Reactive Power Compensation-based Low-High Voltage Fault Ride-Through Strategy for DFIG

Doubly-fed induction wind generators (DFIG) are particularly sensitive to changes in grid voltage due to the direct connection of the stator to the grid. The transient processes brought by low-high voltage chain faults are more severe than single faults, which makes it more difficult for DFIG to achieve fault ride-through. In order to improve the fault ride-through capability of DFIGs under low-high voltage chain faults, this paper analyses the transient process of low-high voltage chain faults of DFIGs and proposes a control strategy based on the cooperative control of reactive power compensation device and converter. A grid-connected DFIG wind farm model is established in MATLAB/Simulink to simulate the faults and verify the proposed ride-through strategy. Case studies shows that the SVC control introduced by the proposed method can reduce the amplitude of the DFIG terminal voltage during the fault and improve the fault ride-through capability of the DFIG.