Rolling optimization of integrated electric and cooling systems considering heating inertia of pipelines

In integrated energy systems, large fluctuations of renewable energies can be lowered effectively through optimal scheduling for the district heating and electric power systems. In this paper, an optimal scheduling scheme is proposed with the following steps: 1) A pipeline decomposition-based method is developed for improving the accuracy of the heating system model; 2) Based on the improved heating system model, a rolling optimization model for the operation of district heating and power systems is established considering the dynamic virtual energy storage of heating inertia in heating pipelines and buildings; 3) The inequality equations of electric power flows obtained by the second-order cone optimization are taken as parts of the constraints; 4) A cost-function that can evaluate the minimization of the differences between exchange power and day-ahead scheduling power in the future time is set. In theory, the proposed method can accurately predict the powers of renewable energies and outdoor temperature several steps ahead. For verification, an integrated energy system composed of an IEEE-33 bus and a 13-pipeline heating system is applied to testing. The results show that the method has the capability of smoothing out the power fluctuations caused by renewable energies and load uncertainty.