Extremum Seeking Control for Multi-Rotor Wind Turbine in the Full-Load Region.

Multi-rotor wind turbines facilitate higher power production at a lower cost compared to their single-rotor counterparts. However, the larger induced loads due to yaw moments may lead to faster wear and tear on the tower structure and need be appropriately handled by means of pitch control. This paper investigates the feasibility of two different pitch control schemes based on extremum seeking principles for multi-rotor wind turbines in the full-load region. The proposed solutions are tested in simulation. Their performance is compared to that of a benchmark controller with respect to generator speed regulation, power optimisation and fatigue mitigation. The results show that the designed controllers match the performance of the conventional solution at the cost, however, of increased structural stress on the tower.