Synchronous plant at 400 kV is a different proposition to inverter based generation. The dynamic behaviour of the unit is dominated by the governor, AVR and limiter response, and the off-the-shelf models do not cover everything the Grid Code asks for. In particular the OEL, UEL and SCL behaviour needed to be represented at a level of detail that standard model libraries do not provide.

Aurora built a detailed PSCAD model of GT11 and GT12. The machine governor was implemented as a GGOV1 model partially developed within PSCAD, the AVR was an ST9C, and the OEL, UEL and SCL were all written as custom models tuned to the actual plant characteristics. The models were used to deliver Grid Code compliance evidence covering the GC0141 and PC.A.9 requirements for both RMS and EMT analysis.