Effects of induction and wake steering control on power and drivetrain responses for 10 MW floating wind turbines in a wind farm

Abstract

This paper aims to investigate the drivetrain load response caused by induction and wake steering control on two floating wind turbines (FWTs) in a wind farm. In this study, two DTU 10 MW turbines, supported on the nautilus floater, are modelled using FAST.Farm. The downstream turbine is placed at the distance of seven rotor diameters (D) from the upstream turbine in the positive wind direction. Partial wake shading is considered for wake steering control and full wake shading is considered for induction control. An ambient wind speed of 8m/s is used and a representative sea state is selected. The test cases are defined based on different blade pitch and yaw angles of the upstream turbine. Power generation of the offshore wind farm is studied under different test cases. A decouped analysis approach is used to investigate drivetrain response. Global responses are obtained from FAST.Farm. These loads are used as input of the 10 MW wind turbine drivetrain model for the gears and bearings load response analysis. Results show that both induction and wake steering control lead to a limited increase in power generation of the wind farm. Additionally, both control methods affect the drivetrain response statistics, while the features are different. This study facilitates a better understanding on drivetrain dynamic behaviour in a wind farm perspective, which serves as a reference for the wind farm optimizaton in the future.