Bridging Scales With the Shift Frequency: Frequency-adaptive simulation of multiscale transients in power systems

One of the most remarkable features of power and energy systems pertains to their extremely far-reaching scales, which are unique in the field of engineering. In continental Europe, for example, the synchronous ac power system integrates capitals from Lisbon to Warsaw and from Athens to Copenhagen. Reaching farther out to the north, high-voltage dc (HVdc) links connect to Sweden and the United Kingdom. And as in other regions of the world, those grids are being further developed to integrate more renewables. This only adds to the diversity of technologies in the power grids and contributes to the wide range of timescales involved. Those range from electrothermal interactions in the range of minutes over electromechanical transients within seconds, down to microseconds or even faster for the electromagnetic transients of traveling waves.