Abstract：Grid-forming（GFM）converter is a voltage source and has good adaptability and frequency-voltage

support in weak grid，but is prone to oscillation instability in strong grid due to impedance characteristics. To solve

this problem，based on the analysis of the impedance characteristics of the GFM converter，an adaptive optimization strategy of the GFM converter based on virtual inductance was proposed. In order to analyze the influence of control mode on the grid-connected stability of GFM converter，the sequence impedance model of GFM converter with direct amplitude-phase control was modeled in detail. Secondly，the influence of power grid and filter inductance on the grid-connected stability of GFM converter was studied，and its instability scenario was defined.Finally，a hardware-in-loop real-time simulation test platform based on RT-LAB and DSP controller was built，and the strategy was experimentally tested from different virtual inductance parameters，which verifies the effectiveness and superiority of the proposed strategy.

      Key words：grid-forming（GFM）converter；sequence impedance modeling；stability analysis；virtual inductor；strategy optimization