A fuzzy based adaptive controller for grid connected DFIG based windfarm for damping SSR oscillations

Grid integrated wind energy conversion system is highly known among all renewable energy sources. Grid integrated wind farm undergoes many technical challenges. Wind farms need long transmission line for the grid integration. As long transmission line exhibits high inductive reactance, capacitive series compensation is required to improve the transmission capacity. Insertion of capacitive compensation in a line causes Sub Synchronous Resonance (SSR) Oscillations in the system. These oscillations may lead to a permanent damage in the turbine-shaft system. This paper proposes a novel fuzzy based adaptive controller for Rotor Side Converter (RSC) and Grid Side Converter (GSC) for damping SSR oscillations in a grid connected DFIG based wind farm. The paper describes the development of a mathematical model of the proposed system in detail and small signal stability for SSR oscillations is analyzed using Eigen value approach. Oscillation. Performance of the proposed controller is tested under varying operating conditions and it has been observed that the fuzzy based controller adopts the changes in the system operating conditions and gives satisfactory performance compared with conventional PI controller.