  This paper presents a study of improvement in stability in a single machine
connected to infinite bus (SMIB) power system by using static compensator
(STATCOM). The gains of Proportional-Integral-Derivative (PID) controller in
STATCOM are being optimized by heuristic technique based on Particle swarm
optimization (PSO). Further, Bacterial Foraging Optimization (BFO) as an
alternative heuristic method is also applied to select optimal gains of PID
controller. The performance of STATCOM with the above soft-computing techniques
are studied and compared with the conventional PID controller under various
scenarios. The simulation results are accompanied with performance indices
based quantitative analysis. The analysis clearly signifies the robustness of
the new scheme in terms of stability and voltage regulation when compared with
conventional PID.
