Comparison of transient stability analysis and large-scale real time digital simulation

The KEPS Real Time Digital Simulator (RTDS^(R)) is the largest real time power system simulator ever built. A power system which includes 320 (3-phase) buses and 90 generators has been modeled and run in real time. Since such large-scale systems were involved, it was not practical to validate them using nonreal time electromagnetic transient programs such as EMTDC^TM or EMTP. Instead, the results of the real time electromagnetic transient simulation were validated by comparing transient stability simulations run using PTI´s PSS/E^TM program. The comparison of results from the two programs were in almost all cases very good. However, as expected, some differences did exist and were investigated. The differences in the results were primarily traced to the fact that the electromagnetic transient solution algorithm provides more detail and therefore greater accuracy than the transient stability algorithm. After finding very good comparison of results between the RTDS Simulator and PSS/E, and after investigating the discrepancies found, KEPCO gained the necessary confidence to use the large-scale real time simulator to analyze and develop their power system