PEMFC的最大运行功率和广义预测控制

Maximum power efficiency operation and generalized predictive control of PEM fuel cell

目前正在研究的一个重要问题就是如何使质子交换膜燃料电池(PEMFC)系统输出功率最大。然而,功率密度和很多因素相关,如电池的输出电压、燃料电池温度、阳极和阴极的压力及进气的湿度等,而且有着复杂的非线性关系。如果假定了电池输出电压和工作温度的范围,在此范围内,用二次多项式来拟合功率密度曲线并估计了燃料电池的最大功率点,再在广义预测控制(GPC)中增加了问题遗忘因子递推最小二乘法(FFRLS),以此来解决PEMFC各方面特性会随时间实时变化这个问题。基于近似拟合和广义预测控制方法,可以找到质子交换膜燃料电池的最大功率点,并使燃料电池一直保持工作在最大功率点,且当前消耗的氢气量最少。

Operating a proton exchange membrane fuel cell （PEMFC） system to produce power at the maximum power effJcJency was one of the key issues in PEMFC＇s wide-spread applications. However, power density exhibited complex behavior and nonlinear dynamics with respect to the output cell voltage, fuel cell temperature, anode and cathode pressure, inlet gas humidity, and so on. The distribution of power density in the domain of the output cell voltage and fuel cell temperature was delineated, By this delineation, the quadratic polynomial fitting was used to approximate the power density curve in local interval and estimate the maximum power efficiency point. Generalized predictive control （GPC） was presented to overcome the problem of time-varying dynamics of PEMFC in real time via applying a forgetting factor recursJve least square （FFRLS） method. Based on the approximation and generalized predictive control strategy, maximum power efficiency operation of PEMFC was applied. The results can contribute to the operation of PEMFC at the maximum power point, which guarantees the plant generating maximum power at the lowest consumption of hydrogen.