Controlling Transient Behavior of Solid Oxide Fuel Cells Using an Invariant Property

该奖项的研究目标是解决重要但相互冲突的目标，即提高SOFC的负载跟踪能力，同时在剧烈的功率波动下保持安全的瞬态运行。不足的负载跟踪是由于运输延迟，使固体氧化物燃料电池容易在瞬态氢饥饿。氢饥饿将通过限制燃料利用率来解决，燃料利用率是SOFC中的关键性能变量，在最佳范围内。通过直接测量燃料利用率的瞬态控制是不切实际的，这是由于复杂和昂贵的传感要求。相比之下，所提出的方法将通过使用不变属性来实现这一目标。它的不变性相对于压力，温度和内部和外部的重整反应，承认简单的控制实施。这项研究将揭示这种属性存在的基本条件，并开发出一种正式的方法来推导它在一个模型独立的方式。通过将该特性与包含储能元件的混合SOFC系统的鲁棒控制策略相结合，将在实现上述瞬态控制的同时提高SOFC的负载跟踪能力，如果成功，本研究将使SOFC的可用性从均匀功率应用扩展到快速响应场景。它将提供可接受的瞬态响应，减少传感和有限的知识的系统动态，其中包括许多相互关联的物理现象。这项研究将打开一个通用的瞬态控制方法的可能性，适用于燃料类型，重整器类型，堆栈技术等的变化，它将降低模型识别和调整工作，在传统的方法是至关重要的需要。该研究将通过研究生研究、合作机会等方式，让来自多个工程学科的研究生和本科生参与，并将努力增加妇女和少数民族学生的参与。研究成果将通过大学和全系的外展活动以及出版物和参加会议来传播。

The research objective of this award is to address the important yet conflicting goals of improving load-following ability of SOFCs and simultaneously maintaining safe transient operation under aggressive power fluctuations. Deficient load-following is attributed to transport delays that render SOFCs susceptible to hydrogen starvation during transients. Hydrogen starvation will be addressed by limiting fuel utilization, a critical performance variable in SOFCs, within an optimal range. Transient control through direct measurement of fuel utilization is impractical due to elaborate and costly sensing requirement. In contrast, the proposed approach will achieve this objective by using an invariant property. Its invariance with respect to pressures, temperatures, and internal and external reforming reactions, admits simple control implementation. The research will reveal the underlying conditions for existence of this property and develop a formal approach for deriving it in a model independent manner. By integrating the property within robust control strategies for hybrid SOFC systems containing an energy storage element, it will improve the load-following ability of SOFCs while achieving the aforementioned transient control.If successful, this research will extend the usability of SOFCs from uniform power applications to rapid response scenarios. It will provide acceptable transient response with reduced sensing and limited knowledge of the system dynamics, which consists of numerous interconnected physical phenomena. The research will open the possibility of a generalized transient control approach for SOFCs that is applicable across variations in fuel types, reformer types, stack technologies, etc. It will lower the need for model identification and tuning efforts that are crucial in traditional approaches. The research will involve graduate and undergraduate students from multiple engineering disciplines through graduate research, co-op opportunities, etc. and will attempt to increase the involvement of women and minority students. Research results will be disseminated through university and department-wide outreach activities, and through publications and conference participation.