The analysis of tranisent and influence on generator during AR -automatic reclosing in network with distributed generation

Glavni zadatak ovog rada bilo je analizirati prijelazne pojave i utjecaj automatskog ponovnog uklopa na glavni izvor svakog sustava, generator. Kao realan primjer, elektrana na biomasu „Viridas“ priključena na distributivnu mrežu trebala je dati odgovor na taj problem. Sve simulacije vršene su u programskom paketu ATP -EMTP, programu specijaliziranom za tranzijentne pojave u elektrotehnici. Simuliranjem trofaznog i jednofaznog kratkog spoja u mreži sa uzemljenjem, pojasnilo se ponašanje struja i napona generatora u prijelaznom vremenu između dva isklopa prekidača. Na osnovu dobivenih rezultata, može se zaključiti kako je trofazni kratki spoj nepovoljniji zbog većih vrijednosti struja, ali i zbog kolapsa napona u sve tri faze. Također, ovaj rad je pokazao prednost svojstva selektivnosti zaštite.The main assignment of this paper was to analyze transient phenomena and impact of automatic reclosing of the switch on generator. Like realistic example, „Viridas“ biomass power plant connected to distributed grid needed to answer that problem. All simulations was made in simulation program ATP – EMTP which is specialized for transient phenomena in electrical engineering. By simulating three phase and single phase fault in grid with ground connection, it was explained current and voltage conditions of the generator in transient time between two openings of the switch. Based on obtained results, it can be concluded that three phase fault is unfavorable because of higher value of the currents and because of collapsing of the voltage in all three phases. Also, this paper shows benefit of selectivity of protection