| Abstract [eng] |
The thesis examines the impact of battery energy storage systems on voltage and frequency stability in electric power grid. It analyses how a battery energy storage system, by controlling active and reactive power, can improve the stability characteristics of an electric power system after the disconnection of network elements or generation sources. An IEEE 9-bus electric power system model was developed in the “DIgSILENT PowerFactory” software environment for the research. Base-case load flow analysis, N–1 contingency analysis, Q–U analysis, and dynamic frequency stability analysis were performed. During these studies, the weakest network bus was identified, the reactive power demand for improving voltage stability was evaluated, and the influence of the active power and droop parameter of the battery energy storage system on frequency stability was investigated. The obtained results showed that integrating a battery energy storage system at the weakest network bus improves voltage stability, while active power support after generation loss reduces frequency deviation and the rate of change of frequency. It was found that the droop parameter has a significant impact on the operation of the battery energy storage system. A lower droop value allows the active power reserve to be used more effectively. However, an excessively low droop value may increase control sensitivity and cause frequency oscillations. |
