Unified modelling of gas and thermal inertia for integrated energy system and its application to multitype reserve procurement

Abstract

The multi-energy coupling characteristic of integrated energy system helps to promote energy efficiency improvement and facilitate renewable energy integration. However, the growing complexities from multi-energy coupling and the increasing uncertainties of renewable generations are both threatening the synergistic operation. It is imperative to fully exploit the flexibility of integrated energy system for operating reliability and economy. In view of the essential similarities from the slow dynamics of gas and thermal systems, a unified gas and thermal inertia model for integrated energy system is proposed in this paper for flexibility excavation and optimal allocation. First, gas and thermal inertia is uniformly defined considering inertial characteristics. Furthermore, a method for unified modelling of gas and thermal inertia is accurately illustrated based on the dynamic model of gas and thermal system. To prove the validity of the unified model, a multitype reserve procurement scheme considering gas and thermal inertia is proposed. A typical community-scale integrated energy system is employed as a test system. The simulation results demonstrate the potential ability of gas and thermal inertia to improve the operational flexibility, reliability and economy of integrated energy system.