Synchronization stability analysis and damping reshaping control for grid-following PMSG with virtual inertia control

• To satisfy the frequeresponse requirements of the power system, VIC has been incorporated into the system regulation. • The DC-link serves as a coupling bridge between the machine-side and grid-side systems. • VIC and MCCs can affect the output power angle characteristics of the PLL. • The implementation of the damping reshaping control strategy,compensates for negative damping, ensuring positive damping and enhances the stability of the GFL-PMSG. The virtual inertia control (VIC) has been widely adopted in grid-following permanent magnet synchronous generator-based (GFL-PMSG) wind turbines to meet the grid connection standards. However the critical impacts of VIC on power angle characteristics and synchronous stability remain inadequately investigated. Besides, the design of VIC seldom addresses the impact of multi-loop control couplings (MCCs) on synchronous stability. To this end, a complex torque analysis method is proposed to precisely quantify damping torques.The analysis reveals two critical insights: (1) the VIC and MCCs introduce an equivalent additional feedback loop into the PLL; (2) this additional feedback loop generates negative damping, which adversely affects the power angle characteristics and ultimately influences the synchronization stability of the PMSG. To address this issue, a damping reshaping control strategy is proposed, integrating stator current and DC-link voltage feedforward. Finally, experimental results are presented to validate the effectiveness of the proposed damping reshaping control in enhancing the synchronization stability of GFL-PMSG systems.