Implementation of PLL algorithm in DFIG based wind turbine connected to utility grid

摘要

In this paper, the application of phase-locked loop (PLL) a control strategy implemented in a doubly fed induction generator (DFIG) to improve the control due to unbalance grid voltage in real-time grid synchronization. A traditional PLL based on dq conversion & also the impact of unbalanced voltage shown in this paper. All the simulations done in PSCAD software. The positive sequence component can be obtained correctly still the grid voltage is unbalanced therefore the PLL stability improved significantly. An improved PLL scheme proposes in this paper this proposed method is so fast and stable so that the wind generator system works constantly even if in main grid emergency conditions so this method employs in DFIG wind power system. Therefore, the system was modelled for both normal and abnormal conditions. Due to the application of PLL the system stability improved quickly.