Vedrana Jerković, Željko Špoljarić, Damir Šljivac

Abstract
The aim of this paper is to test stability of a small biogas plant in an electric power system and the possibility of island mode as well. A short description of a biogas plant with two 1 MW generators is given in the introductory part. Furthermore, generator and regulator modeling as well as modeling of the surrounding electrical grid in software package PowerWorld Simulator are described. Operation simulations of this power system show that the system is stable in terms of short-period disturbances. Finally, the possibility of island mode operation of the biogas plant loaded with part of the surrounding electrical grid in the case of blackout is tested. It is shown that island mode is possible and reasonable in the case of longer blackout.
Keywords
biogas plant, disturbances, generator modeling, island mode, stability