Dominant root locus in state estimator design for material flow processes: A case study of hot strip rolling. (May 2017)

• Record Type: Journal Article
• Authors: Fišer, Jaromír; Zítek, Pavel; Skopec, Pavel; Knobloch, Jan; Vyhlídal, Tomáš
• Is Part Of: ISA transactions. Volume 68(2017:May)
• Page Start: 381
• Page End: 401
• Publication Date: 2017-05
• Subjects: Dominant root locus -- Material flow -- Constrained estimation -- Model-based observer -- Hot strip mill; Engineering instruments -- Periodicals; Engineering instruments; Periodicals; Electronic journals; 629.805
• DOI: 10.1016/j.isatra.2017.02.004
• Languages: English
• ISSNs: 0019-0578

Abstract

Abstract: The purpose of the paper is to achieve a constrained estimation of process state variables using the anisochronic state observer tuned by the dominant root locus technique. The anisochronic state observer is based on the state-space time delay model of the process. Moreover the process model is identified not only as delayed but also as non-linear. This model is developed to describe a material flow process. The root locus technique combined with the magnitude optimum method is utilized to investigate the estimation process. Resulting dominant roots location serves as a measure of estimation process performance. The higher the dominant (natural) frequency in the leftmost position of the complex plane the more enhanced performance with good robustness is achieved. Also the model based observer control methodology for material flow processes is provided by means of the separation principle. For demonstration purposes, the computer-based anisochronic state observer is applied to the strip temperatures estimation in the hot strip finishing mill composed of seven stands. This application was the original motivation to the presented research. Highlights: Analytic description of material flow processes. Introduction of anisochronic state observer. Dominant root locus technique applied to observer gain matrix tuning. Constrained state estimation guaranteeing dominant poles location. Observer design demonstrated on a case study of hot strip rolling.