Particle Swarm Optimization Optimized Controller for Static Synchronous Series Compensator to Improve Torsional Damping

This article uses particle swarm optimization, one of the derivative-free optimization techniques, to optimize the proportional-integral controller parameters of the DC-link voltage controller of a 48-pulse static synchronous series compensator. This particle-swarm-optimization-based proportional-integral controller is used to keep the voltage across the DC-link capacitor of a 48-pulse voltage-source-inverter-based static synchronous series compensator constant. The particle swarm optimization approach avoids the repeated trials that are needed in a trial-and-error approach to obtain near-optimum proportional-integral controller parameters. An objective function is proposed, which helps to improve the damping of modes near to the imaginary axis. The study system considered is the IEEE first benchmark model for sub-synchronous resonance. The stability of the system is determined from eigenvalue analysis. The article also shows that an optimized proportional-integral controller can improve the performance of the system with lower value of DC-link capacitor. Non-linear simulations are performed to verify the results of eigenvalue analysis.