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In the developed world, people's demands are increasing rapidly. The main peoblem is to find appropriate ways of supplying the consumption centres with the goods that are produced in distant production units. The main criteria are the preservation of the quality of the transacted goods and the minimization of the transmission losses, and both of these are affected by economic aspects, such as minimising costs. In an attempt to solve these problems, mankind has built transmission networks, such as pipelines gas networks, heat networks and electrical power networks. At first sight the question of which producer supplies a particular consumer seems to be very trivial but nowadays, with rapid developments, transmission networks are becoming more sophisticated i.e.more complex, meshed and widespread. In this paper a new network-flow-tracing method is presented. The major goal of this new method is to define flow paths from producers to consumers across a network. In the past a few methods were already proposed; however, this method is based on a matrix calculation. Altrough it considers the transmission losses, it is still very simple to understand and also very fast. The new approach was tested on the New England test power system. Since all transmission systems have some common characteristics, knowledge from one engineering field could probably be used in other fields. V razviti civilizaciji zadovoljujemo raznovrstne potrebe, vendar v ta namen potrebujemo čim bolj preprost, gospodaren in cenen dostop do dobrin. Primerna rešitev so prenosna omrežja, to so plinovod, naftovod, toplovod, električno omrežje, s katerim prenašamo snov ali energijo od proizvodnih virov do centrov porabe. Z razvojem, ki je posledica vse večjih zahtev, postajajo omrežja vse bolj prepletena. Če se vprašamo, katero pot skozi omrežje ubere neko blago iz določenega vira k določenemu porabniku, ugotovimo, da je težko neposredno odgovoriti na navidez popolnoma preprosto vprašanje. Prispevek tako predstavlja novo metodo za sledenje pretokov po omrežjih od proizvodnih virov do porabnikov. Dejansko prenosne poti ugotovimo na podlagi matričnega izračuna, ki je v primerjavi z znanimi rešitvami računsko preprostejši in z vidika potrebnega računskega časa manj zahteven. Ker je elektroenergetski sistem zapleteno omrežje, pri čemer je na voljo opazovanje pretokov električne energije smo preizkusili novo zamisel na elektroenergetskem testnem omrežju Nove Anglije, ZDA. Predvidevamo , da je novo metodo sledenja pretokov električne energije mogoče uporabiti tudi pri drugih omrežjih, ne glede na njihovo fizikalno različnost saj so osnovna načela delovanja omrežij skupna.

V magistrski nalogi smo izdelali konfiguracijo releja REL 670, ki se ga uporablja v razdelilnih postajah (RP) in razdelilnih transformatorskih postajah (RTP) za ščitenje nadzemnih vodov in kablov srednje (SN) in visoke (VN) napetosti. REL 670 smo v naši aplikaciji uporabili za krmiljenje in zapahovanje daljnovodnega polja. Slednje je pomembno zlasti zaradi zagotavljanja varnosti pred neželenimi manipulacijami stikalnih elementov, ki lahko predstavljajo nevarnost pred poškodbami opreme za elektroenergetski sistem (EES) in nevarnost udara električnega toka za človeka. Delo zajema opis releja REL 670, pregled podprtih funkcij in programiranje REL 670. Osrednji del programa je zapahovalna logika, ki preprečuje, da bi ločilke izklapljale in vklapljale breme, ker bi s tem lahko povzročili električni oblok in poškodbe na ločilkah. Poleg tega je v delu opisana samodržna vezava, ki skrbi, da na binarnih vhodih releja REL 670 ne rabimo imeti stalno prisotnega napajanja, ampak da si rele shrani zadnjo uporabljeno komando. Laboratorijski rezultati so pokazali, da predlagana konfiguracija zapahovanja daljnovodnega polja deluje ter varuje EES in uporabnika pred neustreznimi manipulacijami, ki bi lahko privedle do poškodb človeka in elementov EES. In the master thesis, we configured the REL 670 relay, which is used in distribution stations and distribution transformer stations for the protection of overhead lines and cables from medium to high voltage. In our application, we used the REL 670 to control and lock the power line bay. The latter is particularly important to ensure safety against errors in the manipulation of switching elements, which can pose a danger to people and damage of the electrical network equipment. The work describes the relay REL 670 with an overview of the supported functions and the configuration of REL 670. The main part of the program is latching logic implemented to turn the disconnectors off and on, which prevents electrical arc formation on disconnector. In addition, the second part describes a self-sustaining binding that ensures that the binary inputs of the relay REL 670 do not require a constant power supply, but stay on course with the last command used. Laboratory results show that the proposed power line bay ignition configuration works and can protect against improper tampering that could damage users and EES elements.

