Date of Award

Fall 2011

Project Type


Program or Major

Electrical Engineering

Degree Name

Master of Science

First Advisor

L Gordon Kraft


As wind turbines grow in size there are added strains within the mechanical structure that need to be mitigated to improve machine life. The current area of greatest concern is the premature failure of the gearbox box due to torque variations along the drive train. This thesis incorporates a fluid coupler into the turbine's drive train. Three different controllers are developed for this model with the goal of minimizing the torque variations seen by the gearbox and providing better generator speed regulation.

The result of this study shows that the addition of the fluid coupler is a major improvement to the system. The coupler removes a resonant peak from the transfer function and allows for better speed regulation. Because of this a standard PI-Controller provides good system level performance. The performance can be improved with state feedback controllers, but these are not a necessity when a fluid coupler is present.