Method of increasing equivalent damping in DC voltage synchronous control based on additional low-pass filter feedback

Based on Direct Voltage Synchronization Control (DVSC), the grid-forming converter can stabilize the DC side voltage while achieving self-synchronization. However, traditional DVSC only simulates the inertia of synchronous machines and cannot emulate damping, which can lead to lowfrequency oscillations. To examine the similarities and differences between DVSC and synchronous machines, this paper analyzes their equivalent relationships. Based on the analysis of low-frequency oscillation mechanisms, an improved DVSC control method with an additional low-pass filter feedback loop is proposed to achieve damping simulation effects similar to those of synchronous machines. In the end, the effect of the proposed method is verified through simulations.