Reset controllers are commonly used to smooth the transient response of systems. We use this technique to improve a standard baseline pitch controller for offshore wind turbines (WTs). The introduction of this strategy enhances the overall performance of the WT. In particular, the fore-aft and side-to-side accelerations of the WT tower are significantly reduced, whilst a steadier power output i...

The need for different numerical models with varying degrees of simplification for the conceptual design of a floating offshore wind turbine is the focus of this paper. While parts on the component level can be designed apart from the others the overall dynamics on the system level have to be assessed from the beginning. Starting with very simple models and identifying the significant contribut...

We investigate the suppression of the vibrations of a wind turbine tower using colocated feedback to achieve strong stability. We decompose the system into one model describing the vibrations in the plane of the turbine axis and another model in the plane of the turbine blades. In the plane of the turbine axis, we obtain a non-uniform Spacecraft Control Laboratory Experiment (SCOLE) model with ...

The exhaust air energy recovery wind turbine generator is an on-site clean energy generator that utilizes the advantages of discharged air which is strong, consistent and predictable. Two vertical axis wind turbines (VAWTs) in cross-wind orientation which are integrated with an enclosure are installed above a cooling tower to harness the discharged wind for electricity generation. It is mounted...

The current key challenge in the floating offshore wind turbine industry and research is on designing economic floating systems that can compete with fixed-bottom offshore turbines in terms of levelized cost of energy. The preliminary platform design, as well as early experimental design assessments, are critical elements in the overall design process. In this contribution, a brief review of cu...

This research paper presents preliminary results on a behavioural study of a free yawing downwind wind turbine. A series of wind tunnel tests was performed at the TU Delft Open Jet Facility with a three bladed downwind wind turbine and a rotor radius of 0.8 meters. The setup includes an off the shelf three bladed hub, nacelle and generator on which relatively flexible blades are mounted. The to...

In this paper, a wind turbine simulator is developed using PSCAD. The wind turbine static characteristics are modeled using the relation among the turbine power, the wind speed, and the blade pitch angle. Also, the dynamic characteristics of the wind turbine are modeled through a two-mass oscillating system, representing the turbine and the generator connected by elastic shaft. The system consi...

The degradation of onshore, reinforced-concrete wind turbine foundations is usually assessed via above-ground inspections, or through lengthy excavation campaigns that suspend wind power generation. Foundation cracks can and do occur below ground level, and while sustained measurements of crack behaviour could be used to quantify the risk of water ingress and reinforcement corrosion, these crac...

This paper is concerned with bump-less transfer of parametrized disturbance observer 1 based controller (DOBC) with Individual Pitch Control (IPC) strategy for full load operation of wind 2 turbine. Aerodynamic cyclic loads are reduced by tuning multivariable DOBC with the objective 3 to reduce output power fluctuation, tower oscillation and drive-train torsion. Furthermore tower 4 shadow and w...

The wind turbine foundation serves as a permanent construction in the harsh marine corrosive environment, its anticorrosion design is essential to the safe use of the wind turbine structure. At present, there is a significant controversy over the local corrosion mechanism (such as pitting corrosion, and crevice corrosion) and its diffusion mechanism in the academic circle. In the paper, the Far...