Operater trga z elektriko v sklopu bilančnega obračuna preverja, ali je obratovanje bilančnih skupin usklajeno z njihovim tržnim planom, zaznana odstopanja pa jim zaračunava. Strošek odstopanj za bilančne skupine ni zanemarljiv. Iz tega razloga se sprašujejo, če obstajajo načini, s katerimi bi ta odstopanja lahko učinkovito zmanjševali. Magistrsko delo obravnava modeliranje baterijskega hranilnika in njegovo vključitev med elektroenergetski sistem in odjemalca. Nadalje je opisan vpliv baterijskega hranilnika na odstopanja in z njimi povezani stroški. Predstavljen je postopek analize ekonomske upravičenosti investicije v baterijski hranilnik z upoštevanjem stroška investicije, letnih denarnih prilivov in odlivov. V delu je preko metod neto sedanje vrednosti in notranje stopnje donosa ovrednotena ekonomska upravičenost investicije za različne konfiguracije baterijskega hranilnika s stališča moči in kapacitete. Dodatno je izvedena še analiza občutljivosti ob predpostavljenih vrednostih vplivnih parametrov za leto 2025. Na koncu so podani napotki za izbiro primerne konfiguracije hranilnika, ki bi ustrezala rešitvi obravnavanega izziva. As part of the imbalance settlement, the power market operator checks that the balance groups are operating in accordance with their market plan and charges them for any deviations found. The costs of deviations are not negligible for the balance groups. Therefore, the question arises whether there are ways to effectively reduce these deviations. The thesis deals with the modelling of battery storage and its integration between the electricity system and the customer. It further describes the impact of battery storage on the deviations and the associated costs. A procedure for analysing the economic viability of an investment in a battery storage is presented, considering the investment costs, annual cash inflows and cash outflows. The economic viability of the investment is assessed for different battery storage configurations in terms of power and capacity using the net present value and internal rate of return methods. In addition, a sensitivity analysis is carried out assuming the values of the impact parameters for the year 2025. Finally, guidance is given on how to select an appropriate storage configuration to meet the challenge at hand.

Nova pridobitev Katedre za elektroenergetske sisteme in naprave je testno okolje za zaščito in daljinsko vodenje podjetja Schneider Electric. V sklopu praktičnega usposabljanja ob zaključku študijskega programa Energetska tehnika in avtomatizacija postrojev smo testno okolje vzpostavili v sistem, s pomočjo katerega bodo lahko študentje na realnih primerih izvajali laboratorijske vaje. V uvodu bo na kratko predstavljen elektroenergetski sistem (EES) ter sistemi, ki skrbijo za njegovo normalno delovanje. Na enostavnem primeru realnega srednje napetostnega polja bomo predstavili del njegovih osnovnih gradnikov in upravljanja z njimi. V prvem poglavju se bomo posvetili sestavnim delom testnega okolja. Podrobno bomo predstavili njegove sestavne dele, njihovo delovanje, povezljivost in namene uporabe. V drugem poglavju bo predstavljen praktičen potek vseh postopkov, ki so nas pripeljali do celovitega delovanja testnega sistema. Na kratko bomo predstavili osnovno shemo in projektno osnovo za sestavo testnega okolja. Bolj podrobno se bomo v nadaljevanju posvetili samemu testiranju in programski implementaciji sistema v celoto. V zaključku se bomo ozrli nazaj in ovrednotili dosežene cilje in napake, ki so se pojavile med izdelavo. Poleg tega bomo pregledali nadgradnje, ki bi izboljšale funkcionalnost celotnega sistema. The new acquisition for Department of power systems and devices is test environment for protection and remote control from Schneider Electric. As the part of the faculty mandatory practical work at the end of the program Power Engineering Technology and System Automation we established the environment into the system for faculty laboratory exercises. The electric power system and the systems which ensure its normal operation will be described in the introduction. Using a simple example of a real medium voltage field, we will present some of its basic components and their management. In the first chapter, we will focus on the components of the test environment. We will present in detail its components, their operation, connectivity, and purposes of use. In the second chapter, the practical course of all the procedures that led us to the comprehensive operation of the test system will be presented. We will briefly present the basic scheme and project basis for the construction of the test environment. In the following, we will focus in more detail on the actual testing and software implementation of the system as a whole. In conclusion, we will summarize the usability of the established system and indicate the starting points of its future use for the purposes of study processes.

