DFIG primary frequency regulation strategy with optimal dynamic droop control under variable wind speeds

Speed of doubly fed induction generator (DFIG) is decoupled with system frequency and system inertia is greatly reduced with increasing penetration of DFIG. It brings new challenges to system frequency security. To improve power system frequency stability, a DFIG primary frequency regulation strategy is proposed to tune droop coefficient. Taking rotational kinetic energy (RKE) into account, the droop coefficient is optimized to release both available RKE and power reserves as much as possible. The droop coefficient is optimized under different wind speeds. Comparison is made to examine the performance of the proposed method with IEEE 30 bus system.