Response of a wind turbine blade to seismic and turbulent wind excitations

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5576048

Hong, R C.Y.

The dynamic behavior of a wind turbine blade under seismic and turbulent wind excitation is studied. Toward this goal a procedure is developed in which the Markov process theory and lto's stochastic differential equation are used to obtain equations for statistical moments of blade response variables. Such equations then can be used to determine certain moment stability conditions for any given set of parameters, and moment responses if the system is stable. This study is carried out through the following steps: 1) Derivation of equations governing the uncoupled flapping, coupled flap-lagging and flap-lag-torsional motions. Three components of turbulence and three components of earthquake are considered in the formulation. 2) Determination of the moment stability and responses of a blade for the flapping motion, the coupled flap-lagging motion, and the coupled flap-lag-torsional motion. The results show that for a constant rpm wind turbine generator the uncoupled flapping, coupled flap-lagging and coupled flap-lag-torsion of a wind turbine blade are very stable under normal operating conditions, and that torsion has little influence on the dynamic behavior of flapping and leadlagging motions. If the system is stable, the effect of turbulence on moment responses is greater than that of an earthquake; therefore, turbulence is likely the main cause for structural fatigue of wind turbine blades.

• OSTI ID: 5576048
• Country of Publication: United States
• Language: English

Related Subjects

17 WIND ENERGY
170602* -- Wind Energy Engineering-- Turbine Design & Operation
DYNAMICS
FLUID FLOW
MACHINERY
MECHANICS
MOMENT OF INERTIA
SEISMIC EFFECTS
STABILITY
TURBINE BLADES
TURBINES
TURBOMACHINERY
TURBULENT FLOW
WIND TURBINES