Time base synchronization for interconnecting Real-Time platforms in co-simulation

Co-simulation is a versatile technique for splitting a large system model into multiple components that can then be solved in parallel on interconnected simulation platforms. This is most useful for interconnecting diverse Real-Time platforms (possibly from different vendors). A challenge emerges from the discrepancy of the time base between the systems. Even a minute difference in the frequencies of the forcing functions (i.e. stiff voltage and current sources in simulations of electrical systems) will cause spurious drifting and low frequency oscillations in the simulation results. A resolution is proposed in this paper based on a synchronization signal originating from one platform called the master and sent to the others. The effectiveness of this approach is demonstrated through implementation on actual hardware, namely an interconnection between RTDS™ and Typhoon HIL platforms.