Sliding mode control of DFIG based variable speed WECS with flywheel energy storage

In this paper a so-called sliding mode control (SMC) technique is applied for variable speed wind energy conversion system (WECS) control with doubly-fed induction generator (DFIG). The paper also points out interesting performances of the double-fed induction machine (DFIM) used as flywheel energy storage system (FESS). In fact, adjusting the rotor speed can allow the induction machine to release the kinetic energy to the power system or to absorb this energy from the utility grid. The DFIM enables the decoupled control of system active and reactive powers in both steady and transient states. The effectiveness of the proposed DFIG based WECS control approach along with FESS is proved throughout computer simulations results.