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The energy transition is taking place in a diverse manner around the world, and the achievement of clean energy goals could follow very different pathways. However, two recent crises of Covid-19 and Ukraine hit all markets, especially the energy market, thus influencing strongly the energy transition in most countries including Southeast Asian countries. Southeast Asian countries are now playing a prominent role in the supply chain of clean energy sources, with good examples of different renewable energy growths in a very constrained environment of resources. One of these drivers is that the proper Feed-In Tariffs (FIT) mechanism has laid the foundation for the rapid development of renewable energy sources here and as a result, these countries are now standing on their own two feet. Vietnam is a prime example of such growth in solar PV deployment in recent years. Vietnam has become one of the leading countries in solar power in the world in recent years, especially after the Vietnamese government issued the appropriate FIT prices for grid-tied solar photovoltaic (PV) applications in 2019-2020. This has led to an explosion in the installed capacity of solar PV applications during the period of the issuance of these mechanisms in Vietnam. However, these FIT mechanisms seem to be still too simple, leading to the uneven development of these applications across the country. In some places such as Ninh Thuan and Binh Thuan provinces, transmission lines have experienced congestion due to a large number of solar power plants installed here, especially in Ninh Thuan province. In addition, the massive deployment of solar power into the distribution grids has also taken place in many places in Vietnam without being strictly controlled by competent parties. Faced with instability due to the loss of control of solar power in both transmission and distribution networks, the Government of Vietnam has had to find a series of solutions, and one of them is energy storage. Large-scale pumped hydro storage technologies have been considered for high-voltage transmission networks, while small-scale electrochemical storage technologies have been selected for distribution networks. However, the operational risks in static and dynamic security when simultaneously integrating both renewable power and storage systems in the same network need to be thoroughly investigated, especially in large networks. In addition, the use of this hybrid duo in isolated distribution networks in Vietnam is still facing many challenges because it is still very new here and the issues of reliability and vulnerability of these networks are not given the expected attention. For these reasons, this study was conducted to examine the impacts of solar power on transmission and distribution networks in Vietnam and to investigate the potential for integrating energy storage systems into these networks to ensure safety and security during their operation. The findings from this study suggest that choosing the right structure of the power mix could contribute to improving the operational security of isolated distribution networks, while the integration of a large-scale PHS system into the high-voltage transmission network in Ninh Thuan could contribute to solving congestion and supporting grid services in the face of the high penetration of solar power here. Moreover, several solutions to enhance the reliability of these grids are also proposed. The NEPLAN environment was chosen to simulate all scenarios under the Vietnamese grid code.

Es realitza un estudi teòric sobre què són les posades a terra i com són aquestes en els suports de les línies aèries d’alta tensió, analitzant els principals aspectes normatius que afecten a les instal·lacions presents a Espanya, Estats Units d’Amèrica, Regne Unit i Mèxic. Posteriorment, es duu a terme un estudi numèric per tal de confirmar diversos aspectes vists a la part teòrica. Aquest és realitzat mitjançant els softwares NEPLAN i MATLAB. En primer lloc, es fa una petita introducció als corrents de curtcircuit. Segonament, es crea un circuit elèctric a NEPLAN simulant una xarxa real per calcular corrents de curtcircuit monofàsic a terra. En tercer lloc, s’utilitza el complement AppDesigner de MATLAB per crear una aplicació de disseny de posades a terra per cadascuna de les normatives. Finalment, a cadascuna d’aquestes quatre aplicacions s’introdueixen els valors obtinguts amb NEPLAN, a part d’altres paràmetres característics com la resistència de posada a terra, la duració del defecte o la resistivitat del terreny, entre d’altres. Aquestes aplicacions tenen la finalitat de proveir un resultat conclusiu sobre si el disseny seleccionat és correcte respecte el criteri de seguretat de les persones dels diferents països. Finalment, s’elabora una anàlisi de com afecten els diversos paràmetres, com la resistivitat del terreny o el tractament del neutre, dels quals depèn principalment la instal·lació de posada a terra, del qual s’extreuen conclusions que, de certa manera, reafirmen tot el que es veu al llarg de l’estudi.

