Multi-rate Nonlinear Observers for Process Monitoring, with Application to Polymerization Reactors

通常，与化学过程的安全性、产品质量和/或经济性能相关的关键量不能在线测量。然而，其他物理变量的在线测量总是可用的，这些必须用于估计和监测未测量的临界量。在这个项目中，一个动态模型，从所有的在线测量的额外的适当的反馈条款，将被用来建立一个状态观测器来估计系统的状态，从所有相关的临界量可以估计和监测。该项目旨在通过提供统一框架中的通用算法工具以及将其应用于化学过程的实用指南来改变当前工业过程监控实践，该研究旨在（a）推进非线性观测器理论和（B）使先进的非线性观测器能够并扩展其在基于模型的化学过程（包括聚合反应器）监控中的适用性。该项目的第一个目标是系统的一般方法的设计多速率多延迟非线性状态观测器的过程监测的发展。满足这一目标将涉及理论研究的努力，推进非线性系统理论的方法和结果。第二个目标是测试和评估理论算法框架对化学过程监控应用的实际适用性。特别是聚合反应的监测将是主要的应用领域。满足这一目标将涉及建模，仿真和观测器设计，通过应用所提出的项目的理论部分的一般算法，以及实验实施和测试。本文的研究希望能对非线性观测器的理论和算法有所改进，包括（a）多速率观测的正确处理和（B）非线性观测器设计中多延迟观测的正确处理。它还旨在推进非线性观测器的实际应用，以监测产品质量的化学过程的操作，包括聚合反应器的监测，通过启用和提高利用所有可用的在线测量。工作结果将通过在科学会议上的介绍、学术期刊出版物和项目专用网站向学术界和工业界的研究人员广泛传播。除了研究生，PI计划招募代表性不足的本科生在他们的实验室从事研究。

Very often, critical quantities related to safety, product quality and/or economic performance of a chemical process cannot be measured on line. However, on-line measurements of other physical variables are always available, and these must be used to estimate and monitor unmeasured critical quantities. In this project, a dynamic model, with additional appropriate feedback terms from all the on-line measurements, will be used to build a state observer to estimate the state of the system, from which all pertinent critical quantities can be estimated and monitored. The project aims at transforming current industrial practice on process monitoring, by providing general algorithmic tools in a unified framework, as well as practical guidelines for their application to chemical processes.The research aims at (a) advancing the theory of nonlinear observers and (b) enabling and expanding the applicability of advanced nonlinear observers for model based monitoring of chemical processes, including polymerization reactors. The first objective of the project is the development of as systematic general methodology for the design of multi-rate multi-delay nonlinear state observers for process monitoring. Meeting this objective will involve theoretical research efforts, to advance methods and results of nonlinear systems theory. The second objective involves testing and evaluation of the practical applicability of the theoretical algorithmic framework to chemical process monitoring applications. In particular, monitoring of polymerization reactions will be the principal application area. Meeting this objective will involve modeling, simulation and observer design by applying the general algorithms of the theory part of the proposed project, as well as experimental implementation and testing. The research hopes to advance the theory and algorithms of nonlinear observers, including (a) the proper handling of multi-rate measurements and (b) the proper handling of multi-delay measurements in nonlinear observer design. It also aims at advancing the practical application of nonlinear observers for monitoring product quality in the operation of chemical processes, including polymerization reactor monitoring, by enabling and improving the utilization of all available on-line measurements. The results of the work will be broadly disseminated to researchers in academia and industry through presentations at scientific conferences, scholarly refereed journal publications and through a dedicated web site for the project. In addition to graduate students, the PIs plan to recruit underrepresented undergraduate students to pursue research in their laboratories.