水冷型PEMFC温湿度建模与智能控制

当负载电流一定时,质子交换膜燃料电池(PEMFC)的工作温度和质子膜的相对湿度是影响电池输出性能的主要因素。分析电池电流密度与最优工作温湿度的关系,建立基于温湿度耦合模型的最优温湿度操作条件的电压模型。通过对冷却水流量和阴阳极气体加湿度进行综合控制,保持电堆的工作温湿度在最佳状态,不仅保证了电池最优的输出性能,还可以延长其使用寿命。根据仿真试验结果比较可以看到,所建立的温湿度模型能够有效降低温湿度之间的耦合作用,设计的变论域模糊比例积分微分(PID)温度控制器和反向传播(BP)神经网络湿度控制器能够快速地响应负载电流的变化,明显减少进气气体湿度以及电堆出口冷却水温度的调节时间和超调量,具有更准确的控制精度。

Temperature and Humidity Modeling and Intelligent Control of Water-Cooled PEMFC

As the load current is constant,the working temperature and the relative humidity of the proton membrane of the proton exchange membrane fuel cell(PEMFC)are the main factors affecting the battery output performance.The relationship between battery current density and optimal operating temperature and humidity is analyzed,so that voltage model for optimal temperature and humidity operating conditions based on the temperature and humidity coupling model is established.Through the comprehensive control of the cooling water flow and the anode and cathode gas plus humidity,the working temperature and humidity of the stack are kept in the best state,which not only ensures the optimal output performance of the battery,but also prolongs its service life.According to the comparison of simulation experiment results,it can be seen that the established temperature and humidity model can efectively reduce the coupling between temperature and humidity.The designed variable universe fuzzy proportional integral differential(PID)temperature controller and back propagation(BP)neural network humidity controller can quickly respond to load current.The change of the air intake gas humidity and the adjustment time and overshoot of the cooling water temperature of the outlet of the stack are obv iously reduced,and the control accuracy is much more improved.