Testing and failure analysis of wind turbine gearbox
SUN Tongjin
XUAN Liang
TENG Shaowei
SU Jun
LI Yifeng
Abstract：[Objective]The wind power gearbox exhibits the highest failure rate among wind turbine components,making the rapid and accurate identification of its fault failure crucial for upgrading operational efficiency and structural reliability.To achieve this,a comprehensive and systematic failure mechanism analysis was executed on a 2.0 MW wind turbine gearbox that had been in service for nearly 10 years.[Methods]Firstly,gearbox decommissioning and complete disassembly were performed,revealing multi-level tooth surface damage across the sun gear,planetary gears,and ring gear.Subsequently,macro-morphology tracking identified planetary gear A as the primary fractured component.Localized line cutting was conducted to prepare samples for scanning electron microscopy characterization,energy dispersive spectroscopy,tensile and impact mechanical property evaluations,and metallographic examination.[Results]The macroscopic chain failure evolution trajectory of this case is as follows:Planetary gear A experiences a significant local reduction in fatigue strength due to a mixed grain defect in the core,leading to early fatigue fracture under long-term cyclic alternating loads.Owing to the inability to shut down the wind turbine immediately,the detached fragments enter the meshing zone as debris,altering the localized stress fields and causing secondary cascading failures,including brittle fractures on the sun gear and extensive plastic crushing across other gears.This premature system failure is fundamentally attributed to inadequate quality control during the forging or case-hardening heat treatment processes.
Keywords：Wind turbine gearboxFailure modePlanetary gearFatigue fracture
Publication Date：2026-07-15
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：7( 185-191 )