Optimal Day-Ahead Load Scheduling for Voltage and Frequency Regulation in an Islanded Microgrid

Regulating bus voltage and system frequency within desired permissible limits in an islanded microgrid with Renewable Energy Sources (RESs) is a challenging task. Hence, an optimal day-ahead load scheduling for the islanded operation of a microgrid is proposed here, which caters to this issue. The loads in the microgrid are assumed to exhibit Demand Response (DR) characteristics. Load curtailment options are also used in the proposed approach to cater to generation deficit situations in the islanded microgrid. A novel multi-objective formulation is also proposed to ensure optimal day-ahead load scheduling and load curtailment by minimizing the cost of energy supplied and the voltage deviation at all buses throughout the day. The best-compromised solution obtained from the associated optimal Pareto front ensures optimal load schedule by keeping the bus voltages and system frequency within the desired limits. The test results obtained for the IEEE 33 bus distribution system prove the efficacy of the proposed formulation.