In order to estimate wind turbine residL2;characteristics
in the presence of atmospheric turbulence, the important atmospheric
sources for the force excitations felt by the wind turbine system
must be identified and characterized. The goal of this research
is to develop the wind turbulence input model for horizontal axis
wind turbines....
The effects of selected atmospheric variables on the power output
of a DOE Mod-2 horizontal-axis wind turbine are studied. Particular
attention is focused on unsteady, nonuniform flow conditions
within the rotor disc as represented by vertical profiles measured at
adjacent meteorological towers. Primary variables are wind speed,
wind direction and...
The analysis of rigid hub, three-bladed horizontal-axis,
axisymmetric wind turbines in yaw is made using a linearized,
four-degree-of-freedom model. The linearized equations of motion of
rotor and nacelle are developed using quasi-steady blade element
theory and Lagrange's equations.
The yaw behavior of the system is studied from coefficients of
the...
Countries have begun to adopt green energy initiatives requiring high percentages of power generation to come from clean energy sources. Both onshore and offshore wind energy generates reliable clean energy. Due to this, wind energy has had an exponential growth in global adoption. While wind energy is increasingly adopted by...
A time domain simulation model which approximates the
three-dimensional velocity fluctuations of wind turbulence
has been developed. This model is used in a discrete time
control algorithm to regulate the output torque of a wind
turbine by changing the pitch angle of the turbine blade.
The wind model provides a...
The objective of this work was to develop a method for determining stochastic loads on horizontal axis wind turbine blades. Stochastic loads caused by wind turbulence are a major consideration in designing for long life, cost effective wind turbines. The rotor blades are of particular concern because the blades are...
This thesis presents and examines the concept that the output of a wound-rotor induction generator (WRIG) can be limited by means of linking to external impedances for wind-turbine generating system application. An 80kW-WRIG is simulated as a model to examine the control of the output power vs. speed characteristic. Model...
Development of variable speed horizontal axis wind turbines has resulted in a need for an analysis code with a rotor speed degree-of-freedom. This study develops a five degree-of-freedom time domain computer code that evaluates blade and rotor, mean and cyclic loads with nonlinear aerodynamics together with atmospheric turbulence as a...
Most existing analyses of the blade loads on horizontal
axis wind turbines are conducted using linear steady-state
aerodynamics, but evaluation of loads resulting from wind
turbulence or gusts may not be adequate using these
techniques. This study develops single-parameter
approximations for both the shed wake and trailing wake
components of...
