Planning Study of Electric-Thermal Integrated Energy System Based on System Coupling Degree

Heterogeneous energy coupling is a distinctive feature of integrated energy systems (IES) that distinguishes them from single energy systems, such as distribution systems. Aiming at the problem that the existing coupling degree fails to penetrate its impact on the overall performance of the system, this paper proposes a quantitative index for the coupling degree of the coupling unit and the coupling degree of the IES. On this basis, an IES planning model is constructed with the twin objectives of minimizing economic costs and maximizing system resilience, The model takes into full consideration the equipment operating constraints, the electricity/heat multi-energy flow balance equation, and the demand response characteristics. To solve this complex multi-objective optimization problem, an improved multi-objective particle swarm optimization algorithm (MOPSO) is used. Matrix laboratory (MATLAB) constructs a typical electricthermal IES example for simulation and analysis, which reveals the key law of the coupling degree and the performance of the system. The simulation results further demonstrate the tradeoff between economy and resilience through a two-dimensional Pareto frontier.