Screen Shot 2014-11-19 at 1.16.14 PMPower electronics based schemes require small timesteps to properly represent high frequency switching and circuit dynamics. To efficiently include such schemes in larger scale simulations, RTDS Technologies has developed the small timestep VSC subnetwork technique.

The VSC subnetworks operate with timesteps in the range of 1-4 µs and can be interfaced to large scale simulations operating with timesteps in the order of 50 µs. A key feature of VSC subnetworks is that the circuit and valve topology is user configurable. Two- and three-level converters can be freely configured to provide crow-bar circuits, etc. for PWM switching at greater than 2 kHz. A low-loss, fixed topology two-level converter is also available for operation at PWM switching frequencies in the range of 10 kHz.

Multiple VSC subnetworks can be linked together by traveling wave transmission lines or cables to create entire sytems running with timesteps <4 µs.

There are a variety of components available in the small timestep component library of the RSCAD software, including transformers, induction and synchronous machines, transmission lines and cables, and HVDC valve groups.

You can learn more about HVDC and FACTS applications here.

Our extensive list of technical publications contains published papers related to this topic.