System Modeling and Optimal Dispatching of Multi-energy Microgrid with Energy Storage

The coordinated operation and comprehensive utilization of multi-energy sources require systematic research. A multi-energy microgrid (MEMG) is a coupling system with multiple inputs and outputs. In this paper, a system model based on unified energy flows is proposed to describe the static relationship, and an analogue energy storage model is proposed to represent the time-dependency characteristics of energy transfer processes. Then, the optimal dispatching model of an MEMG is established as a mixed-integer linear programming (MILP) problem using piecewise linear approximation and convex relaxation. Finally, the system model and optimal dispatching method are validated in an MEMG, including district electricity, natural gas and heat supply, and renewable generation. The proposed model and method provide an effective way for the energy flow analysis and optimization of MEMGs.