Wind tunnel experiments to prove a hydraulic passive torque control concept for variable speed wind turbines

In this paper the results are presented of experiments to prove an innovative concept for passive torque control of variable speed wind turbines using fluid power technology. It is demonstrated that by correctly configuring the hydraulic drive train, the wind turbine rotor operates at or near maximum aerodynamic efficiency for below rated wind...

Influence of the rotor nacelle assembly mass on the design of monopile foundations

In light of the developments of the offshore wind industry in terms of water depth and turbine size, the objective of the research presented in this paper is to gain insight in the applicability limits of the monopile support structure for large offshore wind turbines. This is done by demonstrating how the mass of the rotor nacelle assembly (RNA...

On the Application of Fluid Power Transmission in Offshore Wind Turbines

Offshore wind energy is currently characterized by the high costs associated with installation and operation. Gearboxes in particular have been singled out as a key source of the high maintenance costs of offshore wind farms. For a given wind speed, the torque of the rotor increases cubically with the diameter of its swept area. As the maximum...

Dynamic Analysis of Fluid Power Drive-trains for Variable Speed Wind Turbines: A Parameter Study

In the pursuit of making wind energy technology more economically attractive, the application of fluid power technology for the transmission of wind energy is being developed by several parties all over the world. This paper presents a dynamic model of a fluid power transmission for variable speed wind turbines and shows a parametric study on...

Dynamic transmission response of a hydrostatic transmission measured on a test bench

Within the scope of a current research project a hydrostatic transmission for wind turbines is being developed at IFAS. In this paper, two different strategies to control a hydrostatic transmission in wind turbines are presented and discussed. Main criteria are the optimal adaption of the system to the current wind situation and at the same time...

Wind tunnel experiments to prove a hydraulic passive rotor speed control concept for variable speed wind turbines (poster)

As alternative to geared and direct drive solutions, fluid power drive trains are being developed by several institutions around the world. The common configuration is where the wind turbine rotor is coupled to a hydraulic pump. The pump is connected through a high pressure line to a hydraulic motor and (synchronous) generator. However, in the...

Conceptual design of a DOT farm generator station

The Delft Offshore Turbine (DOT) is a DUWIND research project that focuses on reducing the cost of offshore wind energy by bringing a radical change in offshore wind turbine technology. The main concept is to centralize electricity generation by having individual wind turbines create a flow of pressurized seawater to a hydropower station. The...

MicroDOT: Design of a 10W prototype of the Delft offshore turbine

The Delft Offshore Turbine (DOT) project is a research project within DUWIND. The main objective of the project is to reduce the costs of offshore wind energy through technical solutions. A defining characteristic of the DOT concept is the fluid power transmission. The next step for the DOT concept is to make a full preliminary design. A helpful...

Dynamic modeling of fluid power transmissions for wind turbines

Fluid power transmission for wind turbines is quietly gaining more ground/interest. The principle of the various concepts presented so far is to convert aerodynamic torque of the rotor blades into a pressurized fluid flow by means of a positive displacement pump. At the other end of the fluid power circuit, the pressurized flow is converted back...