Fault diagnosis and failure analysis of wind turbine components

Abstract

Issues such as energy security, sustainable development and environmental protection have been a major topic of international discussions in the recent years. Wind energy is eco-friendly and does not pollute the atmosphere like thermal power plants. Repair and replacement cost of the major and precious components such as gearbox, generator and other drive train components in wind industries are very high and time consuming. Ample studies have not been taken-up to address the issues related with gearbox functionality in the wind turbine generator. Hence it is thought of worthwhile to take up this research in identifying the root cause for the problem and provide solutions to avoid the mechanism failure. In this connection, many field surveys were carried out in Indian wind site for about 8 years starting from 2004 to find out the most critical failure of mechanical components in the wind turbine gearbox to formulate the research problem. It is observed from the survey that bearing failure followed by the gear damage and shear pin failure were the major critical area to be enlighted. It is noticed that the critical failures are found in the intermediate pinion and its locating bearings, high speed pinion and its locating bearings and also in the planet gears and bearings. In some cases the slow speed bearing too have failed. Gear failure can occur independently of the bearing failure for reasons such as wear from poor lubrication, abrasion and surface fatigue initiated by bearing debris. The debris produced in the gearbox and in the bearing failure leads to abrasion of other components in the gearbox assembly. Gearbox, bearing and shear pin have been analyzed to investigate the reasons for its failure. This failure analysis will have greater utility during designing and developing the wind turbine components such as gears, shear pin and also to diagnose the bearing fault during preventive maintenance so that the mechanism for failure can be reduced.