燃料电池和电解池是化学能和电能间转化的装置，在减少碳排放，能量储存转换等方面发挥重要作用，在太阳能、风能等间歇性能源利用方面有着广泛的应用前景。气体再循环系统是燃料电池系统和电解池系统中的重要子系统之一，具有提高燃料利用率、回收排气热量等优点。固体氧化物燃料电池(SOFC)和固体氧化物电解池(SOEC)具有效率高、排放少、运行噪音小和易模块化等特点，但目前对于系统配置优化、动态预测和控制策略等方面的研究还不够深入。本文以SOFC和SOEC循环系统的建模和优化为研究对象，主要成果和创新点如下：（1）针对SOFC/SOEC的引射器和风机串联循环系统，设计了两种串联配置方案，搭建了引射器和风机串联循环系统实验装置，实验测试了串联配置和入口参数对系统总体性能的影响，利用引射器准二维模型和风机零维集总参数模型建立了串联系统的仿真理论模型。在所设计的工况下，风机在后时的串联系统增压性能提升可达10.9%。（2）针对SOEC制氢循环系统运行状态的预测和调控问题，基于电化学原理和有限体积法建立了SOEC电堆的一维电热动态仿真模型，基于有限体积法建立了换热器和加热器的一维动态仿真模型，利用Matlab Simulink平台实现了SOEC制氢循环系统的动态仿真，利用PID算法实现了对SOEC制氢循环系统运行状态的控制。电堆温度越高，水电解反应所需的吉布斯自由能越小，温度升高100℃，电能消耗可降低11.2%。（3）针对SOEC制氢循环系统的稳态建模分析和设计优化问题，提出了基于引射器循环的SOEC制氢循环系统构型，利用热力学和经济学理论建立了SOEC制氢系统电解池电堆、换热器、加热器、引射器、风机等部件的热力学和经济性模型，研究了SOEC制氢系统运行参数对系统制氢效率和成本经济性的影响，利用遗传算法实现了对两种循环系统的制氢效率和经济性的多目标优化，利用TOPSIS决策算法实现了SOEC制氢系统的选型和结构配置。基于引射器循环的SOEC制氢系统具有更高的效率和更低的成本，相比基于风机的制氢系统，热效率平均提升14.4%，投资成本节约1.4%。
Fuel cell and electrolytic cell are the conversion devices between chemical energy and electric energy, which play an important role in reducing carbon emissions, energy storage and conversion, and have a wide range of application prospects in the utilization of intermittent energy such as solar energy and wind energy. Gas recirculation system is one of the important subsystems of fuel cell system and electrolytic cell system, which has the advantages of improving fuel utilization rate and recovering exhaust heat. Solid oxide fuel cell (SOFC) and solid oxide electrolytic cell (SOEC) have the characteristics of high efficiency, low emission, low operating noise and easy modularization, but the research on system configuration optimization, dynamic prediction and control strategy is not deep enough. This paper takes the modeling and optimization of SOFC and SOEC circulatory systems as the research object, and the main achievements and innovations are as follows:(1) For SOFC/SOEC series circulation system with ejector and blower, two series configuration schemes are designed, and an experimental device for series circulation system between ejector and blower is built. The effects of series configuration and inlet parameters on the overall performance of the system are tested experimentally. The simulation theoretical model of series system is established by using the quasi-two-dimensional model of ejector and zero-dimensional model of blower. Under the designed working conditions, the overall performance of the series system with blower behind ejector is better. Under the designed working conditions, the turbocharging performance of the series system with blower behind ejector can be improved by 10.9% compared to the system with blower before ejector.(2) Aiming at the prediction and regulation of the operating state of SOEC hydrogen production cycle system, a one-dimensional electrical and thermal dynamic simulation model of SOEC reactor was established based on electrochemical principle and finite volume method, and a one-dimensional dynamic simulation model of heat exchanger and heater was established based on finite volume method. The dynamic simulation of SOEC hydrogen production cycle system is realized by Matlab-Simulink platform, and the running state of SOEC hydrogen production cycle system is controlled by PID algorithm. The higher the stack temperature, the smaller the Gibbs free energy required for the hydro-electrolysis reaction, and the electrical energy consumption can be reduced by 11.2% when the temperature is increased by 100℃.(3) Aiming at the steady-state modeling analysis and design optimization of SOEC hydrogen production cycle system, a configuration of SOEC hydrogen production cycle system based on ejector cycle is proposed, and thermodynamic and economic models of the electrolytic cell reactor, heat exchanger, heater, ejector, blower and other components of SOEC hydrogen production system are established by using thermodynamic and economic theories. The effects of system operating temperature, pressure, current and other parameters on the efficiency of hydrogen production of SOEC system based on ejector cycle and blower cycle were studied. Genetic algorithm was used to achieve multi-objective optimization of hydrogen production efficiency and economy of this two kinds of circulation systems. TOPSIS decision algorithm was used to realize the selection and structural configuration of SOEC hydrogen production system. The ejector-based SOEC hydrogen production system has higher efficiency and lower cost, with an average increase in thermal efficiency of 14.4% and cost savings of 1.4% compared to the blower-based system.
