Short-term energy storage for wind energy applications

The need to limit power fluctuations resulting from wind turbine generators (WTG) is becoming more important as wind energy reaches higher levels of penetration. This paper considers the integration of a short-term energy storage device in a doubly-fed induction generator (DFIG) design in order to smooth the fast, wind induced power variations. This storage feature can also enhance the low voltage ride through (LVRT) capability. The topology is evaluated in terms of its ability to improve both the steady state and transient performance. The system is modeled in EMTP and a number of cases and configurations are illustrated. Results show that when storage is sized based upon the LVRT requirement, it can provide improved performance both under steady state and during transients when compared with conventional technologies.