Contents 1 INTRODUCTION
Conventional complex dynamic system simulation tools (ex:[5], [2]) use the trapezoidal discretization method. Common drawbacks of the trapezoidal method are well known: among others, undamped switching oscillations and bad discretization of discrete components near the Nyquist limit. ARTEMIS’ proprietary discretization methods [1] bypass these limitations. The result is oscillation-free simulation of switching energy systems, without needing snubbers or other stabilizing schemes [3], and greater accuracy in circuits containing slightly damped components, which the well-known trapezoidal method sometimes handles deficiently. However, as with other fixed-time-step-capable simulation software like EMTP and the PSB, the standard ARTEMIS software cannot precisely simulate circuits that contain switches that toggle in the middle of time-steps. This is due to the non-iterative integration algorithm of these software packages, in which topology changes can only be taken into account at the beginning of the time-step. Events that occur in the middle of the time-step can only take effect at the following time-step. In switching topology systems, like thyristors or GTO converters, this discrete switching latency distorts the output spectrum of the simulation by introducing low frequency jitter components. This jitter is introduced by the simulation method and is not a real phenomenon. In feedback systems, like HIL, this jitter component can even lead to instability.
