A hierarchical system for economic dispatch with environmental constraints

This paper presents a new hierarchical power dispatch system which uses a combination of the offline and the online subsystems to both minimize the cost and reduce the SO₂ emission. A hierarchical structure is introduced in the offline subsystem which enables the subsystem to generate a coarse-to-fine guideline for balancing the cost and the emission. The online dispatch is computed according to the guideline provided by the offline system. The dispatch is fed back to update the offline computation layer by layer. In this way, the offline guideline can always be adapted to the current situation, and the overall dispatch tends to be optimal for a whole year period. The system is tested by using the data from the Cincinnati Gas and Electric Company