International Journal of Engineering and Technology

This paper presents a design of a Single Input Fuzzy Logic Controller (SFLC) based Static VAR Compensator (SVC) for Dynamic performance enhancement of power systems. The SFLC uses only one input which is the signed distance and has the advantage of reduced number of rules. Improvement of dynamic response by the controller is illustrated in a bifurcation perspective. Bifurcation diagrams of steady state as well as periodic solutions are constructed using continuation method. From the bifurcation diagrams, the existence of various bifurcation points such as, unstable Hopf bifurcation (UHB), stable Hopf bifurcation (SHB), saddle node bifurcation (SNB) and period doubling bifurcation (PDB) are identified. With the use of tools of nonlinear dynamics, voltage collapse points, and chaotic solutions due to period doublings are unearthed. The effectiveness of the SFL controller over the conventional controller for SVC in delaying the incidence of Hopf bifurcation (HBF), SNB and hence increasing the loadability limit is illustrated for the test system.