Inertia and primary frequency response support of VSG-controlled PMSG-WT enabled by utilization factor control of fuel cell system and ultracapacitor

• VSG-based hybrid sources with UC and FC are developed to enhance frequency support. • Novel VSG control with utilization factor enables inertial response in FC systems. • VSG with UC and FC integration improves wind turbine stability in frequency control. This work proposes integrating hybrid energy sources including ultracapacitor (UC) and fuel cell (FC) which are controlled by the virtual synchronous generator (VSG) strategy into a VSG-controlled PMSG-WT to provide frequency support. The UC emulates the traditional inertial response to manage fast-changing frequencies, whereas the FC replicates the primary frequency response. Furthermore, the novel control strategy is introduced to enable the VSG-controlled FC to support inertial response by incorporating the utilization factor concept to improve the dynamic behavior of the FC. The simulation study was conducted to confirm the effectiveness of frequency response achieved through hybrid energy sources. The results demonstrate that the proposed control method leads to proper imitation of the inertial and primary frequency response of the synchronous generator (SG) by the VSG-controlled PMSG-WT.