燃料电池发动机控制问题研究

燃料电池发动机控制问题研究

中文摘要

质子交换膜燃料电池是具有革命意义的新一代能源，近年来兴起的燃料电池汽车以其节能、清洁的优点代表了新一代汽车的发展方向。因此大力开发各种功率级别的安全、可靠的燃料电池系统成为了关键问题。由同济大学等机构研制的“超越”系列燃料电池轿车已经获得了阶段性的成果，但由于其燃料电池系统的燃料和空气是在低压(常压)状态下进行反应的，这造成燃料电池电堆的功率密度不高、响应速度不快以及加湿困难等问题，从而影响了燃料电池发动机的最大输出功率以及响应速度等动力性能。而高压燃料电池系统在解决这些问题上有着明显优势，由此引发了本文对高压燃料电池系统的研究。由于高、低压系统在控制要求上的主要不同在于：低压系统对反应气体的压力控制要求很低，而高压系统则有较严格的要求，因此本文围绕高压系统的气体压力控制以及与之相关的问题做了重点研究。

本文首先介绍了燃料电池、质子交换膜燃料电池以及燃料电池发动机的基本工作原理，描述了高、低压燃料电池发动机辅助系统的组成，并简要说明了它们之间的不同。其次通过对燃料电池极化现象的研究和对MK902电堆的实验数据分析建立了燃料电池电堆的输出特性模型，并在此模型基础上分析了工作压力的选择对燃料电池发动机性能的影响。

本文接着根据流体力学和热力学等理论建立了高压燃料电池发动机中空气

供应系统的数学模型，其中包括压缩机、供气管道、阴极流场以及背压阀等，为研究高压燃料电池系统中空气压力的控制奠定了基础。然后进行了燃料电池发动机的控制策略分析。从燃料电池发动机的失效分析着手，提出了控制系统的功能和目标；并根据高压燃料电池系统的特点，在原有“超越三号”发动机控制流程的基础上，设计出新的控制流程。

最后对高压燃料电池系统中的压力跟随控制问题进行了深入的研究。根据系统的特点，提出氢气压力跟随空气压力。从气路与电路的相似性出发，．创造性的建立了氢气供应系统的“电路”模型，并根据此模型提出了适合的控制算法。

关键词：燃料电池发动机、数学模型、压力控制

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Abstract

Proton exchange membrane fuel cell is a revolutionary new generation of energy, in recent years the rise of fuel cell car with its advantages of energy-saving, clean represents a new generation of automobile development direction. Therefore, vigorously develop various power levels of security, reliable fuel cell system has become the key problem. By the Tongji University and other institutions to develop " beyond" series of fuel cell car has already obtained the positive result of level sex, but because of its fuel cell system of the fuel and air in low pressure ( atmospheric ) under the state response, resulting in the fuel cell stack power density is not high, the response speed and humidification problems, thus affecting the fuel cell engine output power and speed of response, dynamic performance. While the high pressure fuel cell system to solve these problems have a clear advantage, resulting in the high pressure fuel cell system research. Due to the high, low pressure systems in the control requirements are: low voltage system on the reaction gas pressure control requirements are very low, and the high pressure system is more stringent requirements, this paper focus on the high pressure system of gas pressure control and related problem research.

This paper first introduces the fuel cell, proton exchange membrane fuel cell and fuel cell engine fundamental

The working principle, describes the high, low pressure fuel cell engine auxiliary system component, and a brief description of it

Between the different. Secondly through the fuel cell polarization phenomenon research and to the MK902 stack experiment data analysis to establish a fuel cell stack output characteristic model, and based on this model the analysis of working pressure on the fuel cell engine performance.

In this paper, according to the fluid mechanics and thermodynamics theory to establish a high pressure fuel cell engine air

Supply system mathematical model, which includes a compressor, gas pipeline, cathode flow field and backpressure valve,