含电转气的多能源中心协调优化运行策略

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

电转气技术的应用使得电力网络与天然气网络实现双向闭环能量流动,可以促进间歇性清洁能源的消纳。可将电转气细分为电转氢气、氢气转天然气2个过程并加入储氢设备以更好地协调电能-氢能-天然气能三者之间的能量流动。以系统运行成本最低及最大程度接纳风电为目标,计及电转气、天然气管网、各能源设备等运行约束构建了含电转气的多能源中心协调优化运行模型。模型对天然气网络潮流的非线性约束进行了线性化处理,加入权重系数将双目标优化问题转化为单目标优化进行求解。最后为了验证所建立模型的有效性和可行性,选取了4节点的多能源网络系统进行实例仿真分析,通过调用YALMIP工具箱的分支界定法进行模型求解,并对不同权重系数下不同场景系统的运行成本及风电消纳率进行了分析,结果证明电转气在多能源中心运行中的可行性,且电转气的中间产物氢气利用需求越高,风电消纳的程度越大。

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.