1. Performance Enhancement of Grid Connected Multilevel Inverter Based Wind Energy Conversion System with LVRT Capability Using Optimized Type 2 ANFIS Based DVRCh. Sajan, P. Satish Kumar, Peter Virtič, 2024, izvirni znanstveni članek Opis: A Permanent Magnet Synchronous Generator (PMSG) based Wind Energy Conversion System (WECS) holds significant importance in the realm of Renewable Energy Sources (RES) for several reasons. The permanent magnets in the generator eliminate the need for a separate excitation system, leading to improved efficiency in power conversion. This makes PMSG-based WECS an effective and reliable source of wind energy electricity. The motivation behind the proposed conceptual framework stems from the need to overcome the limitations related to the integration of RES into the power grid, specifically focusing on voltage stability and Low Voltage Ride Through (LVRT) capability of PMSG based WECS. A Dynamic Voltage Restorer (DVR), empowered by an energy storage device, is used to mitigate voltage fluctuations and disturbances. The input DC voltage to the DVR is intricately regulated by a Type 2 Adaptive Neuro Fuzzy Inference System (ANFIS) Controller optimized using the Seagull algorithm, exhibiting intelligent adaptability to dynamic conditions. The rectified output from the WECS transforms an Isolated Flyback converter. Subsequently, a 31-Level Cascaded H-Bridge Multilevel Inverter (CHBMLI) along with a Proportional-Integral (PI) controller aids in generating high-quality AC output. By addressing challenges related to voltage stability and the ability to ride through low-voltage conditions, the proposed work contributes to enhanced grid stability. The use of advanced control techniques, including the Type 2 ANFIS Controller optimized by the Seagull algorithm, adds a layer of intelligent adaptability to changing environmental and grid conditions. A lower Total Harmonic Distortion (THD) Value of 1.29% is shown during the validation of the created system utilizing MATLAB/Simulink, assuring significant LVRT capabilities.
Ključne besede: Permanent Magnet Synchronous Generator (PMSG), Wind Energy Conversion System (WECS), Renewable Energy Sources (RES), Low Voltage Ride Through (LVRT), Type 2 Adaptive Neuro Fuzzy Inference System, 31-Level CHBMLI, Proportional-Integral (PI)
Objavljeno v DKUM: 06.11.2025; Ogledov: 0; Prenosov: 1
 Celotno besedilo (2,47 MB)
Gradivo ima več datotek! Več... |
2. Enhancing grid stability and low voltage ride through capability using type 2 fuzzy controlled dynamic voltage restorerCh. Sajan, P. Satish Kumar, Peter Virtič, 2024, izvirni znanstveni članek Opis: Introduction. The integration of Renewable Energy Sources (RESs), particularly Wind Energy Conversion Systems (WECS), is vital for reducing reliance on fossil fuels and addressing climate change. However, this transition poses challenges, including ensuring grid stability in the face of intermittent RESs. Compliance with grid codes is crucial, with a focus on Low Voltage Ride Through (LVRT) capability.
Problem. The intermittent nature of RESs, specifically in Permanent Magnet Synchronous Generator (PMSG) based WECS, presents challenges to grid stability during voltage dips.
Goal. To enhance voltage stability and LVRT capability in PMSG-based WECS by integrating a Dynamic Voltage Restorer (DVR) with an energy storage device. This involves regulating the input DC voltage to the DVR using a type 2 fuzzy controller, adapting intelligently to changing conditions.
Methodology. DVR, powered by an energy storage device, is strategically integrated with WECS. A type 2 fuzzy controller regulates the DC voltage to DVR. The rectified WECS output undergoes processing through an isolated flyback converter. A 31-level Cascaded H-Bridge Multilevel Inverter (CHBMLI) with PI control ensures high-quality AC output.
Results. The validation of developed system is executed using MATLAB/Simulink revealing a reduced Total Harmonic Distortion (THD) value of 1.8 %, ensuring significance in LVRT capability.