Potrebe za električnom energijom za napajanje potrošača industrijskih postrojenja najčešće se podmiruju iz distribucijske ili prijenosne mreže, a često ta postrojenja imaju i vlastitu energanu. Time je omogućen paralelni rad jednog ili više generatora s mrežom elektroprivrede - osigurana je veća pouzdanost napajanja, ali povećan je broj mogućih pogonskih stanja te se komplicira vođenje takvog sustava i podešenje njegove zaštite. Neispravan isklop u industrijskim postrojenjama često je ekonomski neprihvatljiv, te je pravilan odabir zaštite bitan za normalan rad takvog relativno kompliciranog sustava. Za pravilno podešenje zaštite prethodno se odrađuju proračuni kratkog spoja i praznog hoda, modeliraju se svi elementi i tereti u nekom od programskih paketa. Na temelju tih simulacija daju se prijedlozi osnovnih zaštita elemenata postrojenja. Electrical energy supply needs for industrial plant consumers are most often met from the distribution or transmission network, but usually, those plants have their own energy supply. This enables parallel operation of one or more generators with the public network - greater power reliability is ensured, but the number of possible operating states is increased which further complicates power system management and relay protection settings. Faulty switching in industrial plants is often economically unacceptable and correct relay protection selection is very important for the normal operation of such a complicated system. For correct protection settings, short circuit and load flow analysis must be conducted, along with element modelling in one of the available software packages. Based on these simulations, proposals for the basic protection of plant elements are given.

Udio niskougljičnih tehnologija i novih korisnika mreže je u konstantnom porastu. Iz tog razloga potrebno je imati alate koji će se koristiti za analizu strujno-naponskih prilika u mreži. Utjecaj novih korisnika na mrežu analiziran je korištenjem ETAP-a, NEPLAN-a i pandapower programske biblioteke.

U ovom radu cilj mi je bio obraditi problem proračuna struja kratkog spoja. Za početak sam ukratko objasnio simetrične komponente jer to smatram nužnim za razumijevanje ostatka rada. Nakon toga prešao sam na teoriju kratkog spoja, što je, čemu služi, koje su vrste, te koje sve struje su nam potrebne za dimenzioniranje zaštitnih i drugih uređaja. Kako bih se mogao pozabaviti samim proračunom struja kratkog spoja morao sam objasniti i normu IEC 60909. Ukratko sam objasnio pojmove distribucije i obnovljivih izvora energije jer je rad fokusiran na tom području. Prije kratkog primjera naveo sam i objasnio sve nadomjesne impedancije. Za kraj sam na primjeru jedne mreže matematički i pomoću programskog alata NEPLAN izvršio potpuni proračun struja kratkog spoja. Main goal in this paper was to explain the problem of short circuit current calculation. I started my paper with explanation of symmetrical components which I think is necessary to understand the rest of this paper. After that I began with theory of short circuit, what is that, what is it used for, what types are there and what currents we need protective and other devices sizing. To begin with calculation I had to explain very important norm which is norm IEC 60909. In few sentences I described electric power distribution and renewable energy sources. After all that theoretical explanations I did mathematical calculation of short circuit current. At the end of this paper I did calculation in program NEPLAN, same electrical network as used in example earlier.

