EFFECTS OF IN-THE-LOOP INTERFACE FIDELITY ON THE SIMULATION OF NPP PROCESSES

摘要

The use of software in-the-loop (SWIL) and hardware in-the-loop (HIL) simulation to establish confidence in digital control systems with application to nuclear power plants (NPPs) is becoming increasingly common. In-the-loop simulation solutions; however, are often re-invented despite proven commercial platforms from dSPACE, National Instruments (NI) Veristand and Opal-RT. The capability of these custom in-the-loop simulation interface devices to provide accurate simulation results for verification and validation (V&V) purposes varies. Recently, a measurement of fidelity, namely transparency, for in-the-loop interfaces has been defined, calculated, and optimized for a simple HIL simulation platform. This paper introduces the study of in-the-loop interface fidelity to the nuclear industry whereby the fidelities of both a SWIL and HIL technique are measured. Further, an analysis of the measured fidelity and the accuracy of the respective simulations is performed. The two custom in-the-loop simulation platforms utilize Ethernet connectivity as is common practice within industry. As a benchmark, an actual single input single output (SISO) level control plant is utilized. Whereas, for in-the-loop simulations, a first principle model of the plant is executed within the MATLAB/Simulink simulation environment. The interface devices are composed of: for SWIL, object linking and embedding (OLE) for process control (OPC) communication which resides on top of dynamic data exchange (DDE) communications technology, and; for HIL, a National Instruments Virtual Instrument and Data Acquisition (DAQ) workstation, the User Datagram Protocol (UDP) and industrial 4-20 mA signals. An Invensys Tricon v9 programmable logic controller (PLC) with proportional integral (PI) controller is installed as SUT.