Cooperative and Multirate Simulation: Analysis, Classification and New Hierarchical Approaches

Co-simulation – a properly defined and already thoroughly researched topic, some would think. One of the first things made clear in this book is that not even a universally gratifying definition for this term can be found. Although the vast areas of application and multitude of theoretical work in this field is not denied but even extensively described, the need for further investigations is explic-itly shown in the empirical survey conducted amongst more than fifty experts and the statistical analysis of selected literature in this area. In addition, the author presents a fairly untouched sub-ject within co-simulation of continuous systems: hierarchical approaches, where one co-simulation may coordinate further co-simulations beneath on several levels. These methods can assuage the trade-off between accuracy and speed, which in traditional co-simulation depends on the one, common macro step size, by allowing different synchronization step sizes on every co-simulation level. In addition, the author shows that while consistency is maintained, numerical stability can even be enhanced by the sensible introduction of further co-simulation levels, thus tackling one of the currently pressing challenges highlighted by the survey.