A Review of Overvoltage Protection Technologies and Protective Devices for Wind Turbines

Wind turbines are persistently threatened by both lightning overvoltage and switching overvoltage due to their ultra-high structure, dense power electronics, and harsh operational environments, which severely endanger the safe and stable operation of the units. This paper systematically reviews the generation mechanism, type characteristics, and hazards of overvoltages in wind turbines. An internal and collaborative overvoltage protection system based on lightning protection zones (LPZs) is described. Focusing on three core protective devices—metal oxide varistors (MOVs), gas discharge tubes (GDTs), and Transient Voltage Suppressors (TVSs)—the research progress in material modification, structural optimisation, and performance evolution laws is explored. Additionally, the development of series-parallel topological collaborative design for multiple devices and active-triggered intelligent protection technologies is analysed. It is highlighted that current wind turbine overvoltage protection still faces bottlenecks in standard applicability, device operating condition adaptability, and system-level collaborative design. Future research should focus on the application of a wide bandgap and nanomaterials, the improvement of test standards tailored for actual operating conditions, and the construction of multi-physics coupling simulation and active intelligent early warning protection systems, so as to provide theoretical and technical support for high-reliability overvoltage protection of large-capacity and offshore wind turbines.