Power Quality Constrained Optimal Management of Unbalanced Smart Microgrids During Scheduled Multiple Transitions Between Grid-Connected and Islanded Modes

In this paper, a novel power quality (PQ) constrained optimization framework for smart microgrids with nonlinear loads is proposed for scheduled multiple transitions between grid-connected and islanded modes. Loads, generation, and energy storage are optimally scheduled to maximize the overall microgrid profit, from selling energy to grid, while satisfying network and PQ constraints. Cost of power interruption to loads, steady-state frequency deviation during islanding, and power sharing among generators are considered. PQ and network constraints of three-phase unbalanced distribution microgrid are given in convex forms. Comprehensive simulation results are given for validating the proposed algorithm and effect of limiting total harmonic distortion on microgrid economics is investigated.