含电转气的区域综合能源系统热电优化调度

Optimal Thermoelectric Dispatching of Regional Integrated Energy System With Power-to-gas

为提高区域综合能源系统(regionalintegratedenergy system,RIES)多能耦合利用效率,提出含电转气的变效率热电联产调度模型。首先分析电转气(power-to-gas,P2G)两阶段运行机理,在电解水制氢环节引入储氢,通过氢燃料电池(hydrogen fuel cell,HFC)热电联产促进氢能高品位使用,降低直接甲烷化造成的能量梯级利用损耗。其次将氢燃料电池与燃气轮机优化为变效率运行,通过调节热电效率灵活追踪热电负荷态势,使热电出力更为经济合理。然后引入有机朗肯循环(organic Rankine cycle,ORC)余热发电将热电联产过剩热输出转化为电能,通过促进余热消纳的方式改善系统的热电耦合性能。最后以系统购能成本、运行维护成本以及能量损耗成本之和最小为目标,构建含电转气的热电耦合RIES优化调度模型。通过算例仿真表明:相比传统热电联产系统,所提调度模型可促进多级能源高效利用,有效提高综合能源利用率与系统运行经济性。

In an attempt to improve the utilization efficiency of multi-energy coupling in regional integrated energy system(RIES),a variable efficiency co-generation dispatching model with power-to-gas(P2G)is proposed.Firstly,the two-stage operation mechanism of P2G is analyzed and the stored hydrogen is added in hydrogen production during water electrolysis process,which promotes the effective use of hydrogen energy through the cogeneration of hydrogen fuel cell(HFC),thereby reducing energy cascade utilization loss caused by direct methanation.Then,a variable efficiency operation model of hydrogen fuel cell and gas turbine is constructed,which makes the thermoelectric output more economical and reasonable by adjusting thermoelectric efficiency to flexibly track the integrated load situation.In addition,by introducing the organic Rankine cycle(ORC)waste heat power generation,the excess heat output from the co-generation is converted into electric energy.The thermoelectric coupling performance of the system is improved by promoting the waste heat accommodation.Finally,an optimal dispatching model of thermoelectric coupling regional integrated energy system with P2G is established,targeting the minimal sum of energy purchase cost,operation and maintenance cost,and energy loss cost.The simulation result shows that compared with the traditional co-generation system,the proposed model can promote the effective use of multi-level energy,and effectively improve the integrated energy utilization efficiency and operational economy of system.