Equation-based Modeling and Control of Industrial Processes
Abstract:
Control systems are used in a vast number of different applications. However, despite the differences, the objective is similar. That is, to control the application in the most efficient manner possible. In order to find out what is most efficient, models are an important tool. The models can be derived using more or less physical relations, but there is a trend towards using more and more physical insights since it has the advantage that the model can be used in an extrapolating way. That is, it is possible to draw conclusions based on the model without having measurements from the considered operating region. This is a strength when optimizing the process and the best possible operating condition might very well be significantly different compared to usual operating conditions for which data is available.
The model building is a very large share of the work and it is therefore imperative to be able to reuse models developed for earlier applications. This makes equation-based modeling very interesting for companies such as ABB that develop control strategies for many different applications. ABB has therefore developed tools for equation-based modeling and control for a long time. These tools have also been successfully applied to many different processes, such as pulp and paper mills, power plants, cement industries, etc.
In this presentation, we focus on two different applications where equation-based modeling has been key in the process optimization. The first application is hot rolling mills, while the second application is harbor cranes.
Hot rolling mills are complicated industries where the overall model has to incorporate physical relations from many different domains, such as mechanics, thermodynamics and metallurgy. For hot rolling mills, ABB has developed a model that describes the material throughout the whole rolling including reheating, rolling and cooling. This model has been used to compute operating conditions that minimizes the energy consumption while maintaining the material properties.
For harbor cranes, ABB has developed a tool to improve the process of picking up coal from a ship and put it in a hopper at shore. In this context, process improvement normally means minimization of the cycle time, but today it is also important to limit the energy consumption.
Slides from the presentation
Biography:
Johan Sjöberg received the M.Sc., Lic. Eng., and PhD degrees from Linköping University, Sweden, in 2003, 2006, and 2008, respectively. He has been with ABB Corporate Research, Sweden, since 2008 where he is involved in research related to control and optimization for a broad spectrum of applications. In addition, he also holds a position as Assistant Professor at Linköping University, where he is working with research related to marine automation.