Mitigating uncertain RESs in integrated energy system considering line pack of gas

With the integrated energy system becoming a focus of research and application, its flexibility and stability has become a major issue, facing the uncertainties due to the increasing penetration of RESs (renewable energy sources). In this paper, for the electrical-hydraulic-thermal-gas integrated energy system, considering the fact that the gas can be stored in large quantities in pipelines, a method to mitigate the RESs uncertainties by utilizing the line pack storage of gas pipeline is developed. The multi-energy flow model of the electrical-hydraulic-thermal-gas integrated energy system is established, in which line pack storage of natural gas is described. A decomposed sequential multi-energy flow calculation approach is employed to calculate the energy flows. A case study of the integrated energy system illustrates the effectiveness of the proposed method for dealing with the RESs uncertainties in short-term operation by adjusting the average pressure within natural gas pipeline.