Diplomsko delo obravnava vpliv spremembe konfiguracije omrežja na viške delovne in jalove energije, ki se jih potiska v visokonapetostno (VN) omrežje, na izgube na izvodu ter padce napetosti po vozliščih. Model omrežja je bil modeliran v programskem paketu Matpower na podlagi realnega razdelilnega omrežja Elektra Ljubljana, prav tako so bile za izračun pretoka moči uporabljene realne meritve za leto 2020. Na območju razdelilne transformatorske postaje (RTP) Črnomelj, ki je obravnavano v nalogi, se nahajajo štirje izvodi z veliko razpršenimi viri energije, kjer posledično prihaja do potiskanja viškov električne energije v RTP in VN omrežje. Da bi se zmanjšalo potiskanje električne energije, se je v simulacijah premikalo ločilno mesto med izvodi. Tako se je spremenila konfiguracija omrežja, s ciljem čim več električne energije porabiti v srednjenapetostnem (SN) omrežju. Prva simulacija je bila izvedena za normalno obratovalno stanje v letu 2020. Nato pa se je premikalo ločilno mesto med izvodi. Nove lokacije ločilnih mest so bile določene vnaprej, na podlagi izkušenj. Preklapljanja med konfiguracijami so bila izvedena na letnem, mesečnem, tedenskem in dnevnem nivoju. Na koncu naloge se je določil najboljši vrstni red obratovanja glede na porivanje viškov električne energije v VN omrežje, izgube na daljnovodih ter napetostne razmere na daljnovodih. This diploma thesis discusses the impact a change of network configuration has on surplus of active and reactive energy that is pushed in HV network, on losses per feeder and voltage drops on nodes. The model of network was created in programming package Matpower, based on a real distribution network of Elektro Ljubljana. The measurements that were used for power flow were also real measurements for the year 2020. In the area of electric transformation station Črnomelj, which is discussed in the thesis, there are four feeders that have many renewable energy sources. Therefore, pushing of surplus energy into electric transformation station and HV network occurs. To decrease pushing of redundant energy, the separation point between feeders was moved in simulation, thus the network of configuration changed, in order to use as much electricity as possible in MV network. First simulation was carried out for normal state in the year 2020. Then, the separation point was moved between feeders. New locations for separation points were determined in advance, based on experience. New simulations were executed annually, monthly, weekly and on daily basis. At the end of the diploma thesis, the best order of operation in regard to pushing redundant electricity to HV network, losses per feeder and voltage drops on nodes, was defined.

