Applications of Nonlinear State-Observers to Chemical Reactors

• Main Authors: Ching-Long Chen, 陳慶隆
• Other Authors: Jyh-Shyong Chang
• Format: Others
• Language: en_US
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/72557259164679082939

碩士 === 大同大學 === 化學工程研究所 === 89 === The chemical processes are often complex nonlinear system and limited instrumentation is available on the spot, it is always difficult to measure all the state variables on-line. When a chemical engineer needs the state variables to be monitored, controlled or optimized on-line, a state observer is required to estimate these state variables. A developed observer found in the literatures shall be designed to ensure a fast decay of the tracking error. In this article, some existing observers were surveyed and compared to choose an observer convenient to use in practice. In general, to design of a workable observer, one must assure that the state variables are observable and detectable based on the process dynamic equations. In this study, we developed an observer based on the design principle of Soroush (1997) with a variable observer gain calculated at each sampling time instant. Applications of the developed observer to a parallel reaction and an isothermal reversible reaction carried out in a continuous stirred tank reactor (CSTR), and a methyl methacrylate (MMA) solution polymerization reaction executed in a batch reactor, tracking of the states were achieved successfully under various situation.