Stability Analysis of Multi Machine System Using Facts and Renewable Energy Source

In this paper, to achieve damping improvement of an offshore wind farm (OWF) fed to a multi-machine system using a static synchronous compensator (STATCOM) is presented. The operating performance of the studied OWF is simulated by an equivalent aggregated doubly-fed induction generator (DFIG) driven by an equivalent aggregated wind turbine (WT) through an equivalent gearbox. A fuzzy logic controller (FLC) plus adaptive neuro-fuzzy inference system (ANFIS) are designed to achieve adequate damping characteristics to the dominant modes of the test system under various operating conditions. A frequency-domain approach based on a linearized system model using ischolar_main-loci technique and a time-domain scheme based on a nonlinear system model subject to a three-phase short-circuit fault at the connected bus are systematically performed to examine the effectiveness of the proposed control schemes. It can be concluded from the simulated results that the proposed STATCOM integrated with the FLC plus ANFIS is shown to be superior for improving the stability of the system considered.