Enhanced fault ride-through capability of DFIG wind turbine systems considering grid-side converter as STATCOM

Abstract

This paper proposes a combined control strategy of energy storage system (ESS) and braking chopper (BC) for fault ride-through (FRT) capability and generated output power smoothening of the doubly-fed induction generator (DFIG) wind power system. At the grid voltage sag, the DC-link voltage is controlled by the energy storage systems (ESS) instead of the grid-side converter (GSC), whereas the GSC is emploited as STATCOM to feed the reactive current into the grid for purpose of the grid voltage recovery. The validity of the proposed system is verified by simulation results for a 2-MW DFIG wind turbine system.