parameters (without assumption of their probability) serve as the reference values for one scenario. Pros and cons of the designed methodology are demonstrated in a case study of an existing household photovoltaic installation. The mean values of the output parameters from the Monte Carlo method scenarios are then calculated for subsequent results comparison of both methods and also with the real (measured) values of the case study installation. Then a cash flows for each year of the installation’s lifetime are stated, and the internal rate of return (IRR) as an economic evaluation criterion is calculated. The resultsshow that IRR differs between methods by about 2.5% which may be crucial in such long-term projects on the verge of profitability. The accuracy of the application of the Monte Carlo method to the output parameters is then discussed in the conclusion where some possible recommendations for further work and project evaluators are indicated as well.Item TEPLATOR – česká jaderná výtopna(2024) Mašata, David; Vilímová, EvaTEPLATOR je inovativní koncept české jaderné výtopny pro výrobu čisté tepelné energie pro dálkové vytápění a průmysl. Představuje perspektivní řešení současných problémů spojených s uhlíkovou stopou a bezpečností dodávek energetických surovin v Evropě. TEPLATOR je reaktor moderovaný a chlazený těžkou vodou, využívající palivové soubory komerčních tlakovodních reaktorů uloženév tlakových kanálech. Článek podrobně popisuje konstrukční a bezpečnostní prvky TEPLATORu, včetně jeho primárního a vloženého okruhu, bezpečnostních systémů a upcyklování již použitého jaderného paliva. Dále se zabývá licencováním a technologickými výzvami.spojenými s manipulací s palivem. V závěru je prezentován architektonický návrh technologie, který má za cíl popularizovat jadernouenergetiku a demonstrovat možnosti umístění jaderných zařízení v blízkosti obydlených oblastí.Item Nezbytné technické inovace distribuční soustavy pro omezení rizik souvisejících se změnou výrobního spektra elektrické energie(2023) Noháč, KarelTento příspěvek konference je rekapitulací různorodých dopadů na změny a nezbytná opatření v elektrizační soustavě (ES), především v její distribuční části, přičemž téma v mnohém navazuje na předchozí příspěvky autora ve starších ročnících konference.Item Hybrid steel–composite cross-arm for distribution power lines(Elsevier, 2023) Zemčík, Hana; Kroupa, Tomáš; Vaňková, Tereza; Zemčík, Robert; Pihera, Josef; Prosr, Pavel; Kadlec, Petr; Šroubová, Lenka; Müllerová, Eva; Martínek, Petr; Pavlica, Richard; Komárek, Josef; Friedl, Jan; Polanský, Radek
Item Design and Operation Optimization of a Nuclear Heat-Driven District Cooling System(Hindawi, 2023) Abushamah, Hussein Abdulkareem Sale; Burian, Ondřej; Škoda, RadekItem Implementation of Digital Twin for Increasing Efficiency of Renewable Energy Sources(MDPI, 2023) Bělík, Milan; Rubanenko, OlenaItem Fixed neutron absorbers for improved nuclear safety and better economics in nuclear fuel storage, transport and disposal(Korean Nuclear Society, 2023) Lovecký, Martin; Závorka, Jiří; Jiřičková, Jana; Ondráček, Z.; Škoda, RadekItem Characterisation of neutron field in large graphite insertion in special core of the LR-0 reactor(Elsevier, 2023) Peltan, Tomáš; Vilímová, Eva; Czakoj, Tomáš; Matěj, Zdeněk; Mravec, Filip; Cvachovec, František; Šimon, Jan; Juříček, Vlastimil; Košťál, MichalItem Experimental verification of new neutron absorbers concepts(Elsevier, 2023) Závorka, Jiří; Lovecký, Martin; Jiřičková, Jana; Škoda, RadekItem Determination PV Module Technical Condition(European Association for the Development of Renewable Energies, Environment and Power Quality (EA4EPQ), 2021) Bělík, Milan; Rubanenko, OlenaItem Optimisation of energy accumulation for renewable energy sources(European Association for the Development of Renewable Energies, Environment and Power Quality (EA4EPQ), 2021) Bělík, MilanItem Optimisation of passive solar systems seasonal operation in conditions of central Europe(European Association for the Development of Renewable Energies, Environment and Power Quality (EA4EPQ), 2022) Bělík, Milan; Rubanenko, OlenaItem Possible implementation of Ex-core measurement in TEPLATOR graphite reflector(American Society of Mechanical Engineers (ASME), 2022) Vilímová, Eva; Peltan, Tomáš; Jiřičková, JanaItem Economics of reusing spent nuclear fuel by Teplator for district heating applications(Wiley, 2022) Abushamah, Hussein Abdulkareem Sale; Mašata, David; Müller, Michael; Škoda, RadekItem The power load model for electric vehicle charging modelling and its utilisation for voltage level studies and cables ampacity in distribution grid(Jan-Evangelista-Purkyne-University, 2021) Síťař, Vladislav; Vysloužil, Tomáš; Raková, Lenka; Hruška, TomášItem Evaluation of long term degradation process of monocrystalline Si photovoltaic panels(European Association for the Development of Renewable Energies, Environment and Power Quality (EA4EPQ), 2020) Bělík, MilanItem Environmental impact and aging properties of natural and synthetic transformer oils under electrical stress conditions(Wiley, 2021) Kurzweil, Peter; Schell, Christian; Haller, Rainer; Trnka, Pavel; Hornak, JaroslavItem A novel approach for distributed generation expansion planning considering its added value compared with centralized generation expansion(Elsevier, 2021) Abushamah, Hussein Abdulkareem Sale; Haghifam, Mahmoudreza; Bolandi, T. Ghanizadeh
