Summary
This paper investigates the technical and regulatory challenges associated with the protection and control of inverter-based resources (IBRs) in power systems with high penetration of power-electronic-interfaced generation. The replacement of synchronous machines by photovoltaic, wind, and battery-based resources has altered fault behaviour, voltage dynamics, and short-circuit characteristics, challenging conventional protection philosophies. In response, grid codes have evolved to impose Fault Ride-Through (FRT) requirements, reactive current support, and voltage-dependent control obligations on IBRs. However, interactions between inverter control functions, particularly Phase-Locked Loops (PLLs), Low Voltage RideThrough (LVRT), High Voltage Ride-Through (HVRT) logic, overvoltage protections, and transmission system dynamics remain a major source of unintended plant disconnections and active power loss during grid disturbances and fault recovery periods. A comparative review of international grid codes is presented, covering Europe, North America, Latin America, AsiaPacific, and Nordic countries, with emphasis on protection-relevant requirements, including reactive-current injection factors, priority modes, negative-sequence current behaviour, and restrictions on momentary cessation. The paper further analyses a real disturbance event in the
Read more Read lessBrazilian Interconnected Power System (BIPS), involving a 500 MW photovoltaic power plant.
A remote single-phase-to-ground fault triggered inverter PLL dynamics, partial inverter disconnection, and an instantaneous active power loss of approximately 280 MW. During resynchronisation, prolonged operation near the upper HVRT boundary resulted in overvoltage protection trips after the HVRT timeout. Based on oscillographic records, inverter logs, and grid-code requirements, the root causes were identified and mitigation measures proposed, highlighting the need for closer alignment among grid-code specifications, inverter control design, and protection system requirements.
Additional informations
| Publication type | Session Materials |
|---|---|
| Reference | B5_11042_2026 |
| Publication year | |
| Publisher | CIGRE |
| Country | Brazil |
| Study committees | |
| File size | 788 KB |
| Price for non member | 30 € |
| Price for member | 30 € |
Authors
FERNANDES Rafael - Equans Brazil; SILVA Gustavo - Auren Energia Brazil; DUTRA Ricardo - Consultant Brazil
Keywords
Inverter-Based Resources, Grid-Code, Regulatory Process, GFL, GFM, Disturbance, Protection and Control Systems
