Benchmarking an AI-Guided Reasoning-Based Operator Support System on the Three Mile Island Accident Scenario

AI-Guided Reasoning-Based Operator Support System for the Nuclear Power Plant Management

Operator situational awareness in Nuclear Power Plant (NPP) control rooms is quintessential in ensuring plant safe operation. Towards improving situational awareness, a novel framework of the EYE - Expert Supervisory System capable of visually monitoring human machine interfaces (HMI) in cyber physical system (CPS) is proposed with target application in NPP control room environment. EYE applied on HMI (EYE-on-HMI), conceptually offers an unique opportunity to reduce human-in-the-loop errors inherent in feedback control systems and improve overall safety. While assessing the feasibility of the proposed framework, we reflect on implementation challenges and review key enabling state-of-the-art technologies for EYE-on-HMI framework. EYE-on-HMI as a framework is envisioned to be portable to various industrial applications with prospective safety improvement to next generation of commercial applications with “driverless” operations.

The author discusses human factors engineering as applied to main nuclear power plant (NPP) control room design, including the design principles, control room layout, control and information equipment, environment conditions, communications system, etc. The main control room for a new 300 MW NPP will be modified and improved on the basis of the Qinshan 300 MW NPP design. >

The design of computerized procedure presentation for nuclear power plants

New methods of information presentation and interface design are changing the working conditions in the modern Nuclear Power Plant (NPP) control room. Symptom-oriented EOPs (SOPs) with their structures and practical application are described. The Computerized Symptom-oriented Operating Procedures (CSOP) is researched, which can help the operator analyze all the symptom signals of steam generator tubes rupture (SGTR) and provide the computerized procedures corresponding to the symptom signals. This paper analyzes the accident of SGTR; the accident management of SGTR is important in reactor safety because SGTR is one of the relatively high-frequency events in pressurized water reactors PWRs. The symptom signals of SGTR and the possible accidents corresponding to the symptom signals are analyzed. The homologous measures of symptoms are summarized. The disposal of SGTR adopts the method of based on symptoms. The programs are developed by VxWorks that is a real-time operating system. The debugging of programs is processed on simulator. The test results indicated that the programs can provide operating procedures according to the symptoms of accidents. After adopting the Computerized Emergency Operating Procedures, the labor intensity and mental burden of operators are lightened. Computerized Emergency Operating Procedures can enhance the reliability, safety and efficiency of Nuclear Power Plant.

Stability and steady state analysis of control and safety systems of Nuclear Power Plants

Control room modernization is an important part of life extension for the existing light water reactor fleet. None of the 99 currently operating commercial nuclear power plants in the U.S. has completed a full-scale control room modernization to date. Nuclear power plant main control rooms for the existing commercial reactor fleet remain significantly analog, with only limited digital modernizations. Upgrades in the U.S. do not achieve the full potential of newer technologies that might otherwise enhance plant and operator performance. The goal of the control room upgrade benefits research is to identify previously overlooked benefits of modernization, identify candidate technologies that may facilitate such benefits, and demonstrate these technologies through human factors research. This report describes a pilot study to test upgrades to the Human Systems Simulation Laboratory at INL.

Ergonomic field studies in a nuclear power plant control room

The shift from analog to digital Instruments (related mainly to information visualization) and Controls in Nuclear Power Plant Main Control Rooms (NPP MCR) is a central current topic of investigation. In NPP MCR, digitalization was implemented gradually, analog and digital systems still coexisting for the two main systems related to safety--Safety Instruments and Control System (SICS) and Process Instruments and Controls System (PICS). My ongoing research focuses on the introduction of Advanced Interaction Media (AIM) such as stereoscopic 3D visualization and multi-touch surfaces in control rooms. This paper proposes a Safety-Centric approach for gathering the Design Rationale needed in the specification of such novel AIM concepts as well as their evaluation through user tests. Beyond methodological research, the final output of the current research is to build an experimental simulator aiming to enhance improvements in Human-Systems Integration (HSI). This paper provides an overview of the topics under consideration.

The improvement of Human-Machine Interface (HMI) design for control rooms on nuclear power plants (NPP) has been accomplished world wide, especially after the TMI-2 accident. The design process and guidelines are standardized in IEC60964 and supplemental standards as international standard. However, technological update is required due to the increased use of computerized control and monitoring equipment and systems in control rooms on NPP in recent years. Standards are becoming more important for computerized control rooms because there is more freedom to design than conventional hardware based system. For computerized control rooms, standards for hardware and software of HMI systems should be also considered. Standards and guidelines for computerized control rooms on NPP have been developed recently in each body such as IEC, ISO, and IEEE etc. Therefore, reviewing these standards and guidelines related to control rooms design of NPP can be useful not only for revision of the international standards such as IEC60964, but also for users of the standards and guidelines. In this paper, we reviewed the international standards related to the design for control rooms, in the two aspects of HMI design and hardware and software design, considering the undergoing revision work and their application.

