Performance Analysis on the Use of Oscillating Water Column in Barge-Based Floating Offshore Wind Turbines

Abstract

Undesired motions in Floating Offshore Wind Turbines (FOWT) lead to reduction of system efficiency, the system’s lifespan, wind and wave energy mitigation and increment of stress on the system and maintenance costs. In this article, a new barge platform structure for a FOWT has been proposed with the objective of reducing these undesired platform motions. The newly proposed barge structure aims to reduce the tower displacements and platform’s oscillations, particularly in rotational movements. This is achieved by installing Oscillating Water Columns (OWC) within the barge to oppose the oscillatory motion of the waves. Response Amplitude Operator (RAO) is used to predict the motions of the system exposed to different wave frequencies. From the RAOs analysis, the system’s performance has been evaluated for representative regular wave periods. Simulations using numerical tools show the positive impact of the added OWCs on the system’s stability. The results prove that the proposed platform presents better performance by decreasing the oscillations for the given range of wave frequencies, compared to the traditional barge platform.

Complementary Airflow Control of Oscillating Water Columns for Floating Offshore Wind Turbine Stabilization

“…For the barge-type FOWT, the most significant DOFs affecting the tower loads of the wind turbine structure are the platform pitch motion and the tower first fore-aft bending mode [15,30]. Thus, these two DOFs are used in the design of the simplified reduced-order wind turbine model, and its scheme is shown in Figure 2, adopted from [12,17].…”

Estabilización de eólica marina flotante mediante control de flujo de aire en columnas de agua oscilante

“…Para el FOWT de tipo barcaza, los grados de libertad más importantes que afectan las cargas de la torre de la estructura de la turbina eólica son el movimiento de inclinación de la plataforma y el primer modo de flexión longitudinal de la torre [16,17]. Por lo tanto, ambos se utilizan en el diseño del modelo simplificado de turbina eólica de orden reducido, y su esquema se muestra en la Figura 1.…”

Switching Control Strategy for Oscillating Water Columns Based on Response Amplitude Operators for Floating Offshore Wind Turbines Stabilization

“…Jonkman in [21] designed a square-shaped moonpool placed at the barge's center that provides the option of adding an OWC within the tower of the wind turbine, but this hybrid system has not designed for the purpose of stabilization. P. Aboutalebi et al in [22] analyzed the performance of the hybrid barge-type FOWT-OWCs under different sea states to increase the stability of the system. However, the introduced approaches have not proposed a strategy to control the valves of OWCs.…”