Stability and Accuracy Analysis of a Distributed Digital Real-Time Co-simulation Infrastructure

Co-simulation techniques are gaining popularity amongst the power system research community to analyse future scalable Smart Grid solutions. However, complications such as multiple communication protocols, uncertainty in latencies are holding up the widespread usage of these techniques for power system analysis. These issues are even further exacerbated when applied to Digital Real-Time Simulators (DRTS) with strict real-time constraints for Power Hardware-In-the-Loop (PHIL) tests.In this paper, we present an innovative Digital Real-Time Co-simulation Infrastructure that allows interconnecting differentDRTS through the Aurora 8B/10B protocol to reduce the effects of communication latency and respect real-time constraints. The proposed solution synchronizes the DRTS interconnection by means of the IEEE 1588 Precision Time Protocol (PTP) standard to align executions and results obtained by the co-simulated scenario. The Ideal Transformer Method (ITM) Interface Algorithm(IA), commonly used in PHIL applications, is used to interface theDRTS. Finally, we present time-domain and frequency-domain accuracy analyses on the obtained experimental results to demonstrate the potential of the proposed infrastructure. With the presented setup, a time step duration down to50μsis shown to be stable and accurate in running an Electro-Magnetic Transients(EMT) co-simulated power grid scenario by interconnecting two commercial DRTS (i.e. RTDS NovaCor), extending the scalability of future Smart Grid real-time simulations.