Magistrska naloga prikazuje analizo kratkostičnih razmer industrijske cone UNIOR-ja v Zrečah pri različnih obratovalnih razmerah ter izdelavo rekonstrukcije transformatorske postaje TP UNIOR 1. V prvem delu je prikazana analiza kratkostičnih razmer industrijske cone v trenutnih in pri predvidenih obratovalnih razmerah. Opravljena je bila analiza kratkostičnih razmer za vsako obratovalno stanje na srednjenapetostnem in nizkonapetostnem nivoju v vseh šestih transformatorskih postajah, ki se uvrščajo v interno omrežje. Na osnovi izračuna kratkostičnih razmer s programskim orodjem NEPLAN in analitičnim izračunom je v drugem delu izdelan predlog rekonstrukcije transformatorske postaje TP UNIOR 1. Prikazan je način dimenzioniranja in izbire nove srednjenapetostne in nizkonapetostne opreme. Master thesis describes the analysis of short cicruit conditions of the UNIOR industrial network in Zreče at different operating conditions and the reconstruction of the transformer substation TP UNIOR 1. The first part present analysis of the short circuit conditions of the industrial zone in the current and anticipated operating condtions. An analysis of short circuit conditions was performed for each operating condition at medium voltage and low voltage level in all six transformer substations that are connected in the internal grid. Based on the calculated short circruit conditions with NEPLAN software tool and analytical calculations, the second part describes reconstruction of the transformer station TP UNIOR 1. The process of sizing and selecting new medium and low voltage equipment is shown.

The transient stability of the 12-bus Algerian southeast power system is studied in this paper. This electrical system has abundant reactive power due to the long transmission lines and generators’ voltage. This capacitive power increases bus voltage which leads to network instability. The use of conventional compensators does not provide adequate and fast solutions. FACTS technology improves the efficiency of these compensators in solving the problem of power system instability efficiently. Among its elements, a synchronous compensator STATCOM control is proposed to decrease bus overvoltage and damping oscillations. Disturbance at bus B-1 is taken into consideration. This disturbance represents the photovoltaic (PV) array which exploits the abundantly available solar irradiation in the desert of Algeria. Various simulation tests have been carried out using NEPLAN software and the proposed design algorithms are proved in the relevant discussion.

Diplomsko delo v uvodu podaja kratek opis problematike proizvodnje električne energije. V prvem poglavju opisuje smernice RS pri realizaciji proizvodnje električne energije iz obnovljivih virov. Nato je podrobno predstavljena oprema, potrebna za obratovanje malih hidroelektrarn. Sledi kratka predstavitev obravnavane male hidroelektrarne Ceršak s podrobno opisano zgodovino večjih objektov elektrarne. Nato sledi potek same prenove elektrarne, kjer se najprej na kratko podana zakonodaja, ki predpisuje cilje dosežene s prenovo. V istem poglavju je predstavljen tudi potek meritev energetskih karakteristik elektrarne in celoten potek prenove agregata 2. Zatem so predstavljeni še vsi preskusi, ki se izvedejo pred začetkom obratovanja na novo vgrajenega agregata. Na koncu sledi še izdelava simulacijskih modelov v programu NEPLAN in analiza obratovalnih razmer. The introductory part present a short description of problems occuring when generating power. The subsequent part describes guidelines of Slovenian power generation plan from renewable sources for the future. Next chapter provides description of all equipment and buildings used for generating electricity in small hydro powerplants. Then follows a brief description of small powerplant Ceršak and its history. Afterwards follows the main chapter where we find a short description of law and regulation regarding powerplant renovation and take a closer look of renovation itsel. Next chapter provides a full description of all required tests on all newly installed equipment before it's put in service. And finally there is a description of simulation model and analysis of operating conditions.

El modelo de movilidad eléctrica puede ser viable para transporte masivo y para transporte individual. Sin embargo, este modelo requiere infraestructura que garantice el suministro de energía eléctrica de la misma manera en que está para los Vehículos de Combustión Interna (ICE). Este documento presenta la evaluación del desempeño tecnológico de las Estaciones de Recargas Rápidas. La evaluación tecnológica incluye los siguientes escenarios: cuando la estación de recarga es alimentada por la red eléctrica, y cuando es soportada por generación renovable con sistemas de almacenamiento. La evaluación se realiza con el apoyo del NEPLAN que es una herramienta informática para analizar, planear, optimizar y simular redes eléctricas. Con el NEPLAN se simulan los diferentes escenarios en estado de falla y de funcionamiento normal. Este documento revisa la reglamentación estableciendo sus alcances, y realiza una comparación entre las normas internacionales y las nacionales. Abstract: The model of electric mobility can be for mass transit and personal transportation. However, it requires infrastructure to make sure the supply of electricity such as internal combustion engine (ICE). This document presents the evaluation of the technological performance of the Rapid Refueling Stations. The technological evaluation includes the following scenarios: when the recharging station is powered by the electrical network, and when it is supported by renewable generation with storage systems. The evaluation is carried out with the support of NEPLAN, which is a computer tool for analyzing, planning, optimizing and simulating electricity networks. With the NEPLAN, the different scenarios are simulated in the fault state and in the normal operation. This document reviews the regulations establishing their scope, and makes a comparison between international and national standards. Maestría

