Optimal Power Sharing Control with Stability Enhancement for Islanded Microgrids

This paper proposes a novel evolutionary algorithm-based approach to optimize power sharing control of distributed generators (DGs) in islanded microgrids. The proposed approach is inspired by PID control, where the P-frequency term ensures the proportional power sharing among DGs, the I-frequency term avoids the frequency excursion, and the D-frequency term promotes better dynamic performance. First, this paper defines the objective of PID control, which is contributed by minimizing the power control cost and frequency overshot during transients. The objective is achieved by employing a particle-swarm-optimization (PSO) technique to seek for optimal settings of PID control. The PSO-PID power sharing control enables to minimize the control cost with more stable power sharing performance and stronger adaptability under different operating conditions. Simulation tests are carried out which prove the validity of this approach and its outperforming in the enhancement on control stability margin, compared to the conventional PID control.