ARTEMiS stands for Advanced Real-Time ElectroMechanical Simulator. It is a plug-in for the SimPowerSystems block set for Simulink that enables hard real-time simulation of SimPowerSystems models. The objective of hard real-time simulation is that all iterations of the model are completed in a prescribed amount of time at each time step.
Objectives
Hard real-time simulation's objective is different from that of the typical simulation objective. In a normal simulation, one wants the smallest total simulation time or put in another way, the smallest average simulation time step. The hard real-time simulation objective is to have the smallest maximum time step.
The second main objective of the real-time simulation is to maintain the simulation's accuracy. This is a potential problem in real-time simulation because it is made with fixed-step solvers. Compared with typical variable-step solvers, the usage of fixed-step solver can lead to inaccuracies because there is no built-in accuracy check within the solvers. A typical variable-step solver will compare its results with a higher-order algorithm to verify accuracy. With a fixed-step solver, there is no such verification and larger time steps always degrade simulation accuracy in some way.
ARTEMiS helps to reach real-time simulation objectives in several ways. ARTEMiS can extend the range of time step to achieve both speed and precision for real-time applications. In applications where network switching causes numerical oscillations that cannot be damped at time steps above minimum hardware limits, ARTEMiS solvers have good damping properties which can successfully damp spurious oscillations. Furthermore, in applications where some underdamped or high-frequency components, relative to the fastest possible sampling time must be taken into account, ARTEMiS improves the precision of these components compared to the trapezoidal or Tustin methods.
State Space Nodal Solving
Since version 6.0, ARTEMiS has offered a new solver called State-Space Nodal which combines the accuracy potential of state-space methods with the ability of the nodal approach to handle circuits with large numbers of switches. Consequently, ARTEMiS is no longer limited with regards to the number of coupled switches in a circuit which provides some edges in the modelization of microgrids or distribution networks in which artificial decoupling methods like stub lines cannot be used, but also in more standard systems like HVDC or SVC.
In switched power systems, ARTEMiS now comes with automatically Inlined Interpolation methods for thyristors and 2-level voltage inverters. These efficient solver methods detect and compensate for switching events occurring in the middle of time steps. The option works in conjunction with the RT-EVENTS block set and uses real-time optimized interpolation techniques to improve accuracy.
Special Model Options
ARTEMiS provides special model options. It comes with a saturable transformer model based which uses flux as state and causes algebraic loops. One can also use SimPowerSystems' continuous-time machine model in conjunction with Simulink higher-order fixed-step solvers. In some case, the use of higher-order solvers can increase notably the precision.
Finally, ARTEMiS comes with specialized models for real-time simulation such as ARTEMiS Distributed Parameters Line and ARTEMiS Stublines that enables distributed simulation of power systems on several CPUs or cores of standard PCs using RT-LAB. The ARTEMiS plug-in is specially designed to work in the RT-LAB real-time environment and proves very effective in helping the typical user reach their real-time simulation objectives.