Stability of hybrid simulation of dynamic systems

This note analyses the problem of stability of hybrid simulation of dynamic systems. Time delays and sample-and-hold operations do cause serious stability problems, and if frequently happens that considerable time and effort are wasted because instability is not known in advance of programming the simulation on the hybrid computer. However, if the system under investigation can be approximated in its response by an equivalent linear system, then it is possible to define a procedure which will predict in advance whether any proposed computing scheme is stable. The text describes one such procedure, together with its implementation as a software package which can be used to predict the stability of simulations of practical size. In addition, the text contains a number of examples which illustrate the application of the software package.