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U postupku davanja suglasnosti na visinu tarifnihstavki, Hrvatska energetska regulatorna agencijadaje suglasnost na trogodiπnje planove razvojai izgradnje prijenosne, odnosno distribucijskemreæe. Tako se u drugom Ëlanku daju komentarina razliËite aspekte regulatorne politike, koja uvelikoj mjeri moæe utjecati na razvoj prijenosne idistribucijske mreæe te na poslovanje subjekatakoji obavljaju regulirane djelatnosti.Model transformatora primjenjiv u niskofrekvencijskimelektromagnetskim prijelaznim pojavamas frekvencijama reda veliËine pribliæno 1 kHz, prikazanje u treÊem Ëlanku. U radu se polazi od matematiËkogi analitiËkog modela, a zatim je zbogograniËenja analitiËkog modela u analizu uvedennumeriËki pristup rjeπavanja krutih diferencijalnihjednadæbi koje opisuju prijelaznu pojavu.Razvijeni algoritam moæe se uspjeπno koristiti uostalim niskofrekvencijskim prijelaznim pojavamagdje je glavni predmet analize nelinearni karaktertransformatora.»lanak skupine autora iz GrËke daje saæet prikaz ianalizu raspada elektroenergetskog sustava otokaRodosa. Opisani i dijagnosticirani raspad elektroenergetskogsustava vrlo je zanimljiv s obzirom dase radi o izoliranom sustavu u kojemu se sukcesivnodogaapplea nekoliko poremeÊaja razliËitih uzroka iposljedica.Posljedni Ëlanak obraappleuje temu baze podataka, uovom sluËaju podataka o relejnoj zaπtiti. U dobrostrukturiranom Ëlanku daje se model koriπtenjabaze svih relevantnih podataka vezanih uz relejnuzaπtitu i to na naËin da se koristi relativno lakodostupan komercijalni program. Posebna znaËajkaovog modela upravljanja bazom podataka jenjegova jednostavnost, πto znaËi da potrebna razinaznanja o tehnikama baza podataka te naËinupretraæivanja i Ëuvanja podataka ne mora bitivisoka.»lanke u ovom broju Ëasopisa Energija potpisujedvanaest autora iz sveuËiliπne zajednice, ali i izprakse, πto je, vjerujem, rezultiralo i kvalitetnimËlancima.As part of the procedure for authorizing the amountsof tariff items, the Croatian Energy RegulatoryAgency authorizes three-year development andconstruction plans for transmission and distributionnetworks. The second article provides commentarieson various aspects of the regulatory policy, whichcan have a considerable impact upon the developmentof the transmission and distribution networks,as well as the operations of the regulatory bodies.In the third article, a transformer model is presentedthat is applicable to low frequency electromagnetictransient phenomena of up to 1 kHz. The articlefirst presents analytical and mathematical models.Due to the limitations of the analytical model, anumerical approach is introduced for the solutionof the stiff differential equations that describe thetransient phenomena. The algorithm developed canbe used successfully in other low frequency transientphenomena where the main subject of analysisis the nonlinear character of the transformer.An article by a group of authors from Greece summarizesand analyzes a blackout that occurred in theelectrical energy system on the island of Rhodes.The description and diagnosis of the system blackoutis very interesting because it concerns an isolatedsystem in which there were successive perturbationswith various causes and consequences.The last article concerns the topic of databases,in this case data on relay protection. This wellstructuredarticle presents a relay protection datamodel using the easily obtainable Microsoft AccessDatabase Program. A particular characteristic ofthis model of database management is its simplicity,which means that the required level of userknowledge regarding database techniques, searchesand data storage need not be high.The articles in this issue of the journal Energija aresigned by twelve authors from the university andenergy bussines.Editor-in-ChiefGoran Slipac, MScGlavni urednikmr. sc. Goran Slipac525