Intenzivnemu razvoju gospodarstva in tehnologije v zadnjih 30-ih letih sledi hiter tempo življenja. Posledično se spopadamo z vedno večjimi potrebami po električni energiji, z njimi pa rastejo tudi zahteve po novih, dodatnih proizvodnih enotah. Prvi korak poti do realizacije takšnih projektov je izdelava študije, idejnega projekta. Kmalu naletimo na problem finančne smiselnosti investicije, ki je odvisna predvsem od predvidene cene električne energije, po kateri bi elektrarna na trgu prodajala svoj proizvod. Hkrati se vztrajno višajo cene primarnih energentov in ekonomska upravičenost investicije postane zelo vprašljiva. Pojavi se dvom, kako takšne investicije realizirati. Na drugi strani želi Evropa popraviti nastalo škodo in ponovno urediti prijazen bivalni prostor. Z ukrepi uporabe nizkoogljičnega čistega transporta, samooskrbnosti lokalnih gospodinjstev in na splošno uvajanja proizvodnje zelene energije si prizadeva narediti velik korak naprej. Čeprav je strošek goriva ničeln in na okolju ne pušča nezaželenih učinkov, so tovrstne proizvodne enote nezanesljive z vidika konstantne proizvodnje. Proizvodnja je odvisna od podnebja in vremenskih pogojev, narava pa je danes vedno bolj nepredvidljiva in kruta. Vsaka proizvodna tehnologija ima svoje prednosti in slabosti. V skladu z gospodarskimi in osebnimi potrebami po električni energiji ter interesi in političnimi načeli je potrebno najti kompromis – kompromis s ciljem izboljšanja življenjskega prostora in hkrati zadostiti vsem zahtevam porabnikov. V magistrski nalogi so predstavljeni različni scenariji soočanja z omenjenimi vprašanji in problematikami. Razlag in rešitev je veliko. Vsaka izmed njih pa je komentirana po principu objektivnega mnenja ekonomista, ki ga inženirji prepričujejo v investicijo. An intensive economic and technological development in the last thirty years has lead to a faster way of life. Consequently, our demands for electrical energy along with the need for new production units are rapidly growing. The first step to accomplishing such projects is the development of a study - an ideal project. When we take on such a task, we soon come across a problem in the financial sense of the investment, which depends mainly on the estimated price of electrical energy at which an electrical power plant would sell its product. Along with that, the prices of primary energy sources are growing, therefore, the economical justification of the investment becomes questionable. A question of how to successfully execute such investments appears. On the other hand, Europe is trying to repair the damage and restore a pleasant living environment. They are striving for development by ensuring a cleaner low carbon transport, self-supplying local households and generally initiating a production of greener energy. Even though the costs of such fuels are low and the environment does not have to bare any negative effects, such production units are unreliable when it comes to aspect of consistent production. Namely, such production depends on the climate and weather conditions and the nature, as we know, can be highly unpredictable. Each production technology has its advantages and disadvantages. According to economic and personal needs for electricity and the interests and political principles a compromise must be found, which should aim towards improving the environment and satisfying the needs of the consumers. Various scenarios of dealing with the previously mentioned questions and problems are presented in this paper. There are many explanations and solutions and each of them is presented from an objective opinion of an economist that is being persuaded for an investment by engineers.

Diplomsko delo obravnava umeščanje individualne samooskrbe s sončno elektrarno v distribucijsko nizkonapetostno omrežje. Vedno več ljudi se odloča za priklop sončnih elektrarn, kar je v smislu zelene energije seveda zelo dobrodošlo in progresivno, vendar trenutna distribucijska omrežja prvotno niso bila grajena za ta namen. V začetku so predstavljeni razlogi odločanja za samooskrbo, prikazana je teorija sončnih elektrarn in priklop na distribucijsko omrežje, standard SIST EN 50160, ki veleva značilnosti predpisane napetosti v omrežju, opis uporabljene dokumentacije za namen postopka priklopa razpršenih virov, po katerem se distributerji v Sloveniji orientirajo, analiza primera in možne rešitve. V zaključku smo naredili analizo, ki je omogočila optimizacijo in maksimiranje proizvodnje investitorja, po drugi strani pa se distribucijsko podjetje ukvarja z zagotavljanjem kakovosti napetosti v priključnih točkah uporabnikov. This Thesis deals with the placement of a solar power plant in public distribution low-voltage network. More and more people are choosing to install solar power plants, which is of course very welcoming and progressive in terms of green energy, but the current distribution networks were not built for such purpose. In the beginning the thesis describes deciding reasons for self-sufficiency with photovoltaics, theory of solar power plants and connection to the distribution network, the SIST EN 50160 standard, which dictates the characteristics of the prescribed voltage in the network, description of documentation used for the connection process of distributed generation in Slovenia, case analysis and possible solutions. In conclusion, we made an analysis that enabled the optimization and maximization of investor’s future solar power production, while on the other hand, the distribution company deals with ensuring demanding quality of the voltage at the users’ connection points.