Voltage Support Strength Assessment of Hybrid Power Systems Integrated with GFL and GFM Converters

With the integration of high proportion power electronic equipment in grid, traditional short-circuit ratio (SCR) and effective short-circuit ratio (ESCR) exhibit limitations in assessing the voltage support strength of hybrid power systems integrated with grid-following (GFL) and grid-forming (GFM) converters. In this regard, this paper proposes an assessment metric named the voltage support ESCR (VSESCR). Based on the analysis of the stability of different converters, the assessment of systems with GFM converters needs to consider the impact of both output reactive power and output voltage. Therefore, VSESCR introduces voltage deviation to achieve dynamic correction, and integrates the system's reactive power support and the reactivevoltage sensitivity characteristics to establish a unified dimension for strength assessment metric. Simulation results demonstrate that VSESCR can accurately assess the voltage support strength of hybrid power systems integrated with different types of converters, and reflect the critical stability threshold of various systems on a unified dimension.