Robust Modelling Using Bi-Lateral Delay Lines for Real Time and Faster Than Real Time System Simulation

A very suitable method for modelling and simulation of large complex dynamic systems is represented by distributed modelling using transmission line elements (or bi-lateral delay lines). This method evolves naturally for calculation of pressures when hydraulic pipelines are modelled with distributed parameters. It is also applicable to other physical systems, such as mechanical, electrical, gas etc. One interesting application for distributed solvers using bi-lateral delay lines is in real time simulation. Modelling for real-time applications puts special requirements on robustness in the numerical methods used. In real-time applications there is no room for decreasing time step in numerically critical stages. Furthermore, if a system is relaying on a real-time simulation for its functionality, failure in the numerical properties is unacceptable. It is also in many applications possible to simulate the system faster than real time, which means that high fidelity system simulation can be used to plan ahead in control applications, and for simulation based optimisation.