Novel multilevel STATCOM for power system stability enhancement on DFIG-based wind farms

Abstract

This work proposes the evaluation of the multilevel topology based on three-phase cells with a Single DC-link Cascaded H Bridge converter (SDC-CHB) with Model Predictive Control (MPC) as Static Synchronous Compensator (STATCOM) used to support DFIG wind farm operation. The well-known Hydro-Quebec system containing a 9 MW DFIG-based wind farm was chosen as a test bench to evaluate the proposed SDC-CHB steady and transient dynamic response to contribute to the DFIG fault ride-through. Simulation results demonstrate that the proposed topology enhances the power system stability and power quality, improving the voltage profile, on average, by 10% during symmetrical and asymmetrical faults. Furthermore, the SDC-CHB and MMC-CHB parametric study is presented proving the proposed topology robustness. Both topologies present similar steady and transient dynamic responses, corroborating that the proposed multilevel converter contributes to the DFIG fault ride-through with an enhanced topology when compared with classical multilevel converters.