Direct voltage control for grid synchronization of doubly-fed induction generators

This article delivers a novel direct voltage control scheme to synchronize doubly-fed induction generators (DFIGs) to the grids. The proposed scheme controls the stator terminal voltage of the DFIG, with the rotor converter operating at a constant frequency to track the grid voltage. The scheme requires less computational power and needs less tuning parameters, as compared with existing synchronization methods. The advantage of the proposed synchronization methodology is the minimization of possible transients that might arise when the DFIG is directly connected to the busbars without synchronization. Computer simulation and experimental results are presented to demonstrate the merits of the scheme.