Frequency dependent voltage control by DER units to improve power system frequency stability

This paper presents a new methodology to improve the frequency stability of power system with the large integration of distributed energy resources. Distributed energy resources don´t contribute to the inertial response of the system as they are decoupled from the grid by the converters. The capability of the distributed energy resources especially (PV and Wind) to provide active power support in case of major generation outage is also limited; therefore this paper presents a novel frequency control method based on the voltage dependency of the loads. In this way, the distributed energy resources can contribute to regulate the frequency of the power system by reactive power control. In this paper the idea of frequency dependent voltage control will be demonstrated by utilizing DFIG (Doubly-Fed Induction Generator) based wind turbines.