Towards Development of Equivalent Model of Hybrid Renewable Energy Source Plant for Small Disturbance Stability Studies

Over the past years, the focus of the research on hybrid renewable energy source (HRES) plants has been on the economic advantages of their integration into power systems. This paper investigates the contribution of the HRES plant to system small disturbance stability and proposes dynamic equivalent model (DEM) of HRES plant for small disturbance stability studies. The analysis takes into consideration typical annual HRES plant compositions identified by applying a clustering method to historical plant production data. Damping and frequency of the least damped electromechanical mode are used for assessing the similarity in the impact of HRES plant compositions on system stability. A transfer function-based DEM of the whole HRES plant is then proposed for each group of plant compositions resulting in similar system stability performance. The results have shown that a small number of low-order DEMs can represent the whole plant in small disturbance stability studies during the year.