A two-stage robust operation approach for combined cooling, heat and power systems

Combined cooling, heat and power (CCHP) systems can supply electric and thermal energy to customers. With thermal storage units, energy usage efficiency of the CCHP systems with auxiliary boilers can be improved with low operational costs. However, uncertainty exists in renewable power generation as well as electric and thermal loads which significantly affects the CCHP system operation. Operational limit violation would occur due to errors in predictions of the uncertainty. In this paper, a two-stage robust operation approach is proposed to coordinate the operation of the thermal storage units and the CCHP units with the boilers while satisfying the operational limits. The thermal storage units are dispatched a day ahead in the first stage and the CCHP outputs are dispatched hourly in the second stage. The two-stage operation is coordinated through a robust optimization method with full consideration of the uncertainty. Thus, the second stage CCHP outputs can compensate the first stage thermal storage dispatch without any operational violation. Simulation results indicate high solution robustness against the uncertainty.