Ovaj diplomski rad se bavi problematikom priključenja velikog fotonaponskog izvora na distribucijsku mrežu. U uvodnim poglavljima je dan pregled današnje fotonaponske tehnologije te općeniti opis fotonaponskih sustav. Opisani su različiti modeli fotonaponskih sustava. Dalje je opisan i razrađen model distribucijske mreže te je opisan način priključenja fotonaponske na elektroenergetski sustav te su opisani parametri kvalitete električne energije koji moraju biti mjereni tijekom priključenja distributivnog fotonaponskog izvora. U glavnom dijelu rada je napravljen model elektroenergetskog sustava te je napravljena simulacija priključenja fotonaponskog distribucijskog izvora na elektroenergetski sustav. Utjecaj fotonaponskog sustava prikazan je kroz naponske prilike u mreži, tokove snaga i analizu harmonijskog izobličenja u mreži. This graduate thesis deals with the issue of connecting a large photovoltaic source to the distribution power grid. The introductory chapters provide an overview of today's photovoltaic technology and a general description of the photovoltaic system. Various models of photovoltaic systems are described. The model of the distribution power grid is described and elaborated further, and the method of connecting the photovoltaic to the power system is described including the electrical quality parameters that need to be measured during comissioning of the photovoltaic source. In the main part of the work a model of the power system was made as well as a simulation of the connection of the photovoltaic distribution source to the power system. The influence of the photovoltaic system is illustrated through network voltages, changes in power flow, and the analysis of the harmonic distortions in the power grid.

The reduction of the inertial response of the generation system has been one of the main obstacles to the penetration of high sharing of renewable energy sources in islanded systems. This issue can be solved thanks to innovative control that makes wind turbines able to provide the so-named synthetic inertia. The paper investigates some scenarios with different levels of wind power penetration in a small island whose grid is not supplied by the main grid, by the use of the software NEPLAN 360, simulating the wind power plants accordingly to the standard IEC 61400-27. The aim of the paper is to assess the maximum level of penetration in the island of wind generation, with traditional control systems, that does not threaten the stability of the system.

U ovom radu opisana je analiza integracije električne energije iz obnovljivih izvora u energetski sustav otoka Mljeta primjenom EnergyPLAN i NEPLAN alata za energetsko planiranje. Kako bi se odredio utjecaj obnovljivih izvora na energetski sustav otoka korišten je NEPLAN model te je dan opis samog programa i modula koje on koristi. S obzirom na to da su analize i mogućnosti korištenja obnovljivih izvora energije na otoku Mljetu opisane u nekoliko istraživačkih radova, ukratko su se opisali rezultati tih proračuna i korišteni model. S ciljem definiranja ulaznih podataka napravljena je analiza elektroenergetskog sustava otoka Mljeta i njegove potrošnje. U EnergyPLAN modelu proračunata je potrebna snaga fotonaponskih panela uz uvjet 5% „kritičnog viška proizvodnje električne energije“. U NEPLAN modelu je napravljen proračun tokova snage po čvorovima mreže te je snaga dobivena EnergyPLAN modelom unesena u NEPLAN model i raspoređena po distribucijskoj mreži otoka Mljeta. Napravljena je usporedba s proizvodnjom fotonaponskih elektrana i bez njih. Zaključak je dan na kraju, prije popisa literature. This thesis describes the analysis of the integration of electricity from renewable energy sources into energy system of the island of Mljet using EnergyPLAN and NEPLAN energy planning tools. To determine the impact of renewable energy sources on the energy system of the island NEPLAN model was used and at the beginning was NEPLAN and modules that he uses described. Since are the analysis and the possibility of using renewable energy sources on the island of Mljet described in several research papers, the results of those calculations and model which was used are briefly described. With the aim of defining the input data the analysis of the power system of the island of Mljet and its consumption were made. In Energy plan model it was calculated required output of photovoltaic panels providing the 5% of the critical excess electricity production. In NEPLAN model it was calculated load flow per network nodes and the power calculated in EnergyPLAN model was entered in NEPLAN model and deployed per the distribution network of the island. A comparison with the production by photovoltaic power plants and without them was made. The conclusion is given at the end, before references.

