考虑电转气消纳风电的电–气综合能源系统双层优化调度

Bi-level Optimization Dispatch of Integrated Electricity-natural Gas Systems Considering P2G for Wind Power Accommodation

电转气（power-to-gas,P2G）技术使电力网络与天然气网络的单向耦合转变为双向耦合,其运行特性为风电消纳提供了有效途径。该文提出一种考虑电转气合理利用弃风并考虑天然气系统优化运行的电力–天然气综合能源系统双层优化调度模型。首先,介绍含电转气的天然气系统运行模型;其次,以基于价格的含电转气的天然气系统优化调度为上层模型,基于直流潮流的含风电和电转气的电力系统经济调度为下层模型,构建电–气综合能源系统双层调度模型;再次,根据下层模型的Karush-Kuhn-Tucher（KKT）条件将双层模型转化为单层模型,并对非线性方程进行线性化,从而将非线性模型转化为混合整数线性规划（mix-integerlinear programming,MILP）问题,并调用CPLEX求解器进行求解;最后,通过算例分析验证所提出模型的合理性与有效性,并证明电转气可以有效提高电网的风电消纳能力。

Power-to-gas （P2G） technique realizes the two-way coupling for the integrated electricity and natural gas systems, which provides an effective way for wind power accommodation based on its operating characteristic. This paper proposed a bi-level optimal dispatch model for integrated natural gas and electricity systems considering P2G process to reduce wind power curtailment and optimal operation of natural gas system. Firstly, operation model of natural gas system with P2G was presented. Secondly, the bi-level optimal dispatch model was developed. The upper level was formulated as a price-based optimal allocation problem for natural gas system with P2~ while the lower level is an economic dispatch model for electricity system with wind power and P2G based on DC power flow. Then, the lower model was converted and added into the upper model as constraints according to Karush-Kuhn-Tucher （KKT） optimality conditions, and the bi-level model was recast into a single level model. Nonlinear equations were linearized, and the model was transformed into a mix-integer linear programming （MILP） formulation, which is solvable by CPLEX. Finally, numerical case studies demonstrate the rationality and effectiveness of the proposed bi-level optimization model, and verify that P2G is effective on promoting wind power accommodation.