Hierarchical Optimal Operation for Integrated Energy System Based on Energy Hub

The integrated energy system(IES) has the characteristic of energy integrated/multi-energy coupling which involves heat, electricity, natural gas, and other various energy forms, which can realize maximize the synergistic effects and complementary benefits among various energy and the comprehensive utilization. In this paper, the day-ahead hierarchical optimal operation for IES coupling natural gas system, electricity transmission system and district heating system based on energy hub(EH) is studied. Firstly, the model architecture of EH with diversified storage devices, renewable energy and different energy conversion equipment is proposed and the steady state mathematical model of different energy networks in IES is developed, respectively. Secondly, the day-ahead operating cost of EH is minimized by optimizing strategy to maximize the benefits of all kinds of energy demand users, where different types of energy power input into EH can be obtained. Then, the day-ahead optimal operation mode for IES considering minimization of operating fuel cost index is proposed via energy management system giving various energy power data which are uploaded from EH. The numerical case verifies the validity of the day-ahead hierarchical optimal operation and steady state calculation analysis for IES.