U teoretskom dijelu opisano je ponašanje međusobno povezanih sustava na modelu mreže s dva čvorišta i jednim vodom. Opisani su mehanizmi upravljanja tokovima snaga. Uveden je koncept FACTS (Flexible Alternate Current Transimission System) uređaja. Dan je pregled i osnovna podjela FACTS uređaja. Obrađene su pojedine kategorije FACTS uređaja s naglaskom na njihove međusobne razlike i funkcije. Opisan je i mehanizam upravljanja iznosom i kutom napona. Definirani su regulatori napona i kuta te je objašnjenja fundamentalna razlika u principu njihovog djelovanja. Opisan je utjecaj na tokove snage regulatora faze ili transformatora sa zakretom faze (PST - phase shifting transformer ili PAR - phase angle regulator). U praktičnom dijelu, demonstrirana je primjena određenih vrsta FACTS uređaja (TCSC, UPFC) i PST-a u upravljanju tokovima snaga na modelu mreže od četrdeset i osam čvorišta baziranom na standardnoj testnoj IEEE mreži od dvadeset i četiri čvorišta. U proračunu je korišten programski alat NEPLAN. In the theoretical part the behavior of an interconneced transmission system was described on a two node and one line network model. The mechanisms of power flow control were described as well. The concept of FACTS(Flexible Alternate Current Transimission System) devices was introduced. The overview and basic division of FACTS devices was given. Categories of FACTS devices with emphasis on their mutual differences and functions were describes. The mechanism of voltage magnitude and angle regulation was also givne. Phase angle and voltage regulators were defined and the basic difference in their operational principe was explained. The influence of the phase shifting transformer or phase angle regulator on the power flow was described. In practical sense, the use of certain types of FACTS devices (TCSC, UPFC), and phase- shifting transformer in power flow control was demonstrated on the standard IEEE 48 - nodes network model. NEPLAN programming tool was used in all calculations.

U ovom se radu u programskom alatu NEPLAN izradio simulacijski model cjelokupnog elektroenergetskog sustava tvornice stakla Vetropack Straže te dvije transformatorske stanice iz kojih se on napaja. Zadatak je ovog rada bio analizirati utjecaj pogona novog kompresora na elektroenergetsku mrežute tvornice. Najveći utjecaj na elektroenergetsku mrežu asinkroni motor ima prilikom svog zaleta, kada iz mreže uzima vrlo veliku poteznu struju pa su se stoga provodili proračuni tokova snaga i zaleta motora kod nekoliko najčešćih uklopnih stanja elektroenergetskog sustava. Nakon provedenih proračuna tokova snaga ustanovljena je potreba za kompenzacijom jalove snage u transformatorskoj stanici TS 6. Također, zbog smanjenja tereta na niskonaponskim sabirnicama te zbog ekonomske opravdanosti, predložen je rad samo dva transformatora u toj transformatorskoj stanici. Nadalje, ustanovljeno je da bi za napajanje TS 6 iz TS 35/10 bilo potrebno od HEP‐a (Hrvatska elektroprivreda d.d.) zatražiti uključenje oba transformatora u TS 35/10. U slučaju da se cjelokupni teret napaja preko TR1 u TS 110/35/10 postiže se značajno smanjenje gubitaka tronamotnih transformatora u TS 110/35/10, ali se zbog direktne povezanosti distribucijske i elektroenergetske mreže tvornice značajno narušava kvaliteta opskrbe električnom energijom elektroenergetskog sustava tvornice. Iz proračuna zaleta motora zaključeno je da potezna struja uzrokuje propade u svim transformatorskim stanicama. Međutim, u trenutku uklopa napon je na svim sabirnicama veći od 90 % nazivne vrijednosti čime je zadovoljena odredba o naponskim propadima unutar norme HRN EN 50160. U trenutku uklopa motora na mrežu, kod uklopnog stanja kada se cijeli elektroenergetski sustav tvornice napaja iz TS 35/10, potezna struja uzrokuje preopterećenje oba transformator u TS 35/10. Da bi se izbjegnulo preopterećenje tih transformatora, preporuča se obavljanje zaleta motora u osnovnom ili nekom drugom uklopnom stanju u kojem ne bi dolazilo do preopterećenja. Pomoću ovog će se simulacijskog modela moći provoditi svi potrebni proračuni u daljnjem širenju i nadogradnji elektroenergetskog sustava tvornice stakla Vetropack Straže.

