Pitch-controlled variable-speed wind turbine generation

TLDR

Variable‑speed wind turbines aim to maximize energy output while limiting drivetrain loads, but prior work only optimized energy statically and considered drivetrain loads alone. This paper investigates the operation of variable‑speed wind turbines equipped with pitch control. The authors control the turbine by adjusting generator and power‑converter settings at low to medium wind speeds to capture maximum energy, and by regulating aerodynamic power at high wind speeds using either pitch control or generator load control. Simulations show that the turbine can achieve optimal energy capture across a wide wind‑speed range while reducing main‑turbine loads.

Abstract

This paper covers the operation of variable-speed wind turbines with pitch control. The system the authors considered is controlled to generate maximum energy while minimizing loads. The maximization of energy was only carried out on a static basis and only drive train loads were considered as a constraint. In low to medium wind speeds, the generator and the power converter control the wind turbine to capture maximum energy from the wind. In the high-wind-speed regions, the wind turbine is controlled to maintain the aerodynamic power produced by the wind turbine. Two methods to adjust the aerodynamic power were investigated: pitch control and generator load control, both of which are employed to regulate the operation of the wind turbine. The authors' analysis and simulation show that the wind turbine can be operated at its optimum energy capture while minimizing the load on the mind turbine for a wide range of wind speeds.