A Baseline Repositioning Controller for a Floating Offshore Wind Farm

Abstract

This paper presents a baseline repositioning controller for floating offshore wind farms. It is assumed that each turbine in the farm receives a lateral position reference command by a high-level wind farm controller. A low-level controller for each wind turbine in the farm manipulates the aerodynamic force direction and magnitude to achieve the reference command, while either power maximization or power regulation at the rated power is sought depending on the generator speed feedback signal. The low-level repositioning controller is a combination of the existing controller of blade pitch angle and generator torque, and the gain-scheduled proportional-integral nacelle yaw controller. To validate the repositioning controller, a previously-developed low-fidelity dynamic wind farm simulator, called FOWFSimDyn, will be utilized. The simulation results demonstrate that repositioning wind turbines in a wind farm has a great potential in increasing the total energy capture of the wind farm with sufficiently long mooring lines. The result in this paper can be a baseline to be compared with other advanced wind farm repositioning control in future research.