Originality. The strategic integration of DVR with PMSG-based WECS, addresses the LVRT challenges. The use of type 2 fuzzy controller for intelligent voltage regulation and a sophisticated multilevel inverter contributes to the uniqueness of proposed solution.
Practical value. The developed system provides benefits by ensuring reliable LVRT capability in PMSG-based WECS with reduced THD of 1.8 % indicating improved grid compatibility. References 26, tables 5, figures 20.
Ključne besede: permanent magnet synchronous generator, wind energy conversion systems, low voltage ride through, type 2 fuzzy controller, isolated flyback converter, 31-level cascaded H-bridge multilevel inverter, PI controller
Objavljeno v DKUM: 06.11.2025; Ogledov: 0; Prenosov: 2
Celotno besedilo (1,51 MB)
Gradivo ima več datotek! Več... |
3. Analysis of the Operational Reliability of Different Types of Switching Substations Using the Monte Carlo MethodFranjo Pranjić, Peter Virtič, 2024, izvirni znanstveni članek Opis: This study investigates the operational reliability of different types of switching substations within the context of power systems, employing the Monte Carlo method for analysis. The research focuses on evaluating the reliability of high-voltage substations, including single-busbar systems, double-busbar systems, and switchgears with a ring-type power supply. By conducting simulations and analyzing statistical data on device reliability, the study aims to identify the most reliable implementation of switching substations. The results are presented through graphical representations and comparative tables, highlighting the impact of factors such as the number of switching elements and their connection on operational reliability. The findings indicate that configurations with a greater number of busbars and a parallel connection of switching elements exhibit higher operational reliability. The study provides insights to inform decision-making in the construction of new switching substations, emphasizing the importance of stable operation within power systems.
Ključne besede: switchgear, switching devices, high voltage, operating reliability, unavailability, failure interval
Objavljeno v DKUM: 06.11.2025; Ogledov: 0; Prenosov: 2
Celotno besedilo (8,69 MB)
Gradivo ima več datotek! Več... |
4. Cogging torque reduction techniques in axial flux permanent magnet machines : a reviewFranjo Pranjić, Peter Virtič, 2024, pregledni znanstveni članek Opis: Axial flux permanent magnet machines have garnered significant attention in recent years due to their numerous advantages in various applications, including electric vehicles, wind turbines, and robotics. However, one of the critical challenges associated with these machines is the presence of cogging torque, which can hinder their efficiency and performance. This review article provides a comprehensive overview of the state-of-the-art techniques employed for cogging torque reduction in Axial Flux Permanent Magnet Machines. Different techniques are described, encompassing geometric optimization, magnet placement, and skewing methods. Firstly, the significance of Axial Flux Permanent Magnet Machines is described, as well as the issue of the cogging torque. In the methods section, a review of the strategies for the reduction of cogging torque is described from various articles, and finally, in the discussion section, a list of actions is presented for cogging torque reduction for different topologies. The novelty of the study is that it combines strategies for cogging torque reduction in a single article.
Ključne besede: cogging torque, axial flux permanent magnet machines, geometric optimization, magnet placement strategies, skewing techniques
Objavljeno v DKUM: 06.11.2025; Ogledov: 0; Prenosov: 2
Celotno besedilo (6,51 MB)
Gradivo ima več datotek! Več... |
5. Pregled prevzema in oddaje električne energije v elektroenergetskem sistemu Slovenije od leta 2019 do leta 2023Luka Gruden, 2025, magistrsko delo Opis: Namen magistrskega dela je predstaviti analizo pregleda prevzema in oddaje električne energije v elektroenergetskem sistemu Slovenije od leta 2019 do leta 2023. Na začetku smo na kratko predstavili elektroenergetski sistem Slovenije, glavne proizvajalce, njihove proizvodne zmogljivosti ter investicijske načrte posameznih proizvajalcev. V glavnem delu smo podrobno analizirali proizvodnjo in porabo električne energije v elektroenergetskem sistemu Slovenije med letoma 2019 in 2023 ter trende proizvodnje in porabe. Prikazali smo porast vključevanja in proizvodnje električne energije iz obnovljivih virov ter doseganje ciljev na osnovi nacionalnega energetskega in podnebnega načrta NEPN. Predstavili smo tudi bilanco moči v opazovanih letih. V
zaključnem delu smo predstavili vpogled v prihodnost elektroenergetskega sistema Slovenije do leta 2050 ter cilje za povečanje kapacitet proizvodnih enot v okviru doseganja nacionalnih in evropskih ciljev na področju energetike in podnebja.
