This paper presents a new approach in Modelica that allows a modeler to separate a model into different partitions for which individual solvers can be assigned. In effect; this allows to use multi-rate and multi-method time integration schemes that can contribute to improve the efficiency of a (real-time) simulation.
The first part of the paper discusses basic consideration relating to modular (real-)time integration. Afterwards; the implementation of a convenient Modelica library for the partitioning of physical models is briefly described. Finally; the presented library is used to partition a detailed six degree of freedom robot model for modular simulation. The simulation performance of that partitioned model is compared to the simulation performance achieved by using “conventional” global solvers.
Keywords: Multi-rate / multi-method time integration; simulation; clocked discretized continuous-time partitions.
Proceedings of the 10th International Modelica Conference; March 10-12; 2014; Lund; Sweden
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