Mode changing stability of wind turbine in an integrated wind turbine and rechargeable battery system

摘要

Power generated by wind turbines changes due to variation in wind speed that is independent of the load power. Rechargeable batteries could be used as a reserve power source to alleviate unbalance between the load power and power generated by wind turbines. A supervisory controller is proposed for an integrated wind turbine-battery system (wind turbine electrically connected to a rechargeable battery). The switching conditions for wind turbine controller operating in multi-input and single-input control modes are discussed. Stability of the wind turbine controller switching between the two modes is analyzed using linearized, open-loop approximation of wind turbine dynamics at the switching instants. A Common Quadratic Lyapunov Function (CQLF) is established for both control modes to prove the system stability. Simulation results demonstrating system stability are also discussed.