Determination of load-frequency dependence in island power supply

The measurement results of a field test in an isolated network show that the quasi-stationary load-frequency dependence in small isolated grids can be more pronounced than in large interconnected systems. In a droop-based control strategy of the power plants, the load-frequency dependence has an influence on the steady-state operating point. Therefore, a methodology for the determination of frequency-dependent characteristics of loads is presented. In the examined network, another effect occurs which is considered in this study. Transient frequency deviations have a relevant impact on the consumption of reactive power caused by transformers.