Distributed Consensus Control of DFIGs with Storage for Wind Farm Power Output Regulation

Abstract

Today the state-of-the-art (SoA) wind generators (WGs) are the double-fed induction (DFIGs) with integrated storage devices. In the future, these WGs are expected to be one of the largest producers of renewable energy worldwide. In this paper, we propose a distributed control methodology for solving the problem of coordinating and controlling a group of SoA WGs to attain fast wind farm (WF) power output regulation with each storage device providing the same amount of power, i.e with equal sharing among the storage devices. Our proposed methodology introduces a consensus protocol for coordinating the grid-side converters (GSCs), whose dynamical equations constitute their closed-loop dynamics, and a particular closed-loop form for the interfacing capacitor dynamics. We establish stability of these closed-loop dynamics by leveraging singular perturbation and Lyapunov theories, proving that with these closed-loop dynamics DFIGs accomplish their assigned control objectives. Finally, we analytically construct a distributed and a Control Lyapunov Function (CLF) -based control law for the GSC and the DCDC converter respectively, which jointly lead to the desired closed-loop dynamics. We demonstrate the effectiveness of our methodology through simulations on the IEEE 24-bus reliability test system (RTS).