The co-electrolysis of CO₂ and H₂O in high temperature solid oxide electrolysis cells (SOECs) is a promising energy storage method for intermittent renewable energy sources. In this paper, a three-dimensional (3D) continuum model of a 3-kW 40-cell planar SOEC stack is employed to study the dynamic behavior and control strategy under variable working conditions. The dynamic responses of stack power, current density, output H₂/CO ratio and stack temperature are evaluated for a scaled real-time wind power input over a whole day. The fluctuation of the wind power input leads to SOEC stack temperature fluctuation, which illustrates the need for temperature control. Two representative cases with voltage step changes in both endothermic and exothermic operation modes are studied to predict the temperature control by the variation of excess air ratio. The effects of excess air ratio on both the steady-state temperature gradient and the transient temperature variation rate are analyzed in both cases. The temperature fluctuation is successfully controlled by applying an excess air ratio profile that changes with the wind power input.

在间歇性可再生能源中，高温固态氧化物电解槽（SOEC）中CO ₂和H ₂ O的共电解是一种很有前途的储能方法。本文采用3kW 40单元平面SOEC堆栈的三维（3D）连续模型来研究可变工作条件下的动态行为和控制策略。堆功率，电流密度，输出H ₂的动态响应针对一整天的实时比例风能输入，评估/ CO比和烟囱温度。风能输入的波动会导致SOEC烟囱温度波动，这说明需要进行温度控制。研究了在吸热和放热两种运行模式下电压阶跃变化的两种典型情况，通过过量空气比的变化来预测温度控制。在这两种情况下，都分析了过量空气比率对稳态温度梯度和瞬态温度变化率的影响。通过应用随风能输入而变化的过量空气比率曲线，可以成功地控制温度波动。