A Strategy for Real Power Control in a Direct-Drive PMSG-Based Wind Energy Conversion System

As the penetration of wind energy into the power system continues to grow, wind energy conversion systems (WECSs) are increasingly expected to be able to control their output real power, while retaining their maximum power-point tracking (MPPT) capability. This paper proposes a simple real power control strategy, which augments the MPPT feature of modern WECSs, and is based on rapid torque control as opposed to the traditional pitch-angle control. This paper presents the implementation of the proposed control strategy for a direct-drive WECS that employs the permanent-magnet synchronous generator, even though the proposed method can also be extended to other classes of electronically interfaced WECSs. The paper also presents a parameter-tuning procedure for the proposed control strategy. The effectiveness of the proposed control strategy is demonstrated through mathematical analysis and time-domain simulation studies.