The Variable Speed Control Of Wind Turbines Based On Nonlinear Feedback Control

In industry, quadratic control law is the most commonly used variable speed controlmethod, but there's still no systematic stability analysis of the quadratic control law dueto the complexity of the power coefficient curve. In this dissertation, the relation betweenthe turbine angular speed and the aerodynamic torque is derived, and then the stabilityproof of the quadratic control law is given.Turbulence and other disturbances will lead to the drive-train torque ?uctuation ofthe wind turbine, which will reduce the reliability and life span of the gearbox. Tra-ditional control law based on the rigid body assumption can't resolve such a problem,consequently, the fatigue of the drive-train become seriously with the rapid growth ofwind turbine scale. In this dissertation, we use the method combined with the slidingmode control and back-stepping control to solve the problem, and whose effectivenesswere shown through the system simulation.