Simulation Scheduling of Variable-Structure Systems in OpenModelica

Abstract

We propose and implement a generic scheduling frame-work for OpenModelica to eliminate the simulation code corresponding to inactive components in a system-level model. This framework allows the model developer to auto-generate models corresponding to the discrete behavior of the underlying system, and then schedule their simulations. It also provides a Scheduler library in the Modelica language to help the model developer easily generate the schedule. The benefit of this approach is demonstrated with and without real-time simulations of a batch distillation system. The proposed approach also helps implement a sequential modular simulation to arrive at initial guesses for flowsheets, whose equations can then be solved simultaneously using the standard, equationoriented, approach of Modelica.