The comparison of common control strategies in grid-connected double-fed wind generators

As the penetration of wind power is high, in power system planning, it is difficult to acquire the detailed model of wind generators to be installed because of the commercial secrets. This paper discussed the mathematical models and typical control strategies of grid-connected double-fed wind generator (DFIG), and established the electromechanical simulation model with the help of power system simulation software DIgSILENT. Furthermore, two typical vector control methods applied in DFIG-stator flux oriented control and stator voltage oriented control were compared from two aspects which were eigenvalue and dynamic response. It can be concluded that when suffered a large disturbance, the proposed two vector control methods are quite different, and it is necessary to consider more detailed model in system stability analysis. On the contrary, when small disturbance is supposed, the results of two control methods are almost identical, which illustrates strong robustness and small deviation by applying general model.