Real time economic dispatch considering renewable energy resources

In practice, the real time economic dispatch is performed in every 5–15 min intervals with the static snapshot forecast data. During the period between two consecutive schedules, generators participate in managing power imbalance, based on participation factors from previous economic dispatch. In modern power system with considerable renewable energy resources that have high variability, this conventional approach may not adequately accommodate the economic implication of the said variability. This paper proposes the evaluation of ‘best-fit’ participation factors by considering the minute-to-minute variability of solar, wind and load demand, for a scheduling period. The voltage, reactive power limit and line flow constraints are included for all minute-to-minute sub-intervals. Since ‘best-fit’ participation factors are evaluated only once, i.e., at the start of scheduling interval, the dimensionality of optimization problem remains the same as that of conventional approach. The proposed approach is suggested for sequential as well as dynamic variants. The proposed real time economic dispatch approaches are tested on IEEE 30 bus and 118 bus test systems considering variability in renewable energy sources and load demand.

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