Study on the digitalization of trip equations including dynamic compensators for the Reactor Protection System in NPPs by using the FPGA

다국어 초록 (Multilingual Abstract)

Advanced reactors, such as Small Modular Reactors or existing Nuclear Power Plants, often use Field Programmable Gate Array (FPGA) based controllers in new Instrumentation and Control (I&C) system architectures or as an alternative to existing analog-based I&C systems. Compared to CPU-based Programmable Logic Controllers (PLCs), FPGAs offer better overall performance. However, programming functions on FPGAs can be challenging due to the requirement for a hardware description language that does not explicitly support the operation of real numbers. This study aims to implement the Reactor Trip (RT) functions of the existing analog-based Reactor Protection System (RPS) using FPGAs. The RT equations for Overtemperature delta Temperature and Overpower delta Temperature involve dynamic compensators expressed with the Laplace transform variable, ‘s’, which is not directly supported by FPGAs. To address this issue, the trip equations with the Laplace variable in the continuous-time domain are transformed to the discrete-time domain using the Z-transform. Additionally, a new operation based on a relative value for the equation range is introduced for the handling of real numbers in the RT functions. The proposed approach can be utilized for upgrading the existing analog-based RPS as well as digitalizing control systems in advanced reactor systems.

참고문헌 (Reference)

1 "Westinghouse technology system manual"

2 Kwang-Seop Son, "System Requirements for DRPS"

3 Son Kwang-Seop, "Study on the Digitalization and Establishment Method of OTdT/OPdT Trip Setpoint of WEC-Typed RPS" KAERI 2020

4 "Standard 754-2019(Revision of IEEE 754-2008), IEEE Standard for Floating-Point Arithmetic"

5 Alan Oppenheim, "Signals and Systems" Prentice Hall 1996

6 M.L. Meads, "Signal and Systems" Kluwer Academic Publishers 1991

7 Shahabeddin Kamy, "Sensitivity analysis on the effect of software-induced common cause failure probability in the computer-based reactor trip system unavailability" 57 : 294-303, 2013

8 International Energy Agency, "Projected Costs of Generating Electricity" NEA 2020

9 D. K. Brid, "Nuclear Power in Australia, in: a comparative analysis of public opinion regarding climate change and the Fukushima disaster" 65 : 644-653, 2014

10 "IEC 62566, Nuclear Power Plants - Instrumentation and Control Important to Safety - Development of HDL-Programmed Integrated Circuits for Systems Performing Category A Functions"

11 KAERI, "Doosan heavy industry, Soosan ENS, T-bog, Development of safety system and controller against CCF in NPP (Final report)" MOTIE 2017

12 Nuscale Power, "Design of highly integrated protection system platform"

13 최종균 ; DONG YOUNG LEE, "DEVELOPMENT OF RPS TRIP LOGIC BASED ON PLD TECHNOLOGY" 한국원자력학회 44 (44): 697-708, 2012

14 Peter L. Hung, "Core Protection calculator system: past, present, and future" 2010

15 International Atomic Energy Agency, "Climate Change and Nuclear Power" IAEA 2020

16 IAEA, "Application of Field programmable gate arrays in instrumentation and control systems of nuclear power plants" 2016

17 KAERI, "Advanced Compact Nuclear Simulator Textbook" KAERI 1989

18 Tate Shorthill, "A novel approach for software reliability analysis of digital instrumentation and control systems in nuclear power plants" 158 : 108260-, 2021

19 Sejin Jung, "A PLC platform-independent structural analysis on FBD programs for digital reactor protection systems" 103 : 454-469, 2017