Power system stability enhancement through optimal design of PSS employing PSO

Interconnected power systems are critically vulnerable to instability due to the disturbances in any one portion of the system. Even low-frequency oscillations and small disturbances may lead to an outage of the system. Properly tuned Power System Stabilizer (PSS) is an effective tool for the suppression of these oscillations. This paper proposes a novel approach to tune proportional-integral (PI), proportional-integral-derivative (PID) and lead-lag PSS for a single machine infinite bus (SMIB) network by using particle swarm optimization (PSO) to damp out low-frequency oscillations (LFOs). The effectiveness of PSO tuned PSS is investigated by comparing the simulation results with fixed gain conventional PSS. In addition, the eigenvalues and minimum damping ratios of the same network are compared with referenced work employing backtracking search algorithm (BSA) which provides confidence on the proposed approach.