Second-Order Cone Programming-Based Optimal Control Strategy for Wind Energy Conversion Systems Over Complete Operating Regions

Abstract

An efficient control strategy of a wind energy conversion system (WECS) plays a crucial role in wind power utilization. In this paper, a novel multivariable control strategy for a variable-speed variable-pitch WECS is proposed. It is designed for the complete operating regions of a wind turbine, including both of the partial load region and the full load region, with the objectives of maximizing energy capture, smoothing power output, alleviating drive train transient loads, and reducing pitch actuator activities. In particular, this paper considers the wind speed disturbance as norm-bounded, instead of deterministic or chance constraints in the widely used quadratic control methods such as linear quadratic Gaussian control and model predictive control. Moreover, the WECS control with the norm-bounded disturbance is formulated as a second-order cone programming (SOCP) problem that has not been previously employed for wind power control. Finally, simulation results are provided to demonstrate the validity of the proposed method.