Adaptive variable structure control law for a variable speed wind turbine

Abstract

The efficiency of the wind power conversions systems can be greatly improved using an appropriate control algorithm. In this work, an adaptive robust control for a doubly feed induction generator drive for variable speed wind power generation is described. In the presented design it is applied the so called vector control theory. The control scheme uses stator flux-oriented control for the rotor side converter bridge control and grid voltage vector control for the grid side converter bridge control. The proposed robust control law is based on a sliding mode control theory, that presents a good performance under system uncertainties. The stability analysis of the proposed controller under disturbances and parameter uncertainties is provided using the Lyapunov stability theory. Finally simulated results show, on the one hand that the proposed controller provides high-performance dynamic characteristics, and on the other hand that this scheme is robust with respect to plant parameter variations and external disturbances.