PV power plant analysis during the work on distribution network

Diplomski rad analizira fotonaponsku elektranu instalirane snage 500 kW spojenu na distribucijsku mrežu. U radu je objašnjen rad fotonaponskih modula. Objašnjena je njihova izravna pretvorba sunčeve svjetlosti u električnu energiju i struktura. Korištenjem DIgSilent PowerFactory programa modeliran je dio mreže na koju se priključuje fotonaponska elektrana i koji se promatra u radu, modelirana je sama fotonaponska elektrana, te njeni zaštitni uređaji. Analizirani su tokovi snaga. Analiza je odrađena u promatranoj distribucijskoj mreži prije, te nakon modeliranje fotonaponske elektrane. Zaključen je pozitivan učinak elektrane na tokove snaga u mreži. Vidljivo je kako je na određenom području potreba za djelatnom snagom uzimanom iz ostatka mreže smanjila za 500 kW, odnosno za iznos snage koju elektrana daje u neposrednoj blizini mjesta potrošnje, čime su dosadašnji vodovi rasterećeni. Prilikom simulacija kratkih spojeva prikazano je kako su struje kratkih spojeva veoma visoke. Zna se kako one lako mogu dovesti do oštećenja sustava i ugrožavanja ljudi. Stoga su nam potrebni zaštitni uređaji koji će brzo prepoznati kvarove i reagirati. To je i potvrđeno pri simulacijama u ovom radu, gdje se na t-I karakteristikama vidi kako modelirani zaštitni uređaji brzo prepoznaju struje kratkih spojeva i isključe u vrlo kratkom vremenu.In this thesis analyzes a photovoltaic power plant with an installed capacity of 500 kW connected to the distribution network. The paper explains the operation of photovoltaic modules. Their direct conversion of sunlight into electricity and structure is explained. Using the DIgSilent PowerFactory program, the part of the network to which the photovoltaic power plant is connected and which is observed in the work was modeled, the photovoltaic power plant itself and its protective devices were modeled. Power flows were analyzed. The analysis was performed in the observed distribution network before and after modeling of the photovoltaic power plant. The positive effect of the power plant on the power flows in the network has been concluded. It can be seen that in a certain area, the need for active power taken from the rest of the network has decreased by 500 kW, ie the amount of power provided by the power plant in the immediate vicinity of the place of consumption, which relieves the current lines. During short circuit simulations, it is shown that short circuit currents are very high. It is known that they can easily lead to system damage and endanger people. Therefore, we need protective devices that will quickly recognize faults and react. This is also confirmed in the simulations in this paper, where the t-I characteristics show how the modeled protection devices quickly recognize short-circuit currents and turn them off in a very short time