Coordination of batches in flexible production
Knut Åkesson, Martin Fabian, Arash Vahidi · 2000
In chemical batch control applications the description of how to produce a batch can be expressed as a sequence of operations, some of which many be parallel or alternative. Such a description is called a recipe. Each operation can be carried out by a resource, e.g. vessel or reactor. When several recipes execute concurrently within a plant there is a possibility for deadlock between recipes that share resources. A deadlock might lead to the loss of an entire batch, something that is costly and must therefore be avoided. This paper focuses on the generation of a model that can be used for synthesizing a supervisor that prevents the batch control system from running into deadlock situations. The discussed recipes are highly flexible. In this paper recipes with alternative resources for operations, and with alternative operations, are discussed.