Dynamic modeling of fluid power transmissions for wind turbines

Dynamic modeling of fluid power transmissions for wind turbines

Diepeveen, N.F.B.
Jarquin Laguna, A.

Civil Engineering and Geosciences

Hydraulic Engineering

2011-11-29

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 to torque and speed by a hydraulic motor. The main advantage of a hydrostatic transmission over geared and direct drive systems is the possibility to vary the transmission ratio. Thus it is possible to operate with variable rotor speed (required for maximum energy extraction), whilst using a synchronous generator directly coupled to a grid, thereby eliminating the need for an AC frequency converter and a voltage transformer. Furthermore, hydraulic drives not only have a higher power density than electrical drives, but their use also allows for alternative arrangements of components. This provides the opportunity to significantly reduce the nacelle mass. Previous publications on fluid power transmissions for wind turbines have mostly been focused on the energy efficiency of the system, based on steady state simulations and mea- surements. Little has been mentioned about the dynamic behavior, especially regarding the inherent damping characteristics of fluid power transmissions. This paper presents a theoretical model of the fluid power transmission and the analysis of the influence of the main design parameters on the dynamic behavior of the system.

http://resolver.tudelft.nl/uuid:27622bd6-bbcc-4f5f-91d9-0f755bd1cc8d

European Wind Energy Association

Proceedings of the EWEA Offshore 2011 Conference, Amsterdam, The Netherlands, 29 November-1 December 2011

Institutional Repository

conference paper

(c) 2011 The Author(s)