Architecture Design for NPP Co-Simulation Platform

The initial survey of simulation tools in the COSI project shows that most of the nuclear power plants in Finland use Apros as the main simulation tool for thermomechanical and automation processes. However, since Apros cannot simulate the detailed electrical system events, e.g. unsymmetrical faults like one phase fault of the electric system, the detailed electrical power system models are simulated in different simulation tools. In this regard, the aim of this deliverable was to design the architecture of the co-simulation platform for nuclear power plants. The co-simulation platform provides the opportunity to simulate the interaction between detailed models implemented in different simulation tools. The architecture design of the COSI platform bases on using the Matlab (or Python) as the Master program. APROS will be used in Open Platform Communications (OPC) server and Matlab will be the OPC client for connecting APROS, and connecting to other Power system simulators using the appropriate protocol, which depends on the simulator's features. In this architecture, the master program, e.g. MATLAB, delivers the mechanical model of APROS to the power system simulators, and in the same way, the master program will deliver the electrical model of power system simulators to APROS. The power system simulators can consist of different tools used for simulations like PowerFactory, Simulink etc.
This deliverable also reports on some of the main challenge of co-simulation in NPP using this kind of design of the architecture. In order to prove the appropriate working of the architecture, a simplified Apros and electrical models have been developed. The preliminary proof results show that the co-simulation, tested with simple control commands and different time scales, works as expected in the normal operation of APROS and Power system simulators. The real simulations using the exact NPP component models are planned to start in the later phase of the project.