With the development of the nuclear technology, the instrumentation and control (I&C) systems have evolved from the analog systems to the current state-of-the-art digital systems. It has been reported that China has recently developed the digital systems based on Field Programmable Gate Array (FPGA) in CAP1400 nuclear power plant. And the lack of methods in the verification and validation work of the FPGA systems has become an important issue. This thesis describes the basic principles of FPGA, and the development process of FPGA. And then, the thesis proposes an effective improved method—formal verification, describing three methods of formal verification in detail, namely theorem proof, model checking, and equivalence proof. Describing the FPGA verification methodology and pointing out the shortcomings of traditional simulation, comparing the formal verification and traditional simulation verification in terms of complexity, timing, and applications. We also discussed the importance of formal verification method in FPGA. We selected the temperature and power control chip based on FPGA as an example, using System Verilog Assertions (SVA) method of model checking, and verifying the SRAM controller module and the internal calculation module. Through the analysis of the results, this paper proved the feasibility of formal verification methods in the instrumentation and control system of nuclear power plants, and provided some references of verification work for other system chips in instrumentation and control of nuclear power plant in the future work. The thesis showed that verification engineers can use the formal verification method based on SVA to verify the robustness of the system quickly and accurately. This method improves the controllability and observability which are the main drawbacks of the traditional simulation verification. It also avoids several issues in the debug process of traditional simulation verification, improving the accuracy and completeness of the chip verification.

As the development of computer science technology and the requirement of thorough research, more researchers are setting their eyes on coupling method because of the tight coupling in NPP (nuclear power plant) system. However there were few researches studying the difference between decoupling and coupling methods and the importance of coupling method. This research respectively establishes the primary and secondary loop decoupling models and the two loops coupling model based on the small NPP by APROS. Then the differences between the decoupling and coupling models is studied under the steady state and dynamic state which contains the ramp load variation and load shedding. The results show that there are small differences between these models in the main parameter values under the steady state. But the differences between decoupling models and coupling model are large. Therefore the NPP system needs be modeled by coupling method as to study its dynamic characteristic.

Control room modernization will be an important part of life extension for the existing light water reactor fleet. As part of modernization efforts, personnel will need to gain a full understanding of how control room technologies affect performance of human operators. Recent advances in technology enables the use of eye tracking technology to continuously measure an operator’s eye movement, which correlates with a variety of human performance constructs such as situation awareness and workload. This report describes eye tracking metrics in the context of how they will be used in nuclear power plant control room simulator studies.

Computerized procedures (CPs) are recognized as an emerging alternative to paper-based procedures for supporting control room operators in nuclear power plants undergoing life extension and in the concept of operations for advanced reactor designs. CPs potentially reduce operator workload, yield increases in efficiency, and provide for greater resilience. Yet, CPs may also adversely impact human and plant performance if not designed and implemented properly. Therefore, it is important to ensure that existing guidance is sufficient to provide for proper implementation and monitoring of CPs. In this paper, human performance issues were identified based on a review of the behavioral science literature, research on computerized procedures in nuclear and other industries, and a review of industry experience with CPs. The review of human performance issues led to the identification of a number of technical gaps in available guidance sources. To address some of the gaps, we developed 13 supplemental guidelines to support design and safety. This paper presents these guidelines and the case for further research.

This article proposes a cyber-security improvement plan for the DCS control system of nuclear power plants. Firstly, a brief introduction was given to the traditional architecture of DCS control systems of nuclear power plants. Secondly, the current cyber-security risks faced by DCS control systems in nuclear power plants were summarized, including identity authentication issues, access control issues, communication protocol issues, and data storage issues. Based on the cyber-security risks faced by the DCS control system in nuclear power plants, an improvement plan has been proposed for the DCS platform without increasing external cyber-security equipment. Firstly, regarding identity authentication, it is proposed that nuclear power plants have a very good physical protection that can effectively protect the operator station. However, for the engineer station, a dual factor identity authentication method needs to be added. Secondly, regarding access control, the shortcomings of role-based access control models were pointed out, and a location-based and task-based access control model was proposed. Then, in terms of security communication networks, the sensitive data range of nuclear power plants was analyzed, and communication was divided into internal communication and external communication. For internal communication, pre-stored keys can be used for encrypted communication. For external communication, certificates should be used for identity authentication, and then encrypted communication should be carried out. Finally, for data integrity, control system configurations can be saved through encryption. For passwords, they can be transmitted and saved through hash values.