Grid synchronization of doubly fed induction generator in wind power systems

This paper presents a synchronization algorithm for grid connection of a doubly fed induction generator (DFIG) in wind generation system. The vector control scheme is used for the variable speed DFIG operation and to compensate phase difference between grid and DFIG stator voltages a PLL algorithm is used. After the synchronization, the generator is connected to the grid. A laboratory test bench has been set up in order to verify developed algorithm. The experimental set consists of a DFIG, variable speed induction machine and a back-to-back converter. The control algorithms run on eZdsp F2812 target equipped with a TI TMS320F2812 DSP. The experimental result shows that soft and fast synchronization is achieved at the minimum rotating speed.