Innovative power system event-detection and synchronous plant emulation technique for large wind power plant

The subject matter of this thesis report investigates a synthetic inertia and dynamic stability technique for grid inter-connection of large VSC-HVDC connected offshore windfarms. Assuming traditional load frequency control on the AC grid for the short-term reallocation of power generation resources due to load disturbances, this technique ties...

Enhancing the Features of Vertical Axis Wind Turbines with Active Flap Control and Airfoil Design

In recent years, the research on Vertical Axis Wind Turbines (VAWTs) have been paving the way for the very large-scale (10-20 MW) floating offshore applications. For a cost effective utilization, VAWTs need to deliver superior aerodynamic and structural performance. Nowadays, the complex ow phenomenon of VAWTs have been better understood and the...

DC/DC Converters in Multi-terminal HVDC System for Integrating Offshore Wind Farms

The development of far-offshore wind farms and other large-scale renewable energy sources, together with the increasing needs for long distance power transmission is resulting in more HVDC systems being integrated into the traditional AC power network. Due to the capability for operation in isolated AC grids, VSCs are becoming the preferred...

A numerical investigation of using flap control on VAWTs

The renewable energy need facilitates the development of offshore wind power. The abundant wind resource has pushed the wind farms into deep water sites. The floating VAWT concept is emerges as the times require. This research is part of Deepwind concept development. The project focuses on verifying the feasibility of using flap control to...

Flutter of a Wind Turbine Airfoil: A Parametric Study of High-Amplitude Limit Cycle Oscillations by means of Numerical Simulations

In order to be more competitive with conventional, polluting energy resources, the levelised cost of energy (LCoE) of wind turbines has to decrease significantly [1]. A method to achieve this goal is to reduce the amount of parts in a wind turbine and more specifically avoid the use of expensive and failure-prone pitch systems. Using blades...

3D Lagrangian VPM-FMM for Modelling the Near-Wake of a HAWT: The development of a stable, accurate, and efficient numerical solver for large-scale wind energy purposes

Traditionally, the design of the Horizontal Axis Wind Turbine (HAWT) has relied on momentum-based methods such as the Blade Element-Momentum (BEM) models. With the growth of computational power, optimization of wind turbines by using Computational Fluid Dynamics (CFD) for the explicit wake modelling is becoming more mainstream. Wake modelling is...

Dynamic Stall on Vertical Axis Wind Turbines: Creating a benchmark of Vertical Axis Wind Turbines in Dynamic Stall for validating numerical models

Single Blade Installation for Large Wind Turbines in Extreme Wind Conditions: A Quasi-Steady Aeroelastic Study in High Wind Speeds under Different Inflow Angles

Energy demand from wind greatly increases, as such more remote sites need to be explored in order to find good wind resources. These remote sites are driving the industry further offshore and therefore into extreme wind and sea conditions. This push towards extreme conditions requires technological advancements concerning the wind turbine loads,...

Cost Model for Floating Multi-Megawatt Vertical Axis Wind Turbines: With a Focus on the DeepWind Concept

In an effort to achieve economic sustainability, the major challenge for offshore wind remains to bring down costs by approximately 35 % before 2020. With wind farm sites going into deeper waters, further from shore, with more difficult bottom conditions and rougher wave climate, costs are rising faster than the improvements in the technology...

Experimental and numerical study on harmonically pitching airfoils with morphing trailing edge flaps

A new LLJ model and its application to wind turbine power analysis

Low level jets (LLJs) are situations where wind speed maximums occurs close to the surface. Unfortunately, the influence of LLJs on wind turbine power production is still difficult and costly to quantify due to that the existing LLJ models are all time-based. The work that is done in this report addresses the research question should low level...

Design Requirements for 2-D Aero-elastic Experiments on Airfoils

Given the prime importance of wind tunnel setup when it comes to aero-elastic study, the main intent of this project is to devise a mechanism for supporting system of 2D aero-elasticity experiment in the Red Wind Tunnel Facility at DTU that allows three-degree-of-freedom motion of the rigid model. This project work is mainly inspired by the fact...

Assessment, Development and Validation of Wind Turbine Rotor Noise Prediction Codes

Wind turbine noise has become an important issue when developing onshore<br/>wind farms as turbines have scale up rapidly in the latest decades. The interest of this project is focused on the characterization and modelling of noise as a source based on the specific physics from wind turbines. A dedicated evaluation of wind turbine noise...

Structural Optimization Of A Vertical Axis Wind Turbine With Aeroelastic Analysis

Currently, the price per kW of offshore wind energy is 55% larger than onshore [38, 52]. Of this price, the rotor corresponds to 22%. To reduce the price of wind energy, it is necessary to investigate wind turbine concepts with scales above 10 MW. The commonly known Horizontal Axis Wind Turbine (HAWT) requires offshore a large support structure....