Transient Stability Study and Optimal Parameter Selection for Hybrid Synchronous Control

A well-configured combination of Grid-following (GFL) and Grid-forming (GFM) inverters can leverage the advantages of both to enhance transient stability to some extent. However, this approach struggles to adapt to the varying operating conditions of modern renewable energy stations. To address this challenge, this paper proposes a hybrid control strategy that integrates both a phase-locked loop and a power synchronization loop, endowing the inverter with hybrid synchronization characteristics. By weighting the modulation signals of the GFL and GFM modes and dynamically adjusting the weighting coefficients, the proposed strategy optimizes synchronization performance under different voltage dip depths. Meanwhile, the optimal weighting coefficient is determined based on the Equal Area Criterion (EAC), ensuring system stability while achieving fast response. Theoretical analysis and simulation results verify the effectiveness of the proposed control strategy.