Transient stability augmentation of hybrid power system based on synthetic inertia control of DFIG

Integration of large scale renewable energy sources (RESs), such as: wind power and photovoltaic (PV) plants, into the power system decreases the dependence on fossil fuel. Therefore, the total system inertia will be reduced because of gradual replacement of the conventional synchronous generators (SGs). This paper proposes a new method to enhance the transient stability of the power system with RESs introduced, in which variable speed wind turbine with doubly fed induction generator (VSWT-DFIG) supplies its kinetic energy (KE) during generation outage to stabilize conventional SGs. A suitable fuzzy logic based synthetic inertia controller is proposed to supply the KE effectively during transient period. This fuzzy logic controller (FLC) can continuously adjust the synthetic inertia controller gain depending upon the incoming wind speed. The effectiveness of the proposed synthetic inertia control method has been verified through simulation analyses on a hybrid power system model composed of DFIG, PV plant and SGs.