Application of controllable resistive-type fault current limiter to low-voltage ride-through of DFIG

The resistive-type fault current limiter (FCL) may be applied to assist the low-voltage ride-through (LVRT) of the doubly-fed induction generator (DFIG). Considering the various fault scenarios, FCL with the fixed resistance may not provide flexible response to the different depths of terminal voltage drop. The controllable resistive-type fault current limiter (CRTFCL) is capable to adjust its resistance value to guarantee the satisfactory LVRT effect under different voltage drop depths. In this paper, the CRTFCL is applied to the LVRT of the DFIG. The different control targets of the DFIG during the LVRT, i.e., stator voltage control and active power output control, are selected and realized through the control to the resistance of the CRTFCL. The impact of the parameter setting of the CRTFCL resistance control on the LVRT effect is investigated. The numerical analysis is carried out with the different levels of the voltage drop. The control scheme to the CRTFCL resistance is simulated to show its feasibility and effectiveness to improve the LVRT effect of the DFIG.