Development of a Hardware-in-the-loop Simulation Platform for Safety Critical Control System Evaluation

During the lifetime of a nuclear power plant (NPP) safety electronic control system components become obsolete [7]. It is difficult to find replacement components qualified for nuclear applications [50]. Due to strict regulations, replacement components undergo extensive verification and operational analysis [70]. Therefore, the need for a platform to evaluate replacement safety control systems in a non-intrusive manner is evident. Verifying the operation or functionality of potential replacement electronic control systems is often performed through simulation [71]. To enable simulation, a physical interface between potential control systems and computer based simulators is developed. System connectivity is establish using Ethernet and standard industrial electrical signals. The interface includes a National Instruments (NI) virtual instrument (VI) and data acquisition system (DAQ) hardware. The interface supports simulator controlled transmission and receipt of variables. The transmission of simulated process variables to and from an external control system is enabled. This is known as hardware-in-the-loop (HIL) simulation [49]. Next, HIL interface performance is verified and the following are identified; a measure of availability; the effect of varied configurations; and limitations. Further, an HIL simulation platform is created by connecting a NPP simulator and a programmable logic controller (PLC) to the interface, Canadian Deuterium Uranium (CANDU) reactor training simulator and Invensys Tricon version nine (v9) safety PLC respectively. The PLC is programmed to operate as shutdown system no. 1 (SDSl) of a CANDU reactor. Platform availability is verified and the response of the PLC as SDSl and is monitored during reactor shutdown. Proper execution of the steam generator level low (SGLL) logic on the PLC and variable transmission are observed. Thus, a platform and procedure for the evaluation of replacements for obsolete electronic control system components is demonstrated