Popis: |
In this research, real-time hybrid testing of floating wind turbines is carried out at model-scale. The semi-submersible, triangular platform is built to support two vertical-axis wind turbines (VAWTs). On account of incongruous scaling issues between the aerodynamics and the hydrodynamics, the wind turbines are not constructed at the same scale. Instead, remote-controlled (RC) plane motors and propellers are used as actuators to mimic only the tangential forces on the wind turbine blades, which are attached to the physical model. On a VAWT, the tangential force is proportional to the torque on the turbine, which contributes to the power production. A control algorithm is implemented using the wind turbine generators to optimize the platform heading and hence, the theoretical power absorbed by the wind turbines. The computer fluid dynamics simulations of two-dimensional counter-rotating turbines is briefly discussed. The results from the simulations are discussed in the context of existing onshore experimental data. This experimental approach only seeks to recreate the aerodynamic force which contributes to the power production. In doing so, the generator control algorithm can be validated. The advantages and drawbacks of this technique are discussed, including the need for low inertia actuators, which can quickly respond to control signals. |