Većina podataka o elementima distribucijske mreže i postrojenja pohranjena je u Geografskom informacijskom sustavu (GIS). Tehnički podaci o elementima mreže i podaci o njihovoj međusobnoj povezanosti postoje u GIS-u, a potrebni su kod proračuna i moraju se ponovno ručno unositi u aplikacije za proračune. Dolazi do nepotrebne redundancije podataka i gubitka vremena kod unosa, te kasnije kod održavanja podataka. U radu je izvršeno povezivanje dva sustava koji u praksi uglavnom rade nezavisno, a koriste isti fond podataka i bitni su za poslovno odlučivanje. Rezultati proračuna i analiza prezentirani u GIS-u. Kao predstavnik GIS softvera korišten je GE SW - DeGIS, dok je kao aplikacija za proračune korišten Neplan. The majority of data about network and about elements in power distribution are stored in GIS. GIS and the application for calculation need the same technical data about components in power distribution network. These systems usually work separately, resulting in huge redundancy and loss of time for data input and data maintenance. The focus of this master thesis is integration of the two systems and representation of the results in GIS. The result of calculation and analysis is very important in business decision-making and it is required to be regular and fast. GE SW-DeGIS is the representative of GIS, while a representative of applications for calculation is Neplan.

Proračun sigurnosti elektroenergetskih mreža...

Detta examensarbete beskriver hur en Monte Carlo simulering (MCS) kan användas för tillförlitlighetsanalys av ett eldistributionssystem. Metoden har implementerats i verktyget RADPOW som nu kan utföra både analytiska och numeriska beräkningar. Angreppssättet för att utveckla denna MCS metod i RADPOW innefattade följande aktiviteter: • Vidareutvecklade av RADPOW med införandet av ett grafiskt användargränssnitt för Windows. • Utveckling och implementering av en iterativ analytisk metod för känslighetsanalys av eldistributionssystem i RADPOW. • Utveckling och implementering av MCS metoden i RADPOW, vilken placerades i en fristående modul kallad Sim. Den implementerade MCS metoden har validerats i en jämförande studie innefattande två testsystem med datorprogrammet NEPLAN. Resultat från denna studie visar att MCS metoden ger samma resultat som den analytiska metoden i RADPOW och det kommersiella verktyget NEPLAN. This master thesis describes an implementation of a Monte Carlo Simulation (MCS) method for reliability assessment of electrical distribution systems. The method has been implemented in the reliability assessment tool RADPOW which now is able to perform both analytical and simulation evaluations. The main contributions within this thesis includes the following activities; • Further development of RADPOW by the introducing of a graphical user interface for Windows. • Development and implementation of an analytical sensitivity analysis routine for RADPOW. • Development and implementation of a sequential MCS method in RADPOW in a stand alone module referred to as Sim. The implemented MCS method has been validated in a comparable study for two case systems by a commercial software NEPLAN. Results shows that the implemented MCS method provides the same results as the analytical method in RADPOW and the NEPLAN software.