Grid-Forming and Grid-Following Based Stability Assessment of Large-Scale Renewable Integrated Power Systems Under Low-Inertia Conditions

Abstract

Relevance: Low-inertia renewable-integrated power systems face increasing frequency and voltage stability chal
lenges under high penetration of inverter-based generation.
Objective: This study develops a mathematical–simulation model for evaluating frequency and voltage stability
in renewable-integrated power systems using GFL/GFM inverter dynamics, equivalent grid characteristics, virtu
al inertia, and reactive power control under varying renewable penetration scenarios.
Methods: Thevenin-based equivalent modeling, dq-frame inverter control, virtual inertia, droop algorithms, and
parametric dynamic simulations were applied.
Results: Increasing GFL penetration reduced effective inertia, enlarged frequency oscillations, and prolonged
stabilization time, while GFM units-maintained voltage and frequency recovery stability.