Three way catalysts (TWCs) are installed downstream of internal combustion engines to mitigate the engine out pollutants generated from combustion. Accurate engine control systems are needed to achieve high conversion efficiency during vehicle operation and optimize TWC inputs. Accounting for TWC internal dynamics within the exhaust emission control design is key to enable improved engine and catalyst performance.

However, since internal TWC dynamics cannot be directly measured, modeling and estimation of the converter’s dynamics are essential for the development of high performing exhaust emission control strategies. In this paper, a Dual Extended Kalman Filter (dEKF) is designed and experimentally validated for the estimation of both the TWC oxygen storage level, $\varphi$, and age-dependent oxygen storage capacity, $OSC$. The estimator design is based on an experimentally validated physics-based TWC model developed by the authors in a previous work. Observer validation and performance evaluation are conducted over transient drive cycles in a chassis dynamometer. Moreover, observability properties and related estimation performance are analyzed using different sensor technologies. It is found out that using switch-type oxygen sensors in place of wideband oxygen sensors leads to a loss of observability within the model, preventing real-time OSC determination and, therefore, aging estimation. A Fisher information quantity study is developed and presented that provides quantitative guidelines for the optimization of TWC sensor design. Finally, the observer is tested on real hardware via rapid control prototyping.

三效催化剂（TWC）安装在内燃机的下游，以减轻发动机燃烧产生的污染物。需要精确的发动机控制系统以在车辆运行期间实现高转换效率并优化TWC输入。在废气排放控制设计中考虑TWC内部动力是提高发动机和催化剂性能的关键。

但是，由于无法直接测量内部TWC动力学，因此转换器的动力学建模和估算对于开发高性能排气排放控制策略至关重要。在本文中，设计了双扩展卡尔曼滤波器（dEKF）并通过实验验证了TWC氧气存储量的估算，$\varphi$以及与年龄有关的氧气储存能力， $Ø\mathrm{小号}C$。估算器设计基于作者在先前的工作中开发的基于实验的基于物理的TWC模型。观察者验证和性能评估是在底盘测功机的瞬态驱动周期内进行的。此外，使用不同的传感器技术分析了可观察性属性和相关的估计性能。已经发现，使用开关型氧气传感器代替宽带氧气传感器会导致模型内的可观察性下降，从而无法实时确定OSC并因此而导致老化估算。开展并提出了Fisher信息量研究，该研究为TWC传感器设计的优化提供了定量指导。最后，通过快速控制原型在真实硬件上对观察者进行了测试。