  The applications for IEC 61499 that is standard architecture for developing
the applications of distributed control and measurement in factory automation,
have the connected structure of the graphical elements called BFB(basic
function block), SIFB(service interface function block) and CFB(composite
function block). The research on the composite function block has been regarded
as important issues in implementing hierarchy, multi-functionality and
simplicity of software. Nowadays many researchers have been investigated
IEC61499 in the fields of the software modeling composed of basic function
block and service interface function block, the transformation from IEC61131 to
IEC61499 and syntactic extension of ECC of basic function block. However, work
related to the mathematical modeling for IEC61499 composite function block
using in designing software with hierarchical structure is still lacking. This
paper presents the mathematical model for the structure and execution analysis
of IEC 61499 composite function blocks by using notation of the set theory.
Also a subaplication configuration algorithm is suggested for the
subapplication corresponding to the composite function block. Then its
effectiveness through the computation experiment of several distributed control
applications is shown. The proposed model can be used effectively as a basis
for analyzing a runtime environment of a software tool for designing and
developing the applications.
