Transient Stability Enhancement of Doubly Fed Induction Machine-Based Wind Generator by Bridge-Type Fault Current Limiter

Transient stability is a major concern for doubly fed induction machine (DFIM). A DFIM-based wind generator is readily affected by faults at the grid side as its stator windings are interfaced to grid. However, the wind generators need to remain connected and continue operation during faults at the grid side according to the grid code requirements. Therefore, it is important to enhance the transient stability of the DFIM-based wind generators. To achieve enhanced transient stability of the DFIM, a bridge-type fault current limiter (BFCL) is proposed in this study. Symmetrical as well as unsymmetrical faults were applied to the test system to check the efficacy of the BFCL in transient stability enhancement. Simulations were carried out in Matlab/Simulink environment. To demonstrate the effectiveness of the proposed BFCL, its performance is compared with that of the series dynamic braking resistor (SDBR). Simulation results show that the BFCL is a very effective device to attain better stabilization of the DFIM and outperforms the SDBR in all aspects.