||This thesis is aimed to develop a mathematical model used as design tool in order
to increase the efficiency of Wind Turbines Drive Train (WTDT) using spatial multibody
formulation with Euler parameter coordinates. The multibody model correctly
describes the motion and inertial characteristics of simple/complex drive train. Using
lagrange multipliers associated with constraints of multibody systems can calculate the
reaction forces into drive train components, which enables stress analysis and design
process can be establish. In recent years, mathematical models for multibody dynamic
systems have become an important design and analysis tool. Multibody dynamic systems
are presented by series of rigid and/or flexible links containing a wide variety of
joint types. The mathematical models are defined by differential algebraic equations
DAE which can simulate large rotation systems. Several general-purpose computer
programs exist, which allow engineers to model complex mechanical systems and to
evaluate the dynamic characteristics of potential designs before building of prototypes.
This reduces cost and lead time in designs. These general-purpose simulation packages
have several drawbacks. They need to be operated by experienced engineers and
are numerically inefficient. As a result, extensive research efforts have been directed to
developing more efficient and user-friendly methods for modeling multibody dynamic
systems. In this work, Multibody computational code is developed using MATLAB.
Moreover, symbolic derivation has been carried out to derive explicit equation of motion
of wind turbines drive train. These equations are then available for numerical
integration, consequently calculate the dynamic forces to help in the design process of
such systems, The results contain angular velocities and reaction forces of drive train.
A rigid multibody dynamic model of a horizontal wind turbine drive train used in this
work is composed of rotor, gearbox, and generator. Gearbox is the most important
element in drive train which is composed of a planetary and a conventional parallel
axis gear. This subsystem is formulated to study the system dynamic behavior as an
integrated complete system. Multibody modeling of gear sets allowing the dynamic
analysis to establish design by computing the forces acting on gear body and gear
teeth. MATLAB model results were compared using MSC ADAMS software by using
actual WTDT case study parameter with grate similarity.