Modelling of Processes in Solar-Grade Silicon Production

Abstract

As the solar cell market is continuing to grow, the opportunities for silicon producers specifically targeting a product quality adjusted to solar cell applications have increased. To improve the possibilities for automatic control and to add to the available data set, a certain effort must put into mathematical modelling of the processes involved in such a plant.In this study we will focus on developing a mathematical black-box model for one of the processes associated with Elkem Solar, which is a producer of silicon for solar cell applications. To be able to develop a model with a good fit to the system, the available data basis is closely investigated. Based on this investigation, input candidates are chosen, and the data sets used to adjust the model parameters and verify the model behaviour are selected. Several different model structures are tested for comparison, and the best models are determined based on the results when the models are applied to fresh data. Finally, we will evaluate whether or not the model is good enough for its intended use, as well as how it may be improved when the industrial plant becomes operational.