Project: RTDS Model Development for Italy-Montenegro HVDC
Monita is an HVDC link between Italy and Montenegro under construction by Toshiba. As part of this project, the HVDC control and protection need to be tested using a Real Time Digital Simulator (RTDS). TGS was hired by Toshiba to develop the RTDS AC network models required for testing.
TGS RTDS services:
- Investigation of Network Model for RTDS (both Italy and Montenegro sides)
- Power Factory models were converted to PSS/E files using a TGS in-house conversion program
- PSS/E cases were converted to RSCAD files using PSS/E to RSCAD conversion program
- New custom models were developed in RSCAD in order to represent non-standard exciters and power system stabilizers
- Node Count Reduction
- The size of the AC electrical network was reduced in order to minimize the number of RTDS racks required to model the AC networks
- Transmission lines with a small reactance were removed and the number of nodes were optimized to a minimum value
- Electrical machines were combined with their corresponding step-up transformers, again to minimize the number of nodes in RSCAD
- Model Verification — power flow, short circuit, dynamic response
- Determination of the Number of RTDS Racks — minimum number to minimize cost
Many modifications for PSS/E to RSCAD conversion program were needed to be done in order to properly perform the conversion. This was done through a lot of cooperation and discussion with RTDS engineers.
Verification of RTDS results against Power Factory was a challenging task due to different modeling of external grids, equivalent impedances, phase-shifting transformers, etc. in the two software packages.