Control of Bifurcation in a VSC Based STATCOM

In this paper, bifurcation analysis is performed on a two-level twelve-pulse voltage source converter (VSC) based STATCOM to study the impact of dc capacitor on stabilty of the system. STATCOM is modeled in D-Q frame with the reactive current controller. The non-linear feedback controller is designed to control the bifurcation of the STATCOM in the inductive region to eliminate the Hopf bifurcations and limiting point cycles. The results obtained using bifurcation analysis is validated by eigen value analysis and transient simulations.