Stability of large horizontal-axis axisymmetric wind turbines

Conference · Mon Dec 01 00:00:00 EST 1980 · Alternative Energy Sources; (United States)

OSTI ID:7173667

Hirschbein, M S; Young, M I

This paper examines the stability of large horizontal axis, axi-symmetric, power producing wind turbines. The analytical model used includes the dynamic coupling of the rotor, tower and power generating system. The aerodynamic loading is derived from blade element theory. Each rotor blade is permitted two principal elastic bending degrees of freedom, one degree of freedom in torsion and controlled pitch as a rigid body. The rotor hub is mounted in a rigid nacelle which may yaw freely or in a controlled manner. The tower can bend in two principal directions and may twist. Also, the rotor speed can vary and may induce perturbation reactions within the power generating equipment. Stability is determined by the eigenvalues of a set of linearized constant coefficient differential equations. All results presented are based on a 3-bladed, 300 ft.-diameter, 2.0 megawatt wind turbine. Some of the parameters varied are; wind speed, rotor speed structural stiffness and damping, the effective stiffness and damping of the power generating system and the principal bending directions of the rotor blades. The results show that unstable or weakly stable behavior can be caused by aerodynamic forces due to motion of the rotor blades and tower in the plane of rotation or by mechanical coupling between the rotor system and the tower.

• Research Organization: NASA-Lewis Research Center Cleveland, Ohio
• OSTI ID: 7173667
• Report Number(s): CONF-801210-
• Journal Information: Alternative Energy Sources; (United States), Vol. 4; Conference: 3. Miami international conference on alternative energy sources, Miami Beach, FL, USA, 15 Dec 1980
• Country of Publication: United States
• Language: English

Related Subjects

17 WIND ENERGY
WIND TURBINES
AXIAL SYMMETRY
STABILITY
AERODYNAMICS
DESIGN
EIGENVALUES
LOAD MANAGEMENT
MATHEMATICAL MODELS
POWER SYSTEMS
ROTORS
ENERGY SYSTEMS
FLUID MECHANICS
MACHINERY
MANAGEMENT
MECHANICS
SYMMETRY
TURBINES
TURBOMACHINERY
170602* - Wind Energy Engineering- Turbine Design & Operation