Application of four-winding transformers in distribution networks

U ovom radu opisani su modeli svih elemenata elektroenergetske mreže pri čemu je ponajviše opisan model energetskih transformatora te u zasebnom poglavlju i model četveronamotnog transformatora. Zatim je matematički opisana Newton-Raphson metoda proračuna tokova snaga te su navedeni koraci metode proračuna za elektroenergetsku mrežu. U posljednjem poglavlju dodan je jedan četveronamotni transformator koji spaja jednu realnu prijenosnu mrežu s distribucijskom mrežom na kojem su dodani jedna solarna elektrana, dva tereta te dva kabela i u ovakvoj mreži su izvršeni proračuni tokova snaga po Newton-Raphson metodi. Proračuni tokova snaga su izvršeni pri promjeni proizvodnje solarne elektrane te pri promjeni potrošnje tereta u distribucijskoj mreži na kojem je četveronamotni transformator priključen. Za svaku promjenu stanja mreže su uspoređeni rezultati u odnosu na prethodna stanja mreže te su opisani tokovi snaga unutar četveronamotnog transformatora. In this thesis the model of all elements of power grid were described, mostly the model on power transformers and in separate chapter the model of four-winding transformer. Then, the Newton-Raphson method of power flow calculation were mathematically described and the steps of this calculation method for the power grid are given. In the final chapter, a four-winding transformer was added that connects one real transmission grid with a distribution grid to which one solar power plant, two loads and two cables were added, and in that grid the Newton-Raphson power flow calculations were performed. Power flow calculations were performed when changing the production of the solar power plant and when changing the load consumption in the distribution network to which the four-winding transformer is connected. For each change in the state of the grid, the results are compared in relation to the previous states of the grid, and power flows within the four-winding transformer are described.