The accuracy with which power system transient stability limits can be calculated by computer simulation depends on the synchronous machine model. The saturation representation in the machine model can be improved now by non-linear magnetic finite element analyses of the machine. This paper describes steps taken to incorporate a saturation algorithm, based upon finite element analyses, into an 1100 bus power system stability program. Power transfer capability of a hypothetical system is compared using the finite element based algorithm versus the conventional algorithm based upon the manufacturer's open circuit saturation curve.