Ključne besede: elektroenergetski sistem Slovenije, prevzem in predaja električne energije, energetska samozadostnost, analiza, proizvodnja električne energije, fotovoltaična energija, poraba
Objavljeno v DKUM: 01.10.2025; Ogledov: 0; Prenosov: 14
Celotno besedilo (787,35 KB) |
6. Uporaba baterijskih hranilnikov električne energije za razbremenjevanje elektroenergetskega sistemaLuka Kavšek, 2025, magistrsko delo Opis: Prehod v brezogljično družbo spodbuja uporabo obnovljivih virov energije kot tudi uporabo električnih prevoznih sredstev. Z naraščanjem električnih porabnikov in neobvladljivih virov električne energije, se povečuje potreba po zagotavljanju stabilnosti omrežja in nemoteni dobavi električne energije. Ena od rešitev za zagotavljanje stabilnosti omrežja je uporaba baterijskih hranilnikov električne energije. Magistrsko delo se osredotoča na možnost uporabe baterijskih hranilnikov električne energije (BHEE) za zagotavljanje sistemskih storitev in za razbremenjevanje sistema. Z izvedeno analizo vprašalnika je ugotovljena povečana uporaba baterijskih hranilnikov za zagotavljanje sistemskih storitev v ENTSO-E omrežju. Študijska vključitev BHEE v elektroenergetski sistem je izvedena s programskim orodjem, s katerim so izvedene simulacije pretokov moči in dinamičnih simulacij, s katerim smo potrdili zmožnost BHEE za hitro sproščanje delovne moči za preprečitev izpadov in pomoči sistemskim operaterjem.
Ključne besede: BHEE, stabilnost elektroenergetskega sistema, sistemske storitve, simulacije
Objavljeno v DKUM: 01.10.2025; Ogledov: 0; Prenosov: 8
Celotno besedilo (2,21 MB) |
7. Consumer protection in the electricity market in the European Union and Slovenia : vulnerable customers and emergency supplyNina Sotošek, Peter Virtič, 2025, izvirni znanstveni članek Opis: The article examines consumer protection in the electricity market, focusing on vulnerable customers and the right to emergency supply. At EU level, it outlines the development from the energy legislative packages to Directive (EU) 2019/944, which strengthens consumer rights and requires Member States to define and protect vulnerable groups. In Slovenia, these issues are regulated by Article 33 of the Electricity Supply Act (ZOEE), implemented through the System Operating Instructions (SONDSEE) and the Energy Agency’s act on criteria for ensuring emergency supply. The article applies normative and comparative legal analysis, reviews the Energy Agency’s Annual Reports, and analyzes case law. The findings reveal a gap between regulation and practice, as only one request for emergency supply was approved in Slovenia, in 2019. It proposes clearer criteria, simpler procedures, and more effective consumer information, particularly for vulnerable groups, to ensure the right to emergency supply is realized in practice.
