Stabilization of Grid-Forming Converters by Means of Enhanced DC-Link Voltage Control

Grid-connected converters are increasingly utilized as the interface between distributed energy resources and utilities. However, they may encounter transient stability issues during grid faults, particularly when considering the dc-link effect. In the literature, the impact of dc-link voltage control on the transient stability has been discussed, while it is not fully explored. More importantly, the dc-link voltage control for transient stability enhancement has been seldom studied. This paper analyzed the impact of dc-link dynamics on the transient stability of GFM converters and proposes an enhanced dc-link voltage control strategy specifically designed to enhance transient stability. Theoretical analysis and validations have been provided to verify its effectiveness.