Life extension of wind turbine gearboxes based on pitch control

• Focuses on optimization of wind turbine performance and maintenance strategies • Novel approach based on pitch control extends the remaining useful life of wind turbine gearboxes • Proposed approach effectively increases gearbox remaining useful life and power generation • Apart from life extension, economic benefits for wind farm operators maximized • Practical solution to improve sustainability and economy of wind energy systems The gearbox is an important part of a wind turbine, and its faults account for a high proportion of wind turbine faults and cause great harm. To address this problem, many wind farms have installed condition monitoring systems that make it possible to give early warnings before their failure. Owing to the lack of effective life extension strategies, most wind farms usually directly perform maintenance on the gearbox after receiving a warning signal. However, the operation and maintenance of only one gearbox at a time increases the cost of a wind farm. Aiming to solve this problem by using data collected from a wind farm located in northwest China, a remaining useful life prediction model is established via transfer learning and long short-term memory. Subsequently, a life extension strategy of wind turbine gearboxes is proposed by changing the pitch angle, and the impact of the pitch angle on the remaining useful life of the gearbox is analyzed. Subsequently, the economic benefits of longevity are analyzed. The results show that the life of the gearbox used in this study can be can be extended by up to 500 hours and that the maximum increase in power generation is approximately 7.2%.