Assessment of load reduction capabilities using passive and active control methods on a 10MW-scale wind turbine

Abstract

In the paper, the potential to alleviate wind turbine loads through combined implementation of different passive and active control methods is assessed. Passive control of loads is accomplished through blade designs with build in material and/or geometric bend-twist coupling (BTC). The first is materialized by introducing an offset angle on the plies of the uni-directional material over the spar caps of the blade, while the latter by sweeping the blade elastic axis with respect to the pitch axis. Active control of loads is considered through individual pitch control (IPC) or concurrent use of individual pitch and flap control (IPC+IFC). Different combinations of the abovementioned techniques are tested in the paper with the aim to obtain maximum possible load reduction levels but also confine key design parameters of the various methods within reasonable limits that by no means exceed manufacturing constraints. The performance of the different control options is assessed through aeroelastic simulations for the 10MW DTU Reference Wind Turbine (RWT). A subset of representative fatigue and ultimate design load cases (DLCs) of the IEC is simulated and load reduction levels are assessed with respect to the baseline RWT configuration with no aeroelastic control of loads.