Evaluation of state-based controlled STATCOM for DFIG-based WECS during voltage sags

Renewable energy sources have long since been recognized as environmental-friendly, sustainable and climate-neutral solution for future power systems. With the increasing penetration of renewable energy sources, particularly wind energy, as well as the growing percentage of power electronics-based devices and plants in the electrical supply grid, power quality issues ranging from voltage sags/swells, harmonics and unbalances to short-duration interruptions do pose a great challenge to the supply reliability. This paper investigates a state-based controlled shunt-connected power conditioner, the static synchronous compensator, to support DFIG-based wind energy conversion systems during supply grid voltage sags.