Control of wind turbines: Past, present, and future

Abstract

Abstract-We review the objectives and techniques used in the control of horizontal axis wind turbines at the individual turbine level, where controls are applied to the turbine blade pitch and generator. The turbine system is modeled as a flexible structure operating in the presence of turbulent wind disturbances. Some overview of the various stages of turbine operation and control strategies used to maximize energy capture in below rated wind speeds is given, but emphasis is on control to alleviate loads when the turbine is operating at maximum power. After reviewing basic turbine control objectives, we provide an overview of the common basic linear control approaches and then describe more advanced control architectures and why they may provide significant advantages.

Genetic algorithm optimization for pitch angle control of variable speed wind turbines

“…Consider the mathematical description of the wind turbine as a control object [4,5]. The kinetic energy E, which the air stream has, depends on its mass and velocity can be determined by the formula:…”

“…The dependence of the wind turbine power factor Cp on λ and β is expressed in the form [4,5]: Using (5), (6), (8) and (9), we can represent the dynamic model of the wind turbine in the form of the structure shown in Figure 2. Figure 3 shows the dependence of the power factor of the turbine on the speed and the angle of inclination of the blades, found by formula (10).…”

Robust model predictive control of a wind turbine

“…On the other hand, they can reduce structural fatigue and therefore increase the lifetime of the wind turbine. There are several methods for wind turbine control ranging from classical control methods [1] which are the most used methods in real applications, to advanced control methods which have been the focus of research in the past few years [2]; gain scheduling [3] [5], nonlinear control [6], robust control [7], model predictive control [8], µ-Synthesis design [9] are just a few. Advanced model based control methods are thought to be the future of wind turbine control as they can conveniently employ new generations of sensors on wind turbines (e.g.…”

MixedH2/H∞pitch control of wind turbine with a Markovian jump model

“…Moreover, the stochastic characteristic of wind speed causes the the frequent switchings of wind turbine operating points, which brings further difficulty for control design to satisfy the above mentioned control strategy. Many authors have widely applied the modern control theory in the design of wind turbine control, such as linear-parameter-varying (LPV) control, model predictive control (MPC) or nonlinear feedback control, see [7,8,9,10,11,12,13,18,19,33,21,22,23,28,29,30,33]. Especially, [7] and [8] have designed the control law for wind turbine based on the gain scheduling method, where the switching law is satisfying a specific condition.…”