Low voltage performance improvement of a doubly fed wind generator through SMES

Variable speed doubly fed induction generators (DFIG) are preferred in wind generation systems because they offer several advantages in terms of control and aerodynamic efficiency. While it is generally a stable machine, its converter systems may not work properly under severe grid fault conditions. This article presents a strategy of riding through the low voltage conditions through control of superconducting magnetic energy storage (SMES) system. The reactive power supplied by the SMES helps the voltage recovery, while the real power improves the damping properties of the post disturbance system. Simulation studies show that the proposed SMES control strategy restores normal operation of the wind system in reasonably short period of time.