Enhancement of Power-Sharing and Stability Using PSO-Tuned PSS for Inverter-Based Islanded Microgrid

This paper outlines the development of a power system stabilizer (PSS) for enhancing the power-sharing and stability of a droop-controlled inverter-coupled microgrids. In conventional power systems, the power system stabilizer is employed to dampen low-frequency oscillations and ameliorate stability. In Inverter-coupled generating source-based microgrid the droop controller plays a vital role in maintaining systems stability. Increasing the droop coefficient will improve power-sharing, but the stability of the microgrid has an adverse effect with the introduction of oscillations in system frequency. To address this issue, a PSS is proposed. In this study, the PSS parameters are tuned utilizing the Particle Swarm Optimization (PSO) algorithm. The integral squared error of the frequency of generating sources is adopted as an objective function to fine-tune both the time constants of a lead compensator and the gain of the PSS. The efficacy of the proposed PSS is showcased through time-domain simulations and eigenvalue analysis. The outcomes are then juxtaposed with those obtained from a PSS based on a traditional approach, considering different droop gain values. The PSO-based PSS outperforms the conventional technique and needs fewer calculations by achieving faster power-sharing and enhancing the dampening of low-frequency modes.