Renewable Energy Sources (RES), and especially wind turbines (WT) as the most mature technology, will provide a large share of energy generation in a future sustainable power system. This development introduces several challenges that need to be addressed in order to ensure a safe transition away from the fossil-fuel based generation. One of the segments where RES will have a major impact is ancillary services, such as frequency support. Until now, RES (Wind & Solar) did not participate at frequency regulation of the system, which will change as their numbers in the grid increase. The contribution of this paper is the investigation of the system impact of wind generation, when wind turbines are equipped with a control system that provides frequency related ancillary services. More specifically, we analyze primary frequency response and inertial response in the case when Doubly Fed Induction Generator (DFIG) wind turbines are equipped with Energy Storage Systems (ESS). The results are presented for different levels of RES penetration and different levels of ESS deployment@en

Generation from Wind Turbines has a minimal impact on the environment compared to traditional energy sources. Renewables can effectively tackle the problems which arise with fossil fuel usage. The most considerable disadvantage of the Renewable Energy Sources (RES), and also Wind Turbines, is that, since they are inverter-based they cannot inherently support system’s frequency. Thus, when their penetration is increased, the systems stability and reliability are endangered. Moreover, nowadays RES are mostly rewarded only for providing Active Power to the grid; thus, they did not participate in voltage regulation. This situation can risk the voltage stability of the system with high renewable penetration. The contribution of this paper, is an integrated control system which is capable of providing frequency and voltage support to the grid, while operating the Wind Turbine at its optimal point, by utilizing an Energy Storage System. The design and the simulation of this system was performed in real-time with RTDS.@en