GOALI: Hybrid Control of Continuous Casting for Whale and Crack Prevention

该奖项支持的研究工作旨在防止连续薄板坯铸钢中的两个主要问题：内部和表面裂纹和鲸鱼？凝固的钢壳的凸起。将创建基于模型的喷雾冷却控制系统，以在干扰和过程模型不确定性的情况下跟踪设计成满足质量约束的温度曲线。移动凝固前沿位置的控制将通过发展适用于许多过程的具有移动边界的系统的混合状态估计和控制理论来解决。研究方法的进展，从一个理想化的配置控制器/状态估计器系统的发展，真实的连铸机已约束喷嘴驱动，未建模的过程动态，和不可靠的高温计测量。成果包括基本控制理论成果、控制器和状态估计器综合与分析工具、纽柯钢铁公司工业连铸机上的软件/硬件演示与验证、离线教育过程控制与可视化工具、出版物中的研究成果文档以及工程专业学生教育。具有成本效益的控制系统，能够在连续薄板坯铸钢中完成复杂的喷雾冷却控制任务。这项研究将对整个行业产生广泛的影响，因为质量改进（通过减少缺陷），节能（通过提高产量和降低再加热成本），更好的安全性（通过提高钢材质量，减少漏钢和鲸鱼缺陷）和竞争力（通过铸造新的钢铁产品）。 改进喷雾冷却控制以实现产量损失即使减少1%也将每年节省约1亿美元（基于美国每年生产的约1亿吨钢和每吨100美元的净报废成本）。开发新的观测和控制工具--与不可靠传感器的传感器融合和对具有移动边界的系统的控制--将解决许多其他制造过程中遇到的问题。研究和教育基础设施将通过学生参与，行业和国际合作以及新知识的广泛传播得到显着增强。

The research effort supported by this award is aimed at preventing two major problems in continuous thin-slab steel casting: internal and surface cracks and whales ? bulges of the solidifying steel shell. A model-based spray cooling control system will be created to track, under disturbances and process model uncertainty, temperature profiles designed to satisfy quality constraints. Control of moving solidification front position will be addressed by developing theory of hybrid state estimation and control for systems with moving boundaries, applicable to a number of processes. The research approach progresses from the development of a controller/state estimator system for an idealized configuration to the real caster which has constrained spray-nozzle actuation, unmodelled process dynamics, and unreliable pyrometer measurements. Deliverables include fundamental control-theoretic results, controller and state estimator synthesis and analysis tools, software/hardware demonstration and validation on an industrial caster at Nucor Steel, an offline educational process control and visualization tool, documentation of research results in publications, and engineering student education.Once completed, the results of this research will offer widely applicable, cost-effective control systems capable of accomplishing sophisticated spray cooling control tasks in continuous thin slab steel casting. This research will have broad impact across the entire industry due to quality improvement, (through fewer defects), energy savings (through yield improvement and lower reheating costs), better safety (from improved steel quality, and fewer breakouts and whale-defects), and competitiveness (by enabling the casting of new steel products). Improving spray cooling control to achieve even a one percent reduction in yield loss would save about $100 million per year (based on the roughly 100 million tons of steel produced each year in the U.S. and $100 per ton net cost of scrapping). Development of novel observation and control tools - sensor fusion with unreliable sensors and control of systems with moving boundaries - will address problems encountered in many other manufacturing processes. The research and educational infrastructure will be significantly enhanced through student involvement, industry and international collaborations, and broad dissemination of new knowledge.