Fault Ride Through Capability Enhancement of DFIG Based Wind Farm Using Advanced Converter Topology

In last few years, the most accepted and prominent choice in wind farm technology is Doubly Fed Induction Generators (DFIGs). But it is vulnerable to faults, especially which relate to grid, as its stator winding is directly attached to the grid. For uninterrupted supply of power, the DFIG requires to be connected to the grid during the faults according to the grid code. Hence, improving the Fault Ride Through (FRT) capability is one of the major concerns to ensure the stable operation of DFIG based wind farms. This paper is focused on the performance of various converter-inverter topologies for transient stability analysis of DFIG. Thus far, two level and three level neutral point clamped converter-inverter topologies have been implemented in FRT analysis. However, the analysis has not yet been performed for the two newly introduced advanced topologies i.e. flying capacitor and Zsource model. Simulations had been executed using PSCAD/EMTDC simulation platform. The effect of different converter-inverter topologies on the terminal voltage and the DC-link voltage were demonstrated and compared. Simulation results show that flying capacitor model outperforms all the other converter-inverter topologies by all aspects.