Stabilization of Grid Connected Wind Generator by STATCOM

Abstract

Recently voltage-source or current-source inverter based various FACTS devices have been used for flexible power flow control, secure loading and damping of power system oscillation. Some of those are used also to improve transient and dynamic stability of wind power generation system (WPGS). In this paper, we propose the static reactive compensator (STATCOM) based on voltage source converter (VSC) PWM technique to stabilize grid connected squirrel cage wind generator system. A simple control strategy of STATCOM is adopted where only measurement of rms voltage at the wind generator terminal is needed, i.e. there is no need of reactive power measurement. Fuzzy logic controller is used as the control methodology of STATCOM, rather than conventional PI controller. The voltage sag and swell improvement of WPGS is compared with both fuzzy and PI controller. Moreover, the steady state capacitor value used with induction generator is reduced by certain percentage when STATCOM is used with WPGS. Comprehensive results are presented to assess the performance of the STATCOM connected with WPGS, where the simulations have been done by PSCAD/EMTDC.