Coordinated Optimization Operation Strategy for Multi-Energy Center with Power-to-Gas Devices

Application of power-to-gas (P2G) technology enables the two-way closed-loop energy flow between the power network and the natural gas network, which can promote the accommodation of intermittent clean energy. The power-to-gas process is divided in this paper into two stages: power-to-hydrogen and hydrogen-to-natural gas, and added with hydrogen storage devices to better coordinate the energy flow between power energy, hydrogen energy and natural gas energy. Aiming at the lowest operating cost and maximum wind power accommodation, a coordinated optimization operation model is constructed for multi-energy center with power-to-gas devices considering the operational constraints of power-to-gas, natural gas pipe network and various energy equipment. The model linearizes the nonlinear constraints of the natural gas network power flow, and converts the bi-objective optimization problem into single-objective optimization by adding the weight coefficient. Finally, in order to verify the feasibility and effectiveness of the established model, a four-node multi-energy network system was selected for simulation analysis. The branch definition method of YALMIP toolbox was used to solve the model, and the operating cost and wind power accommodation rate of the system were analyzed under different scenarios with different weight coefficients. The results demonstrate that the power-to-gas is feasible in operation of the multi-energy center, and the higher the utilization demand of the intermediate hydrogen gas, the greater the wind power accommodation rate is.