Bioelectrochemical systems performing electromethanogenesis (EMG-BES) represent an emerging technology for Power-to-gas as well as wastewater treatment. Moreover, EMG-BES can be used as a high-capacity energy storage system to absorb surplus energy in the electrical grid. This paper presents a modelling approach, which is based on building an equivalent electric circuit of the EMG-BES, which can be used to emulate static and dynamic non-linear behaviour of EMG-BES for different input voltages, which is advantageous if compared to other existing models. This model is a suitable choice for future studies in the development of the electric converters for EMG-BES plants connected to the electrical grid. The proposed model consists of practical and commercial elements, including capacitors, resistors, voltage sources, and a diode. The modelling of non-linear behaviour is achieved by adding a diode to the model. Four simple tests were performed to determine the equivalent circuit parameters in a medium-scale EMG-BES prototype. This prototype was built by stacking 45 cells together and connecting them in parallel, and it was long-term operated and tested under different electric inputs to determine the model parameters. A comparative study was finally conducted as reported in this paper in order to validate the proposed model against experimental results and values collected with other models.

进行电甲烷生成（EMG-BES）的生物电化学系统代表着一种新兴的技术，可用于发电天然气以及废水处理。此外，EMG-BES可以用作高容量能量存储系统，以吸收电网中的多余能量。本文提出了一种建模方法，该方法基于构建EMG-BES的等效电路，可用于仿真不同输入电压下EMG-BES的静态和动态非线性行为，如果与其他现有模型。该模型是用于连接到电网的EMG-BES工厂的电转换器开发中未来研究的合适选择。提议的模型由实用和商用元素组成，包括电容器，电阻器，电压源和二极管。非线性行为的建模是通过在模型中添加一个二极管来实现的。在中等规模的EMG-BES原型中执行了四个简单的测试以确定等效电路参数。该原型是通过将45个单元堆叠在一起并并联连接而构建的，可以长期运行并在不同的电输入下进行测试以确定模型参数。最后，如本文所述进行了比较研究，以对照实验结果和其他模型收集的值验证所提出的模型。并经过长期操作并在不同的电输入下进行测试以确定模型参数。最后，如本文所述进行了比较研究，以对照实验结果和其他模型收集的值验证所提出的模型。并经过长期操作并在不同的电输入下进行测试以确定模型参数。最后，如本文所述进行了比较研究，以对照实验结果和其他模型收集的值验证所提出的模型。