Ključne besede: consumer protection, vulnerable customers, emergency supply, electricity market, ZOEE, Directive (EU) 2019/944, energy poverty, Energy Agency
Objavljeno v DKUM: 01.10.2025; Ogledov: 0; Prenosov: 6
 Povezava na datoteko |
8. Analiza ekonomske izvedljivosti vodikovih energetskih sistemov v Sloveniji : magistrsko deloKarin Marin, 2025, magistrsko delo Opis: Slovenija kot članica Evropske unije se je zavezala k izpolnjevanju ciljev Pariškega sporazuma, katerega glavni cilj je doseči podnebno nevtralnost z ničelnimi neto emisijami toplogrednih plinov do leta 2050. Ključno vlogo pri doseganju teh ciljev imajo obnovljivi viri energije (OVE), kot so sončna, vetrna, vodna in geotermalna energija. Kljub temu pa spremenljivost OVE predstavlja izziv za elektroenergetsko omrežje. Ena izmed možnih rešitev so hranilniki energije, kot so baterijski sistemi in vodik. Vodik kot energetski nosilec omogoča proizvodnjo iz obnovljivih virov, njegovo shranjevanje in kasnejšo pretvorbo nazaj v električno energijo. Kljub potencialu vodik prinaša tudi številne izzive, med drugim nizke izkoristke in visoke stroške, če ni proizveden iz presežkov OVE. Za oceno izvedljivosti vodikovih sistemov je bila v tem delu izvedena ekonomska analiza vodikovega sistema.
Ključne besede: zeleni vodik, vodikove tehnologije, ekonomska analiza, trg z električno energijo
Objavljeno v DKUM: 06.06.2025; Ogledov: 0; Prenosov: 54
Celotno besedilo (3,68 MB) |
9. Izgradnja priključnega SN kablovoda med TP Bele Vode Štakne, tč. 249 in TP Smrekovec (nadomestna) : diplomsko deloZoran Oblak, 2025, diplomsko delo Opis: V današnjem času je javnost prepričana, da je električna energija nekaj samoumevnega, vendar pa je realnost povsem drugačna. Pri opravljanju svojega dela pri podjetju Elektro Celje d.d. smo ob nepredvidenih izpadih in izklopih ob vzdrževanju deležni kritik odjemalcev električne energije. Zato tudi odločitev, da se deli srednjenapetostnega daljnovoda, ki pretežno poteka po gozdni površini, pokablira.
Naloga obravnava rekonstrukcijo srednjenapetostnega omrežja med TP Bele Vode Štakne, tč. 249 in TP Smrekovec (nadomestna). Projekt zajema vključevanje nove nadomestne transformatorske postaje s pripadajočim nizkonapetostnim omrežjem in rekonstrukcijo dotrajanega prostozračnega srednjenapetostnega omrežja. Rekonstrukcija je bila izvedena s kabliranjem. V projektu je zajeta izvedba del, uporaba potrebnega materiala in predviden finančni okvir rekonstrukcije srednjenapetostnega omrežja ter vključitev nove nadomestne transformatorske postaje. Cilj diplomske naloge je predstavitev rekonstrukcije dela srednjenapetostnega omrežja DV Lokovica med TP Bele vode Štakne, tč. 249 in TP Smrekovec(nadomestna), ki se napaja iz RTP Velenje.
Ključne besede: srednje napetostno omrežje, rekonstrukcija, podzemno omrežje, elementi srednje napetostnega omrežja.
Objavljeno v DKUM: 09.05.2025; Ogledov: 0; Prenosov: 49
Celotno besedilo (3,76 MB) |
10. Posodobitev sistema lastne rabe v energetskih objektih napetosti 110 kV : magistrsko deloDenis Leskošek, 2025, magistrsko delo Opis: Lastna raba je ključnega pomena za zagotavljanje stabilnosti delovanja energetskega objekta. Vsak energetski objekt ima svoje specifične sisteme lastne rabe glede na vir napajanja.
Sistem lastne rabe mora biti načrtovan tako, da ne vpliva na nihanja v energetskem sistemu. Vira napajanja, tako glavni kot pomožni, morata biti načrtovana tako, da zagotavljata zanesljivo delovanje.
Ključne besede: sistem lastna raba, dizelski električni agregat, napetostni napajalni transformator, AKU-baterije.
Objavljeno v DKUM: 23.04.2025; Ogledov: 0; Prenosov: 36
Celotno besedilo (3,54 MB) |
