From Grid-Following to Grid-Forming: A Review of Converter Technology Paradigm Shift and Its Applications in Renewable-Rich Power Systems

Abstract

With the global penetration of renewable energy exceeding 30%, power systems are increasingly challenged by inertia deficiency and weak grid stability, exposing the limitations of conventional grid-following inverters (GFLI) which rely on external synchronization and may provoke sub-synchronous oscillations. This review analyzes the technological transition toward grid-forming inverters (GFMI)—capable of autonomously establishing and regulating voltage and frequency—and assesses their application in renewable energy systems. Through bibliometric analysis, case studies from major Chinese renewable bases, and hardware-in-the-loop simulations under weak-grid conditions (SCR as low as 1.0), we identify significant advancements in wide-bandgap semiconductor topologies, adaptive control strategies such as virtual synchronous generator (VSG) and self-synchronizing control (SSC), impedance reshaping, and fault ride-through capability. Real-world implementations demonstrate markedly improved performance: inertia response time reduced to 0.48s, suppression of sub-synchronous oscillations by 89%, reactive response within 25ms, and successful black-start within 180 seconds, alongside notable economic benefits including reduced wind curtailment and lower equipment costs. Nevertheless, widespread adoption faces standardization gaps particularly in thermal management of high-frequency devices, multi-timescale stability certification, and market mechanisms for ancillary services. We conclude that GFMI represents a foundational technology for future high-renewable power systems, though its full deployment requires integrated progress in adaptive intelligence, international standard alignment, and policy-supported market frameworks.