Refactoring of Execution Control Charts in Basic Function Blocks of the IEC 61499 Standard

This paper deals with refactoring of execution control charts of IEC 61499 basic function blocks as a means to improve the engineering support potential of the standard in development of industrial control applications. The main purpose of the refactoring is removal of arcs without event inputs. Extended refactoring, proposed in this paper, also helps to get rid of potential deadlock states. The ECC refactoring is implemented as a set of graph transformation rules. A prototype has been implemented using the AGG software tool. The refactoring can help in implementing equivalent transformation of control programs without introducing errors.